Familial hypogonadotropic hypogonadism with alopecia.

In one family several male and female members had hypogonadism and frontoparietal alopecia, whereas other members with normal sexual development had normal scalp hair. Clinical and laboratory evaluation of three affected young men (two brothers and their cousin) revealed that the hypogonadism was the result of decreased serum concentrations of follicle stimulating and luteinizing hormones. There was no evidence of a deficiency of any other pituitary hormone. Long-term treatment of the three patients with human chorionic gonadotropin resulted in an increase in the serum testosterone concentration, the appearance of male secondary sex characteristics and an increase in the size of the external genitalia.