Diagnosis, treatment, and management of rickets: a position statement from the Bone and Mineral Metabolism Group of the Italian Society of Pediatric Endocrinology and Diabetology

Rickets results from impaired mineralization of growing bone due to alterations in calcium and phosphate homeostasis. Clinical signs of rickets are related to the age of the patient, the duration of the disease, and the underlying disorder. The most common signs of rickets are swelling of the wrists, knees or ankles, bowing of the legs (knock-knees, outward bowing, or both) and inability to walk. However, clinical features alone cannot differentiate between the various forms of rickets. Rickets includes a heterogeneous group of acquired and inherited diseases. Nutritional rickets is due to a deficiency of vitamin D, dietary calcium or phosphate. Mutations in genes responsible for vitamin D metabolism or function, the production or breakdown of fibroblast growth factor 23, renal phosphate regulation, or bone mineralization can lead to the hereditary form of rickets. This position paper reviews the relevant literature and presents the expertise of the Bone and Mineral Metabolism Group of the Italian Society of Pediatric Endocrinology and Diabetology (SIEDP). The aim of this document is to provide practical guidance to specialists and healthcare professionals on the main criteria for diagnosis, treatment, and management of patients with rickets. The various forms of rickets are discussed, and detailed references for the discussion of each form are provided. Algorithms to guide the diagnostic approach and recommendations to manage patients with rare forms of hereditary rickets are proposed.

Hormonal control during infancy and testicular adrenal rest tumor development in males with congenital adrenal hyperplasia: a retrospective multicenter cohort study

IMPORTANCE

Testicular adrenal rest tumors (TARTs), often found in male patients with congenital adrenal hyperplasia (CAH), are benign lesions causing testicular damage and infertility. We hypothesize that chronically elevated adrenocorticotropic hormone exposure during early life may promote TART development.

OBJECTIVE

This study aimed to examine the association between commencing adequate glucocorticoid treatment early after birth and TART development.

DESIGN AND PARTICIPANTS

This retrospective multicenter (n = 22) open cohort study collected longitudinal clinical and biochemical data of the first 4 years of life using the I-CAH registry and included 188 male patients (median age 13 years; interquartile range: 10-17) with 21-hydroxylase deficiency (n = 181) or 11-hydroxylase deficiency (n = 7). All patients underwent at least 1 testicular ultrasound.

RESULTS

TART was detected in 72 (38%) of the patients. Prevalence varied between centers. When adjusted for CAH phenotype, a delayed CAH diagnosis of >1 year, compared with a diagnosis within 1 month of life, was associated with a 2.6 times higher risk of TART diagnosis. TART onset was not predicted by biochemical disease control or bone age advancement in the first 4 years of life, but increased height standard deviation scores at the end of the 4-year study period were associated with a 27% higher risk of TART diagnosis.

CONCLUSIONS AND RELEVANCE

A delayed CAH diagnosis of >1 year vs CAH diagnosis within 1 month after birth was associated with a higher risk of TART development, which may be attributed to poor disease control in early life.

Predictors of surgical complications in boys with hypospadias: data from an internationa registry

Background

Complications are frequently reported after hypospadias repair and there is a need to understand the factors that influence their occurrence.

Methods

Data from boys with hypospadias born between 2000 and 2020 were obtained from the International Disorders of Sex Development (I-DSD) Registry. Logistic regressions, fisher's exact tests and spearman's correlation tests were performed on the data to assess associations between clinical factors and complication rates.

Results

Of the 551 eligible boys, data were available on 160 (29%). Within the cohort, the median (range) External Masculinization Score (EMS) was 6 (2, 9). All presented with one or more additional genital malformation and 61 (38%) presented with additional extragenital malformations. Disorders of androgen action, androgen synthesis and gonadal development were diagnosed in 28 (18%), 22 (14%) and 9 (6%) boys, respectively. The remaining 101 (62%) patients were diagnosed as having non-specific 46,XY Disorders of Sex Development. Eighty (50%) boys had evidence of abnormal biochemistry, and gene variants were identified in 42 (26%). Median age at first hypospadias surgery was 2 years (0, 9), and median length of follow-up was 5 years (0, 17). Postsurgical complications were noted in 102 (64%) boys. There were no significant associations with postsurgical complications.

Conclusions

Boys with proximal hypospadias in the I-DSD Registry have high rates of additional comorbidities and a high risk of postoperative complications. No clinical factors were significantly associated with complication rates. High complication rates with no observable cause suggest the involvement of other factors which need investigation.

A Case of Acrodermatitis Dysmetabolica in a Child Affected by Citrullinemia Type I: When Early Diagnosis and Timely Treatment Are Not Enough

An infant with a prenatal diagnosis of citrullinemia, who started standard treatment at birth (L-arginine; sodium benzoate and a personalized diet characterized by a low protein intake and supplementation of essential nutrients and amino acids), presented at 4 months of age with extended, progressive, and severe skin lesions consistent with acrodermatitis dysmetabolica. Guidelines for the diagnosis and management of urea cycle disorders underline that a low-protein diet places patients at risk of essential fatty acids, trace elements, and vitamin deficiency. At hospital admission, our patient had normal levels of zinc and alkaline phosphatases. The plasmatic amino acid profile revealed a severe and generalized deficiency. In particular, the serum levels of arginine, valine, and isoleucine were very low and the dermatitis did not improve until the blood levels of these amino acids increased. In our patient, skin lesions happened despite an early diagnosis of citrullinemia and timely treatment due to compliance issues as a consequence of linguistic barriers.

Testicular Adrenal Rest Tumors in Congenital Adrenal Hyperplasia: Study of a Cohort of Patients from a Single Italian Center

Testicular adrenal rest tumors (TARTs) are a common complication in male patients with congenital adrenal hyperplasia (CAH). The aim of our cross-sectional cohort study is to estimate the frequency of TARTs with the correlation of genotype and disease control on tumor development. Thirty-five male patients, aged 14-26 years, were included in the study, all followed by the same center of pediatric endocrinology in Bologna. We studied genotypes, hormonal profiles at different time intervals and testicular ultrasound. A logistic regression model with multivariant analysis was developed for the statistical analysis. TARTs were detected in 31.4% of the cases, 90.9% of them had a classic form with salt wasting, while 9.1% had a non-classic form. Additionally, a significant correlation between the incidence of TARTs and severity of genotype was detected. Patients with TARTs had markedly worse metabolic control on average (p = 0.027), reflected by high ACTH, 17OH progesterone, and overall delta4-androstenedione. In conclusion, a screening tool is mandatory, especially (but not exclusively) in patients with the most severe forms of CAH and poor endocrine control of the disease.

Reduced serum concentrations of biomarkers reflecting Leydig and Sertoli cell function in male patients with congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is a recessive condition that affects the adrenal glands. Despite life-long replacement therapy with glucocorticoids and mineralocorticoids, adult patients with CAH often experience impaired gonadal function. In pubertal boys and in men with CAH, circulating testosterone is produced by the adrenal glands as well as the testicular, steroidogenic cells. In this European two-center study, we evaluated the function of Leydig and Sertoli cells in 61 boys and men with CAH, primarily due to 21-hydroxylase deficiency. Despite conventional hormone replacement therapy, our results indicated a significant reduction in serum concentrations of both Leydig cell-derived hormones (i.e. insulin-like factor 3 (INSL3) and testosterone) and Sertoli cell-derived hormones (i.e. inhibin B and anti-Müllerian hormone) in adult males with CAH. Serum concentrations of INSL3 were particularly reduced in those with testicular adrenal rest tumors. To our knowledge, this is the first study to evaluate circulating INSL3 as a candidate biomarker to monitor Leydig cell function in patients with CAH.

Outcome of COVID-19 infections in patients with adrenal insufficiency and excess

BACKGROUND

Information on clinical outcomes of coronavirus disease 19 (COVID-19) infection in patients with adrenal disorders is scarce.

