Doctor studies 'maturational hyperpigmentation'

January 1, 2006

Baltimore — A. Melvin Alexander, M.D., sees black adult patients with a mysterious hyperpigmentation, usually around their cheek areas, in his practice three or four times a week. But these patients rarely, if ever, seek treatment for hyperpigmentation; rather, Dr. Alexander notices it as he treats them for other conditions.

Baltimore - A. Melvin Alexander, M.D., sees black adult patients with a mysterious hyperpigmentation, usually around their cheek areas, in his practice three or four times a week. But these patients rarely, if ever, seek treatment for hyperpigmentation; rather, Dr. Alexander notices it as he treats them for other conditions.

The prevalence of the disorder piqued his interest - especially when he noticed that his brother, an otolaryngologist, had developed it, too. Dr. Alexander noted that his brother developed the condition as an adult, after gaining weight over a three- to four-year period.

Dr. Alexander reached into his own pocket to pay for a study on what he now calls "maturational hyperpigmentation." He says it is a type of hyperpigmentation that occurs principally on the malar and zygomatic facial areas. It is sometimes bilateral, sometimes unilateral.

Small study

Dr. Alexander advertised the study in his office, garnering the participation of six female and two male patients (including his brother). The patients ranged in age from 26 to 66 years of age, and all were black.

His goal was to call attention to the fact that this condition exists, and to look into possible causative factors.

"It is not in any dermatologic literature. It is not in the textbooks," he says. "This needs to be recognized, identified, named and studied."

Study participants filled out a 25-question questionnaire. Analyzing the results, Dr. Alexander and his co-author and wife, Janet Sloane, D.C., found:

"One of my wife's hypotheses was that this was related to the side that the person slept on, and that pressure was contributing to the condition, much like people's elbows often get dark if they have jobs where they sit at a desk a lot," Dr. Alexander says. "We found that 75 percent of participants said it was more prominent on the side they slept on the most."

Ultraviolet exposure appears to have minimal, if any, etiologic impact, according to Dr. Alexander.

Biopsy results

Dr. Alexander biopsied three of the participants. Toru Shoji, M.D., a Stratford, Conn., dermatopathologist, provided the reports.

"We found minimal inflammation in the dermis, and the biopsies were virtually identical, and all showed substantially increased pigmentation in the basal cell layer, as well as the squamous layer," he says. "There also were increased melanocytes in the basal layer."

A number of hyperpigmented disorders show increased pigmentation at the basal cell layer or in the squamous layer but do not show increased melanocytes. Increased melanocytes is indicative of melanocyte proliferation, according to Dr. Alexander.

"In a typical biopsy you would see melanocytes about every six to eight cells on the basal layer; here we were seeing them every three to four cells in the basal layer," he says.