1
|
Santa Paola S, Di Blasi FD, Borgione E, Lo Giudice M, Giuliano M, Pettinato R, Di Stefano V, Brighina F, Lupica A, Scuderi C. Aromatic L-Amino Acid Decarboxylase Deficiency: A Genetic Screening in Sicilian Patients with Neurological Disorders. Genes (Basel) 2024; 15:134. [PMID: 38275615 PMCID: PMC10815063 DOI: 10.3390/genes15010134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/09/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024] Open
Abstract
Aromatic L-amino acid decarboxylase deficiency (AADCd) is a rare autosomal recessive neurometabolic disorder caused by AADC deficiency, an enzyme encoded by the DDC gene. Since the enzyme is involved in the biosynthesis of serotonin and dopamine, its deficiency determines the lack of these neurotransmitters, but also of norepinephrine and epinephrine. Onset is early and the key signs are hypotonia, movement disorders (oculogyric crises, dystonia and hypokinesia), developmental delay and autonomic dysfunction. Taiwan is the site of a potential founder variant (IVS6+4A>T) with a predicted incidence of 1/32,000 births, while only 261 patients with this deficit have been described worldwide. Actually, the number of affected persons could be greater, given that the spectrum of clinical manifestations is broad and still little known. In our study we selected 350 unrelated patients presenting with different neurological disorders including heterogeneous neuromuscular disorders, cognitive deficit, behavioral disorders and autism spectrum disorder, for which the underlying etiology had not yet been identified. Molecular investigation of the DDC gene was carried out with the aim of identifying affected patients and/or carriers. Our study shows a high frequency of carriers (2.57%) in Sicilian subjects with neurological deficits, with a higher concentration in northern and eastern Sicily. Assuming these data as representative of the general Sicilian population, the risk may be comparable to some rare diseases included in the newborn screening programs such as spinal muscular atrophy, cystic fibrosis and phenylketonuria.
Collapse
Affiliation(s)
- Sandro Santa Paola
- Unit of Neuromuscular Diseases, Oasi Research Institute-IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy; (E.B.); (M.L.G.); (M.G.); (C.S.)
| | | | - Eugenia Borgione
- Unit of Neuromuscular Diseases, Oasi Research Institute-IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy; (E.B.); (M.L.G.); (M.G.); (C.S.)
| | - Mariangela Lo Giudice
- Unit of Neuromuscular Diseases, Oasi Research Institute-IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy; (E.B.); (M.L.G.); (M.G.); (C.S.)
| | - Marika Giuliano
- Unit of Neuromuscular Diseases, Oasi Research Institute-IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy; (E.B.); (M.L.G.); (M.G.); (C.S.)
| | - Rosa Pettinato
- Unit of Pediatrics and Medical Genetics, Oasi Research Institute-IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy;
| | - Vincenzo Di Stefano
- Department of Biomedicine, Neuroscience and Advanced Diagnostic (BIND), University of Palermo, Via del Vespro, 143, 90127 Palermo, Italy; (V.D.S.); (F.B.); (A.L.)
| | - Filippo Brighina
- Department of Biomedicine, Neuroscience and Advanced Diagnostic (BIND), University of Palermo, Via del Vespro, 143, 90127 Palermo, Italy; (V.D.S.); (F.B.); (A.L.)
| | - Antonino Lupica
- Department of Biomedicine, Neuroscience and Advanced Diagnostic (BIND), University of Palermo, Via del Vespro, 143, 90127 Palermo, Italy; (V.D.S.); (F.B.); (A.L.)
| | - Carmela Scuderi
- Unit of Neuromuscular Diseases, Oasi Research Institute-IRCCS, Via Conte Ruggero 73, 94018 Troina, Italy; (E.B.); (M.L.G.); (M.G.); (C.S.)