METHODS

A collaboration between the European Society of Endocrinology (ESE) Rare Disease Committee and European Reference Network on Rare Endocrine Conditions via the European Registries for Rare Endocrine Conditions allowed the collection of data on 64 cases (57 adrenal insufficiency (AI), 7 Cushing's syndrome) that had been reported by 12 centres in 8 European countries between January 2020 and December 2021.

RESULTS

Of all 64 patients, 23 were males and 41 females (13 of those children) with a median age of 37 and 51 years. In 45/57 (95%) AI cases, COVID-19 infection was confirmed by testing. Primary insufficiency was present in 45/57 patients; 19 were affected by Addison's disease, 19 by congenital adrenal hyperplasia and 7 by primary AI (PAI) due to other causes. The most relevant comorbidities were hypertension (12%), obesity (n = 14%) and diabetes mellitus (9%). An increase by a median of 2.0 (IQR 1.4) times the daily replacement dose was reported in 42 (74%) patients. Two patients were administered i.m. injection of 100 mg hydrocortisone, and 11/64 were admitted to the hospital. Two patients had to be transferred to the intensive care unit, one with a fatal outcome. Four patients reported persistent SARS-CoV-2 infection, all others complete remission.

CONCLUSION

This European multicentre questionnaire is the first to collect data on the outcome of COVID-19 infection in patients with adrenal gland disorders. It suggests good clinical outcomes in case of duly dose adjustments and emphasizes the importance of patient education on sick day rules.

Long-term cardiometabolic morbidity in young adults with classic 21-hydroxylase deficiency congenital adrenal hyperplasia

PURPOSE

To study the current practice for assessing comorbidity in adults with 21-hydroxylase CAH and to assess the prevalence of comorbidity in these adults.

METHODS

A structured questionnaire was sent to 46 expert centres managing adults with CAH. Information collected included current therapy and surveillance practice with a particular focus on osteoporosis/osteopaenia, hyperlipidaemia, type 2 diabetes/hyperinsulinaemia, hypertension, CV disease, obesity.

RESULTS

Of the 31 (67%) centres from 15 countries that completed the survey, 30 (97%) screened for hypertension by measuring blood pressure, 30 (97%) screened for obesity, 26 (84%) screened for abnormal glucose homoeostasis mainly by using Hb1Ac (73%), 25 (81%) screened for osteoporosis mainly by DXA (92%), 20 (65%) screened for hyperlipidaemia and 6 (19%) screened for additional CV disease. Of the 31 centres, 13 provided further information on the six co-morbidities in 244 patients with a median age of 33 yrs (range 19, 94). Of these, 126 (52%) were females and 174 (71%) received fludrocortisone in addition to glucocorticoids. Of the 244 adults, 73 (30%) were treated for at least one comorbidity and 15 (21%) for more than 2 co-morbidities. Of 73, the patients who were treated for osteoporosis/osteopaenia, hyperlipidaemia, type 2 diabetes/hyperinsulinaemia, hypertension, CV disease, obesity were 43 (59%), 17 (23%), 16 (22%), 10 (14%), 8 (11), 3 (4%) respectively.

CONCLUSION

Cardiometabolic and bone morbidities are not uncommon in adults with CAH. There is a need to standardise the screening for these morbidities from early adulthood and to explore optimal therapy through routine collection of standardised data.

Cystathionine Beta-Synthase Deficiency: Three Consecutive Cases Detected in 40 Days by Newborn Screening in Emilia Romagna (Italy) and a Comprehensive Review of the Literature

Cysthiatonine beta-synthase (CBS) deficiency (CBSD) is an autosomal recessive rare disorder caused by variations on CBS that leads to impaired conversion of homocysteine (Hcy) to cystathionine. Marked hyperhomocysteinemia is the hallmark of the disease. The administration of pyridoxine, the natural cofactor of CBS, may reduce total plasma Hcy. Patient phenotype is classified on pyridoxine responsivity in two groups: pyridoxine-responsive and non-responsive patients. Ectopia lentis, bone deformities, developmental delay, and thromboembolism are the classic signs and symptoms of the disease. Early diagnosis and treatment impact patients' natural history. Therapy aims to lower promptly and maintain Hcy concentrations below 100 μmol/L. Depending on the patient's phenotype, the treatment goals could be obtained by the administration of pyridoxine and/or betaine associated with a methionine-restricted diet. CBSD could be diagnosed in the early days of life by expanded newborn screening (ENS), however, the risk of false negative results is not negligible. In Emilia-Romagna (Italy), during the first 10 years of screening experience, only three cases of CBSD identified have been diagnosed, all in the last two years (incidence 1:118,000 live births). We present the cases and a comprehensive review of the literature to emphasize the role of ENS for early diagnosis of CBSD and its potential pitfalls, reiterating the need for a more effective method to screen for CBSD.

Rare PHEX intron variant causes complete and severe phenotype in a family with hypophosphatemic rickets: a case report

OBJECTIVES

Lower limb deformities in children need careful orthopedic evaluation to distinguish physiological forms from pathological ones. X-linked hypophosphatemia (XLH) is a rare hereditary condition caused by PHEX gene mutations where tibial varum can be the first sign.

CASE PRESENTATION

We report a family presenting with severe tibial varum, harbouring a rare PHEX intron mutation, c.1586+6T>C. This is the first clinical description available in literature for this variant. Despite the previous prediction of a mild phenotype in functional study, our patients showed important bone deformities, rickets and impaired growth since infancy followed by severe bone pain, hearing loss and reduced life quality in adulthood. Burosumab therapy improved biochemical and radiological findings in children and ameliorated quality of life in adults.

CONCLUSIONS

This case demonstrated c.1586+6T>C causes a severe XLH phenotype, responsive to Burosumab. Familial genetic screening, enlarged to intronic region analysis, when XLH is suspected, allows precocious diagnosis to start timely the appropriate treatment.

Adrenal crisis in infants and young children with adrenal insufficiency: Management and prevention

BACKGROUND

Despite the optimization of replacement therapy, adrenal crises still represent life-threatening emergencies in many children with adrenal insufficiency.

OBJECTIVE

We summarized current standards of clinical practice for adrenal crisis and investigated the prevalence of suspected/incipient adrenal crisis, in relation to different treatment modalities, in a group of children with adrenal insufficiency.

RESULTS

Fifty-one children were investigated. Forty-one patients (32 patients <4 yrs and 9 patients >4 yrs) used quartered non-diluted 10 mg tablets. Two patients <4 yrs used a micronized weighted formulation obtained from 10 mg tablets. Two patients <4 yrs used a liquid formulation. Six patients >4 yrs used crushed non-diluted 10 mg tablets. The overall number of episodes of adrenal crisis was 7.3/patient/yr in patients <4yrs and 4.9/patient/yr in patients >4 yrs. The mean number of hospital admissions was 0.5/patient/yr in children <4 yrs and 0.53/patient/yr in children >4 yrs. There was a wide variability in the individual number of events reported. Both children on therapy with a micronized weighted formulation reported no episode of suspected adrenal crisis during the 6-month observation period.

CONCLUSION

Parental education on oral stress dosing and switching to parenteral hydrocortisone when necessary are the essential approaches to prevent adrenal crisis in children.

