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Brügelmann M, Müller S, Bohlen AV, Hohenfellner K, Büscher A, Kemper MJ, Fröde K, Kanzelmeyer N, Oh J, Billing H, Gellermann J, Müller D, Weber LT, Acham-Roschitz B, Arbeiter K, Tönshoff B, Hagenberg M, Žebec MS, Haffner D, Zivicnjak M. Morphological changes and their associations with clinical parameters in children with nephropathic cystinosis and chronic kidney disease prior to kidney replacement therapy over 25 years. Pediatr Nephrol 2024:10.1007/s00467-024-06421-6. [PMID: 38850407 DOI: 10.1007/s00467-024-06421-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 05/07/2024] [Accepted: 05/21/2024] [Indexed: 06/10/2024]
Abstract
BACKGROUND Infantile nephropathic cystinosis (INC) is a rare lysosomal storage disorder, mostly and often firstly affecting the kidneys, together with impaired disharmonious growth and rickets, eventually resulting in progressive chronic kidney disease (CKD). With the introduction of cysteamine therapy, most pediatric patients reach adulthood with no need for kidney replacement therapy. Still, detailed changes in INC patients' clinical and morphological presentation over the past decades have not yet been thoroughly investigated. METHODS Two groups with a respective total of 64 children with INC and 302 children with CKD, both treated conservatively and aged 2 to 18 years, were prospectively observed in the time span from 1998 to 2022 with 1186 combined annual clinical and morphological examinations clustered into two measurement periods (1998 to 2015 and ≥ 2016). RESULTS In INC patients, thoracic proportion indices remained markedly increased, whereas body fat stores remained decreased over the past 25 years (+ 1 vs. below ± 0 z-score, respectively). Their CKD peers presented with overall improved growth, general harmonization of body proportions, and improved body fat stores, while INC patients only presented with an isolated significant increase in leg length over time (∆0.36 z-score). eGFR adjusted for age did not significantly change over the past 25 years in both groups. Alkaline phosphatase (ALP) showed a significant decrease in CKD patients over time, while remaining above normal levels in INC patients. CONCLUSIONS Disproportionate thoracic shape and impaired body fat stores remain the most characteristic morphological traits in INC patients over the past 25 years, while causal mechanisms remain unclear.
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Affiliation(s)
- Malina Brügelmann
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Sophia Müller
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Alina V Bohlen
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | | | - Anja Büscher
- Department of Pediatrics II, University Hospital Essen, Essen, Germany
| | | | - Kerstin Fröde
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Nele Kanzelmeyer
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Jun Oh
- Department of Pediatric Nephrology, University Children's Hospital Hamburg, Hamburg, Germany
| | - Heiko Billing
- Clinic for Pediatric and Adolescent Medicine, RHK Clinic Ludwigsburg, Ludwigsburg, Germany
| | - Jutta Gellermann
- Department of Pediatric Gastroenterology, Nephrology and Metabolic Diseases, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Dominik Müller
- Department of Pediatric Gastroenterology, Nephrology and Metabolic Diseases, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Lutz T Weber
- Pediatric Nephrology, Faculty of Medicine and University Hospital, Children's and Adolescents' Hospital, University of Cologne, Cologne, Germany
| | | | - Klaus Arbeiter
- Division of Pediatric Nephrology and Gastroenterology, Medical University Vienna, Vienna, Austria
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, Heidelberg, Germany
| | - Martina Hagenberg
- Children's Hospital St. Elisabeth and St. Barbara, Halle (Saale), Germany
| | | | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Miroslav Zivicnjak
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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Müller S, Kluck R, Jagodzinski C, Brügelmann M, Hohenfellner K, Büscher A, Kemper MJ, Fröde K, Oh J, Billing H, Thumfart J, Weber LT, Acham-Roschitz B, Arbeiter K, Tönshoff B, Hagenberg M, Pavičić L, Haffner D, Zivicnjak M. Chest configuration in children and adolescents with infantile nephropathic cystinosis compared with other chronic kidney disease entities and its clinical determinants. Pediatr Nephrol 2023; 38:3989-3999. [PMID: 37415042 PMCID: PMC10584709 DOI: 10.1007/s00467-023-06058-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 06/09/2023] [Accepted: 06/13/2023] [Indexed: 07/08/2023]
Abstract
BACKGROUND Infantile nephropathic cystinosis (INC) is a systemic lysosomal storage disease causing intracellular cystine accumulation, resulting in renal Fanconi syndrome, progressive kidney disease (CKD), rickets, malnutrition, and myopathy. An INC-specific disproportionately diminished trunk length compared to leg length poses questions regarding the functionality of the trunk. METHODS Thus, we prospectively investigated thoracic dimensions and proportions, as well as their clinical determinants in 44 pediatric patients with INC with CKD stages 1-5 and 97 age-matched patients with CKD of other etiology between the ages of 2-17 years. A total of 92 and 221 annual measurements of patients with INC and CKD, respectively, were performed, and associations between anthropometric and clinical parameters were assessed using linear mixed-effects models. RESULTS Patients with INC exhibited altered chest dimensions that were distinct from CKD controls, characterized by markedly increased chest depth to height and chest depth to chest width ratio z-scores (> 1.0), while those of patients with CKD were only mildly affected (z-score within ± 1.0). Ratio z-scores differed significantly between both patient groups from 2-6 years of age onward. The degree of chest disproportion in INC patients was significantly associated with both the degree of CKD and tubular dysfunction (e.g., low serum phosphate and bicarbonate) across three different age groups (2-6, 7-12, and 13-17 years). CONCLUSION Our data show an INC-specific alteration in thoracic shape from early childhood onward, which is distinct from CKD of other etiologies, suggesting early childhood subclinical changes of the musculoskeletal unit of the thoracic cage, which are associated with kidney function. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Affiliation(s)
- Sophia Müller
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Rika Kluck
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Celina Jagodzinski
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Malina Brügelmann
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | | | - Anja Büscher
- Department of Pediatrics II, University Hospital Essen, Essen, Germany
| | | | - Kerstin Fröde
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Jun Oh
- Division of Pediatric Nephrology, University Children's Hospital Hamburg, Hamburg, Germany
| | - Heiko Billing
- Clinic for Pediatric and Adolescent Medicine, RHK Clinic Ludwigsburg, Ludwigsburg, Germany
| | - Julia Thumfart
- Department of Pediatric Gastroenterology, Nephrology and Metabolic Diseases, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Lutz T Weber
- Pediatric Nephrology, Children's and Adolescents' Hospital, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | | | - Klaus Arbeiter
- Division of Pediatric Nephrology and Gastroenterology, Medical University Vienna, Vienna, Austria
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, Heidelberg, Germany
| | - Martina Hagenberg
- Children's Hospital St. Elisabeth and St. Barbara, Halle (Saale), Germany
| | | | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Miroslav Zivicnjak
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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3
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George RP, Winterberg PD, Garro R. Multidisciplinary and multidimensional approaches to transplantation in children with rare genetic kidney diseases. Pediatr Transplant 2023; 27:e14567. [PMID: 37522570 DOI: 10.1111/petr.14567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 10/31/2020] [Accepted: 11/16/2020] [Indexed: 08/01/2023]
Abstract
In this review, we describe the multidisciplinary, multidimensional care required to optimize outcomes for pediatric transplant recipients with rare genetic kidney diseases. Transplant success, recipient survival, and improvement in quality of life depend on collaboration between patients, families, and a team of specialists with medical, as well as nonmedical expertise. A multidisciplinary transplant team composed of experts from medicine, surgery, nursing, nutrition, social services, transplant coordination, psychology, and pharmacology, is now standard in most transplant centers and is critical to the success of a transplant. In addition to these professionals, other specialists, such as cardiologists, urologists, geneticists, metabolic disease specialists, occupational therapists, case management, child life, chaplain, and palliative care services, have a crucial role to play in the preparation, surgery, and follow-up care, especially when a pediatric patient has a rare genetic disorder leading to renal involvement, and the need for transplantation. In order to describe this multidisciplinary care, we divide the genetic renal diseases into five subgroups-metabolic and tubular disorders, glomerular diseases, congenital anomalies of the kidney and urinary tract, ciliopathies including cystic diseases, and miscellaneous renal conditions; and describe for each, the need for care beyond that provided by the standard transplant team members.
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Affiliation(s)
- Roshan P George
- Division of Pediatric Nephrology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Pamela D Winterberg
- Division of Pediatric Nephrology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Rouba Garro
- Division of Pediatric Nephrology, Department of Pediatrics, Emory University School of Medicine, and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
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Hohenfellner K, Zerell K, Haffner D. Cystinosis. Klin Monbl Augenheilkd 2023; 240:251-259. [PMID: 36977426 DOI: 10.1055/a-2022-8522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Cystinosis is a very rare autosomal recessive lysosomal storage disorder with an incidence of 1 : 150,000 - 1 : 200,000, and is caused by mutations in the CTNS gene encoding the lysosomal membrane protein cystinosin, which transports cystine out of the lysosome into the cytoplasm. As a result, accumulation of cystine occurs in almost all cells and tissues, especially in the kidneys, leading to multiple organ involvement. Introduction of drug therapy with cysteamine in the mid 1980s, along with the availability of renal replacement therapy in childhood, have dramatically improved patient outcome. Whereas patients used to die without therapy with end-stage renal failure during the first decade of life, nowadays most patients live well into adulthood without renal replacement therapy, and several reach 40 years. There is robust evidence that early initiation and sustained lifelong therapy with cysteamine are both essential for morbidity and mortality. The rarity of the disease and the multi-organ involvement present an enormous challenge for those affected and the providers of care for this patient group.
