Hipomelanosis macular progresiva: respuesta al tratamiento con minociclina / Progressive macular hypomelanosis: response to treatment with minocycline

La hipomelanosis macular progresiva (HMP) es una dermatosis caracterizada por máculas hipopigmentadas, que se observa con mayor frecuencia en las mujeres y en los fototipos III y IV. Se ha asociado a Cutibacterium acnes (C. acnes) de tipo III como factor etiológico. Se presenta el caso de una paciente de 30 años, con máculas hipopigmentadas redondeadas en el tronco y la raíz de los miembros inferiores, de 10 años de evolución. El estudio histológico informó disminución del número de melanocitos y de pigmento melánico en la capa basal e infiltrado inflamatorio mononuclear perivascular superficial. Se indicó minociclina 100 mg/día por vía oral durante 8 meses, tras lo cual se observó la resolución total de las lesiones.

Progressive macular hypomelanosis (PMH) is a dermatosis characterized by hypopigmented macules, most frequently found in females and in phototypes III and IV. Cutibacterium acnes (C. acnes) type III has been associated as an etiological factor. We present the case of a thirty-year-old female patient with a 10-year history of nummular hypopigmented macules located on the top of the lower limbs and on the trunk. The histological study reported a decrease in the number of melanocytes and melanotic pigment in the basal layer and the presence of superficial perivascular mononuclear inflammatory infiltrate. After an 8-month regimen of oral minocycline 100 mg/day, there was a complete resolution of the lesions.

Efficacy and relapse rates of different treatment modalities for progressive macular hypomelanosis.

Background: Progressive macular hypomelanosis is an acquired disorder characterized by hypopigmented macules mostly on the trunk and upper extremities. Although many treatment modalities have been proposed for this condition with variable success rates, there are few reports comparing their efficacy and relapse rates. Aim: To compare the efficacy and relapse rates of different treatment modalities for progressive macular hypomelanosis. Methods: Case records of patients diagnosed with progressive macular hypomelanosis and treated in National Skin Centre for a six year period between 2008 and 2014 were reviewed. Patient demographics, distribution of hypopigmented macules, treatment efficacy and relapse rates were noted. Results: A total of 108 patients were seen for progressive macular hypomelanosis over the study period; of these, 40 opted for no treatment but were followed up. Thirty‑six were treated with topical antimicrobials and 32 with phototherapy. Of those untreated, 23% recovered spontaneously while 38% in the antimicrobial group and 90% in the phototherapy had remission of their hypopigmentation. After 2 years of follow‑up, relapse occurred only in the phototherapy group. Limitations: The main limitation is the retrospective design whereby diagnosis is dependent on the attending dermatologist. Conclusions: Narrow‑band ultraviolet B therapy appears to be the most effective treatment for progressive macular hypomelanosis but also has the highest potential for relapse. Response rates for antimicrobial therapy are lower and slower, but patients who responded did not relapse. A combination of topical/systemic antimicrobials with narrow‑band ultraviolet B therapy might be the best option to hasten recovery and minimize relapse.

Clinicopathologic Features of Progressive Macular Hypomelanosis in Korea / 대한피부과학회지

BACKGROUND: Progressive macular hypomelanosis, a disease of uncertain etiology, was first described by Guillet et al. in 1988. It is characterized by asymptomatic hypopigmented macules and patches that appear on the trunk and upper extremities. It is a relatively recently described disorder and more case reports are needed. OBJECTIVE: The purpose of the study was to document the clinicopathologic and ultrastructural features of progressive macular hypomelanosis in Korean patients. METHODS: Patients who presented to our hospital and were diagnosed with progressive macular hypomelanosis from July 2009 to June 2014 were enrolled in this study. Skin scrapings were taken for fungal tests, and skin biopsy specimens from lesional and normal skin were obtained. Sections of the skin biopsies were stained with hematoxylin and eosin, Brown and Brenn Gram stain, and Fontana-Masson stain, and they were incubated with a panel of immunohistochemical reagents used to identify melanocytes, namely, gp-100, melan-A, and microphthalmia-associated transcription factor. The tissues from two patients were also examined using electron microscopy. RESULTS: Over the course of 5 years, 16 patients presented with ill-defined hypopigmented macules on their trunks and upper extremities. The mean age of the patients was 28.4+/-9.0 years and the male to female ratio was about 1 : 4. Histopathologically, lesional skin showed a reduced level of pigmentation, while the number of melanocytes was preserved. None of the patients showed bacterial colonization of the pilosebaceous units. Electron microscopy demonstrated smaller and less melanized melanosomes in the lesional keratinocytes. CONCLUSION: Progressive macular hypomelanosis is a hypopigmentary disorder that is characterized by a loss of melanosomes without damage to the melanocytes. Although there are several reports that describe a possible relationship between Propionibacterium acnes and progressive macular hypomelanosis, it remains unclear.