The genetic diagnosis of rare endocrine disorders of sex development and maturation: a survey among Endo-ERN centres

Differences of sex development and maturation (SDM) represent a heterogeneous puzzle of rare conditions with a large genetic component whose management and treatment could be improved by an accurate classification of underlying molecular conditions, and next-generation sequencing (NGS) should represent the most appropriate approach. Therefore, we conducted a survey dedicated to the use and potential outcomes of NGS for SDM disorders diagnosis among the 53 health care providers (HCP) of the European Reference Network for rare endocrine conditions. The response rate was 49% with a total of 26 HCPs from 13 countries. All HCPs, except 1, performed NGS investigations for SDM disorders on 6720 patients, 3764 (56%) with differences of sex development (DSD), including 811 unexplained primary ovarian insufficiency, and 2956 (44%) with congenital hypogonadotropic hypogonadism (CHH). The approaches varied from targeted analysis of custom gene panels (range: 11-490 genes) in 81.5% of cases or whole exome sequencing with the extraction of a virtual panel in the remaining cases. These analyses were performed for diagnostic purposes in 21 HCPs, supported by the National Health Systems in 16 cases. The likelihood of finding a variant ranged between 7 and 60%, mainly depending upon the number of analysed genes or criteria used for reporting, most HCPs also reporting variants of uncertain significance. These data illustrate the status of genetic diagnosis of DSD and CHH across Europe. In most countries, these analyses are performed for diagnostic purposes, yielding highly variable results, thus suggesting the need for harmonization and general improvements of NGS approaches.

Analysis of therapy monitoring in the International Congenital Adrenal Hyperplasia Registry

OBJECTIVE

Congenital adrenal hyperplasia (CAH) requires exogenous steroid replacement. Treatment is commonly monitored by measuring 17-OH progesterone (17OHP) and androstenedione (D4).

DESIGN

Retrospective cohort study using real-world data to evaluate 17OHP and D4 in relation to hydrocortisone (HC) dose in CAH patients treated in 14 countries.

PATIENTS

Pseudonymized data from children with 21-hydroxylase deficiency (21OHD) recorded in the International CAH Registry.

MEASUREMENTS

Assessments between January 2000 and October 2020 in patients prescribed HC were reviewed to summarise biomarkers 17OHP and D4 and HC dose. Longitudinal assessment of measures was carried out using linear mixed-effects models (LMEM).

RESULTS

Cohort of 345 patients, 52.2% female, median age 4.3 years (interquartile range: 3.1-9.2) were taking a median 11.3 mg/m2 /day (8.6-14.4) of HC. Median 17OHP was 35.7 nmol/l (3.0-104.0). Median D4 under 12 years was 0 nmol/L (0-2.0) and above 12 years was 10.5 nmol/L (3.9-21.0). There were significant differences in biomarker values between centres (p < 0.05). Correlation between D4 and 17OHP was good in multiple regression with age (p < 0.001, R2  = 0.29). In longitudinal assessment, 17OHP levels did not change with age, whereas D4 levels increased with age (p < 0.001, R2  = 0.08). Neither biomarker varied directly with dose or weight (p > 0.05). Multivariate LMEM showed HC dose decreasing by 1.0 mg/m2 /day for every 1 point increase in weight standard deviation score.

DISCUSSION

Registry data show large variability in 17OHP and D4 between centres. 17OHP correlates with D4 well when accounting for age. Prescribed HC dose per body surface area decreased with weight gain.

Prenatal dexamethasone treatment for classic 21-hydroxylase deficiency in Europe

OBJECTIVE

To assess the current medical practice in Europe regarding prenatal dexamethasone (Pdex) treatment of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency.

DESIGN AND METHODS

A questionnaire was designed and distributed, including 17 questions collecting quantitative and qualitative data. Thirty-six medical centres from 14 European countries responded and 30 out of 36 centres were reference centres of the European Reference Network on Rare Endocrine Conditions, EndoERN.

RESULTS

Pdex treatment is currently provided by 36% of the surveyed centres. The treatment is initiated by different specialties, that is paediatricians, endocrinologists, gynaecologists or geneticists. Regarding the starting point of Pdex, 23% stated to initiate therapy at 4-5 weeks postconception (wpc), 31% at 6 wpc and 46 % as early as pregnancy is confirmed and before 7 wpc at the latest. A dose of 20 µg/kg/day is used. Dose distribution among the centres varies from once to thrice daily. Prenatal diagnostics for treated cases are conducted in 72% of the responding centres. Cases treated per country and year vary between 0.5 and 8.25. Registries for long-term follow-up are only available at 46% of the centres that are using Pdex treatment. National registries are only available in Sweden and France.

CONCLUSIONS

This study reveals a high international variability and discrepancy in the use of Pdex treatment across Europe. It highlights the importance of a European cooperation initiative for a joint international prospective trial to establish evidence-based guidelines on prenatal diagnostics, treatment and follow-up of pregnancies at risk for CAH.

Management of Childhood-onset Craniopharyngioma in Italy: A Multicenter, 7-Year Follow-up Study of 145 Patients

CONTEXT

Nationwide data on children diagnosed with craniopharyngioma (CP) are not available in Italy.

OBJECTIVE

This work aimed to identify patients' characteristics, type of surgical approach, complications and recurrences, number of pituitary deficits, and number of patients starting growth hormone (GH) treatment.

METHODS

A retrospective multicenter collection took place of 145 patients aged 0 to 18 years who underwent surgery for CP between 2000 and 2018, and followed up in 17 Italian centers of pediatric endocrinology.

RESULTS

Age at diagnosis was 8.4 ± 4.1 years. Duration of symptoms was 10.8 ± 12.5 months and headache was most frequent (54%), followed by impaired growth (48%) and visual disturbances (44%). Most lesions were suprasellar (85%), and histology was adamantinomatous in all cases but two. Surgical approach was transcranial (TC) in 67.5% of cases and transsphenoidal (TS) in 31.%. The TC approach was prevalent in all age groups. Postsurgery complications occurred in 53% of cases, with water-electrolyte disturbances most frequent. Radiotherapy was used in 39% of cases. All patients but one presented with at least one hormone pituitary deficiency, with thyrotropin deficiency most frequent (98.3%), followed by adrenocorticotropin (96.8%), arginine vasopressin (91.1%), and GH (77.4%). Body mass index (BMI) significantly increased over time. A hypothalamic disturbance was present in 55% of cases. GH therapy was started during follow-up in 112 patients at a mean age of 10.6 years, and 54 developed a recurrence or regrowth of the residual lesion.

CONCLUSION

CP is often diagnosed late in Italy, with TC more frequent than the TS surgical approach. Postsurgery complications were not rare, and hypopituitarism developed almost in all cases. BMI shows a tendency to increase overtime.

Growth, puberty and testicular function in boys born small for gestational age with a nonspecific disorder of sex development

OBJECTIVE

Being born small for gestational age (SGA) is frequently associated with unexplained disorders of sex development (nonspecific DSD) in boys. Little is known about their future growth, puberty and testicular function. Our objective is to determine the long-term endocrine outcome of boys born SGA who have a nonspecific DSD.

DESIGN

Boys with a nonspecific DSD born SGA and appropriate for GA (AGA) were retrieved through the International Disorders of Sex Development registry and retrospective data collected, based on a spreadsheet containing 102 items.

PATIENTS AND MEASUREMENTS

In total, 179 boys were included, of which 115 were born SGA and 64 were born AGA. Their growth and pubertal development were compared. Serum LH, FSH, testosterone, AMH and inhibin B levels in infancy and puberty were analysed to assess testicular function.

RESULTS

At 2 years of age, 30% of SGA boys had incomplete or absent catch-up growth. Boys born SGA also had higher LH during minipuberty and lower testosterone in stimulation tests (p = 0.037 and 0.040, respectively), as compared to boys born AGA. No differences were observed in timing or course of puberty or end-pubertal hormone levels.

CONCLUSIONS

Almost one out of three SGA boys with a nonspecific DSD experiences insufficient catch-up growth. In addition, our data suggest dysfunction of infantile Leydig cells or altered regulation of the hypothalamic-pituitary-gonadal axis in SGA boys during childhood. Sex steroid production during puberty seems unaffected.