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Affiliation(s)
- Katharina Hohenfellner
- Klinik für Kinder- und Jugendmedizin/Kindernephrologie, RoMed Kliniken, Rosenheim, Deutschland
| | - Kirstin Zerell
- Rosenheim, kbo-Heckscher-Klinikum gGmbH, München, Deutschland
| | - Dieter Haffner
- Klinik für Pädiatrische Nieren-, Leber- & Stoffwechselerkrankungen, MHH, Hannover, Deutschland
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5
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Nießl C, Boulesteix AL, Oh J, Palm K, Schlingmann P, Wygoda S, Haffner D, Wühl E, Tönshoff B, Buescher A, Billing H, Hoppe B, Zirngibl M, Kettwig M, Moeller K, Acham-Roschitz B, Arbeiter K, Bald M, Benz M, Galiano M, John-Kroegel U, Klaus G, Marx-Berger D, Moser K, Mueller D, Patzer L, Pohl M, Seitz B, Treikauskas U, von Vigier RO, Gahl WA, Hohenfellner K. Relationship between age at initiation of cysteamine treatment, adherence with therapy, and glomerular kidney function in infantile nephropathic cystinosis. Mol Genet Metab 2022; 136:268-273. [PMID: 35835062 PMCID: PMC9395137 DOI: 10.1016/j.ymgme.2022.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 06/28/2022] [Indexed: 10/17/2022]
Abstract
Infantile nephropathic cystinosis, due to impaired transport of cystine out of lysosomes, occurs with an incidence of 1 in 100-200,000 live births. It is characterized by renal Fanconi syndrome in the first year of life and glomerular dysfunction progression to end-stage kidney disease by approximately 10 years of age. Treatment with oral cysteamine therapy helps preserve glomerular function, but affected individuals eventually require kidney replacement therapy. This is because glomerular damage had already occurred by the time a child is diagnosed with cystinosis, typically in the second year of life. We performed a retrospective multicenter study to investigate the impact of initiating cysteamine treatment within the first 2 months of life in some infants and comparing two different levels of adherence in patients diagnosed at the typical age. We collected 3983 data points from 55 patients born between 1997 and 2020; 52 patients with 1592 data points could be further evaluated. These data were first analyzed by dividing the patient cohort into three groups: (i) standard treatment start with good adherence, (ii) standard treatment start with less good adherence, and (iii) early treatment start. At every age, mean estimated glomerular filtration rate (eGFR) was higher in early-treated patients than in later-treated patients. Second, a generalized additive mixed model (GAMM) was applied showing that patients with initiation of treatment before 2 months of age are expected to have a 34 ml/min/1.73 m2 higher eGFR than patients with later treatment start while controlling for adherence and patients' age. These data strongly suggest that oral cysteamine treatment initiated within 2 months of birth preserves kidney function in infantile nephropathic cystinosis and provide evidence of the utility of newborn screening for this disease.
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Affiliation(s)
- Christina Nießl
- Institute for Medical Information Processing, Biometry and Epidemiology (IBE), Working group "Biometry in Molecular Medicine", Ludwig-Maximilians-University of Munich, Marchoninistr. 15, 81377 Munich, Germany.
| | - Anne-Laure Boulesteix
- Institute for Medical Information Processing, Biometry and Epidemiology (IBE), Working group "Biometry in Molecular Medicine", Ludwig-Maximilians-University of Munich, Marchoninistr. 15, 81377 Munich, Germany.
| | - Jun Oh
- Department of Pediatrics, Pediatric Nephrology, University Center Hamburg/Eppendorf, Martinistr. 52, 20251 Hamburg, Germany.
| | - Katja Palm
- Department of Pediatrics, University Hospital Magdeburg, Leipzigerstr. 44, 39120 Magdeburg, Germany.
| | - Peter Schlingmann
- Department of General Pediatrics, Pediatric Nephrology, University Children's Hospital Münster, Waldeyerstr. 22, 48149 Münster, Germany.
| | - Simone Wygoda
- KFH Pediatric Kidney Center Leipzig, Delitzscherstr. 14, 04129 Leipzig, Germany.
| | - Dieter Haffner
- Department of Pediatrics, Department of Pediatric Kidney, Liver and Metabolic Diseases, Medical School, Carl-Neuberg-str. 1, 30625 Hannover, Germany.
| | - Elke Wühl
- Department of Pediatrics I, Division of Pediatric Nephrology, University Children 's Hospital Heidelberg, Im Neuenheimer Feld 430, 69120 Heidelberg, Germany.
| | - Burkhard Tönshoff
- Department of Pediatrics I, Division of Pediatric Nephrology, University Children 's Hospital Heidelberg, Im Neuenheimer Feld 430, 69120 Heidelberg, Germany
| | - Anja Buescher
- Department of Pediatrics II, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147 Essen, Germany.
| | - Heiko Billing
- Department of Pediatrics, Riedstraße 12, 74321 Bietigheim-Bissingen, Germany.
| | - Bernd Hoppe
- KNZ - Kindernierenzentrum Bonn, Im Mühlenbach 2B, 53127 Bonn, Germany.
| | - Matthias Zirngibl
- Department of General Pediatrics/Hematology/Oncology, University Children's Hospital, Hoppe-Seyler-Str. 1, 72076 Tübingen, Germany.
| | - Matthias Kettwig
- Department of Pediatrics, University Hospital Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany.
| | - Kristina Moeller
- Department of Pediatrics, Gesundheit Nord, Klinikverbund Bremen, Kürfürstenallee 130, 28211 Bremen, Germany.
| | - Birgit Acham-Roschitz
- Department of Pediatrics, Medical University of Graz, Auenbruggerplatz 34, 8036 Graz, Austria.
| | - Klaus Arbeiter
- Pediatric Dialysis Unit, Clinic of Pediatric and Adolescent Medicine, Department of Pediatric Nephrology and Gastroenterology, Medical University Vienna, Währinger Gürtel 18-20, 1090 Vienna, Austria.
| | - Martin Bald
- Department of Pediatric Nephrology Olgahospital, Clinics of Stuttgart, Kriegsbergstr. 62, 70174 Stuttgart, Germany.
| | - Marcus Benz
- Pediatric Nephrology Dachau, Schleißheimerstr. 12, 85221 Dachau, Germany.
| | - Matthias Galiano
- Pediatric Nephrology, Department of Pediatrics and Adolescent Medicine, University Hospital of Erlangen, Loschgestr. 15, 91052 Erlangen, Germany.
| | - Ulrike John-Kroegel
- Department of Pediatric Nephrology, University Children's hospital Jena, Kastanienstr. 1, 07747 Jena, Germany.
| | - Guenter Klaus
- Pediatric Rheumatology, University Children's hospital, Philipps University of Marburg, Baldingerstr, 35043 Marburg, Germany.
| | - Daniela Marx-Berger
- Children's Hospital of Eastern Switzerland, Claudiusstr. 6, 9006 St. Gallen, Switzerland.
| | - Katja Moser
- Children's Hospital Aschaffenburg, Am Hasenkopf 1, 63739 Aschaffenburg, Germany.
| | - Dirk Mueller
- Department of Neonatology and Pediatrics, Gesundheit Nordhessen, Mönchebergstraße 41-43, 34125 Kassel, Germany.
| | - Ludwig Patzer
- Department of Pediatric Nephrology, Department of Pediatrics, Krankenhaus Halle Saale, Mauerstr. 5, 06110 Halle Saale, Germany.
| | - Martin Pohl
- Department of Pediatric Nephrology, Department of Pediatrics, University Children 's Hospital Freiburg, Mathildenstr. 1, 79106 Freiburg, Germany.
| | - Barbara Seitz
- KFH Pediatric Kidney Center Munich, Parzivalstr. 16, 80804 Munich, Germany.
| | - Ulrike Treikauskas
- Department of Pediatric Nephrology, Department of Pediatrics, RoMed Kliniken, Pettenkoferstr. 10, 83022 Rosenheim, Germany.
| | - Rodo O von Vigier
- Pediatric Clinic, Wildermeth Children's Hospital, Vogelsang 84, 2502 Biel-Bienne, Switzerland.
| | - William Allen Gahl
- National Genome Research Institute (NHGRI), National Institutes of Health, Medical Genetics Branch, 9000 Rockville Pike, Bethesda, MD 20892, USA.
| | - Katharina Hohenfellner
- Department of Pediatric Nephrology, Department of Pediatrics, RoMed Kliniken, Pettenkoferstr. 10, 83022 Rosenheim, Germany.
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Hohenfellner K, Nießl C, Haffner D, Oh J, Okorn C, Palm K, Schlingmann KP, Wygoda S, Gahl WA. Beneficial effects of starting oral cysteamine treatment in the first 2 months of life on glomerular and tubular kidney function in infantile nephropathic cystinosis. Mol Genet Metab 2022; 136:282-288. [PMID: 35843134 PMCID: PMC9413354 DOI: 10.1016/j.ymgme.2022.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 06/28/2022] [Indexed: 10/17/2022]
Abstract
Nephropathic cystinosis is a rare lysosomal storage disease whose basic defect, impaired transport of cystine out of lysosomes, results in intracellular cystine storage. Affected individuals exhibit renal Fanconi Syndrome in infancy, end-stage kidney disease at approximately 10 years of age, and many other systemic complications. Oral cysteamine therapy mitigates the detrimental effects on glomerular function and prevents most of the late complications of the disease but has not shown benefit with respect to the early tubular damage of cystinosis. This is because cystinosis is generally diagnosed in the second year of life, after the damage to kidney tubular function has already occurred. We longitudinally evaluated 6 infants diagnosed and treated with cysteamine from before 2 months of age. The 4 infants with good compliance with cysteamine and consistently low leucocyte cystine levels maintained normal eGFR values, exhibited only minor degrees of renal Fanconi Syndrome, and maintained normal serum levels of potassium, bicarbonate, phosphate, and calcium without electrolyte or mineral supplementation through 2, 4, 10 and 16 years of age. Thus, renal Fanconi syndrome can be attenuated by early administration of cysteamine and renew the call for molecular-based newborn screening for cystinosis.
