Vitiligo: characterization of melanocytes in repigmented skin after punch grafting.

BACKGROUND: Punch grafting is a surgical technique mainly applied in therapy-resistant, stable and circumscribed vitiligo. OBJECTIVE: (i) To characterize in detail the features of the repigmented skin among punch grafts; and (ii) to correlate the ex vivo results with clinical data and punch grafting outcome. METHODS: We evaluated by immunohistochemistry and image analysis the expression of a panel of specific melanocyte markers including HMB45, MITF, c-kit, MART-1 and TRP1, the proliferation marker Ki67 and the cell-cell adhesion molecule E-cadherin in tissue samples collected from nine patients after punch grafting. RESULTS: Cells positive for MITF, c-kit, MART-1 and TRP1 were detected in the repigmented skin of all biopsies, whereas no reactivity was observed for HMB45. Melanocytes were identified along the entire length of the sections, and their mature state was assessed by the immuno-reactivity for the differentiation marker MART-1, the absence of cells positively stained for Ki67 and by the co-expression of c-kit and TRP1, a marker of a differentiated and pigmented state. Clinically, smaller punch grafts aimed at repigmenting lesional areas on the face gave the faster clinical results with no side-effects. Patients subjected to bigger punch grafts on the knee exhibited a longer repigmentation time and presented cobble stoning. CONCLUSION: Our results suggest that the repigmentation observed in the areas between the grafts is due to the activation of the melanocytes located in the donor sites. These cells start to horizontally migrate towards the lesional skin thanks to successively the enlargement of intercellular spaces in relation to a decrease of E-cadherin reactivity and the up-modulation of pro-melanogenic mediators. Production and transfer of melanin in the surrounding keratinocytes and their persistence were assessed by the reactivity for MITF, c-kit, MART-1 and TRP1 but not for the pre-melanosome marker (HMB45).

Most individuals with either segmental or non-segmental vitiligo display evidence of bilateral cochlear dysfunction.

BACKGROUND: Vitiligo has been classified clinically into segmental vitiligo (SV) and nonsegmental vitiligo (NSV) and may also be associated with audiological abnormalities. OBJECTIVES: We examined cochlear function in ears of individuals with SV and NSV, including subjects with facial and nonfacial lesions, and in patients who have SV with unilateral facial involvement. METHODS: This study included 25 patients with SV and 28 patients with NSV. Fifteen age- and sex-matched healthy individuals served as controls. Cochlear function was studied using the distortion product otoacoustic emissions (DPOAEs). Data were analysed using SPSS. RESULTS: Sixty-four ears (60%) of patients with vitiligo had cochlear dysfunction while the control group exhibited no abnormalities. On comparing the cochlear dysfunction of patients with SV with patients with NSV, no statistically significant difference was found. The ears on both sides, affected and unaffected by vitiligo, in patients with SV showed cochlear dysfunction with no statistically significant difference in DPOAE. To determine the effect of the lesion side on cochlear function, we compared DPOAE amplitude using Student's t-test. The comparisons included NSV of the face vs. NSV on other areas, NSV of the face vs. SV of the face and SV of the face vs. SV of other areas. No statistically significant difference was found in these comparisons. CONCLUSIONS: Bilateral cochlear dysfunction is common in both NSV and SV and does not reflect the appearance of vitiligo in the skin. Our results underscore the important role of melanocytes and melanin in cochlear function, and suggest that the cochlear abnormalities in SV point to the presence of additional nonsegmental pathophysiological events underlying all forms of vitiligo.

Possible mechanisms by which topical 5-Fluorouracil and dermabrasion could induce pigment spread in vitiligo skin: an experimental study.