Proposal of an Algorithm to Early Detect Attenuated Type I Mucopolysaccharidosis (MPS Ia) among Children with Growth Abnormalities

Background and Objectives: Diagnostic delay is common in attenuated Mucopolysaccharidosis Type I (MPS Ia) due to the rarity of the disease and the variability of clinical presentation. Short stature and impaired growth velocity are frequent findings in MPS Ia, but they rarely raise suspicion as paediatric endocrinologists are generally poorly trained to detect earlier and milder clinical signs of this condition. Materials and Methods: Following a consensus-based methodology, a multidisciplinary panel including paediatric endocrinologists, paediatricians with expertise in metabolic disorders, radiologists, and rheumatologists shared their experience on a possible clinical approach to the diagnosis of MPS Ia in children with short stature or stunted growth. Results: The result was the formation of an algorithm that illustrates how to raise the suspicion of MPS Ia in a patient older than 5 years with short stature and suggestive clinical signs. Conclusion: The proposed algorithm may represent a useful tool to improve the awareness of paediatric endocrinologists and reduce the diagnostic delay for patients with MPS Ia.

Evidence for a Genotype-Phenotype Correlation in Patients with Pathogenic GLUT2 (SLC2A2) Variants

Fanconi-Bickel syndrome (FBS) is a very rare but distinct clinical entity with the combined features of hepatic glycogen storage disease, generalized proximal renal tubular dysfunction with disproportionately severe glucosuria, and impaired galactose tolerance. Here, we report five cases (out of 93 diagnosed in our lab) with pathogenic variants on both GLUT2 (SLC2A2) alleles. They come from 3 families and presented with an exceptionally mild clinical course. This course was correlated to data from old and most recent expression and transport studies in Xenopus oocytes. GLUT2 genotype in patients 1 and 2 was p.[153_4delLI];[P417R] with the first variant exhibiting normal membrane expression and partially retained transport activity (5.8%) for 2-deoxyglucose. In patient 3, the very first GLUT2 variant ever detected (p.V197I) was found, but for the first time it was present in a patient in the homozygous state. This variant had also shown unaffected membrane expression and remarkable residual activity (8%). The genotype in patient 4, p.[153_4delLI];[(E440A)], again included the 2-amino-acid deletion with residual transporter function, and patient 5 is the first found to be homozygous for this variant. Our results provide further evidence for a genotype-phenotype correlation in patients with GLUT2 variants; non-functional variants result in the full picture of FBS while dysfunctional variants may result in milder presentations, even glucosuria only, without other typical signs of FBS.

Transient central precocious puberty: a new entity among the spectrum of precocious puberty?

Objective

Recently, we observed some cases of Precocious Puberty (PP) with a partial central activation of hypothalamic-pituitary-gonadal (HPG) axis that tended to normalized in 6–12 months. To evaluate the frequency of this form within the spectrum of forms of PP, we retrospectively assessed the clinical, hormonal and ultrasound characteristics of patients attending to our Center for signs of PP, between 2007 and 2017. To hypothesize some causes of this “pubertal poussée” a questionnaire about environmental data was provided to patients.

Methods

96 girls were recruited for the study and divided into three Groups. Group 1: 56 subjects with Central PP (CPP) requiring treatment with GnRH analogue; Group 2: 22 subjects with transient activation of pubertal axis, that tended to normalize, “Transient CPP”(T-CPP); Group 3: 18 subjects with Isolated Thelarche (IT).

Results

Mean age at diagnosis was 6.8 ± 1.0 years in Group 1, 5.9 ± 1.3 years in Group 2 and 5.6 ± 1.5 years in Group 3. A significant increase of diagnosis of T-CPP was observed over the study period. Significantly higher use of some homeopathic medicines and potential exposure to pesticides was reported in Group 2 vs Group 1.

Conclusions

To our knowledge, we first reported a form defined as T-CPP, characterized by partial activation in the HPG axis normalizing over time. An increased use of homeopathic medicines and exposure to environmental pollutants in these patients was evidenced.

Phenotypic diversity, disease progression, and pathogenicity of MVK missense variants in mevalonic aciduria

Mevalonic aciduria (MVA) and hyperimmunoglobulinemia D syndrome (MKD/HIDS) are disorders of cholesterol biosynthesis caused by variants in the MVK gene and characterized by increased urinary excretion of mevalonic acid. So far, 30 MVA patients have been reported, suffering from recurrent febrile crises and neurologic impairment. Here, we present an in-depth analysis of the phenotypic spectrum of MVA and provide an in-silico pathogenicity model analysis of MVK missense variants. The phenotypic spectrum of 11 MVA patients (age range 0-51 years) registered in the Unified European Registry for Inherited Metabolic Disorders database was systematically analyzed using terms of the Human Phenotype Ontology. Biochemical, radiological as well as genetic characteristics were investigated. Six of eleven patients have reached adulthood and four have reached adolescence. One of the adolescent patients died at the age of 16 years and one patient died shortly after birth. Symptoms started within the first year of life, including episodic fever, developmental delay, ataxia, and ocular involvement. We also describe a case with absence of symptoms despite massive excretion of mevalonic acid. Pathogenic variants causing MVA cluster within highly conserved regions, which are involved in mevalonate and ATP binding. The phenotype of adult and adolescent MVA patients is more heterogeneous than previously assumed. Outcome varies from an asymptomatic course to early death. MVK variants cluster in functionally important and highly conserved protein domains and show high concordance regarding their expected pathogenicity.

Growth Trajectory and Adult Height in Children with Nonclassical Congenital Adrenal Hyperplasia

BACKGROUND

Children with nonclassical congenital adrenal hyperplasia (NCCAH) often present increased growth velocity secondary to elevation of adrenal androgens that accelerates bone maturation and might compromise adult height (AH).

OBJECTIVE

The aim of the study was to analyze prognostic factors affecting growth trajectory (GT) and AH in children with NCCAH.

METHODS

The study was a retrospective, multicentric study. The study population consisted of 192 children with a confirmed molecular diagnosis of NCCAH, followed by pediatric endocrinology centers from diagnosis up to AH. Clinical records were collected and analyzed. AH (standard deviation score; SDS), pubertal growth (PG) (cm), GT from diagnosis to AH (SDS), and AH adjusted to target height (TH) (AH-TH SDS) were evaluated as outcome indicators using stepwise linear regression models.

RESULTS

The stepwise linear regression analysis showed that AH and AH-TH were significantly related to chronological age (CA) (p = 0.008 and 0.016), bone age (BA)/CA ratio (p = 0.004 and 0.001), height (H) (p < 0.001 for both parameters) at NCCAH diagnosis, and TH (p = 0.013 and <0.001). PG was higher in males than in females (22.59 ± 5.74 vs. 20.72 ± 17.4 cm, p = 0.002), as physiologically observed, and was positively related to height (p = 0.027), negatively to BMI (p = 0.001) and BA/CA ratio (p = 0.001) at NCCAH diagnosis. Gender, genotype, biochemical data, and hydrocortisone treatment did not significantly impair height outcomes of these NCCAH children.

CONCLUSIONS

The results of this study suggest that AH and GT of NCCAH patients are mainly affected by the severity of phenotype (CA, BA/CA ratio, and H) at the time of diagnosis.

Differences of sex development in the newborn: from clinical scenario to molecular diagnosis

Differences/disorders of sex development (DSD) are defined as a group of congenital conditions in which the development of chromosomal, gonadal or anatomical sex is atypical. The incidence of DSD is 1:4500 births. The current classification divides DSDs into 3 categories according to chromosomal sex: 46,XX DSD, 46,XY DSD and sex chromosome DSD. DSD phenotypes can be concordant with the genotype (apparently normal external genitalia associated with gonadal dysgenesis), or can range from simply hypospadias to completely masculinised or feminised genitalia with a discordant karyotype. Numerous genes implicated in genital development have been reported. The search of genetic variants represents a central element of the extended investigation, as an improved knowledge of the genetic aetiology helps the immediate and long-term management of children with DSDs, in term of sex of rearing, hormone therapy, surgery, fertility and cancer risk. This review aims to assess the current role of molecular diagnosis in DSD management.