| |
Collapse
|
2
|
Riva A, Iacomino M, Piccardo C, Franceschetti L, Franchini R, Baroni A, Minetti C, Bisello G, Zara F, Scala M, Striano P, Bertoldi M. Exome sequencing data screening to identify undiagnosed Aromatic l-amino acid decarboxylase deficiency in neurodevelopmental disorders. Biochem Biophys Res Commun 2023; 673:131-136. [PMID: 37385007 DOI: 10.1016/j.bbrc.2023.06.065] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 06/19/2023] [Indexed: 07/01/2023]
Abstract
Aromatic l-amino acid decarboxylase (AADC) deficiency is a rare autosomal recessive neurometabolic disorder caused by biallelic pathogenic variants in the DDC gene and mainly characterized by developmental delay, hypotonia, and oculogyric crises. Early diagnosis is crucial for correct patient management; however, many patients remain misdiagnosed or undiagnosed due to the rarity and clinical heterogeneity of the disorder especially in the milder forms. Here, we applied exome sequencing approach by screening 2000 paediatric patients with neurodevelopmental disorders to identify possible new AADC variants and AADC deficiency patients. We identified five distinct DDC variants in two unrelated individuals. Patient #1 harboured two compound heterozygous DDC variants: c.436-12T > C and c.435 + 24A>C and presented with psychomotor delay, tonic spasms, and hyperreactivity. Patient #2 had three homozygous AADC variants: c.1385G > A; p.Arg462Gln, c.234C > T; p.Ala78 = , and c.201 + 37A > G and presented with developmental delay and myoclonic seizures. The variants were classified as benign class I variants and therefore non-causative according to the ACMG/AMP guidelines. Since the AADC protein is a structural and functional obligate homodimer, we evaluated the possible AADC polypeptide chain combinations in the two patients and determined the effects resulting from the amino acid substitution Arg462Gln. Our patients carrying DDC variants presented clinical manifestations not precisely overlapped to the classical symptoms exhibited by the most severe AADC deficiency cases. However, screening data derived from exome sequencing in patients featuring wide-range symptoms related to neurodevelopmental disorders may help to identify AADC deficiency patients, especially when applied to larger cohorts.
Collapse
Affiliation(s)
- Antonella Riva
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Michele Iacomino
- Unit of Medical Genetics, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Chiara Piccardo
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | | | - Rossella Franchini
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | | | - Carlo Minetti
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Giovanni Bisello
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Federico Zara
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Unit of Medical Genetics, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Marcello Scala
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy; Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Mariarita Bertoldi
- Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.
| |
Collapse
|
3
|
Analysis of urinary organic acids by gas chromatography tandem mass spectrometry method for metabolic profiling applications. J Chromatogr A 2021; 1658:462590. [PMID: 34666271 DOI: 10.1016/j.chroma.2021.462590] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/14/2021] [Accepted: 09/27/2021] [Indexed: 12/12/2022]
Abstract
A sensitive, accurate and precise method was developed for the quantification of a large number of organic acids in human urine by GC-MS/MS. The analytes were selected based on their role as key metabolic intermediates; intermediates of Krebs cycle, fatty acid oxidation, glycolysis, down-stream metabolites of neurotransmitter synthesis and degradation, metabolites indicative of nutritional deficiencies, byproducts of microbial activity in the gastrointestinal tract (GI) etc. The most efficient sample preparation protocol was selected based on tests for extraction with different solvents such as MTBE and ethyl acetate under acidic conditions, whereas finally a more general protocol was applied with methanol. Regarding derivatization, methoxyamine with MSTFA, 1% TMCS was applied. The method was extensively validated, including stability study, ensuring accurate determination of the studied organic acids in human urine. Proof of its utility was exhibited in a set of samples from human volunteers. The method can find wide applicability in the context of metabolomics for clinical or nutritional studies.
