Hirsutism: a review of the genetic and experimental aspects

Abstract

The management of a patient with hirsutism need not be complicated even though the associated disorders are numerous. Endocrinologic abnormalities are seen in about 1% of the women who consult a physician about hypertrichosis but are commoner in severe degrees of hirsutism. New techniques will probably identify additional cases of abnormal endocrine function, like those shown by Bardin and Mahoudeau in some virilized women, who had increased testosterone production rates but, paradoxically, normal plasma testosterone levels because of the increased clearance of hormone by extrahepatic tissues. However, explanations for the extraordinary variability normally found in man and for the numerous cases of hypertrichosis that arise from nonendocrinologic causes will probably come from additional investigations of the end organ responsiveness of the pilosebaceous structures themselves to androgenic stimulation. Studies in these areas have only just begun, but already tangible results can be seen in several reports all having to do with variations in the end organ responsiveness of pilosebaceous follicles in the skin. New avenues of investigation of hair biology have been opened by Freedberg, who reported a cell free amino acid incorporating system prepared from mammalian hair root cells that could provide important information about the regulatory mechanisms and biochemical pathways involved in the synthesis of hair protein. Already available is a more direct application of plucked hair bulbs for the diagnosis of genetic disorders and the identification of heterozygotes reported by Silvers and associates in the Lesch Nyhan syndrome. Little is known about environmental influences on hair growth, but the possibilities of Freedberg's model system as well as the use of follicle squash preparations for studies of cell kinetics and response to irradiation suggest that much additional information will be forthcoming shortly. It has previously been shown that protein deprivation causes significant atrophy of the hair root; such information has been used to survey protein malnutrition in a population group. The hair roots, therefore, are an important biologic tissue, easily available for investigation.