Gonadectomy in conditions affecting sex development: a registry-based cohort study

OBJECTIVES

To determine trends in clinical practice for individuals with DSD requiring gonadectomy.

DESIGN

Retrospective cohort study.

METHODS

Information regarding age at gonadectomy according to diagnosis; reported sex; time of presentation to specialist centre; and location of centre from cases reported to the International DSD Registry and who were over 16 years old in January 2019.

RESULTS

Data regarding gonadectomy were available in 668 (88%) individuals from 44 centres. Of these, 248 (37%) (median age (range) 24 (17, 75) years) were male and 420 (63%) (median age (range) 26 (16, 86) years) were female. Gonadectomy was reported from 36 centres in 351/668 cases (53%). Females were more likely to undergo gonadectomy (n = 311, P < 0.0001). The indication for gonadectomy was reported in 268 (76%). The most common indication was mitigation of tumour risk in 172 (64%). Variations in the practice of gonadectomy were observed; of the 351 cases from 36 centres, 17 (5%) at 9 centres had undergone gonadectomy before their first presentation to the specialist centre. Median age at gonadectomy of cases from high-income countries and low-/middle-income countries (LMIC) was 13.0 years (0.1, 68) years and 16.5 years (1, 28), respectively (P < 0.0001) with the likelihood of long-term retention of gonads being higher in LMIC countries.

CONCLUSIONS

The likelihood of gonadectomy depends on the underlying diagnosis, sex of rearing and the geographical setting. Clinical benchmarks, which can be studied across all forms of DSD will allow a better understanding of the variation in the practice of gonadectomy.

Growth-Related Characteristics of Patients &lt;18 Years of Age with Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency (21OHD): Real World Evidence from the I-CAH Registry

Background: Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21OHD) is a rare, autosomal recessive disease of the adrenal cortex leading to a lack of cortisol production and compensatory ACTH secretion, which drives excess androgen production. The chronic exposure to excess androgen, coupled with supraphysiologic glucocorticoid doses, can lead to advanced skeletal maturation with reduced growth in puberty, premature epiphyseal closure, and shorter final adult height. The I-CAH Registry, launched in 2007, currently has >1500 cases of CAH from 26 countries. Aim of the current study was to identify growth-related characteristics of children and adolescents with 21OHD CAH registered in the I-CAH registry and who were based in Europe. Methods: The I-CAH registry was queried on 8-Oct-2019 using the following criteria: CYP21A enzyme deficiency; European site, male or female, age <18 years; and ≥1 growth-related assessment. Descriptive analyses were conducted using data from all patient visits, with age subgroups defined as follows: 0 to <2 years (0-2yr), 2 to 11 years (2-11yr), and 12 to 17 years (12-17yr). Since I-CAH data are longitudinal, patients who aged during registry enrollment may be included in >1 subgroup. Analyses included standard deviation scores (SDS) for patients’ height for chronological age (CA), weight for CA, and height for bone age (BA) using World Health Organization growth chart data for reference values. Results: Of 232 patients in 10 European countries, 126 (54%) were female and most were from Germany (25%), United Kingdom (23%), Netherlands (14%), and Italy (11%). The 232 patients had a total of 2042 visits, with 44% (900 visits) in the 0-2yr group, 42% (860 visits) in the 2-11yr group, and 14% (282 visits) in the 12-17yr group. No discernible pattern by age group was found for height for CA based on mean/median SDS scores. For weight for CA, mean/median SDS scores showed an increasing trend in older patients: 0-2yr (0.22/-0.06 [896 visits]); 2-11yr (0.47/0.55 [855 visits]); and 12-17yr (0.55/0.66 [278 visits]). Mean/median SDS scores for height for BA decreased with age: 0-2yr (0.31/0.05 [36 visits]); 2-11yr (-0.32/-0.23 [172 visits]); and 12-17yr (-0.49/-0.26 [44 visits]). Paired BA and CA values from 259 patient visits showed a trend towards bone age being greater than CA, starting at approximately 48 months of age and leveling out around 120-130 months. Mean BA was advanced by 9.7 months compared to CA (SD: 21.2 months, 95%; CI: 7.1 to 12.3 months, [p<0.0001]). Conclusions: As previous research has indicated, I-CAH registry data suggest that children and adolescents with classic 21OHD CAH in Europe have advanced BA relative to CA, with height relative to BA tending to decrease with older age. The I-CAH registry offers the opportunity to study a variety of growth determinants and measurements with an option for subgroup analysis.

Primary Adrenal Insufficiency in Childhood: Data From a Large Nationwide Cohort

CONTEXT

Primary adrenal insufficiency (PAI) is a rare and potentially life-threatening condition that is poorly characterized in children.

OBJECTIVE

To describe causes, presentation, auxological outcome, frequency of adrenal crisis and mortality of a large cohort of children with PAI.

PATIENTS AND METHODS

Data from 803 patients from 8 centers of Pediatric Endocrinology were retrospectively collected.

RESULTS

The following etiologies were reported: 85% (n = 682) congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD); 3.1% (n = 25) X-linked adrenoleukodystrophy; 3.1% (n = 25) autoimmune polyglandular syndrome type 1; 2.5% (n = 20) autoimmune adrenal insufficiency; 2% (n = 16) adrenal hypoplasia congenital; 1.2% (n = 10) non-21-OHD CAH; 1% (n = 8) rare syndromes; 0.6% (n = 5) familial glucocorticoid deficiency; 0.4% (n = 3) acquired adrenal insufficiency; 9 patients (1%) did not receive diagnosis. Since 21-OHD CAH has been extensively characterized, it was not further reviewed. In 121 patients with a diagnosis other than 21-OHD CAH, the most frequent symptoms at diagnosis were fatigue (67%), hyperpigmentation (50.4%), dehydration (33%), and hypotension (31%). Elevated adrenocorticotropic hormone (96.4%) was the most common laboratory finding followed by hyponatremia (55%), hyperkalemia (32.7%), and hypoglycemia (33.7%). The median age at presentation was 6.5 ± 5.1 years (0.1-17.8 years) and the mean duration of symptoms before diagnosis was 5.6 ± 11.6 months (0-56 months) depending on etiology. Rate of adrenal crisis was 2.7 per 100 patient-years. Three patients died from the underlying disease. Adult height, evaluated in 70 patients, was -0.70 ± 1.20 standard deviation score.

CONCLUSIONS

We characterized one of the largest cohorts of children with PAI aiming to improve the knowledge on diagnosis of this rare condition.

Prevalence and ultrasound patterns of testicular adrenal rest tumors in adults with congenital adrenal hyperplasia

Background

Testicular adrenal rest tumors (TARTs) are benign neoplasms affecting patients with congenital adrenal hyperplasia (CAH). The prevalence of TART in adult patients with CAH is not well known. Ultrasonography (US) is the main tool for diagnosing TART and the role of contrast-enhanced US (CEUS) is never investigated. The aim of this study was to evaluate the TART prevalence in adults with CAH, by stratifying patients according to disease phenotype and assessing the diagnostic performance of US, color Doppler (CD) US and CEUS.

Methods

Male patients >16 years old with certain diagnosis of CAH who underwent US for TARTs, between December 2015 and September 2019 were prospectively enrolled. The control group included patients without CAH affected by testicular lesions at US other than TARTs.

Results

TARTs were identified in 16 of 52 patients (31%), of whom 15 (93.8%) displayed the salt-wasting (SW) form (P<0.001). The prevalence of TARTs in patients with the SW form was 54%. One patient with the non-classic (NC) form (6%) showed TART (likely the first documented case). The mean age of patients upon detection of TARTs was significantly younger compared with the control group (P<0.001); moreover, TARTs were bilateral in 15/16 patients (93.8%; P<0.001) and the largest lesion was more frequent in the medium third of testis in the TART group (87.5%), statistically different from the control group (P=0.013).

