ECE2008 Poster Presentations Paediatric endocrinology (26 abstracts)
Endokrinologikum Hamburg, Hamburg, Germany.
Introduction: Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive diseases with increased adrenal androgens secretion from the adrenal cortex, characterized by simple virilizing and salt wasting forms. Deficiency of 21-hydroxylase, caused by mutations in the 21-hydroxylase gene (CYP21A2) is the most frequent CAH, accounting for more than 90 percent of CAH cases. Deficiency of 3 beta-Hydroxysteroid-Dehydrogenase Type II is caused by mutations in the HSD3B2 gene and accounts for about 110 percent of cases of CAH.
Patient: This report is about a 2-year-old patient of Turkish origin referred to our center with clinical finding of penoscrotal hypospadias and micropenis (stretched penile length 1.5 cm). Testicles were palpable bilaterally in the scrotum. Due to initial biochemical and hormonal findings moleculargentic analysis of CYP21A2 gene was already done, showing heterozygous germline mutations p.Val281Leu, p.Leu307fs, p.Gln318Stop and p.Arg356Trp. His parents are cousin-german to each other.
Methods: Genomic DNA was extracted from peripheral blood leukocytes. Coding regions and corresponding exon-intron boundaries of the CYP21A2 gene and the HSD3B2 gene were amplified by PCR and subjected to direct sequencing.
Results: A compound heterozygous state of these mutations was excluded by sequencing analysis of CYP21A2 genes of both parents (father has no mutation). Further hormonal studies suggested a 3 β-Hydroxysteroid dehydrogenase type II deficiency and justified sequence analysis of the HSD3B2 gene. A novel homozygous germline mutation (p.Trp355Arg) was found, for which both parents are heterozygous carriers.
Conclusion: To judge a case of CAH in the right way it is important to look at all clinical aspects in a differentiated way. Comprehensive (clinical, biochemical, hormonal) analysis should be conducted and approved by moleculargenetic analysis in line with a genetic counseling.