The combination of skin ablation and 5-Fluorouracil (5-FU) ointment was previously tried in the treatment of vitiligo, and good results were specifically reported in glabrous skin without follicular melanocyte reservoirs. Methods. This study was carried out on the skins of seven guinea pigs: three were treated with mechanical dermabrasion plus topical 5-FU in an achromic area contiguous to a pigmented area; two were treated by only dermabrasion in a similar area; and two were treated by topical 5-FU alone. Clinical, histological, and ultrastructural studies were performed over two months. Results. In guinea pigs treated with dermabrasion plus 5-FU, we observed firstly a delay of wound healing with an obvious inflammatory reaction, and, after two months, evident pigment spread from the pigmented into the achromic area. After six months, we noticed black hair regrowing in the achromic area. Pigment spread was not seen in the guinea pigs skin treated by either dermabrasion or topical 5-FU. We suggest that the inflammatory mediators and enzymes (metalloproteinases), which are locally released over a long time, could stimulate and facilitate melanocyte proliferation and migration through the enlarged intercellular spaces of the epidermis. This sequence of events may be applied to vitiligo patients treated with 5-FU on ablated lesions.

Revised classification/nomenclature of vitiligo and related issues: the Vitiligo Global Issues Consensus Conference.

During the 2011 International Pigment Cell Conference (IPCC), the Vitiligo European Taskforce (VETF) convened a consensus conference on issues of global importance for vitiligo clinical research. As suggested by an international panel of experts, the conference focused on four topics: classification and nomenclature; definition of stable disease; definition of Koebner's phenomenon (KP); and 'autoimmune vitiligo'. These topics were discussed in seven working groups representing different geographical regions. A consensus emerged that segmental vitiligo be classified separately from all other forms of vitiligo and that the term 'vitiligo' be used as an umbrella term for all non-segmental forms of vitiligo, including 'mixed vitiligo' in which segmental and non-segmental vitiligo are combined and which is considered a subgroup of vitiligo. Further, the conference recommends that disease stability be best assessed based on the stability of individual lesions rather than the overall stability of the disease as the latter is difficult to define precisely and reliably. The conference also endorsed the classification of KP for vitiligo as proposed by the VETF (history based, clinical observation based, or experimentally induced). Lastly, the conference agreed that 'autoimmune vitiligo' should not be used as a separate classification as published evidence indicates that the pathophysiology of all forms of vitiligo likely involves autoimmune or inflammatory mechanisms.

Skin pigmentation after NB-UVB and three analogues of prostaglandin F(2alpha) in guinea pigs: a comparative study.

BACKGROUND: Ultraviolet B (UVB) is a well-known modality in increasing skin pigmentation through a variety of proposed mechanisms. Prostaglandin release is one of these mechanisms. Prostaglandin F(2alpha) (PGF(2alpha)) analogues, which are used to control ocular hypertension, were reported to induce periocular skin hyperpigmentation. OBJECTIVES: This study aims to evaluate the local effect of three prostaglandin F(2alpha) analogues, namely Latanoprost, Bimatoprost and Travoprost on skin pigmentation. Assessment of the role of combination with narrow band UVB (NB-UVB) to each of these drugs is evaluated as well. METHODS: This study involved 18 female adult wild guinea pigs with patchy white and red/brown fur. The hair was shaved from four red/brown areas on the dorsal skin of each animal. In two areas of each animal, one of the above-mentioned drugs was applied alone and in conjunction with NB-UVB. In the other two areas, the vehicle was applied alone and in conjunction with NB-UVB exposure. Skin biopsies from each area were done at the start of the study and 4 weeks after, and stained with haematoxylin and eosin (H&E) and Masson-Fontana (MF) stains. Clinical and histopathological changes were evaluated. RESULTS: Increased pigmentation was found in all areas with PGF(2alpha) analogues with and without NB-UVB. However, the former group had more effect both clinically and histopathologically. CONCLUSION: PGF(2alpha) analogues are promising drugs in inducing skin pigmentation. This effect can be enhanced with NB-UVB exposure.

The hair follicle melanocytes in vitiligo in relation to disease duration.