Conclusions

TARTs almost exclusively affected patients with the SW form of CAH. Age at diagnosis and bilateralism are useful factors for achieving a correct diagnosis of TARTs in CAH adult patients.

Testosterone Therapy and Its Monitoring in Adolescent Boys with Hypogonadism: Results of an International Survey from the I-DSD Registry

It is unclear whether testosterone replacement therapy (TRT) in adolescent boys, affected by a range of endocrine diseases that may be associated with hypogonadism, is particularly common. The aim of this study was to assess the contemporary practice of TRT in boys included in the I-DSD Registry. All participating centres in the I-DSD Registry that had boys between 10 and 18 years of age and with a condition that could be associated with hypogonadism were invited to provide further information in 2019. Information on 162 boys was collected from 15 centres that had a median (range) number of 6 boys per centre (1.35). Of these, 30 (19%) from 9 centres were receiving TRT and the median (range) age at the start was 12.6 years (10.8-16.2), with 6 boys (20%) starting at <12 years. Median (range) age of boys not on TRT was 11.7 years (10.7-17.7), and 69 out of 132 (52%) were <12 years. TRT had been initiated in 20 of 71 (28%) boys with a disorder of gonadal development, 3 of 14 (21%) with a disorder of androgen synthesis, and all 7 (100%) boys with hypogonadotropic hypogonadism. The remainder who did not have TRT included 15 boys with partial androgen insensitivity, 52 with non-specific XY DSD, and 3 with persistent Müllerian duct syndrome. Before starting TRT, liver function and blood count were checked in 19 (68%) and 18 boys (64%), respectively, a bone age assessment was performed in 23 (82%) and bone mineral density assessment in 12 boys (43%). This snapshot of contemporary practice reveals that TRT in boys included in the I-DSD Registry is not very common, whilst the variation in starting and monitoring therapy is quite marked. Standardisation of practice may lead to more effective assessment of treatment outcomes.

Maternal PKU: Defining phenylalanine tolerance and its variation during pregnancy, according to genetic background

BACKGROUND AND AIMS

Phenylketonuria (PKU)-affected women may become pregnant, and dietary phenylalanine (Phe) intake must be adjusted according to Phe tolerance. We report our experience with maternal PKU in relation to genotype PKU heterogeneity.

METHODS AND RESULTS

A total of 10 pregnancies in 7 PKU women (7 different genotypes) were followed up as part of personalized care. Phe tolerance during preconception and pregnancy was assessed by strict dietary control and weekly Phe measurement (blood spots) in relation to genotype. Most women had stopped PKU diet during childhood or adolescence and six pregnancies were unplanned; a phenylalanine-restricted diet was reinstituted soon after conception. Women were classified according to their Phe levels at birth screening and genotype. Phe tolerance increased systematically in the course of pregnancy in all cases, but the increase was different in subjects with classic PKU (cPKU) when compared with cases with mild hyperphenylalaninemia (mHPA), both on average (+297 mg/day in cPKU vs. 597 in mHPA; P = 0.017) and as percentage (+107% in cPKU vs. +17% in mHPA). Notably, Phe tolerance also varied in the same women in the course of different pregnancies, when body weight gain was also different. Two newborns from the same cPKU mother (unplanned pregnancies on free diet) were affected by congenital alterations.

CONCLUSIONS

Several factors influence metabolic phenotype in maternal PKU, to an unpredictable extent even in the same woman. The number of maternal PKU cases is growing in dedicated Nutrition Units, and the burden associated with careful management of this condition for the health care system should be adequately considered.

Congenital Adrenal Hyperplasias Presenting in the Newborn and Young Infant

Congenital adrenal hyperplasia includes autosomal recessive conditions that affect the adrenal cortex steroidogenic enzymes (cholesterol side-chain cleavage enzyme; 3β-hydroxysteroid dehydrogenase; 17α-hydroxylase/17,20 lyase; P450 oxidoreductase; 21-hydroxylase; and 11β-hydroxylase) and proteins (steroidogenic acute regulatory protein). These are located within the three major pathways of the steroidogenic apparatus involved in the production of mineralocorticoids, glucocorticoids, and androgens. Many countries have introduced newborn screening program (NSP) based on 17-OH-progesterone (17-OHP) immunoassays on dried blood spots, which enable faster diagnosis and treatment of the most severe forms of 21-hydroxylase deficiency (21-OHD). However, in several others, the use of this diagnostic tool has not yet been implemented and clinical diagnosis remains challenging, especially for males. Furthermore, less severe classic forms of 21-OHD and other rarer types of CAHs are not identified by NSP. The aim of this mini review is to highlight both the main clinical characteristics and therapeutic options of these conditions, which may be useful for a differential diagnosis in the neonatal period, while contributing to the biochemical evolution taking place in the steroidogenic field. Currently, chromatographic techniques coupled with tandem mass spectrometry are gaining attention due to an increase in the reliability of the test results of NPS for detecting 21-OHD. Furthermore, the possibility of identifying CAH patients that are not affected by 21-OHD but presenting elevated levels of 17-OHP by NSP and the opportunity to include the recently investigated 11-oxygenated androgens in the steroid profiles are promising tools for a more precise diagnosis and monitoring of some of these conditions.

Plasma Renin Measurements are Unrelated to Mineralocorticoid Replacement Dose in Patients With Primary Adrenal Insufficiency

CONTEXT

No consensus exists for optimization of mineralocorticoid therapy in patients with primary adrenal insufficiency.

OBJECTIVE

To explore the relationship between mineralocorticoid (MC) replacement dose, plasma renin concentration (PRC), and clinically important variables to determine which are most helpful in guiding MC dose titration in primary adrenal insufficiency.

DESIGN

Observational, retrospective, longitudinal analysis.

PATIENTS

A total of 280 patients (with 984 clinical visits and plasma renin measurements) with primary adrenal insufficiency were recruited from local databases and the international congenital adrenal hyperplasia (CAH) registry (www.i-cah.org). Thirty-seven patients were excluded from the final analysis due to incomplete assessment. Data from 204 patients with salt-wasting CAH (149 adults and 55 children) and 39 adult patients with Addison disease (AD) were analysed.

MAIN OUTCOME MEASURES

PRC, electrolytes, blood pressure (BP), and anthropometric parameters were used to predict their utility in optimizing MC replacement dose.

RESULTS

PRC was low, normal, or high in 19%, 36%, and 44% of patients, respectively, with wide variability in MC dose and PRC. Univariate analysis demonstrated a direct positive relationship between MC dose and PRC in adults and children. There was no relationship between MC dose and BP in adults, while BP increased with increasing MC dose in children. Using multiple regression modeling, sodium was the only measurement that predicted PRC in adults. Longitudinally, the change in MC dose was able to predict potassium, but not BP or PRC.

CONCLUSIONS

The relationship between MC dose and PRC is complex and this may reflect variability in sampling with respect to posture, timing of last MC dose, adherence, and concomitant medications. Our data suggest that MC titration should not primarily be based only on PRC normalization, but also on clinical parameters such as BP and electrolyte concentration.

X-linked hypophosphatemic rickets: an Italian experts' opinion survey

Background

X-linked hypophosphatemic rickets (XLH) is the first cause of inherited hypophosphatemia and is caused by mutation in the PHEX gene, resulting in excessive expression of the phosphaturic factor FGF23. Symptoms are mainly related to rickets in children and osteomalacia in adults and cause several complications that can be highly invalidating. Due to its rarity, XLH is poorly known and diagnosis is frequently delayed. Conventional treatment is based on oral phosphate salts supplementation and activated vitamin D analogs, which however, cannot cure the disease in most cases.

Objective

Due to the low prevalence of XLH, an experts’ opinion survey was conducted across Italian centers to collect data on XLH and on its management.

Methods

A questionnaire was developed by a group of experts to collect data on XLH epidemiology, diagnosis and treatment in Italy.

