DESCRIPTION OF HYPERTRICHOSIS
Hypertrichosis is an increase of hair density in non androgen-dependent areas (limbs, back). Most of the time, this condition runs in the family affecting, particularly, dark-skinned women. “Idiopathic” hypertrichosis can occur in any racial group but it is more common in Asiatics. Terminal hairs on the forehead and eyebrows are thicker than usual. This can be an isolated symptom in a normal child or part of a series of syndromes.
Hypertrichosis can appear in association with congenital melanocytic nevus. Hairs become thicker and longer with age and nodules may develop alongside the lesion. These skin spots can be long and extremely disfiguring and may carry the risk of becoming malignant melanomas. Their surgical removal is advisable for cosmetic and preventive reasons, though it takes a series of stages.
Hypertrichosis also occurs in Becker’s nevus. This nevus is unilaterally acquired and segmented, and is usually found in the upper part of the back and shoulders of young men. The gradual increase of pigmentation begins in childhood and during puberty thick hairs are formed due to excessive androgenic activity in the affected area. There can be a single lesion or several lesions.
Localized growth of hair is not unusual on the surface of the arms (hypertrichosis cubiti or hairy elbow syndrome) in children and adults. In these cases it is important to perform a thorough neurological and radiological analysis.
Another very rare form of hypertrichosis is “acquired lanuginous hypertrichosis” occurring in adults who grow lanugo in the face area. It is usually associated with an internal disease.
Hypertrichosis may be due to the consumption of pharmaceutical drugs. Minoxidil, a drug prescribed for hypertension, when taken per mouth for a few weeks, can increase hair growth, including facial hair. Hair is lost 2 or 3 months after stopping treatment. Topical minoxidil has a similar yet more limited effect. It is only used to increase the amount of hair, which lasts as long as the treatment continues. Cyclosporine, which is used as an immunodepressant agent, can cause increased hair growth in transplanted hair. Some of the systemic diseases that can lead to acquired hypertrichosis are: porphyria, anorexia nervosa, malnutrition, dermatomyositis, hypothyroidism, pretibial myxedema and acrodynia.