Randomized, double-blind study of minocycline vs. placebo in the treatment of progressive macular hypomelanosis

Introduction: Progressive macular hypomelanosis is a common skin hypopigmentation found in all ethnicities, yet it is seldom diagnosed. It affects young adults, especially women, and is often mistaken with pityriasis alba and pityriasis versicolor. It is character- ized by symmetric, well-defined, non-desquamative nummular hypopigmented macules in body areas with a greater concentration of sebaceous glands (trunk, thorax, abdomen and lumbar regions). Its etiology is poorly understood, and there is no effective treatment. A red fluorescence has recently been discovered in the lesion, suggesting the presence of porphyrin, produced by Propionibacterium acnes.
Objective: To compare the efficacy of 100 mg/day minocycline vs. placebo in the treat- ment of progressive macular hypomelanosis.
Methods: Patients over 18 (n = 20), who had suffered from the condition for more than 3 months (without treatment in the previous 3 months), who did not have an allergy to tetracycline, were randomized to receive minocycline or placebo. Wood''''''''s Lamp examina- tions and clinical evaluations (with descriptions and classifications using a color scale), and standardized picture records were conducted at baseline and 30 and 90 days after treatment.
Results: Eighteen patients completed the study. The group treated with minocycline pre- sented a statistically significant improvement (p < 0.05) compared to the control group.,br> Conclusion: 100 mg/day minocycline for 30 days was effective in treating progressive macular hypomelanosis, meaning that Propionibacterium acnes probably has a role in the condition''''''''s pathogeny.

Keywords: MINOCYCLINE, HYPOPIGMENTATION, PLACEBO EFFECT, TREATMENT