Microphallus: clinical and endocrinological characteristics.

The clinical and endocrinological features of 15 male subjects with small but normally formed external genitalia are reviewed. Nine of these patients had a simple microphallus alone, while the other 6 patients exhibited associated central nervous system defects. The endocrine data obtained from both groups were the same and were consistent with defective hypothalamic function. Parenteral testosterone seems to be the present treatment of choice but we believe it should be started early in life to take advantage of the greater hyperplastic response of the young.