Growth Hormone-Responsive Alopecia

Condition Overview

This is a rare cause of bilateral symmetrical hair loss. Growth hormone (somatotropin) is secreted by the pituitary gland. This disease has been observed in Pomeranians, Chow Chows, Poodles, Samoyeds, Keeshounds, and American Water Spaniels. It occurs predominantly in male dogs.

Symptoms

Symptoms generally appear at puberty, but may occur at any age.

All symptoms +

Causes

In some cases, for unknown reasons, the pituitary does not manufacture or release adequate concentrations of growth hormone, resulting in coat and skin changes similar to those described for hyperestrogenism.

Diagnosis

Skin and coat changes begin in the perineum around the genital areas and proceed to the underside of the abdomen. Typically, the hair becomes dry and brittle, falls out easily, and fails to regrow. Later the skin becomes darkly pigmented. A dry, flaky seborrhea (dandruff) often develops, particularly in females. The coat and skin changes follow a symmetrical pattern.

Treatment

It is important to exclude other hormone-dependent causes of hair loss. The treatment of choice for growth hormone-responsive alopecia is neutering. If the coat does not improve, the dog may respond to growth hormone administered subcutaneously 3 times a week for 4 - 6 weeks. Dogs receiving growth hormone must be monitored for the development of diabetes mellitus.

Prevention

There is no known prevention for this condition.

Support

Please contact your veterinarian if you think your pet may have this condition.