[Clinical and StAR genetic characteristics of 33 children with congenital lipoid adrenal hyperplasia].

Objective: To analyze the clinical and genetic characteristics of 33 children with congenital lipoid adrenal hyperplasia (CLAH) caused by StAR gene defects. Methods: The clinical, biochemical, genetic, and follow-up (until December 2021) data of 33 children diagnosed with CLAH from 2006 to 2021 were retrospectively analyzed in Xinhua Hospital, Shanghai Jiao Tong University School of Medicine. Results: Of the 33 children with CLAH, 17 had a karyotype of 46, XX and 16 had a karyotype of 46, XY; 31 were female and 2 were male by social gender. Classic type and non-classic type were found in 30 and 3 children respectively. The age at diagnosis was 9.0 (3.0, 34.5) months. All the 30 cases with classic CLAH presented within the first year of life with skin hyperpigmentation (28 cases, 93%), vomiting and(or) diarrhea (19 cases, 63%), no increase in body weight (8 cases, 27%), elevated adrenocorticotropic hormone levels (21cases (70%)>275 pmol/L), decreased cortisol levels (47 (31,126) nmol/L), hyponatremia ((126±13) mmol/L), hyperkalemia ((5.7±1.1) mmol/L), and normal 17α-hydroxyprogesterone levels (30 cases, 100%). All these with classic CLAH exhibited female external genitalia. Three children with non-classic CLAH (including 2 cases of 46, XY and 1 case of 46, XX) also showed signs and symptoms of adrenal insufficiency, but 2 of them had an age of onset later than 1 year of age, including 1 case of 46, XY with male external genitalia and 1 case of 46, XX with female external genitalia. The other 46, XY patient with non-classic CLAH presented with adrenal insufficiency at 2 months of age, showing micropenis and hypospadias. In the 17 females with 46, XX, 4 older than 10 years of age showed spontaneous pubertal development. A total of 25 StAR gene pathogenic variants were identified in 33 patients, with p.Q258* (18/66, 27%), p.K236Tfs*47 (8/66, 12%) and p.Q77* (6/66, 9%) being the common variantion. Six novel variants were found, including c.358T>G, c.713_714del, c.125del, c.745-1G>A, c.179-2A>C, and exon 1 deletion. Conclusions: Patients with classic CLAH typically present with signs and symptoms of primary adrenal insufficiency in the early infancy period and female external genitalia. p.Q258*, p.K236Tfs*47 and p.Q77* are common variants in CLAH patients.

[Analysis of six children with 3-methylglutaconic aciduria].

Objective: To explore the clinical characteristics, genotypes and long-term outcomes of individuals with 3-methylglutaconic aciduria. Methods: The clinical features, biochemical data, genetic test results and treatment outcomes of six children with 3-methylglutaconic aciduria admitted to the Department of Endocrinology, Genetics and Metabolism, Xinhua Hospital from February 2017 to February 2019 were retrospectively analyzed and the Gesell developmental diagnosis schedule was performed to evaluate the development of four patients. Results: Among 6 children with 3-methylglutaconic aciduria 2 were males and 4 were females.Four cases had 3-methylglutaconic aciduria type Ⅰ and 2 cases had 3-methylglutaconic aciduria with deafness,encephalopathy, and Leigh-like syndrome. Five of 6 patients were detected by newborn screening among whom 4 remained asymptomatic, and only one had a postmortem diagnosis. Among them, 4 patients remained asymptomatic, while two presented with clinical symptoms such as jaundice and dyspnea and the age of disease onset was 1 and 2 days respectively. The concentration of 3-methylglutaconic acid in urine of all affected individuals was between 22.38 and 77.09 mmol/molCr, which was above the normal value. Genetic tests were performed for all patients. Eleven variants were identified in 2 genes, of which 10 variants were novel and only c.442C>T p.(R148X) has been previously reported; Seven variants (c.656-2delA, EX5-EX6 Del, c.942+3A>G, c.373C>T p.(R125W), c.895-3C>G, c.667C>T p.(R223X) and c.894+5G>A) were in AUH gene. The others (c.548G>A p.(R138Q), c.442C>T p.(R148X), c.1339C>T p.(R447X) and c.973dupA p.(M325Nfs*5) were in SERAC1 gene. After being treated with leucine diet restriction and L-carnitine, 4 patients with AUH gene variation who were from asymptomatic phase developed normally, whereas those 2 patients with SERAC1 gene variation had a poor prognosis. During the follow-up, 2 patients exhibited varying degrees of psychomotor retardation, the rest had normal course of development. Conclusions: There are significant clinical heterogeneities among individuals with 3-methylglutaconic aciduria. The most common pathogenic variants are splicing variations, followed by nonsense, missense and frameshift mutations. Leucine-free diet and oral L-carnitine therapy are effective for some patients. Newborn screening is essential for early diagnosis and improvement of prognosis.