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Affiliation(s)
- Katharina Hohenfellner
- Department of Pediatrics, Pediatric Nephrology, RoMed Kliniken, Pettenkoferstr.10, 83022 Rosenheim, Germany.
| | - Christina Nießl
- Institute for Medical Information Processing, Biometry and Epidemiology (IBE), Working group "Biometry in Molecular Medicine", Ludwig-Maximilians-University of Munich, Marchoninistr.15, 81377 Munich, Germany.
| | - Dieter Haffner
- Department of Pediatrics, Department of Pediatric Kidney, Liver and Metabolic Diseases, Medical School, Carl-Neuberg-str.1, 30625 Hannover, Germany.
| | - Jun Oh
- Department of Pediatrics, Pediatric Nephrology, University Center Hamburg/Eppendorf, Martinistr. 52, 20251 Hamburg, Germany.
| | - Christine Okorn
- Department of Pediatrics II, University Hospital of Essen, University of Duisburg-Essen, Hufelandstr. 55, 45147 Essen, Germany.
| | - Katja Palm
- Department of Pediatrics, University Hospital Magdeburg, Leipzigerstr. 44, 39120 Magdeburg, Germany.
| | - Karl-Peter Schlingmann
- Department of General Pediatrics, Pediatric Nephrology, University Children's Hospital Münster, Waldeyerstr.22, 48149 Münster, Germany.
| | - Simone Wygoda
- KFH Pediatric Kidney Center Leipzig, Delitzscherstr. 14, 04129 Leipzig, Germany.
| | - William Allen Gahl
- National Genome Research Institute (NHGRI), National Institutes of Health, Medical Genetics Branch, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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Vill K, Müller-Felber W, Landfarth T, Köppl C, Herzig N, Knerr C, Holla H, Steidle G, Harms E, Hohenfellner K. Neuromuscular conditions and the impact of cystine-depleting therapy in infantile nephropathic cystinosis: A cross-sectional analysis of 55 patients. J Inherit Metab Dis 2022; 45:183-191. [PMID: 34888877 DOI: 10.1002/jimd.12464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/12/2021] [Accepted: 12/07/2021] [Indexed: 11/08/2022]
Abstract
Infantile nephropathic cystinosis (INC) is a rare lysosomal storage disease caused by biallelic mutations in the cystinosin gene, leading to cystine accumulation in various organs. The aim of this cross-sectional study was to investigate neuromuscular complications in a cohort of 55 patients (aged 2.8-41.3 years, median 18.5 years) with INC. Clinical examination, jumping mechanography, clinical neurophysiology, and muscle/nerve ultrasound were performed. Physical performance, measured by mechanography, was below average in all patients. However, this reduction in physical performance was not always detected by conventional muscle power assessment. Twenty-eight percent of patients had mostly mild axial weakness of the neck flexors and/or of the abdominal rectus muscles, the latter often presenting during childhood. One adult patient had generalized muscle weakness. Two patients had evidence of specific neuromuscular conditions, which may not have been directly related to cystinosis. 30% of patients presented with mild, 7% with moderate, and 5% with severe weakness of the intrinsic muscles of the hand. Muscle wasting was more pronounced in the older cystinosis patients with multiple organ complications. Sonographic increase in muscle echogenicity corresponded only with severe weakness. Electromyography of the intrinsic hand muscles, performed in selected patients, showed myopathic, neurogenic, or mixed myopathic-neurogenic abnormalities. A particularly important finding of this study is that the neuromuscular complications were largely independent from both the age of initiation of pharmacological cystine-depleting therapy and from adherence to treatment. Significant correlation was observed between better physical performance in jumping and cysteine levels in leukocytes.
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Affiliation(s)
- Katharina Vill
- Department of Pediatric Neurology and Developmental Medicine, Dr. von Hauner Children's Hospital, LMU - University of Munich, Munich, Germany
| | - Wolfgang Müller-Felber
- Department of Pediatric Neurology and Developmental Medicine, Dr. von Hauner Children's Hospital, LMU - University of Munich, Munich, Germany
| | - Timotheus Landfarth
- Institute for Medical Information Processing, Biometry, and Epidemiology, LMU - University of Munich, Munich, Germany
| | | | - Nadine Herzig
- Schoen Clinic Munich Harlaching, Specialist Centre for Paediatric and Neuro-Orthopaedics, Munich, Germany
| | | | - Heike Holla
- Department of Pediatric Nephrology, Children's Hospital Rosenheim, Rosenheim, Germany
| | | | - Erik Harms
- Formally Chairman (retired) of the Department of Pediatrics, University of Muenster, Münster, Germany
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Hamed DH, Halim RMA, El Attar MM, Soliman NA, Osman HM. Pulmonary dysfunction in children with Cystinosis: single center study, original article. EGYPTIAN PEDIATRIC ASSOCIATION GAZETTE 2022. [DOI: 10.1186/s43054-022-00098-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Cystinosis is a rare autosomal recessive disorder involving lysosomal storage of the amino acid cystine due to a defect in the membrane transport protein, cystinosin. The disease results in intracellular accumulation of cystine in all organs and tissues.
Pulmonary complications targeting the respiratory system occurs commonly in adults who have not received lifelong cysteamine therapy. The respiratory insufficiency is fatal at adulthood. However, little is known about the pulmonary dysfunction in children.
The study included 15 nephropathic cystinosis children to evaluate the pulmonary complications through detailed history taking, clinical examination, chest radiograph and Pulmonary function test (Impulse oscillometry {IOS}).
Results
Out of the cohort of 15 cystinosis patients, 13 patients did not show symptoms suggestive of chest affection. While 1 patient had recurrent Aspiration and 1 patient had history of pneumonia requiring hospital admission. All patients showed normal respiratory rate for age, normal breath sound and normal Chest X-ray finding apart from conical chest configuration.
IOS done showed small airway disease in 12 patients, decreased compliance in 2 patients, while only 1patient had normal IOS.
Conclusion
Small airway affection was detected in most of cystinosis children by means of IOS in spite of the absence of chest manifestations and suggestive history which highlight the importance of respiratory assessment and follow up of cystinosis patients not only by history, and examination but most important pulmonary function tests.
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Muscle and Bone Impairment in Infantile Nephropathic Cystinosis: New Concepts. Cells 2022; 11:cells11010170. [PMID: 35011732 PMCID: PMC8749987 DOI: 10.3390/cells11010170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/28/2021] [Accepted: 01/01/2022] [Indexed: 11/17/2022] Open
Abstract
Cystinosis Metabolic Bone Disease (CMBD) has emerged during the last decade as a well-recognized, long-term complication in patients suffering from infantile nephropathic cystinosis (INC), resulting in significant morbidity and impaired quality of life in teenagers and adults with INC. Its underlying pathophysiology is complex and multifactorial, associating complementary, albeit distinct entities, in addition to ordinary mineral and bone disorders observed in other types of chronic kidney disease. Amongst these long-term consequences are renal Fanconi syndrome, hypophosphatemic rickets, malnutrition, hormonal abnormalities, muscular impairment, and intrinsic cellular bone defects in bone cells, due to CTNS mutations. Recent research data in the field have demonstrated abnormal mineral regulation, intrinsic bone defects, cysteamine toxicity, muscle wasting and, likely interleukin-1-driven inflammation in the setting of CMBD. Here we summarize these new pathophysiological deregulations and discuss the crucial interplay between bone and muscle in INC. In future, vitamin D and/or biotherapies targeting the IL1β pathway may improve muscle wasting and subsequently CMBD, but this remains to be proven.
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10
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Cherqui S. Hematopoietic Stem Cell Gene Therapy for Cystinosis: From Bench-to-Bedside. Cells 2021; 10:3273. [PMID: 34943781 PMCID: PMC8699556 DOI: 10.3390/cells10123273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/31/2022] Open
Abstract
Cystinosis is an autosomal recessive metabolic disease that belongs to the family of lysosomal storage disorders. The gene involved is the CTNS gene that encodes cystinosin, a seven-transmembrane domain lysosomal protein, which is a proton-driven cystine transporter. Cystinosis is characterized by the lysosomal accumulation of cystine, a dimer of cysteine, in all the cells of the body leading to multi-organ failure, including the failure of the kidney, eye, thyroid, muscle, and pancreas, and eventually causing premature death in early adulthood. The current treatment is the drug cysteamine, which is onerous and expensive, and only delays the progression of the disease. Employing the mouse model of cystinosis, using Ctns-/- mice, we first showed that the transplantation of syngeneic wild-type murine hematopoietic stem and progenitor cells (HSPCs) led to abundant tissue integration of bone marrow-derived cells, a significant decrease in tissue cystine accumulation, and long-term kidney, eye and thyroid preservation. To translate this result to a potential human therapeutic treatment, given the risks of mortality and morbidity associated with allogeneic HSPC transplantation, we developed an autologous transplantation approach of HSPCs modified ex vivo using a self-inactivated lentiviral vector to introduce a functional version of the CTNS cDNA, pCCL-CTNS, and showed its efficacy in Ctns-/- mice. Based on these promising results, we held a pre-IND meeting with the Food and Drug Administration (FDA) to carry out the FDA agreed-upon pharmacological and toxicological studies for our therapeutic candidate, manufacturing development, production of the GMP lentiviral vector, design Phase 1/2 of the clinical trial, and filing of an IND application. Our IND was cleared by the FDA on 19 December 2018, to proceed to the clinical trial using CD34+ HSPCs from the G-CSF/plerixafor-mobilized peripheral blood stem cells of patients with cystinosis, modified by ex vivo transduction using the pCCL-CTNS vector (investigational product name: CTNS-RD-04). The clinical trial evaluated the safety and efficacy of CTNS-RD-04 and takes place at the University of California, San Diego (UCSD) and will include up to six patients affected with cystinosis. Following leukapheresis and cell manufacturing, the subjects undergo myeloablation before HSPC infusion. Patients also undergo comprehensive assessments before and after treatment to evaluate the impact of CTNS-RD-04 on the clinical outcomes and cystine and cystine crystal levels in the blood and tissues for 2 years. If successful, this treatment could be a one-time therapy that may eliminate or reduce renal deterioration as well as the long-term complications associated with cystinosis. In this review, we will describe the long path from bench-to-bedside for autologous HSPC gene therapy used to treat cystinosis.
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Affiliation(s)
- Stephanie Cherqui
- Department of Pediatrics, Division of Genetics, University of California, La Jolla, San Diego, CA 92093, USA
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11
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Adult complications of nephropathic cystinosis: a systematic review. Pediatr Nephrol 2021; 36:223-236. [PMID: 32016627 DOI: 10.1007/s00467-020-04487-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/18/2020] [Accepted: 01/20/2020] [Indexed: 01/13/2023]
Abstract
While nephropathic cystinosis is classically thought of as a childhood disease, with improved treatments, patients are more commonly living into adulthood. We performed a systematic review of the literature available on what complications this population faces as it ages. Nearly every organ system is affected in cystinosis, either from the disease itself or from sequelae of kidney transplantation. While cysteamine is known to delay the onset of end-stage kidney disease, its effects on other complications of cystinosis are less well determined. More common adult-onset complications include myopathy, diabetes, and hypothyroidism. Some less common complications, such as neurologic dysfunction, can still have a profound impact on those with cystinosis. Areas for further research in this area include additional study of the impact of cysteamine on the nonrenal manifestations of cystinosis, as well as possible avenues for new and novel treatments.
