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Progressive macular hypomelanosis among Egyptian patients: a clinicopathological study
Mohamed Khaled Selim1, El-Shahat Farag Ahmed1, Mamdouh Morsy Abdelgawad1
1Department of Dermatology, Andrology and STDs, Mansoura University, Egypt.
Background:
Progressive macular hypomelanosis (PMH) is a disease of unclear etiology. Propionbacterium acnes (P. acnes) was claimed to be an etiological factor.
Objectives:
The purpose of this study was to document the clinicopathological features of PMH in Egyptian patients and to evaluate the therapeutic outcome.
Methods:
Patients with clinical features of PMH were recruited. Wood's lamp examination, skin scrapings for fungi, and skin biopsy specimens were obtained. Biopsies were stained with hematoxylin and eosin, PAS, Fontana-Masson, and S100 protein. Patients received either narrow-band UVB (nbUVB) or nbUVB plus daily topical clindamycin 1% and benzoyl peroxide gel 5% (bcUVB). The period of active treatment was 14 weeks followed by a follow-up period of 24 weeks.
Results:
Twenty-nine patients were included. Microscopic evaluation of skin biopsy specimens showed no significant differences between lesional and normal skin. Fontana-Masson stained sections showed overall reduction of melanin granules in the basal layer of lesional skin only and S100 staining did not detect significant differences in the number of melanocytes in lesional and normal skin. Nearly complete repigmentation was reported in 10 patients treated with bcUVB compared to 9 patients treated with nbUVb with no significant differences between both groups after 14 weeks. Only 2 patients in each group retained the pigmentation and the remaining patients returned to the baseline color before treatment.
Conclusions:
This study documented the clinicopathological features of PMH among Egyptians. No permanently effective treatment is available. Further studies are needed to prove or disprove the pathogenic role of P. acnes in PMH.
Insights
This study investigated progressive macular hypomelanosis (PMH) in Egyptian patients, finding no permanently effective treatment. Further research is needed to confirm the role of Propionibacterium acnes in PMH.
Area of Science:
- Dermatology
- Pathology
- Microbiology
Background:
- Progressive macular hypomelanosis (PMH) is a skin condition with an unknown cause.
- Propionibacterium acnes (P. acnes) has been suggested as a potential etiological factor.
Purpose of the Study:
- To describe the clinicopathological characteristics of PMH in Egyptian patients.
- To assess the effectiveness of different treatment regimens for PMH.
Main Methods:
- 29 patients with PMH underwent Wood's lamp examination, skin scrapings, and skin biopsies.
- Biopsies were analyzed using H&E, PAS, Fontana-Masson, and S100 staining.
- Treatments included narrow-band UVB (nbUVB) alone or with topical clindamycin and benzoyl peroxide (bcUVB).
Main Results:
- Skin biopsies showed no significant microscopic differences between lesional and normal skin.
- Fontana-Masson staining indicated reduced melanin in lesional skin's basal layer; S100 staining revealed no difference in melanocyte count.
- Both nbUVB and bcUVB treatments showed similar repigmentation rates, with most patients relapsing after treatment cessation.
Conclusions:
- The study characterized PMH in Egyptians, highlighting a lack of lasting treatment options.
- The pathogenic role of P. acnes in PMH requires further investigation.
- No definitive treatment for progressive macular hypomelanosis was identified in this study.
