Sonographic Examination of the Adrenals of Neonates with Congenital Adrenal Hyperplasia

Overview

Congenital adrenal hyperplasia (CAH) is a group of autosomal-recessively transmitted diseases the basis ofwhich is an enzymatic block during the formation of glucocorticoids and, depending on the affection of the enzyme,also mineral corticoids. Another consequence of the defect is as a rule increased production of androgen activehormones. An inadequate cortisol level raises via a feedback the secretion of pituitary ACTH with subsequenthypertrophy of the adrenal cortex. Hyperpigmentation of the skin and genital in both sexes and masculinizationof the female genital arouse clinical suspicion of CAH immediately after delivery. In the most serious cases theneonate develops symptoms of so-called salt crisis which leads to a collapse of the circulation.The basic diagnostic criterion in CAH is assessment of an elevated level of the hormonal precursor before theenzymatic block. The results of the examination are however available after an interval of several days. The startof adequate therapy thus at first depends on the correct interpretation of clinical data and results of complementaryexaminations incl. ultrasound imaging of the adrenals.The sonographic picture of the adrenal affected with CAH need not be manifested only by enlargement of theorgan but also by quite specific signs - lobulization of the surface and a changed echostructure. Based on threecase-histories the authors evaluate the importance of sonographic examination of the adrenals in neonates withsuspected CAH and present a review of the literature.

Key words:
congenital adrenal hyperplasia, CAH, adrenals, sonography, neonate