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12
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Iyob-Tessema H, Wang CS, Kennedy S, Reyes L, Shin S, Greenbaum LA, Hogan J. Grip Strength in Adults and Children with Cystinosis. Kidney Int Rep 2020; 6:389-395. [PMID: 33615064 PMCID: PMC7879123 DOI: 10.1016/j.ekir.2020.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 10/30/2020] [Accepted: 11/17/2020] [Indexed: 11/05/2022] Open
Abstract
Introduction Chronic kidney disease (CKD) is associated with impaired muscle strength. Patients with cystinosis have an increased risk for impaired muscle strength because of early development of CKD and cystinosis-induced myopathy. This study assesses muscle strength in patients with cystinosis and investigates risk factors of decreased muscle strength. Methods Adult and pediatric patients were recruited from Cystinosis Research Network conferences and a large pediatric nephrology clinic between 2017 and 2019. Patients and caregivers completed questionnaires on demographic characteristics, disease course, daily physical activity, and neuromuscular symptoms. Grip strength was assessed using a dynameter and calculated z-scores for age and sex were assessed for associations with patient characteristics. Results We included 76 patients with a mean grip strength z-score of −2.1 (SD, 1.1), which was lower than seen in patients with CKD without cystinosis. Male sex and delayed cysteamine initiation were independently associated with impaired grip strength. Among adults, a low level of physical activity was associated with lower grip strength z score, but no association was found in children. A third of the patients reported neuromuscular symptoms, with swallowing issues associated with lower grip strength. There was no significant correlation between eGFR and grip strength z-score. Conclusion Patients with cystinosis have impaired muscle strength compared with healthy control subjects and patients with CKD. This impairment is greater in male patients and in patients with late initiation of cysteamine therapy and is associated with lower physical activity. Further studies investigating the effect of different types of physical activities, optimizing cysteamine therapy, and other interventions are needed.
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Affiliation(s)
- Helina Iyob-Tessema
- Department of Pediatrics, Emory School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Chia-Shi Wang
- Department of Pediatrics, Emory School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Sabina Kennedy
- Department of Pediatrics, Emory School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Loretta Reyes
- Department of Pediatrics, Emory School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Stella Shin
- Department of Pediatrics, Emory School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Larry A Greenbaum
- Department of Pediatrics, Emory School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Julien Hogan
- Emory Transplant Center, Department of Surgery, Emory School of Medicine, Atlanta, Georgia, USA.,Pediatric Nephology Department, Robert Debré Hospital, Paris, France
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13
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Kushlaf H. Cystinosis myopathy: Searching for optimal clinical outcome measures. Muscle Nerve 2020; 62:652-653. [PMID: 32959378 DOI: 10.1002/mus.27065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 09/06/2020] [Accepted: 09/11/2020] [Indexed: 11/05/2022]
Affiliation(s)
- Hani Kushlaf
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati, Cincinnati, Ohio, USA
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Sadjadi R, Sullivan S, Grant N, Thomas SE, Doyle M, Hammond C, Corre C, Mello N, David WS, Eichler F. Clinical trial readiness study of distal myopathy and dysphagia in nephropathic cystinosis. Muscle Nerve 2020; 62:681-687. [PMID: 32737993 DOI: 10.1002/mus.27039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 07/23/2020] [Accepted: 07/27/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Nephropathic cystinosis is a lysosomal storage disorder with late-onset systemic complications, such as myopathy and dysphagia. Currently employed outcome measures lack sensitivity and responsiveness for dysphagia and myopathy, a limitation to clinical trial readiness. METHODS We evaluated 20 patients with nephropathic cystinosis in two visits over the course of a year to identify outcomes sensitive to detect changes over time. Patients also underwent an expiratory muscle strength training program to assess any effects on aspiration and dysphagia. RESULTS There were significant differences in the Timed Up and Go Test (TUG) and Timed 25-Foot Walk (25-FW) between baseline and 1-y follow-up (P < .05). Maximum expiratory pressure (MEP) and peak cough flow (PCF) significantly improved following respiratory training (P < .05). CONCLUSIONS Improved respiratory outcomes may enhance patients ability to expel aspirated material from the airway, stave off pulmonary sequelae associated with chronic aspiration, and yield an overall improvement in physical health and well-being.
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Affiliation(s)
- Reza Sadjadi
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Stacey Sullivan
- Department of Speech, Language and Swallowing Disorders, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Natalie Grant
- Center for Rare Neurological Diseases, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Susan E Thomas
- Division of Pediatric Nephrology, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, Ann Arbor, Michigan, USA
| | - Maya Doyle
- Department of Social Work, School of Health Sciences, Quinnipiac University, Hamden, Connecticut, USA
| | - Colleen Hammond
- Cystinosis Adult Care Excellence Initiative, Reading, Massachusetts, USA
| | - Camille Corre
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Nicholas Mello
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - William S David
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Florian Eichler
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts, USA
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15
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Topaloglu R, Keser AG, Gülhan B, Ozaltin F, Demir H, Çiftci T, Demir N, Temucin ÇM, Yuce A, Akhan O. Cystinosis beyond kidneys: gastrointestinal system and muscle involvement. BMC Gastroenterol 2020; 20:242. [PMID: 32727395 PMCID: PMC7392712 DOI: 10.1186/s12876-020-01385-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 07/15/2020] [Indexed: 11/10/2022] Open
Abstract
Background Cystinosis is a multisystemic disease resulting from cystine accumulation primarily in kidney and many other tissues. We intended to study the evolution of less commonly seen extrarenal complications of cystinosis in a group of patients who have periods without cysteamine treatment. Methods Gastrointestinal and muscular complications of cystinosis were studied in a group of 21 patients. Results Twenty one patients were included in the study. Among them, 14 were homozygous and 3 were compound heterozygous for CTNS mutations. The median age of diagnosis was 15 months (range; 5 months-14 years) and the mean age at last visit was 11.3 ± 6.5 years. Nine patients (42%) had end stage renal disease at a mean age of 10.6 years (6.5–17 years). Abdominal ultrasonography and portal vein doppler ultrasonography were performed in19 patients, 14 of them (74%) had hepatomegaly, 10 patients (53%) had granular pattern or heterogeneity of liver. Only one patient had high transaminase levels and liver biopsy showed cystine crystals in the liver. Eleven patients (58%) had borderline or increased portal vein minimum and maximum flow velocities. One patient had CK level of 9024 U/L and electromyographic study showed active myopathic involvement. Two patients were found to have gastroesaphageal reflux only and 4 patients were found to have esophageal remnants in addition to reflux. Conclusions In addition to renal functions, extrarenal organs may be affected from cystine accumulation even in childhood, especially in patients who are incompliant to treatment, resulting in complications such as swallowing difficulty, hepatomegaly and portal hypertension.
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Affiliation(s)
- Rezan Topaloglu
- Division of Pediatric Nephrology, Hacettepe University School of Medicine, 06100 Sıhhiye, Ankara, Turkey.
| | | | - Bora Gülhan
- Division of Pediatric Nephrology, Hacettepe University School of Medicine, 06100 Sıhhiye, Ankara, Turkey
| | - Fatih Ozaltin
- Division of Pediatric Nephrology, Hacettepe University School of Medicine, 06100 Sıhhiye, Ankara, Turkey.,Nephrogenetics Laboratory, Hacettepe University School of Medicine, Ankara, Turkey
| | - Hülya Demir
- Division of Pediatric Gastroenterology, Hacettepe University School of Medicine, Ankara, Turkey
| | - Türkmen Çiftci
- Department of Radiology, Hacettepe University School of Medicine, Ankara, Turkey
| | - Numan Demir
- Hacettepe University School of Physiotherapy, Ankara, Turkey
| | - Çağrı Mesut Temucin
- Department of Neurology, Hacettepe University School of Medicine, Ankara, Turkey
| | - Aysel Yuce
- Division of Pediatric Gastroenterology, Hacettepe University School of Medicine, Ankara, Turkey
| | - Okhan Akhan
- Department of Radiology, Hacettepe University School of Medicine, Ankara, Turkey
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16
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Cheung WW, Hao S, Wang Z, Ding W, Zheng R, Gonzalez A, Zhan J, Zhou P, Li S, Esparza MC, Hoffman HM, Lieber RL, Mak RH. Vitamin D repletion ameliorates adipose tissue browning and muscle wasting in infantile nephropathic cystinosis-associated cachexia. J Cachexia Sarcopenia Muscle 2020; 11:120-134. [PMID: 31721480 PMCID: PMC7015252 DOI: 10.1002/jcsm.12497] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 07/30/2019] [Accepted: 08/25/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Ctns-/- mice, a mouse model of infantile nephropathic cystinosis, exhibit hypermetabolism with adipose tissue browning and profound muscle wasting. Ctns-/- mice are 25(OH)D3 and 1,25(OH)2 D3 insufficient. We investigated whether vitamin D repletion could ameliorate adipose tissue browning and muscle wasting in Ctns-/- mice. METHODS Twelve-month-old Ctns-/- mice and wild-type controls were treated with 25(OH)D3 and 1,25(OH)2 D3 (75 μg/kg/day and 60 ng/kg/day, respectively) or an ethylene glycol vehicle for 6 weeks. Serum chemistry and parameters of energy homeostasis were measured. We quantitated total fat mass and studied expression of molecules regulating adipose tissue browning, energy metabolism, and inflammation. We measured lean mass content, skeletal muscle fibre size, in vivo muscle function (grip strength and rotarod activity), and expression of molecules regulating muscle metabolism. We also analysed the transcriptome of skeletal muscle in Ctns-/- mice using RNAseq. RESULTS Supplementation of 25(OH)D3 and 1,25(OH)2 D3 normalized serum concentration of 25(OH)D3 and 1,25(OH)2 D3 in Ctns-/- mice, respectively. Repletion of vitamin D partially or fully normalized food intake, weight gain, gain of fat, and lean mass, improved energy homeostasis, and attenuated perturbations of uncoupling proteins and adenosine triphosphate content in adipose tissue and muscle in Ctns-/- mice. Vitamin D repletion attenuated elevated expression of beige adipose cell biomarkers (UCP-1, CD137, Tmem26, and Tbx1) as well as aberrant expression of molecules implicated in adipose tissue browning (Cox2, Pgf2α, and NF-κB pathway) in inguinal white adipose tissue in Ctns-/- mice. Vitamin D repletion normalized skeletal muscle fibre size and improved in vivo muscle function in Ctns-/- mice. This was accompanied by correcting the increased muscle catabolic signalling (increased protein contents of IL-1β, IL-6, and TNF-α as well as an increased gene expression of Murf-2, atrogin-1, and myostatin) and promoting the decreased muscle regeneration and myogenesis process (decreased gene expression of Igf1, Pax7, and MyoD) in skeletal muscles of Ctns-/- mice. Muscle RNAseq analysis revealed aberrant gene expression profiles associated with reduced muscle and neuron regeneration, increased energy metabolism, and fibrosis in Ctns-/- mice. Importantly, repletion of 25(OH)D3 and 1,25(OH)2 D3 normalized the top 20 differentially expressed genes in Ctns-/- mice. CONCLUSIONS We report the novel findings that correction of 25(OH)D3 and 1,25(OH)2 D3 insufficiency reverses cachexia and may improve quality of life by restoring muscle function in an animal model of infantile nephropathic cystinosis. Mechanistically, vitamin D repletion attenuates adipose tissue browning and muscle wasting in Ctns-/- mice via multiple cellular and molecular mechanisms.