[Analysis of phenotypes and genotypes in 66 patients with 21-hydroxylase deficiency identified by neonatal screening].

OBJECTIVE: To analyze the phenotype-genotype correlation of 21-hydroxylase deficiency (21-OHD) patients found by neonatal screening, and to investigate the characteristics of gene frequency of these patients. METHOD: Clinical and biochemical data of 66 21-OHD patients diagnosed by neonatal screening in department of pediatric endocrinology and genetics and neonatal screening center of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from 2009 to 2014 were retrospectively analyzed. Point mutations of CYP21A2 gene were analyzed by Sanger sequencing, and large gene deletions were detected by multiplex ligation-dependent probe amplification (MLPA). Then the correlation between phenotypes and genotypes of these patients were analyzed. RESULT: (1) Forty-one out of 66 patients who presented adrenal crisis or other signs of salt loss at age range from 4 days to 2 months were classified as salt-wasting forms. The remaining 25 patients did not present any signs of salt loss at preliminary diagnosis (12 days-2 months). (2) Definite mutations of CYP21A2 gene on two alleles were found in all 66 patients (132 alleles). A total of thirteen types of different point mutations (98/132, 74.2%), large gene deletions (24/132, 18.2%) and clusters of point mutations (10/132, 7.6%) were found. The most frequent point mutations were I2G, p. I173N, p. R357W, p. G111Vfs*21 and p. Q319*, accounting for 65.2% of alleles. (3) Phenotype and genotype correlation analysis was performed in 41 21-OHD patients with salt wasting forms. Predicted phenotypes according to genotypes in 36 (87.8%) of the 41 patients were consistent with their actual phenotypes. In 4 out of the 41 patients, the actual phenotypes were different from predicted phenotypes according to their genotypes. And in one patient, prediction of phenotype could not be made based on genotype as carrying an unknown function mutation on one allele. CONCLUSION: Adrenal crisis or other signs of salt loss were found in 62% of 21-OHD patients at age range from 4 days to 2 months. In 66 Chinese 21-OHD children, total mutation frequency of I2G, p. I173N, p. R357W, p. G111Vfs*21 and p. Q319* accounted for 65.2% of alleles. In 87.8% of patients with salt wasting forms, predicted phenotypes according to genotypes were consistent with their actual phenotypes.

[Applying multiplex ligation-dependent probe amplification in the diagnosis of 5 cases with ornithine transcarbamylase deficiency].

OBJECTIVE: To detect large genomic deletions or duplications of ornithine transcarbamylase (OTC) gene by multiplex ligation-dependent probe amplification (MLPA). METHOD: Thirty cases of suspected OTC deficiency (OTCD) patients based on tandem-mass spectrum results were recruited in Xinhua Hospital from 2012 to 2014, among whom 13 were male and 17 were female. Sanger sequencing of OTC gene revealed mutations in 23 cases. MLPA was performed in the patients whose previous Sanger sequencing failed to detect any disease-causing mutation. The samples were treated via the steps of DNA degeneration, the probe hybridization, connecting the hybridization probe, PCR amplification and capillary electrophoresis. The data were analyzed using Coffalyser software. RESULT: Abnormal MLPA results were found in 5 patients without mutation detected in previous Sanger sequencing. Patient 1, a 9-year old girl, had a heterozygous deletion of Exon 2-4. Patient 2, a male newborn, died 10 days after birth. The examination of the mother's sample by MLPA revealed a heterozygous duplication of exon 2-6. Patient 3, a 10-day old boy, was found to harbor a hemizygous deletion of exon 7-10. Patient 4, a 2-year old girl, harbored a heterozygous deletion of exon 1-4. The fifth patient died at the age of 6 years, and his mother carried a heterozygous duplication of exon 1-4. CONCLUSION: MLPA can be helpful in detecting the OTC gene defects, particularly for OTCD patients without mutation detected by Sanger sequencing.