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51. How to monitor a child with CAH due to 21α-hydroxylase defi ciency?

The clinical parameters to be monitored in a child with CAH include growth

velocity, weight, regression/progression of features of virilization (clitoromeg-

aly, pubic hair, and acne), blood pressure, and stigma of glucocorticoid excess

at three monthly intervals. In addition, bone age should be assessed annually

after 2 years of age. Growth velocity is a sensitive parameter for assessment of

adequacy of therapy as decreased growth velocity suggests overtreatment,

while increased growth velocity suggests undertreatment. Biochemical moni-

toring includes serum 17(OH)P, androstenedione, testosterone, plasma renin

activity (PRA), and serum potassium and sodium. Sample for biochemical

evaluation should be taken in the morning between 0800 and 0900h without

discontinuing the morning dose of hydrocortisone. Serum 17(OH)P should be

targeted between 4 and 12 ng/ml as an attempt to normalize serum 17(OH)P

results in overtreatment with glucocorticoids. Androstenedione and testoster-

one should be maintained in age- and gender-specifi c normal range. PRA and

potassium should be monitored as the requirement of fl udrocortisone decreases

with advancing age, and the levels are to be maintained within the reference

range.

Subclinical aldosterone deficiency

Na+ and extracellular volume depletion

RAAS activation ↑ADH

↑PRA ↑ACTH

↑AT II

↑CRH Adrenal cortical

proliferation

↑ADH

↑ACTH

Fig. 10.13 Consequences of subclinical aldosterone defi ciency in a child with simple virilizing
CAH

10 Congenital Adrenal Hyperplasia