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Affiliation(s)
- Wai W. Cheung
- Pediatric NephrologyRady Children's Hospital—San Diego, University of California, San DiegoSan DiegoCAUSA
| | - Sheng Hao
- Department of Nephrology and RheumatologyShanghai Children's Hospital, Shanghai Jiao Tong UniversityShanghaiChina
| | - Zhen Wang
- Department of PediatricsShanghai General Hospital, Shanghai Jiao Tong UniversityShanghaiChina
| | - Wei Ding
- Division of NephrologyShanghai 9th People's Hospital, Shanghai Jiao Tong UniversityShanghaiChina
| | - Ronghao Zheng
- Department of Pediatric Nephrology, Rheumatology, and ImmunologyMaternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Alex Gonzalez
- Pediatric NephrologyRady Children's Hospital—San Diego, University of California, San DiegoSan DiegoCAUSA
| | | | - Ping Zhou
- Department of PediatricsThe 2 Hospital of Harbin Medical UniversityHarbinChina
| | - Shiping Li
- College of Bioscience and BiotechnologyYangzhou UniversityYangzhouChina
| | - Mary C. Esparza
- Department of Orthopedic SurgeryUniversity of California, San DiegoSan DiegoCAUSA
| | - Hal M. Hoffman
- Department of PediatricsUniversity of California, San DiegoSan DiegoCAUSA
| | - Richard L. Lieber
- Department of Orthopedic SurgeryUniversity of California, San DiegoSan DiegoCAUSA
- Rehabilitation Institute of ChicagoChicagoILUSA
| | - Robert H. Mak
- Pediatric NephrologyRady Children's Hospital—San Diego, University of California, San DiegoSan DiegoCAUSA
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17
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Sadjadi R, Sullivan S, Grant N, Thomas SE, Doyle M, Hammond C, Duong R, Corre C, David W, Eichler F. Clinical myopathy in patients with nephropathic cystinosis. Muscle Nerve 2019; 61:74-80. [PMID: 31588568 DOI: 10.1002/mus.26726] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 09/16/2019] [Accepted: 09/17/2019] [Indexed: 12/20/2022]
Abstract
BACKGROUND Nephropathic cystinosis is a lysosomal storage disorder. Patient survival years after renal transplantation has revealed systemic complications including distal myopathy and dysphagia. METHODS We evaluated 20 adult patients with nephropathic cystinosis using patient-reported and clinical outcome measures. Standard motor measures, video fluoroscopy swallow studies, and tests of respiratory function were performed. We also used Rasch analysis of an initial survey to design a 16-item survey focused on upper and lower extremity function, which was completed by 31 additional patients. RESULTS Distal myopathy and dysphagia were common in patients with nephropathic cystinosis. Muscle weakness ranges from mild involvement of intrinsic hand muscles to prominent distal greater than proximal weakness and contractures. CONCLUSIONS In addition to further characterization of underlying dysphagia and muscle weakness, we propose a new psychometrically devised, disease specific, functional outcome measures for distal myopathy in patients with nephropathic cystinosis.
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Affiliation(s)
- Reza Sadjadi
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Massachusetts
| | - Stacey Sullivan
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Natalie Grant
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Massachusetts
| | - Susan E Thomas
- Division of Pediatric Nephrology, Department of Pediatrics and Communicable Diseases, University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Maya Doyle
- Department of Social Work, School of Health Sciences, Quinnipiac University, Hamden, Connecticut
| | - Colleen Hammond
- Cystinosis Adult Care Excellence Initiative, Reading, Massachusetts
| | - Rachel Duong
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Massachusetts
| | - Camille Corre
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Massachusetts
| | - William David
- Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
| | - Florian Eichler
- Center for Rare Neurological Diseases, Department of Neurology, Massachusetts General Hospital, Massachusetts
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Abstract
Nephropathic cystinosis is an autosomal recessive lysosomal disease in which cystine cannot exit the lysosome to complete its degradation in the cytoplasm, thus accumulating in tissues. Some patients develop a distal myopathy involving mainly hand muscles. Myopathology descriptions from only 5 patients are available in the literature. We present a comprehensive clinical, pathological and genetic description of 3 patients from 2 families with nephropathic cystinosis. Intrafamiliar variability was detected in one family in which one sibling developed a severe distal myopathy while the other sibling did not show any signs of skeletal muscle involvement. One of the patients was on treatment with Cysteamine for over 12 years but still developed the usual complications of nephropathic cystinosis in his twenties. Novel pathological findings consisting in sarcoplasmic deposits reactive for slow myosin were identified. Three previously known and one novel mutation are reported. Nephropathic cystinosis should be included in the differential diagnosis of distal myopathies in those with early renal failure. Novel clinical and pathological features are reported here contributing to the characterization of the muscle involvement in nephropathic cystinosis.
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20
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Abstract
PURPOSE OF REVIEW Over the past few decades, cystinosis, a rare lysosomal storage disorder, has evolved into a treatable metabolic disease. The increasing understanding of its pathophysiology has made cystinosis a prototype disease, delivering new insights into several fundamental biochemical and cellular processes. RECENT FINDINGS In this review, we aim to provide an overview of the latest advances in the pathogenetic, clinical, and therapeutic aspects of cystinosis. SUMMARY The development of alternative therapeutic monitoring strategies and new systemic and ocular cysteamine formulations might improve outcome of cystinosis patients in the near future. With the dawn of stem cell based therapy and new emerging gene-editing technologies, novel tools have become available in the search for a cure for cystinosis.
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Cherqui S, Courtoy PJ. The renal Fanconi syndrome in cystinosis: pathogenic insights and therapeutic perspectives. Nat Rev Nephrol 2016; 13:115-131. [PMID: 27990015 DOI: 10.1038/nrneph.2016.182] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cystinosis is an autosomal recessive metabolic disease that belongs to the family of lysosomal storage disorders. It is caused by a defect in the lysosomal cystine transporter, cystinosin, which results in an accumulation of cystine in all organs. Despite the ubiquitous expression of cystinosin, a renal Fanconi syndrome is often the first manifestation of cystinosis, usually presenting within the first year of life and characterized by the early and severe dysfunction of proximal tubule cells, highlighting the unique vulnerability of this cell type. The current therapy for cystinosis, cysteamine, facilitates lysosomal cystine clearance and greatly delays progression to kidney failure but is unable to correct the Fanconi syndrome. This Review summarizes decades of studies that have fostered a better understanding of the pathogenesis of the renal Fanconi syndrome associated with cystinosis. These studies have unraveled some of the early molecular changes that occur before the onset of tubular atrophy and identified a role for cystinosin beyond cystine transport, in endolysosomal trafficking and proteolysis, lysosomal clearance, autophagy and the regulation of energy balance. These studies have also led to the identification of new potential therapeutic targets and here, we outline the potential role of stem cell therapy for cystinosis and provide insights into the mechanism of haematopoietic stem cell-mediated kidney protection.
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Affiliation(s)
- Stephanie Cherqui
- Department of Pediatrics, Division of Genetics, University of California San Diego, 9500 Gilman Drive, MC 0734, La Jolla, California 92093-0734, USA
| | - Pierre J Courtoy
- Cell biology, de Duve Institute and Université catholique de Louvain, UCL-Brussels, 75 Avenue Hippocrate, B-1200 Brussels, Belgium
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Controversies and research agenda in nephropathic cystinosis: conclusions from a “Kidney Disease: Improving Global Outcomes” (KDIGO) Controversies Conference. Kidney Int 2016; 89:1192-203. [DOI: 10.1016/j.kint.2016.01.033] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 01/22/2016] [Accepted: 01/28/2016] [Indexed: 01/19/2023]
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Abstract
Cystinosis is a rare, autosomal recessive inherited lysosomal storage disease. It is the most frequent and potentially treatable cause of the inherited renal Fanconi syndrome. If left untreated, renal function rapidly deteriorates towards end-stage renal disease by the end of the first decade of life. Due to its rarity and non-specific presentation, the entity is often not promptly recognized resulting in delayed diagnosis. Two major milestones in cystinosis management, cystine-depleting therapy with cysteamine and renal allograft transplantation, have had a considerable impact on the natural history and prognosis of cystinosis patients. However, due to its significant side effects and a strict 6-hourly dosing regimen, non-adherence to the immediate release of cysteamine bitartrate formulation (Cystagon®) is a major issue that might affect long-term outcome. Recently, a new twice-daily administered delayed-release enteric-coated formula of cysteamine bitartrate (Procysbi(TM)) has been approved by the European Medical Agency for the treatment of cystinosis, and has been shown to be safe and effective. This delayed-release cysteamine has the potential to improve compliance and hence prognosis, through its better dosing regimen, positive impact on quality of life and possibly less side-effects, and is now tested in an ongoing long-term clinical trial. Longer survival of patients with cystinosis makes transition from pediatric to adult-oriented care another challenge in cystinosis management and requires an extended multidisciplinary approach.