Results

Data from 10 Italian centers (nine of which pediatric) on 175 patients, followed between 1998 and 2017, were included in the survey. Most patients were followed since childhood and 63 children became adults during the investigated period. The diagnosis was made before the age of 1 and between 1 and 5 years in 11 and 50% of cases, respectively. Clinically apparent bone deformities were present in 95% of patients. These were ranked moderate/severe in 75% of subjects and caused growth stunting in 67% of patients. Other frequent complications included bone pain (40%), dental abscesses (33%), and dental malpositions (53%). Treatment protocols varied substantially among centers. Nephrocalcinosis was observed in 34% of patients. Tertiary hyperparathyroidism developed in 6% of patients.

Conclusions

XLH remains a severe condition with significant morbidities.

Mutational and functional studies on NR5A1 gene in 46,XY disorders of sex development: identification of six novel loss of function mutations

OBJECTIVE

To study the functional properties of six novel missense mutations of the NR5A1 gene encoding the steroidogenic factor 1 (SF-1) identified in six patients with 46,XY disorders of sex development (DSD) and to describe their relative phenotype-genotype relationship.

DESIGN

Genetic and functional studies.

SETTING

University department.

PATIENT(S)

Six 46,XY DSD patients.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Sanger sequencing and multiplex ligation-dependent probe amplification analysis to identify the mutations or deletions/duplications of the NR5A1 gene. Functional studies by transactivation assays to predict the impact of mutations on molecular function.

RESULT(S)

NR5A1 exons sequencing identified in six 46,XY DSD patients six novel mutations: p.T40R, p.T47C, p.G328W, p.A351E, p.R427W, and p.Q460R. Five missense variants were heterozygous, and one was homozygous (p.R427W). Functional analysis revealed a significant loss of DNA-binding and transactivation ability for all variants, except for p.Q460R, which showed a modest reduced activity compared with that of the wild-type protein. Phenotypes associated with these mutations varied from males with spontaneous puberty, substantial T production, and possible fertility, to females with and without müllerian structures and primary amenorrhea.

CONCLUSION(S)

We describe six novel mutations in NR5A1 gene and showed that they might affect protein structure, therefore compromising seriously the SF-1 role in regulating gonadal development. Clinically, we suggest that NR5A1 analysis should be performed whenever atypical sex organs are evidenced or there is an abnormal sexual development, to have proper diagnosis and better management of patients.

Long-term renal outcome in children with OCRL mutations: retrospective analysis of a large international cohort

Background

Lowe syndrome (LS) and Dent-2 disease (DD2) are disorders associated with mutations in the OCRL gene and characterized by progressive chronic kidney disease (CKD). Here, we aimed to investigate the long-term renal outcome and identify potential determinants of CKD and its progression in children with these tubulopathies.

Methods

Retrospective analyses were conducted of clinical and genetic data in a cohort of 106 boys (LS: 88 and DD2: 18). For genotype-phenotype analysis, we grouped mutations according to their type and localization. To investigate progression of CKD we used survival analysis by Kaplan-Meier method using stage 3 CKD as the end-point.

Results

Median estimated glomerular filtration rate (eGFR) was lower in the LS group compared with DD2 (58.8 versus 87.4 mL/min/1.73 m2, P < 0.01). CKD stage II-V was found in 82% of patients, of these 58% and 28% had moderate-to-severe CKD in LS and DD2, respectively. Three patients (3%), all with LS, developed stage 5 of CKD. Survival analysis showed that LS was also associated with a faster CKD progression than DD2 (P < 0.01). On multivariate analysis, eGFR was dependent only on age (b = -0.46, P < 0.001). Localization, but not type of mutations, tended to correlate with eGFR. There was also no significant association between presence of nephrocalcinosis, hypercalciuria, proteinuria and number of adverse clinical events and CKD.

Conclusions

CKD is commonly found in children with OCRL mutations. CKD progression was strongly related to the underlying diagnosis but did not associate with clinical parameters, such as nephrocalcinosis or proteinuria.

Statistics of vector Manakov rogue waves

We present a statistical analysis based on the height and return-time probabilities of high-amplitude wave events in both focusing and defocusing Manakov systems. We find that analytical rational or semirational solutions, associated with extreme, rogue wave (RW) structures, are the leading high-amplitude events in this system. We define the thresholds for classifying an extreme wave event as a RW. Our results indicate that there is a strong relationship between the type of RW and the mechanism which is responsible for its creation. Initially, high-amplitude events originate from modulation instability. Upon subsequent evolution, the interaction among these events prevails as the mechanism for RW creation. We suggest a strategy for confirming the basic properties of different extreme events. This involves the definition of proper statistical measures at each stage of the RW dynamics. Our results point to the need for redefining criteria for identifying RW events.

The Influence of Growth Hormone Treatment on Glucose Homeostasis in GrowthHormone-Deficient Children: A Six-Year Follow-Up Study

BACKGROUND

Growth hormone (GH) influences glucose homeostasis by negatively affecting insulin sensitivity, leading to a compensatory increase in insulin secretion. It has recently been reported, in animals and humans, that GH might also stimulate insulin secretion by directly affecting the growth and function of pancreatic β-cells. The aim of this work was to longitudinally study the insulin sensitivity (HOMA-S), insulin secretion [insulinogenic index (IGI)] and capacity of β-cells to adapt to changes in insulin sensitivity [oral disposition index (ODI)] in GH-deficient (GHD) children under GH treatment.

METHODS

We studied 99 GHD (62 male, 37 female; age 8.9 ± 3.5 years) children for a median period of 6 years (range 1.5-16.2). Every year, our patients underwent an oral glucose tolerance test, which was used to calculate the HOMA-S, IGI and ODI.

RESULTS

Although HOMA-S remained unchanged, an increase in IGI and ODI was observed, becoming significant after 6 years of treatment (1.25 ± 1.28 vs. 2.35 ± 2.38, p < 0.05 and 0.57 ± 0.68 vs. 1.50 ± 1.92, p < 0.01, respectively).

CONCLUSION

Our results suggest a positive influence of GH treatment on the β-cell secretory capacity in children with GH deficiency. © 2016 S. Karger AG, Basel.

The Influence of GH Treatment on Glucose Homeostasis in Girls With Turner Syndrome: A 7-Year Study

CONTEXT

Growth hormone (GH) influences glucose homeostasis mainly by negatively affecting insulin sensitivity.

OBJECTIVE

To longitudinally study insulin sensitivity [via homeostasis model assessment of insulin sensitivity (HOMA-S)], insulin secretion [insulinogenic index (IGI)], and capacity of β cells to adapt to changes in insulin sensitivity [oral disposition index (ODI)] in girls with Turner syndrome (TS) undergoing GH treatment.

DESIGN AND SETTING

Longitudinal, retrospective, 7-year study conducted in a tertiary pediatric endocrine unit and university pediatric clinic.

PATIENTS AND METHODS

We studied 104 patients with TS (mean age ± standard deviation, 9.1 ± 3.4 years) for a median of 7.2 years.

INTERVENTION

Every year, the children underwent an oral glucose tolerance test, which was used to calculate HOMA-S, IGI, and ODI.

RESULTS

HOMA-S, IGI, and ODI did not significantly change.

CONCLUSION

The results are reassuring, showing no negative influence of GH treatment on insulin sensitivity and on β-cell secretory capacity in girls with TS.

Mudd's disease (MAT I/III deficiency): a survey of data for MAT1A homozygotes and compound heterozygotes

BACKGROUND

This paper summarizes the results of a group effort to bring together the worldwide available data on patients who are either homozygotes or compound heterozygotes for mutations in MAT1A. MAT1A encodes the subunit that forms two methionine adenosyltransferase isoenzymes, tetrameric MAT I and dimeric MAT III, that catalyze the conversion of methionine and ATP to S-adenosylmethionine (AdoMet). Subnormal MAT I/III activity leads to hypermethioninemia. Individuals, with hypermethioninemia due to one of the MAT1A mutations that in heterozygotes cause relatively mild and clinically benign hypermethioninemia are currently often being flagged in screening programs measuring methionine elevation to identify newborns with defective cystathionine β-synthase activity. Homozygotes or compound heterozygotes for MAT1A mutations are less frequent. Some but not all, such individuals have manifested demyelination or other CNS abnormalities.