Collapse
|
4
|
Opladen T, Brennenstuhl H, Kuseyri Hübschmann O, Call D, Green K, Schara U, Rascher W, Hövel A, Assmann B, Kölker S, Westhoff JH, Walter M, Ziegler A, Hoffmann GF, Kiening K. Die intrazerebrale Gentherapie des Aromatischen-L-Aminosäure-Decarboxylase-Mangels mit Eladocagene exuparvovec. Monatsschr Kinderheilkd 2021. [DOI: 10.1007/s00112-021-01232-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
5
|
Ling TK, Wong KC, Chan CY, Lau NKC, Law CY, Lee HCH, Lai CK, Chong YK, Yau KCE, Cheung KM, Ko CH, Fung CW, Lee LK, Wong SSN, Mak CM, Chan AYW, Tam S, Lam CW. Urine organic acid as the first clue towards aromatic L-amino acid decarboxylase (AADC) deficiency in a high prevalence area. Clin Chim Acta 2021; 521:40-44. [PMID: 34161777 DOI: 10.1016/j.cca.2021.06.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 06/17/2021] [Accepted: 06/18/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND Aromatic L-amino acid decarboxylase deficiency is a rare neurometabolic disease due to impaired decarboxylation of neurotransmitter precursors to its active form. CASE We retrospectively reviewed 8 cases from 2008 to 2019 with cerebrospinal fluid neurotransmitter analysis performed at our centre. All cases had an elevated urine vanillactic acid and, in most cases, with N-acetylvanilalanine detected. Cerebrospinal fluid analysis showed low downstream metabolites vanillylmandelic acid, homovanillic acid but high 3-O-methyl-L-DOPA, 5-hydroxytryptophan. Cerebrospinal fluid pterins were normal. Genotyping in DDC confirms the diagnosis. Urine organic acid analysis provided the first clue to diagnosis in four of the cases, which then triggered cerebrospinal fluid neurotransmitter and genetic analysis. We also developed a diagnostic decision support system to assist the interpretation of the mass spectrometry data from urine organic acids. CONCLUSIONS Urine organic acid could be essential in guiding subsequent investigations for the diagnosis of aromatic L-amino acid decarboxylase deficiency. We propose to screen suspected cases first with urine organic acids, specifically looking for vanillactic acid and N-acetylvanilalanine. Suggestive findings should be followed with target analysis for c.714 + 4A > T in ethnically Chinese patients. The assistive tool allowed expedite interpretation of profile data generated from urine organic acids analysis. It may also reduce interpreter's bias when peaks of interest are minor peaks in the spectrum.
Collapse
Affiliation(s)
- Tsz-Ki Ling
- Department of Pathology, Queen Mary Hospital, Hong Kong, China
| | - Ka-Chung Wong
- Department of Pathology, Queen Mary Hospital, Hong Kong, China
| | - Candace Yim Chan
- Department of Pathology, Princess Margaret Hospital, Hong Kong, China
| | | | - Chun-Yiu Law
- Department of Pathology, Queen Mary Hospital, Hong Kong, China
| | | | - Chi-Kong Lai
- Department of Pathology, Princess Margaret Hospital, Hong Kong, China
| | - Yeow-Kuan Chong
- Department of Pathology, Princess Margaret Hospital, Hong Kong, China
| | - Kin-Cheong Eric Yau
- Department of Paediatrics and Adolescent Medicine, Princess Margaret Hospital, Hong Kong, China
| | - Ka-Ming Cheung
- Department of Paediatrics and Adolescent Medicine, Caritas Medical Centre, Hong Kong, China
| | - Chun-Hung Ko
- Department of Paediatrics and Adolescent Medicine, Caritas Medical Centre, Hong Kong, China
| | - Cheuk-Wing Fung
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, Hong Kong, China
| | - Lai-Ka Lee
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, Hong Kong, China
| | - Sheila Suet-Na Wong
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, Hong Kong, China
| | - Chloe M Mak
- Department of Pathology, Hong Kong Children's Hospital, Hong Kong, China
| | - Albert Yan-Wo Chan
- Department of Pathology, Hong Kong Children's Hospital, Hong Kong, China
| | - Sidney Tam
- Department of Pathology, Queen Mary Hospital, Hong Kong, China
| | - Ching-Wan Lam
- Department of Pathology, Queen Mary Hospital, Hong Kong, China; Department of Pathology, The University of Hong Kong, Hong Kong, China.