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Affiliation(s)
- Koenraad R P Veys
- a Department of Pediatrics, Pediatric Nephrology , University Hospitals Leuven , Belgium
| | - Martine T P Besouw
- b Department of Pediatric Nephrology , University Hospital Ghent , Belgium
| | | | - Maria Van Dyck
- a Department of Pediatrics, Pediatric Nephrology , University Hospitals Leuven , Belgium
| | - Ingele Casteels
- c Department of Ophthalmology , University Hospitals Leuven , Belgium
| | - Elena N Levtchenko
- a Department of Pediatrics, Pediatric Nephrology , University Hospitals Leuven , Belgium
- d Department of Growth & Regeneration , Katholieke Universiteit Leuven , Belgium
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Elmonem MA, Veys KR, Soliman NA, van Dyck M, van den Heuvel LP, Levtchenko E. Cystinosis: a review. Orphanet J Rare Dis 2016; 11:47. [PMID: 27102039 PMCID: PMC4841061 DOI: 10.1186/s13023-016-0426-y] [Citation(s) in RCA: 144] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 04/15/2016] [Indexed: 01/01/2023] Open
Abstract
Cystinosis is the most common hereditary cause of renal Fanconi syndrome in children. It is an autosomal recessive lysosomal storage disorder caused by mutations in the CTNS gene encoding for the carrier protein cystinosin, transporting cystine out of the lysosomal compartment. Defective cystinosin function leads to intra-lysosomal cystine accumulation in all body cells and organs. The kidneys are initially affected during the first year of life through proximal tubular damage followed by progressive glomerular damage and end stage renal failure during mid-childhood if not treated. Other affected organs include eyes, thyroid, pancreas, gonads, muscles and CNS. Leucocyte cystine assay is the cornerstone for both diagnosis and therapeutic monitoring of the disease. Several lines of treatment are available for cystinosis including the cystine depleting agent cysteamine, renal replacement therapy, hormonal therapy and others; however, no curative treatment is yet available. In the current review we will discuss the most important clinical features of the disease, advantages and disadvantages of the current diagnostic and therapeutic options and the main topics of future research in cystinosis.
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Affiliation(s)
- Mohamed A Elmonem
- Department of Pediatric Nephrology & Growth and Regeneration, University Hospitals Leuven & KU Leuven, UZ Herestraat 49-3000, Leuven, Belgium.,Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo, Egypt
| | - Koenraad R Veys
- Department of Pediatric Nephrology & Growth and Regeneration, University Hospitals Leuven & KU Leuven, UZ Herestraat 49-3000, Leuven, Belgium
| | - Neveen A Soliman
- Department of Pediatrics, Center of Pediatric Nephrology and Transplantation (CPNT), Faculty of Medicine, Cairo University, Cairo, Egypt.,EGORD, Egyptian group of orphan renal diseases, Cairo, Egypt
| | - Maria van Dyck
- Department of Pediatric Nephrology & Growth and Regeneration, University Hospitals Leuven & KU Leuven, UZ Herestraat 49-3000, Leuven, Belgium
| | - Lambertus P van den Heuvel
- Department of Pediatric Nephrology & Growth and Regeneration, University Hospitals Leuven & KU Leuven, UZ Herestraat 49-3000, Leuven, Belgium.,Department of Pediatric Nephrology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Elena Levtchenko
- Department of Pediatric Nephrology & Growth and Regeneration, University Hospitals Leuven & KU Leuven, UZ Herestraat 49-3000, Leuven, Belgium.
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La cystinose chez l’adulte : une maladie systémique. Nephrol Ther 2015; 11:152-9. [DOI: 10.1016/j.nephro.2014.12.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Revised: 12/15/2014] [Accepted: 12/15/2014] [Indexed: 11/23/2022]
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Cistinosis en pacientes adolescentes y adultos: Recomendaciones para la atención integral de la cistinosis. Nefrologia 2015. [DOI: 10.1016/j.nefro.2015.05.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Ariceta G, Camacho JA, Fernández-Obispo M, Fernández-Polo A, Gamez J, García-Villoria J, Lara Monteczuma E, Leyes P, Martín-Begué N, Oppenheimer F, Perelló M, Morell GP, Torra R, Santandreu AV, Güell A. Cystinosis in adult and adolescent patients: Recommendations for the comprehensive care of cystinosis. Nefrologia 2015; 35:304-321. [PMID: 26523297 DOI: 10.1016/j.nefroe.2015.06.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023] Open
Abstract
INTRODUCTION Cystinosis is a rare lysosomal systemic disease that mainly affects the kidney and the eye. Patients with cystinosis begin renal replacement therapy during the first decade of life in absence of treatment. Prognosis of cystinosis depends on early diagnosis, and prompt starting and good compliance with cysteamine treatment. Kidney disease progression, extra-renal complications and shorter life expectancy are more pronounced in those patients that do not follow treatment. The objective of this work was to elaborate recommendations for the comprehensive care of cystinosis and the facilitation of patient transition from paediatric to adult treatment, based on clinical experience. The goal is to reduce the impact of the disease, and to improve patient quality of life and prognosis. METHODS Bibliographic research and consensus meetings among a multidisciplinary professional team of experts in the clinical practice, with cystinotic patients (T-CiS.bcn group) from 5 hospitals located in Barcelona. RESULTS This document gathers specific recommendations for diagnosis, treatment and multidisciplinary follow-up of cystinotic patients in the following areas: nephrology, dialysis,renal transplant, ophthalmology, endocrinology, neurology, laboratory, genetic counselling,nursing and pharmacy. CONCLUSIONS A reference document for the comprehensive care of cystinosis represents a support tool for health professionals who take care of these patients. It is based on the following main pillars: (a) a multi-disciplinary approach, (b) appropriate disease monitoring and control of intracellular cystine levels in leukocytes, (c) the importance of adherence to treatment with cysteamine, and (d) the promotion of patient self-care by means of disease education programmes. All these recommendations will lead us, in a second phase, to create a coordinated transition model between paediatric and adult care services which will contemplate the specific needs of cystinosis.
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El-Naggari MA, Elnour I, Al-Kindy H, Al-Shahrabally A, Abdelmogheth AA. Successful management of a neglected case of nephropathic cystinosis. Sultan Qaboos Univ Med J 2014; 14:e245-e248. [PMID: 24790750 PMCID: PMC3997544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Revised: 12/30/2013] [Accepted: 01/26/2014] [Indexed: 06/03/2023] Open
Abstract
Cystinosis is a rare metabolic disorder characterised by lysosomal cystine accumulation leading to multi-organ damage; clinically, the kidneys are the first organ affected. Respiratory insufficiency caused by overall respiratory muscle myopathy is a life-threatening complication. Treatment with cysteamine should be initiated rapidly and continued lifelong to prolong renal function and protect the extra-renal organs. We report the case of a four-year-old Omani girl, diagnosed with infantile nephropathic cystinosis at 21 months. Cysteamine was prescribed but with no compliance to medications. She presented to the Child Health Department of Sultan Qaboos University Hospital, Oman, two years later with severe failure to thrive, electrolyte disturbance and respiratory failure. The hypoventilation and early respiratory dysfunction, due to intercostal and diaphragm myopathy, was treated by non-invasive positive-pressure ventilation. The patient was discharged after four months of intensive rehabilitation with no ventilator support. No standard treatment options have yet been established for respiratory dysfunction in cystinosis.
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Abstract
A 26-year-old male with nephropathic cystinosis treated with cysteamine and renal transplantation presented for evaluation of multiple sclerotic bone lesions, which were an incidental finding on chest computerized tomography. These lesions were in a pattern consistent with osteoblastic metastases. He did not have a history of clinically significant hyperparathyroidism or cytopenias either preceding or following his transplant. Bone and tumor markers (including alkaline phosphatase and calcium) were all normal. A percutaneous bone biopsy of the lesions showed changes compatible with cystine deposition. Our case demonstrates that sclerotic bone lesions can be a feature of cystinosis in patients with normal parathyroid function and that significant bone marrow infiltration with cystine can be present even in the absence of cytopenias.
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Nesterova G, Gahl WA. Cystinosis: the evolution of a treatable disease. Pediatr Nephrol 2013; 28:51-9. [PMID: 22903658 PMCID: PMC3505515 DOI: 10.1007/s00467-012-2242-5] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 06/07/2012] [Accepted: 06/08/2012] [Indexed: 11/01/2022]
Abstract
Cystinosis is a rare autosomal recessive disorder involving lysosomal storage of the amino acid cystine due to a defect in the membrane transport protein, cystinosin. Since the introduction of kidney transplants and the availability of cystine-depleting medical therapy, this previously fatal disease was transformed into a treatable disorder. Renal allografts and medical therapy targeting the basic metabolic defect have altered the natural hisotry of cystinosis so drastically that patients have a life expectancy extending past 50 years. Consequently, early diagnosis and appropriate therapy are critically important. In this article, we offer a review of the manifestations of cystinosis, including the proximal tubular dysfunction of renal Fanconi syndrome, and discuss the prevention and treatment of the disorder's systemic complications. We focus on the nephropathic forms of cystinosis, aiming to assist nephrologists and other physicians to develop early recognition and appropriate management of cystinosis patients.
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Affiliation(s)
- Galina Nesterova
- NHGRI, Medical Biochemical Genetic Section, National Institutes of Health, Bethesda, MD, USA.
| | - William A. Gahl
- NHGRI, Medical Biochemical Genetic Section, National Institutes of Health, Bethesda, MD USA
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Taranta A, Petrini S, Citti A, Boldrini R, Corallini S, Bellomo F, Levtchenko E, Emma F. Distribution of cystinosin-LKG in human tissues. Histochem Cell Biol 2012; 138:351-63. [PMID: 22544350 DOI: 10.1007/s00418-012-0958-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2012] [Indexed: 12/31/2022]
Abstract
Nephropathic cystinosis is multisystemic progressive disorder caused by mutations of CTNS gene that encodes for the lysosomal cystine co-transporter cystinosin, and for a less abundant isoform termed cystinosin-LKG, which is expressed in not only lysosomes but also other cell compartments. To overcome the absence of high-quality antibodies against cystinosin, we have obtained a rabbit antiserum against cystinosin-LKG and have analyzed in human tissues the expression of the two known cystinosin isoforms by RT-PCR, and the expression of cystinosin-LKG by immunohistochemistry. In most tissues, CTNS-LKG represents 5-20 % of CTNS transcripts, with the exception of the testis that expresses both isoforms in equal proportions. Cystinosin-LKG was found to be highly expressed in renal tubular cells, pancreatic islets of Langerhans, Leydig cells of the testis, mucoserous glands of the bronchial wall, melanocytes and keratinocytes. These results are parallel with many features of cystinosis, such as early onset Fanconi syndrome, male infertility, diabetes mellitus and hypopigmentation. Intermediate expression levels were of the LKG isoform observed in the gastro-intestinal tract and thyroid glands; low levels of expression were observed in the brain, skeletal and cardiac muscles.