Clinical and experimental studies on progressive macular hypomelanosis / 中华皮肤科杂志

Objective To assess the clinical features and diagnostic index of progressive macular hypomelanosis(PMH).Methods Eight patients with PMH were recruited into this study.Wood's lamp and in vivo confocal laser scanning microscopy(CLSM)were utilized to observe the lesions of all patients.Microbiological culture of lesion specimens from 2 patients was performed.Tissue specimens from 4 patients underwent immunohistochemieal staining with anti-S-100 and anti-TRP-1 antibodies for the detection of melanocyte quantity.Electron microscopy wag utilized to observe ultrastructural features of lesions.Primary culture of melanocytes was carried out with lesional epidermis.Resnits Under Wood's lamp.the lesions of PMH showed punctiform red fluorescence.CLSM revealed complete pigmented tings in lesions with decreased melanin granules compamd with those surrounding normal skin.Microbiological culture grew red fluorescence-producing,gram-positive bacillus which was identified as Propionibacterium acnes.Immunohistochemistry showed no significant difference in the number of S-100-postive cells or TRP-1-positive cells per high power field (× 400)between lesions and surrounding normal skin (8.25±0.96 vs 8.75±1.71,4.25±0.96 vs 4.50±1.29,both P>0.05).Ultrastructural studies showed a large reduction in the number of type Ⅳ melanosomes in lesions of PMH,along with numemus membrane bound bodies and clusteredly distributed,small type Ⅱ-Ⅳ melanosomes.Melanocytes,with morphological similarity to normal melanocytes,were successfully isolated from the lesional tissue,cuhured and identified.Conclusion A primary diagnostic criteria is pro-posed for PMH according to the clinical and experimental studies.

Progressive Macular Hypomelanosis in Korean Patients: A Clinicopathologic Study

BACKGROUND: Progressive macular hypomelanosis is characterized by ill-defined, non-scaly, hypopigmented macules primarily on the trunk of the body. Although numerous cases of progressive macular hypomelanosis have been reported, there have been no clinicopathologic studies of progressive macular hypomelanosis in Korean patients. OBJECTIVE: In this study we examined the clinical characteristics, histologic findings, and treatment methods for progressive macular hypomelanosis in a Korean population. METHODS: Between 1996 and 2005, 20 patients presented to the Department of Dermatology at Busan Paik Hospital with acquired, non-scaly, confluent, hypopigmented macules on the trunk, and with no history of inflammation or infection. The medical records, clinical photographs, and pathologic findings for each patient were examined. RESULTS: The patients included 5 men and 15 women. The mean age of onset was 21.05+/-3.47 years. The back was the most common site of involvement. All KOH examinations were negative. A Wood's lamp examination showed hypopigmented lesions compared with the adjacent normal skin. A microscopic examination showed a reduction in the number of melanin granules in the lesions compared with the adjacent normal skin, although S-100 immunohistochemical staining did not reveal significant differences in the number of melanocytes. Among the 20 patients, 7 received topical drug therapy, 6 were treated with narrow-band ultraviolet B phototherapy, 4 received oral minocycline, and 3 did not receive any treatment. CONCLUSION: Most of the patients with progressive macular hypomelanosis had asymptomatic ill-defined, non- scaly, and symmetric hypopigmented macules, especially on the back and abdomen. Histologically, the number of melanocytes did not differ significantly between the hypopigmented macules and the normal perilesional skin. No effective treatment is known for progressive macular hypomelanosis; however, narrow-band ultraviolet B phototherapy may be a useful treatment modality.

A Case of Progressive Macular Hypomelanosis Treated with Narrow Band UVB / 대한피부과학회지

Progressive macular hypomelanosis is an idiopathic acquired hypopigmentary disorder first described in 1988. The disorder is characterized by ill-defined, non-scaly, round to oval, hypopigmented patches symmetrically localized on the trunk. No clinical symptoms have been observed. Currently, diagnosis is made on clinical grounds and any histological, laboratory investigations are not diagnostic. This disorder does not respond to conventional treatment and its clinical course is variable. We experienced a case of progressive macular hypomelanosis that was successfully treated with narrow band UVB phototherapy.