| |
Collapse
|
6
|
Burlina A, Giuliani A, Polo G, Gueraldi D, Gragnaniello V, Cazzorla C, Opladen T, Hoffmann G, Blau N, Burlina AP. Detection of 3-O-methyldopa in dried blood spots for neonatal diagnosis of aromatic L-amino-acid decarboxylase deficiency: The northeastern Italian experience. Mol Genet Metab 2021; 133:56-62. [PMID: 33744095 DOI: 10.1016/j.ymgme.2021.03.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Aromatic L-amino acid decarboxylase (AADC) deficiency is a rare inherited autosomal recessive disorder of biogenic amine metabolism. Diagnosis requires analysis of neurotransmitter metabolites in cerebrospinal fluid, AADC enzyme activity analysis, or molecular analysis of the DDC gene. 3-O-methyldopa (3-OMD) is a key screening biomarker for AADC deficiency. METHODS We describe a rapid method for 3-OMD determination in dried blood spots (DBS) using flow-injection analysis tandem mass spectrometry with NeoBase™ 2 reagents and 13C6-tyrosine as an internal standard, which are routinely used in high-throughput newborn screening. We assessed variability using quality control samples over a range of 3-OMD concentrations. RESULTS Within-day and between-day precision determined with quality control samples demonstrated coefficients of variation <15%. 3-OMD concentrations in 1000 healthy newborns revealed a mean of 1.33 μmol/L (SD ± 0.56, range 0.61-3.05 μmol/L), 100 non-AADC control subjects (age 7 days - 1 year) showed a mean of 1.19 μmol/L (SD ± 0.35-2.00 μmol/L), and 81 patients receiving oral L-Dopa had a mean 3-OMD concentration of 14.90 μmol/L (SD ± 14.18, range 0.4-80.3 μmol/L). A patient with confirmed AADC was retrospectively analyzed and correctly identified (3-OMD 10.51 μmol/L). In April 2020, we started a pilot project for identifying AADC deficiency in DBSs routinely submitted to the expanded newborn screening program. 3-OMD concentrations were measured in 21,867 samples; no patients with AADC deficiency were identified. One newborn had a high 3-OMD concentration due to maternal L-Dopa treatment. DISCUSSION We demonstrated a rapid new method to identify AADC deficiency using reagents and equipment already widely used in newborn screening programs. Although our study is limited, introduction of our method in expanded neonatal screening is feasible and could facilitate deployment of screening, allowing for early diagnosis that is important for effective treatment.
Collapse
Affiliation(s)
- Alberto Burlina
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy.
| | - Antonella Giuliani
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Giulia Polo
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Daniela Gueraldi
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Vincenza Gragnaniello
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Chiara Cazzorla
- Division of Inherited Metabolic Diseases, Department of Diagnostic Services, University Hospital, Padua, Italy
| | - Thomas Opladen
- Department of Pediatrics, University of Heidelberg, Germany
| | - Georg Hoffmann
- Department of Pediatrics, University of Heidelberg, Germany
| | - Nenad Blau
- Division of Metabolism, University Children's Hospital, Zürich, Switzerland
| | | |
Collapse
|
7
|
Wassenberg T, Geurtz BPH, Monnens L, Wevers RA, Willemsen MA, Verbeek MM. Blood, urine and cerebrospinal fluid analysis in TH and AADC deficiency and the effect of treatment. Mol Genet Metab Rep 2021; 27:100762. [PMID: 33996491 PMCID: PMC8093927 DOI: 10.1016/j.ymgmr.2021.100762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 04/19/2021] [Indexed: 12/03/2022] Open
Abstract