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Affiliation(s)
- Anna Taranta
- Division of Nephrology, Department of Nephrology and Urology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
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Brodin-Sartorius A, Tête MJ, Niaudet P, Antignac C, Guest G, Ottolenghi C, Charbit M, Moyse D, Legendre C, Lesavre P, Cochat P, Servais A. Cysteamine therapy delays the progression of nephropathic cystinosis in late adolescents and adults. Kidney Int 2011; 81:179-89. [PMID: 21900880 DOI: 10.1038/ki.2011.277] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Nephropathic cystinosis is a multisystem autosomal recessive disease caused by cystine accumulation, which is usually treated by oral cysteamine. In order to determine long-term effects of this therapy, we enrolled 86 adult patients (mean age 26.7 years) diagnosed with nephropathic cystinosis, 75 of whom received cysteamine. Therapy was initiated at a mean age of 9.9 years with a mean duration of 17.4 years. By last follow-up, 78 patients had end-stage renal disease (mean age 11.1 years), 62 had hypothyroidism (mean age 13.4), 48 developed diabetes (mean age 17.1 years), and 32 had neuromuscular disorders (mean age 23.3 years). Initiating cysteamine therapy before 5 years of age significantly decreased the incidence and delayed the onset of end-stage renal disease, and significantly delayed the onset of hypothyroidism, diabetes, and neuromuscular disorders. The development of diabetes and hypothyroidism was still significantly delayed, however, in patients in whom therapy was initiated after 5 years of age, compared with untreated patients. The life expectancy was significantly improved in cysteamine-treated versus untreated patients. Thus, cysteamine decreases and delays the onset of complications and improves life expectancy in cystinosis. Hence, cysteamine therapy should be introduced as early as possible during childhood and maintained lifelong.
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Cystinosis: practical tools for diagnosis and treatment. Pediatr Nephrol 2011; 26:205-15. [PMID: 20734088 PMCID: PMC3016220 DOI: 10.1007/s00467-010-1627-6] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Revised: 07/05/2010] [Accepted: 07/07/2010] [Indexed: 02/07/2023]
Abstract
Cystinosis is the major cause of inherited Fanconi syndrome, and should be suspected in young children with failure to thrive and signs of renal proximal tubular damage. The diagnosis can be missed in infants, because not all signs of renal Fanconi syndrome are present during the first months of life. In older patients cystinosis can mimic idiopathic nephrotic syndrome due to focal and segmental glomerulosclerosis. Measuring elevated white blood cell cystine content is the corner stone for the diagnosis. The diagnosis is confirmed by molecular analysis of the cystinosin gene. Corneal cystine crystals are invariably present in all patients with cystinosis after the age of 1 year. Treatment with the cystine depleting drug cysteamine should be initiated as soon as possible and continued lifelong to prolong renal function survival and protect extra-renal organs. This educational feature provides practical tools for the diagnosis and treatment of cystinosis.
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Bassim CW, Gautam P, Domingo DL, Balog JZ, Guadagnini JP, Gahl WA, Hart TC. Craniofacial and dental findings in cystinosis. Oral Dis 2010; 16:488-95. [PMID: 20233313 DOI: 10.1111/j.1601-0825.2010.01662.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Cystinosis is a rare autosomal recessive lysosomal storage disorder with developmental and mineralization anomalies as part of its clinical presentation. The objective of this study was to provide the first systematic assessment of the craniofacial and dental characteristics associated with cystinosis. STUDY DESIGN Oral and radiographic evaluations were performed on 73 patients with cystinosis. Analyses of cephalometry (n = 20), taurodontism (n = 47), caries (n = 47), enamel defects (n = 48), soft tissue anomalies (n = 48), and dental age (n = 41) were performed on the cystinosis group, and compared with age- and sex-comparable controls or standards. RESULTS Cystinosis patients manifested relative mandibular deficiency, an increased facial height, and a reduced airway space. Taurodontism and enamel defects were significantly more prevalent in cystinosis patients compared with controls (P < 0.0001 and P = 0.027, respectively). Children (aged <15 years) with cystinosis also demonstrated a significant delay, of almost 9 months, of their dental development (P < 0.001). CONCLUSION Novel craniofacial and dental features are associated with cystinosis. Craniofacial deficiencies may influence the swallowing and respiratory complications seen in cystinosis. Renal pathology and associated mineral imbalance may explain the dental root and enamel anomalies found in cystinosis patients; the developmental delays in cystinosis include delayed dental formation.
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Affiliation(s)
- C W Bassim
- National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.
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DeVilliers P, Gutta R, Szymela VF. Cystinosis, Fanconi syndrome, and odontogenic cysts. ACTA ACUST UNITED AC 2008; 106:866-71. [PMID: 18926732 DOI: 10.1016/j.tripleo.2008.08.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Revised: 07/31/2008] [Accepted: 08/14/2008] [Indexed: 10/21/2022]
Abstract
Cystinosis is a multisystemic genetic storage disorder characterized by a mutation in the transporter system of cystine. The disease particularly affects the renal system by causing deposition of cystine crystals leading to, if untreated, Fanconi syndrome and end-stage renal disease. This disease also affects the ocular system, central nervous system, endocrine system, hepatobiliary system, and musculoskeletal system. We present the first case of cystine crystal deposition within an odontogenic cyst, confirmed by the correlation of the clinical, radiographic, and histologic findings on this patient.
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Affiliation(s)
- Patricia DeVilliers
- Department of Anatomic Pathology, University of Alabama, Birmingham, Alabama 35249, USA.
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Nesterova G, Gahl W. Nephropathic cystinosis: late complications of a multisystemic disease. Pediatr Nephrol 2008; 23:863-78. [PMID: 18008091 DOI: 10.1007/s00467-007-0650-8] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 09/24/2007] [Accepted: 09/24/2007] [Indexed: 11/29/2022]
Abstract
Cystinosis is a rare autosomal recessive disorder due to impaired transport of cystine out of cellular lysosomes. Its estimated incidence is 1 in 100,000 live births. End-stage renal disease (ESRD) is the most prominent feature of cystinosis and, along with dehydration and electrolyte imbalance due to renal tubular Fanconi syndrome, has accounted for the bulk of deaths from this disorder. Prior to renal transplantation and cystine-depleting therapy with cysteamine for children with nephropathic cystinosis, their lifespan was approximately 10 years. Now, cystinotic patients have survived through their fifth decade, but the unremitting accumulation of cystine has created significant non-renal morbidity and mortality. In this article we review the classic presentation of nephropathic cystinosis and the natural history, diagnosis, and treatment of the disorder's systemic involvement. We also emphasize the role of oral cysteamine therapy in preventing the late complications of cystinosis.
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Affiliation(s)
- Galina Nesterova
- Section on Human Biochemical Genetics, Human Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-1851, USA
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O'Brien K, Hussain N, Warady BA, Kleiner DE, Kleta R, Bernardini I, Heller T, Gahl WA. Nodular regenerative hyperplasia and severe portal hypertension in cystinosis. Clin Gastroenterol Hepatol 2006; 4:387-94. [PMID: 16527704 DOI: 10.1016/j.cgh.2005.12.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Cystinosis is a rare autosomal-recessive disorder characterized by the intralysosomal accumulation of cystine, which is responsible for widespread tissue destruction. Liver biopsy specimens of patients with cystinosis show cystine crystal formation in Kupffer cells. However, significant liver disease and portal hypertension is not a common complication of cystinosis. We report the case histories of 2 young men with poorly treated nephropathic cystinosis who developed noncirrhotic portal hypertension with evidence of nodular regenerative hyperplasia (NRH). METHODS Liver biopsy examinations, upper and lower endoscopy with biopsy examination, imaging studies, venous pressure measurements, and laboratory investigations were used to evaluate the causes of the liver disease and portal hypertension. RESULTS Histologic examination of liver biopsy specimens from both patients showed changes characteristic of NRH with portal hypertension documented by measurement of pressure gradients. In addition, endoscopy in the first patient showed varices and portal hypertensive gastropathy. CONCLUSIONS NRH was confirmed by histologic examination of the liver in both patients and is the likely cause of their portal hypertension. NRH may represent a rare, late complication of cystinosis, although the mechanism remains undefined.
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Affiliation(s)
- Kevin O'Brien
- Section on Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland 20892-1851, USA
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Ueda M, O'Brien K, Rosing DR, Ling A, Kleta R, McAreavey D, Bernardini I, Gahl WA. Coronary artery and other vascular calcifications in patients with cystinosis after kidney transplantation. Clin J Am Soc Nephrol 2006; 1:555-62. [PMID: 17699259 DOI: 10.2215/cjn.01431005] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Cystinosis, an autosomal recessive disorder of lysosomal cystine accumulation, results from mutations in the CTNS gene that encodes the lysosomal cystine transporter, cystinosin. Renal tubular Fanconi syndrome occurs in infancy, followed by rickets, growth retardation, photophobia, and renal failure, which requires renal transplantation at approximately 10 yr of age. Treatment with cysteamine decreases cellular cystine levels, retards renal deterioration, and allows for normal growth. Patients with a history of inadequate cystine depletion therapy may survive, after renal transplantation, into the third to fifth decades but will experience other, extrarenal complications of the disease. Routine chest and head computed tomography scans of 41 posttransplantation patients with cystinosis were reviewed for vascular calcification. The radiologic procedures had been performed to examine lung and brain parenchyma, so there was little ascertainment bias. Thirteen of the 41 patients had vascular calcification, including 11 with coronary artery calcification. One 25-yr-old man required three-vessel coronary artery bypass graft surgery. There were no significant differences between the 13 patients with calcification and the 28 without calcification in the following parameters: Time on dialysis, frequency of transplantation, hypertension, hypercholesterolemia, homozygosity for the 57-kb deletion in CTNS, serum creatinine, and calcium-phosphate product. However, the finding of vascular calcification correlated directly with duration of life without cysteamine therapy and inversely with duration of life under good cystine-depleting therapy. The accumulation of intracellular cystine itself maybe a risk factor for vascular calcifications, and older patients with cystinosis should be screened for this complication.