PURPOSE OF THE STUDY

The goals of the present effort have been to determine the frequency of such abnormalities, to find how best to predict whether they will occur, and to evaluate the outcomes of the variety of treatment regimens that have been used. Data have been gathered for 64 patients, of whom 32 have some evidence of CNS abnormalities (based mainly on MRI findings), and 32 do not have such evidence.

RESULTS AND DISCUSSION

The results show that mean plasma methionine concentrations provide the best indication of the group into which a given patient will fall: those with means of 800 μM or higher usually have evidence of CNS abnormalities, whereas those with lower means usually do not. Data are reported for individual patients for MAT1A genotypes, plasma methionine, total homocysteine (tHcy), and AdoMet concentrations, liver function studies, results of 15 pregnancies, and the outcomes of dietary methionine restriction and/or AdoMet supplementation. Possible pathophysiological mechanisms that might contribute to CNS damage are discussed, and tentative suggestions are put forth as to optimal management.

Zero focusing via competing nonlinearities in beta-barium-borate crystals

We investigate nonlinear focusing behavior of light beams propagating in beta-barium-borate crystals under mismatched second-harmonic generation. We clearly identify experimentally multiple self-focusing and defocusing regions against the orientation angle and the condition where competing quadratic and cubic nonlinearities perfectly compensate each other (zero-focusing point).

Severe hypoglycemic episodes: a persistent threat for children with Type 1 diabetes mellitus and their families

BACKGROUND

As lowering glycated hemoglobin (HbA1c) levels is still the main goal of insulin treatment, severe hypoglycemia (SH) remains a common experience in children with Type 1 diabetes mellitus (T1DM) and their families.

AIM

This study aims to evaluate the incidence and the clinical features of SH episodes in our Centre in the last 20 yr.

SUBJECTS AND METHODS

We analyzed SH incidence in 269 patients (pts) diagnosed from 1990 to 2010 (total follow-up 2212.9 pts/yr). Inclusion criteria were at least 3 visits/yr and 1-yr follow- up. SH episode was defined as any condition of low blood glucose requiring third-party assistance.

RESULTS

50.2% of patients experienced at least 1 SH episode for a total of 345 episodes. Whole incidence was 15.6/100 pts/yr, slightly different between first and second decade (12.6 vs 16.5, p=0.047). HbA1c at the time of SH was lower in the non-basal bolus group (7.4±1.3 vs 8.2±1.4; p=0.0001) and worsened 3 months later (p=0.0001). Impaired awareness was the main or only symptom in 43.5%. SH occurred at night in 32% of patients; they were significantly younger than those with SH at other times. Five SH episodes or more occurred in 8.1% of patients who presented a lower HbA1c, a younger age and shorter disease duration than the other patients. HbA1c at first SH was negatively correlated with number of SH (r=-0.20; p=0.05).

CONCLUSIONS

Despite the advent of new insulin regimens, we confirm that SH still represents a relevant risk and a current threat for patients with T1DM and their families.

Comparison between liquid and tablet formulations of levothyroxine in the initial treatment of congenital hypothyroidism

OBJECTIVE

To evaluate the effects of liquid (drops) and tablet formulations of levothyroxine in homogeneous groups of infants with congenital hypothyroidism (CH) as diagnosed through neonatal screening.

STUDY DESIGN

Forty-two consecutive infants with CH were subdivided into 2 groups consisting of infants with the severe or the moderate/mild form. For each form, the infants with CH were randomly assigned to receive liquid (group 1) or tablet (group 2) formulation. In all patients, thyroid function tests were performed before the beginning of therapy and at 15 and 30 days and at 3 and 6 months after the beginning of therapy.

RESULTS

In the severe form, after 15 days of treatment, serum thyrotropin (TSH) levels became normal in 8 of 9 patients in group 1 and in 5 of 9 patients in group 2; serum free triiodothyronine (fT3) levels were significantly higher in group 1 than in group 2; and serum fT4 levels were higher than the upper limit of the normal range in all patients in both groups. During the follow-up, there were significantly more patients with suppressed TSH concentrations in group 1 than in group 2. In the moderate/mild form, the patients of group 1 and group 2 showed median values of TSH, fT3, and fT4 that were not significantly different. No clinical or electrocardiographic signs of heart disease were found. There were no significant differences in the developmental quotient between group 1 and group 2 patients with severe and moderate/mild CH.

CONCLUSIONS

Our data seem to indicate that there is not complete bioequivalence between drops and tablets, especially in infants with severe CH.

Competing wave-breaking mechanisms in quadratic media

We show that second-harmonic generation in the regime of weak dispersion/diffraction can exhibit a coexistence of wave breaking mechanisms, such that a gradient catastrophe yielding a dispersive shock wave competes with modulational instability, leading to the generation of wavetrains with incommensurate frequencies and eventually to the destruction of the shock wave-train.

Autoimmune-polyendocrinopathy-candidiasis-ectodermal-dystrophy in Calabria: clinical, immunological and genetic patterns

Autoimmune polyendocrinopathy-candidiasis-ectodermal- dystrophy (APECED), also known as autoimmune polyendocrine syndrome type 1 (APS-1), is a very rare disease. Diagnosis requires the presence of at least two of three major clinical features: chronic mucocutaneous candidiasis, chronic hypoparathyroidism, and Addison's disease.

DESIGN

In this study, we analyzed Autoimmune Regulator (AIRE) gene mutations and genotype-phenotype correlation in APECED patients originating from Calabria, a region in the south of Italy.

PATIENTS AND METHODS

Four patients and their first-degree relatives were evaluated for clinical manifestations, autoantibody presence and AIRE gene mutations.

RESULTS

Three patients carried a homozygous W78R mutation on exon 2, typical of patients with APECED from Apulia; the fourth patient had a homozygous R203X mutation on exon 5, typical of APECED patients from Sicily. Clinical disease expression showed wide variability. Analysis of relatives allowed the identification of 6 heterozygotes, none of whom showed major findings of APECED.

CONCLUSIONS

No AIRE gene mutations specific to Calabria were found in patients with APS-1, but mutations similar to those in patients from Apulia and Sicily. Heterozygosity for AIRE gene mutation is not associated with major findings of APECED.

Dispersive shock waves in phase-mismatched second-harmonic generation

We investigate wave-breaking and dispersive shock wave formation driven by a pulse undergoing second-harmonic generation in a quadratic medium. We show that the process is accessible in the regime of high phase-mismatch (cascading limit) and weak dispersion. Insight into the phenomenon is obtained by means of a suitable hydrodynamic reduction of the equations that govern the mixing.

Focal nodular hyperplasia of the liver after intensive treatment for pediatric cancer: is hematopoietic stem cell transplantation a risk factor?

Focal nodular hyperplasia (FNH) is a benign hepatic lesion very rarely described in the pediatric population. It has been reported more frequently in patients treated for pediatric cancers with chemotherapy or hematopoietic stem cell transplantation. The use of high dosage of alkylating agents, the occurrence of venous occlusive disease, graft-versus-host disease, and other variables linked to the hematopoietic stem cell transplantation procedure can represent risk factors for the development of FNH in the pediatric age. The discovery of hepatic nodules in the follow-up of patients treated for malignancies suggests recurrence of disease and raises a diagnostic dilemma. Here we describe possible risk factors, clinical and radiological findings of eight pediatric patients who developed focal nodular hyperplasia after hematopoietic stem cell transplantation. The aim of this report is to provide useful diagnostic tools to facilitate accurate diagnosis of FNH and suggest a correct management of this benign lesion during postcancer follow-up.