Background Aromatic L-amino acid decarboxylase (AADC) deficiency and tyrosine hydroxylase (TH) deficiency are rare inherited disorders of monoamine neurotransmitter synthesis which are typically diagnosed using cerebrospinal fluid examination of monoamine neurotransmitter metabolites. Until now, it has not been systematically studied whether analysis of monamine neurotransmitter metabolites in blood or urine has diagnostic value as compared to cerebrospinal fluid examination, or whether monoamine neurotransmitter metabolites in these peripheral body fluids is useful to monitor treatment efficacy. Methods Assessment, both by literature review and retrospective analysis of our local university hospital database, of monoamine neurotransmitter metabolites in urine, blood and cerebrospinal fluid, and serum prolactin levels, before and during treatment in patients with AADC and TH deficiency. Results In AADC deficiency, 3-O-methyldopa in serum or dried blood spots was reported in 34 patients and found to be (strongly) increased in all, serotonin in serum was decreased in 7/7 patients. Serum prolactin was increased in 34/37 and normal in 3 untreated patients. In urine, dopamine was normal or increased in 21/24 patients, 5-hydroxyindoleacetic acid was decreased in 9/10 patients, and vanillactic acid was increased in 19/20 patients. No significant changes were seen in monoamine neurotransmitter metabolites after medical treatment, except for an increase of homovanillic acid in urine and cerebrospinal fluid after levodopa therapy, sometimes even in absence of a clinical response. After gene therapy, cerebrospinal fluid homovanillic acid increased in most patients (8/12), but 5-hydroxyindoleacetic acid remained unchanged in 9/12 patients. In TH deficiency, serum prolactin was increased in 12/14 and normal in the remaining untreated patients. Urinary dopamine was decreased in 2/8 patients and normal in 6. Homovanillic acid concentrations in cerebrospinal fluid increased upon levodopa treatment, even in the absence of a clear treatment response. Conclusions This study confirms that cerebrospinal fluid is the most informative body fluid to measure monoamine neurotransmitter metabolites when AADC or TH deficiency is suspected, and that routine follow-up of cerebrospinal fluid measurements to estimate treatment response is not needed. 3-O-methyldopa in dried blood spots and vanillactic acid in urine are promising peripheral biomarkers for diagnosis of AADC deficiency. However, in many patients with TH or AADC deficiency dopamine in urine is normal or increased thereby not reflecting the metabolic block. The value of serum prolactin for follow-up of AADC and TH deficiency should be further studied.
Collapse
Key Words
- 3-OMD, 3-O-methyldopa
- 5-HIAA, 5-Hydroxyindoleacetic acid
- 5-HTP, 5-Hydroxytryptophan
- AADC deficiency
- AADC, Aromatic L-amino acid decarboxylase
- Aromatic L-amino acid decarboxylase deficiency
- Biomarkers
- CSF, Cerebrospinal fluid
- HVA, Homovanillic acid
- MHPG, 3-methoxy 4-hydroxyphenylglycol
- Monoamine neurotransmitter deficiency
- TH deficiency
- TH, Tyrosine hydroxylase
- TML, Translational Metabolic Laboratory
- Tyrosine hydroxylase deficiency
- VLA, Vanillactic acid
- VMA, Vanillylmandelic acid
Collapse
Affiliation(s)
- Tessa Wassenberg
- Radboud university medical center, Department of Neurology (943), Donders Institute for Brain, Cognition and Behaviour, PO Box 9101, 6500 HB, Nijmegen, the Netherlands.,Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZ Brussel), Department of Pediatrics, Pediatric Neurology Unit, Laarbeeklaan 101, 1090 Brussels, Belgium
| | - Ben P H Geurtz
- Radboud university medical center, Department of Laboratory Medicine, Translational Metabolic Laboratory (830), PO Box 9101, 6500 HB, Nijmegen, the Netherlands
| | - Leo Monnens
- Radboud university medical center, Department of Physiology (392), PO Box 9101, 6500 HB, Nijmegen, the Netherlands
| | - Ron A Wevers
- Radboud university medical center, Department of Laboratory Medicine, Translational Metabolic Laboratory (830), PO Box 9101, 6500 HB, Nijmegen, the Netherlands
| | - Michèl A Willemsen
- Radboud university medical center, Amalia Children's Hospital, Department of Pediatric Neurology (801), Donders Institute for Brain, Cognition and Behaviour, PO Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Marcel M Verbeek
- Radboud university medical center, Department of Neurology (943), Donders Institute for Brain, Cognition and Behaviour, PO Box 9101, 6500 HB, Nijmegen, the Netherlands.,Radboud university medical center, Department of Laboratory Medicine, Translational Metabolic Laboratory (830), PO Box 9101, 6500 HB, Nijmegen, the Netherlands
| |
Collapse
|
8
|