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Affiliation(s)
- Masako Ueda
- Section on Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD 20892-1851, USA
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Sonies BC, Almajid P, Kleta R, Bernardini I, Gahl WA. Swallowing dysfunction in 101 patients with nephropathic cystinosis: benefit of long-term cysteamine therapy. Medicine (Baltimore) 2005; 84:137-146. [PMID: 15879904 DOI: 10.1097/01.md.0000164204.00159.d4] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Nephropathic cystinosis is a rare, autosomal recessive lysosomal storage disorder caused by mutations in the CTNS gene that codes for a cystine transporter in the lysosomal membrane. Affected patients store 50-100 times the normal amounts of cystine in their cells, and suffer renal tubular and glomerular disease, growth retardation, photophobia, and other systemic complications, including a myopathy and swallowing dysfunction. Using videofluoroscopy and ultrasound examinations, we assessed the swallowing function of 101 patients with nephropathic cystinosis on their most recent admission to the National Institutes of Health Clinical Center between 1987 and 2004. These patients ranged in age from 6 to 45 years; more than half had significant complaints of swallowing difficulty. On examination of barium swallow, the oral, pharyngeal, and esophageal phases of swallowing were abnormal in 24%, 51%, and 73% of patients, respectively. The frequency of dysfunction increased with age for each phase of swallowing. Both the Swallowing Severity Score (a measure of dysfunction on barium swallow) and the Oral Muscle Composite Score (a reflection of vocal strength, oral-facial movement, and tongue and lip function) increased (that is, worsened) with the number of years that a patient was not receiving treatment with cysteamine, the cystine-depleting agent of choice in cystinosis. The severity scores decreased with the number of years on cysteamine therapy. The Swallowing Severity Score varied directly with the severity of muscle disease, but was not correlated with the presence or absence of the 57-kb CTNS deletion that commonly occurs in nephropathic cystinosis patients. We conclude that swallowing dysfunction in cystinosis presents a risk of fatal aspiration, correlates with the presence of muscle atrophy, and, based on cross-sectional data, increases in frequency with age and number of years without cysteamine treatment. Cystine-depleting therapy with cysteamine should be considered the treatment of choice for both pre- and posttransplant cystinosis patients.
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Affiliation(s)
- Barbara C Sonies
- From Oral Motor Function Section (BCS, PA), Physical Disabilities Branch, Rehabilitation Medicine Department, Warren Grant Magnuson Clinical Center; Section on Human Biochemical Genetics (RK, IB, WAG), Medical Genetics Branch, National Human Genome Research Institute; and Intramural Office of Rare Diseases (RK), Office of the Director; National Institutes of Health, Bethesda, Maryland
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Kleta R, Gahl WA. Pharmacological treatment of nephropathic cystinosis with cysteamine. Expert Opin Pharmacother 2004; 5:2255-62. [PMID: 15500372 DOI: 10.1517/14656566.5.11.2255] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Cystinosis, clinically recognised since 1903, is an autosomal recessive lysosomal storage disease caused by mutations in CTNS. This gene codes for a lysosomal cystine transporter, whose absence leads to intracellular cystine crystals, widespread cellular destruction, renal Fanconi syndrome in infancy, renal glomerular failure in later childhood and other systemic complications. Before the availability of kidney transplantation, patients affected with cystinosis uniformly died during childhood. After solid organ transplantations became successful in the 1960s, cystinosis patients survived, but eventually developed life-threatening consequences of the disease (e.g., swallowing disorders). Since the introduction of cysteamine into the pharmacological management of cystinosis, well-treated adolescent and young adult patients have experienced normal growth and maintenance of renal glomerular function. Oral cysteamine therapy is given at doses of 60 - 90 mg/kg/day q.i.d. every 6 h, and generally achieves approximately 90% depletion of cellular cystine, as measured in circulating leucocytes. Cysteamine (and kidney transplantation) have commuted the death sentence of cystinosis into a nearly normal life with a chronic disease. Because treatment with oral cysteamine can prevent, or significantly delay, the complications of cystinosis, early and accurate diagnosis, as well as proper treatment, is critical.
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Affiliation(s)
- Robert Kleta
- NHGRI, Building 10, Room 10C-107, MSC 1851, 10 Center Drive, Bethesda, MD 20892, USA.
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Dogulu CF, Tsilou E, Rubin B, Fitzgibbon EJ, Kaiser-Kupper MI, Rennert OM, Gahl WA. Idiopathic intracranial hypertension in cystinosis. J Pediatr 2004; 145:673-8. [PMID: 15520772 DOI: 10.1016/j.jpeds.2004.06.080] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To report a high frequency of idiopathic intracranial hypertension (IIH) in patients with cystinosis and to speculate on the relationship between these two disorders. STUDY DESIGN Retrospective case series and review of the literature regarding risk factors for the development of IIH in cystinosis. RESULTS Eight patients with cystinosis had documented papilledema, normal neuroimaging of the brain, cerebrospinal fluid (CSF) opening pressure greater than 200 mm of H2O, and normal CSF composition. No common medication, condition, or disease except cystinosis was found in these persons. Six of the patients had received prednisone, growth hormone, cyclosporine, oral contraceptives, vitamin D, or levothyroxine at the time of onset of IIH. Five patients had previous renal transplants. CONCLUSION No single risk factor for the development of IIH linked IIH to cystinosis in our patients. However, thrombosis susceptibility as a result of renal disease or impaired CSF reabsorption in the arachnoid villi as a result of cystine deposition might lead to the development of IIH in cystinosis.
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Affiliation(s)
- Cigdem F Dogulu
- Laboratory of Clinical Genomics, National Institute of Child Health and Development, Opthalmic Clinical Genetics Section, National Institutes of Health, Bethesda, MD 20892-4429, USA.
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Abstract
We report the excellent clinical outcomes of siblings with nephropathic cystinosis treated diligently with cysteamine starting at 20 months and 2 months of age. Now 15 and 8 years old, they have glomerular filtration rates of 78 and 105 mL/min/1.73m 2 , respectively. These cases illustrate the critical importance of early diagnosis and treatment.
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Abstract
Cystinosis is an autosomal recessive disease that results in a defective integral membrane protein responsible for the transport of cystine out of lysosomes. This results in the accumulation of cystine in the lysosomes of almost every tissue, with subsequent formation of damaging crystals. The cystinotic process may affect every system of the body, but is particularly damaging to the kidneys and eyes. We discuss the perioperative care of a cystinotic patient with renal insufficiency, Fanconi's syndrome, and photophobia. Other organ systems affected by the cystinotic process are also discussed, with suggestions for the perioperative management of each. Issues of primary concern during perioperative care include preservation of renal function and maintenance of fluid and electrolyte homeostasis.
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Affiliation(s)
- Theresa L Ray
- Department of Child Health, The Division of Pediatric Critical Care/Pediatric Anesthesiology, The University of Missouri, Columbia, MO, USA
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Abstract
UNLABELLED Nephropathic cystinosis is an autosomal recessive lysosomal storage disorder in which intracellular cystine accumulates due to impaired transport out of lysosomes. The clinical manifestations include renal tubular Fanconi syndrome in the 1st year of life, with hypophosphatemic rickets, hypokalemia, polyuria, dehydration and acidosis, growth retardation, hypothyroidism, photophobia, renal glomerular deterioration by 10 years of age, and late complications such as myopathy, pancreatic insufficiency, and retinal blindnesss. The cystinosis gene, CTNS, codes for cystinosin, a 367 amino acid protein with seven transmembrane domains. More than 50 CTNSmutations have been identified, but approximately 50% of Northern European patients have a 57257-bp deletion which removes the first nine exons of CTNS. The mainstay of cystinosis therapy is oral cysteamine (Cystagon). This aminothiol can lower intracellular cystine content by 95%, and has proven efficacy in delaying renal glomerular deterioration, enhancing growth, preventing hypothyroidism, and lowering muscle cystine content. Its early and diligent use is critical; in one study, for every month of treatment prior to 3 years of age, 14 months' worth of later renal function were preserved. Several examples of individual patients treated early and having preserved renal function and normal growth are available. Newborn screening using a chip containing cDNA to detect common CTNSmutations may allow diagnosis and treatment in the first weeks of life. CONCLUSIONS Early diagnosis and treatment of nephropathic cystinosis can change the course of this disease.
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Affiliation(s)
- William A Gahl
- Section on Human Biochemical Genetics, National Institute of Child Health and Human Development, National Institutes of Health, MSC 1851 Building 10, Room 10C-103, 10 Center Drive, Bethesda, Maryland 20892-1851, USA.
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Affiliation(s)
- William A Gahl
- Heritable Disorders Branch, National Institute of Child Health and Human Development, Bethesda, Md 20892-1830, USA.
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Kleta R, Anikster Y, Lucero C, Shotelersuk V, Huizing M, Bernardini I, Park M, Thoene J, Schneider J, Gahl WA. CTNS mutations in African American patients with cystinosis. Mol Genet Metab 2001; 74:332-7. [PMID: 11708862 DOI: 10.1006/mgme.2001.3218] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cystinosis, an autosomal recessive lysosomal storage disorder, is rarely diagnosed in African Americans. The disease results from mutations in the gene CTNS; at least 55 such mutations have been reported. By far the most common is a 57,257-bp deletion of Northern European origin encompassing most of the CTNS gene. We performed mutation analysis on DNA from four African American patients with cystinosis. In one individual with classical, nephropathic cystinosis, we identified a new molecular defect, i.e., a homozygous GT-->CC substitution at the +5 position of IVS 5 of CTNS (IVS 5+5 GT-->CC). The out-of-frame splicing of exon 5 creates a null allele consistent with the patient's severe phenotype. Two patients were heterozygous and one homozygous for the common 57-kb deletion allele, reflecting the admixture of African and Northern European gene pools in North America. The two African Americans heterozygous for the 57-kb deletion were also hemizygous for a 928G-->A change, associated with ocular or nonnephropathic cystinosis. These two individuals are the only known African Americans with ocular cystinosis. We conclude that the diagnosis of cystinosis should be entertained in African Americans with symptoms of the disease, and that mutation analysis for the 57-kb deletion should be considered in this group of patients.
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Affiliation(s)
- R Kleta
- Section on Human Biochemical Genetics, Heritable Disorders Branch, National Institute of Child Health and Human Development/NIH, 10 Center Drive, Building 10, Bethesda, MD 20892, USA
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