Congenital lipoid adrenal hyperplasia (CLAH) is the most severe form of congenital adrenal hyperplasia which is caused by mutations in the steroidogenic acute regulatory protein (StAR). The mutations in StAR gene resulted in failure of the transport cholesterol into mitochondria for steroidogenesis in the adrenal gland. Twin sisters (A, B) with normal 46, XX were born at 36+2 gestational week, premature to nonrelated parents. They had symptoms as hyperpigmentation, slightly elevated potassium level and low level of sodium. Laboratory finding revealed normal 17-hydroxyprogesterone level, elevated adrenocorticotropin hormone (A, 4,379.2 pg/mL; B, 11,616.1 pg/mL), and high plasma renin activity (A, 49.02 ng/mL/hr; B, 52.7 ng mL/hr). However, the level of plasma cortisol before treatment was low (1.5 µg/dL) in patient B but normal (8.71 µg/dL) in patient A. Among them, only patient A was presented with adrenal insufficiency symptoms which was suggestive of CLAH and prompted us to order a gene analysis in both twin. The results of gene analysis of StAR in twin revealed same heterozygous conditions for c.544C>T (Arg182Cys) in exon 5 and c.722C>T (Gln258(*)) in exon 7. We report the first case on the mutation of p.R182C in exon 5 of the StAR gene in Korea.
Keywords: Lipoid congenital adrenal hyperplasia; Steroidogenic acute regulatory protein; Twins.