Illsinger S, Korenke GC, Boesch S, Nocker M, Karall D, Nuoffer JM, Laugwitz L, Mayr JA, Scholl-Bürgi S, Freisinger P, Kowald T, Kölker S, Prokisch H, Haack TB. Paroxysmal and non-paroxysmal dystonia in 3 patients with biallelic ECHS1 variants: Expanding the neurological spectrum and therapeutic approaches. Eur J Med Genet 2020; 63:104046. [PMID: 32858208 DOI: 10.1016/j.ejmg.2020.104046] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/16/2020] [Accepted: 08/20/2020] [Indexed: 12/25/2022]
Abstract
BACKGROUND ECHS1 encodes the mitochondrial short chain enoyl CoA hydratase 1 (SCEH). Biallelic ECHS1 variants have been associated with Leigh-like presentations and milder phenotypes with paroxysmal exercise-induced dystonia. PATIENTS/METHODS We used exome sequencing to investigate molecular bases of paroxysmal and non-paroxysmal dystonia in three patients and performed functional studies in fibroblasts. Disease presentation and response upon dietary interventions were documented. RESULTS We identified compound heterozygous ECHS1 missense variants in all individuals; all of them harbouring an c.518C > T (p.Ala173Val) variant. SCEH activity was impaired in patients' fibroblasts, respiratory chain-, and pyruvate-dehydrogenase-complex activities were normal in one individual. Patient 1 presented from the age of 2.5 years on with paroxysmal opisthotonic posturing. Patient 2 had a first metabolic crisis at the age 20 months developing recurrent exercise-induced dystonic episodes. Disease history of patient 3 was unremarkable for neurological findings until he first presented at the age of 20 years with persistent dystonia. Ketogenic diet had beneficial effects in patient 1. Neither ketogenic nor low protein diets led to milder symptoms in patient 2. Patient 3 benefits from low protein diet with improvement of his torticollis. CONCLUSIONS In line with literature, our findings corroborate that the pathogenic ECHS1 variant c.518C > T (p.Ala173Val) is associated with milder phenotypes characterized by paroxysmal and non-paroxysmal dystonia. Because of the potentially treatable defect, especially in milder affected patients, it is important to consider SCEH deficiency not only in patients with Leigh-like syndrome but also in patients with paroxysmal dystonia and normal neurological findings between episodes.
Collapse
Affiliation(s)
- Sabine Illsinger
- University Children's Hospital Oldenburg, Department of Neuropaediatric and Metabolic Diseases, Oldenburg, Germany.
| | - G Christoph Korenke
- University Children's Hospital Oldenburg, Department of Neuropaediatric and Metabolic Diseases, Oldenburg, Germany
| | - Sylvia Boesch
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Michael Nocker
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Daniela Karall
- Department of Paediatrics I, Inherited Metabolic Disorders, Medical University of Innsbruck, Innsbruck, Austria
| | - Jean M Nuoffer
- University Institute of Clinical Chemistry, Bern University Hospital, Bern, Switzerland; Pediatric Endocrinology, Diabetology and Metabolism, University Children's Hospital Bern, Switzerland
| | - Lucia Laugwitz
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany; Department of Neuropediatrics, Developmental Neurology and Social Pediatrics, University of Tübingen, 72076, Tübingen, Germany
| | - Johannes A Mayr
- Department of Pediatrics, University Hospital Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Sabine Scholl-Bürgi
- Department of Paediatrics I, Inherited Metabolic Disorders, Medical University of Innsbruck, Innsbruck, Austria
| | - Peter Freisinger
- Department of Pediatrics, Klinikum Reutlingen, Reutlingen, Germany
| | - Tobias Kowald
- Institute for Diagnostic and Interventional Radiology, Klinikum Oldenburg, Oldenburg, Germany
| | - Stefan Kölker
- Division of Child Neurology and Metabolic Medicine, Centre for Child and Adolescent Medicine, University Hospital Heidelberg, Germany
| | - Holger Prokisch
- Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany; Institute of Human Genetics, Technische Universität München, Munich, Germany
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany; Institute of Human Genetics, Technische Universität München, Munich, Germany; Centre for Rare Diseases, University of Tuebingen, Tübingen, Germany
| |
Collapse
|