Corticosterone methyloxydase deficiency type II in a Croatian girl.

This is a brief case report on a four-month-old girl who was admitted for failure to thrive and moderate dehydration. On admission she was mildly dehydrated and undernourished but with otherwise normal physical findings. Laboratory investigation disclosed mild but constant hyponatremia and hyperkalemia, very high plasma renin activity (greater than 900 ng/mL per hour) and low plasma aldosterone concentration (2.