ALOPECIA AREATA AND HYPERTRICHOSIS: A CASE REPORT ALOPECIA AREATA E IPERTRICOSI: CASO CLINICO

Hypertrichosis is an abnormal hair growth for age, sex, race or for a particular body area of an individual. For this special clinical condition a differential diagnosis is proposed with hirsutism: male-pattern hair growth in a female or child. It tipically involves the upper lip, chin, cheeks, breast areola, linea alba and the top of the pubic triangle and it is, usually, due to an androgen excess. The most common cause in female is the polycystic ovary syndrome but other causes, in both sexes, include hyperandrogenic insulin resistance acanthosis nigricans syndrome, androgen-secreting tumors, and androgen drug intake. When in women it is accompanied to other masculinization signs it is usually definied virilization. This clinical condition is associated with a more complete voice change, changes in libido, and clitoromegaly . Two different mechanisms are proposed to explain hypertrichosis’s development: conversion of vellus to terminal hairs and changes in the hair-growth cycle. Hair cycle is characterized by the switch from a period of very rapid growth, pigmentation, and hair-shaft production (anagen, the active-growth phase, with classification ranging from stages I to VI) to a short, apoptosis-driven phase of organ involution (catagen). After catagen, the hair follicle enters a period of relative quiescence (telogen) before it reenters anagen. This regene rative cycle is made possible by an abundance of keratinocyte and melanocyte stem cells located for the most part in the so-called bulge area. Alopecia areata is a