BACKGROUND AND AIMS: Vitiligo is an acquired pigmentary disorder of skin and hair. Active melanocytes in hair follicles can be detected by DOPA and immunohistochemical staining, while amelanotic melanocytes can only be detected by the latter. None of the studies on hair melanocytes in vitiligo discussed the effect of disease duration on these melanocytes. Here, we study the presence of melanotic and amelanotic melanocytes in vitiligo hair follicles and statistically correlating their presence with the disease duration. METHODS: This study was conducted on 30 patients with vitiligo and 10 normal volunteers. Three biopsies were taken from each patient: two from black and white hairs from vitiliginous areas and the third from apparently normal skin of the same patients. Sections were stained by DOPA reaction and NKI/beteb then examined for the presence of melanocytes. The presence of melanocytes and the disease duration were correlated statistically using the t-test. RESULTS: Active melanocytes were detected in black hairs of 6.7% of vitiligo patients and in 100% of apparently normal skin of the same patients and controls. On examining black hairs of the 28 vitiligo patients with negative DOPA reaction, 19 of them (67.9%) showed positive NKI/beteb stain. Disease duration was inversely correlated with the melanocytes' presence within hair follicles. Melanocytes were absent from 100% of white hairs. CONCLUSIONS: The melanotic melanocytes were the first target of the disease process followed by the amelanotic melanocytes. Since the disappearance of the latter was inversely correlated with the disease duration, early treatment in vitiligo is advised.

Scaly scalp associated with crusted scabies: case series.

The diagnosis of crusted scabies is becoming more relevant due to the increase in number of immunocompromised patients. To date, more than 200 cases have been reported in the literature. However, crusted scabies seems to be under-diagnosed because of its unusual presentations. In this case series we present history, clinical manifestations, KOH smear, and histopathological findings of a series of four patients with crusted scabies. Scaly scalp was a prominent feature of the disease in all cases. Examination of and treatment of the scalp of patients with suspected crusted scabies should not be neglected. A KOH smear from the scalp offers a simple and reliable technique for diagnosis.

Evaluation of the effects of NB-UVB in both segmental and non-segmental vitiligo affecting different body sites.

BACKGROUND: Narrow band (NB)-UVB has been used in the treatment of vitiligo for years but statistical evaluation of the clinical response in both segmental and non-segmental vitiligo patients has yet to be assessed. OBJECTIVES: Statistical evaluation of the clinical response of vitiligo patients to NB-UVB in both segmental and non-segmental types affecting different body sites. METHODS: This study included 150 patients with vitiligo either segmental (10%) or non-segmental (90%). NB-UVB therapy was given twice weekly till reaching our end point of 100% re-pigmentation or a cut point in unresponsive cases. Evaluation of the percentage of re-pigmentation was performed by total body photography and planimetry every 8 weeks. RESULTS: The overall response to therapy in the non-segmental vitiligo group demonstrated that 48% of the patients showed marked response, 27% showed moderate response and 25% showed mild response after UVB therapy. The patients showed marked response in 76.3% in face lesions, 41.9% in trunk lesions and 37.6% in limbs lesions. None of the patients in the acral areas achieved marked response. The mean duration of therapy was 7.8 months. Moreover, the results demonstrated that the earlier the patient was treated, the better the response was especially for lesions on the face, trunk and limbs. On the other hand, in the segmental vitiligo group, patients showed no more than mild response to NB-UVB whatever the site of the lesion was. No side effects were encountered with NB-UVB therapy except for aggravation of the disease in two cases and erythema in one patient who was an outdoor worker and was skin type II. CONCLUSION: The type of vitiligo, the affected anatomical area and the disease duration are important factors that influence potential re-pigmentation.

Density of viral particles in pre and post Nd: YAG laser hyperthermia therapy and cryotherapy in plantar warts.

BACKGROUND: Warts often present a difficult treatment problem for clinicians because of the lack of specific antipapillomavirus agents. Plantar warts, in particular, represent a therapeutic challenge. METHODS: Twenty-five patients with plantar warts were treated with Nd:YAG hyperthermia and another 25 were treated with cryotherapy. Biopsies were taken before and after treatment in both groups and were examined for the presence of human papillomavirus deoxyribonucleic acid (HPV DNA) using in situ hybridization (ISH). RESULTS: HPV DNA was detected in 100% of untreated warts and in 96% of cryotreated warts, but was not detected in any of the hyperthermia-treated warts. CONCLUSIONS: HPV is more vulnerable to hyperthermia than to cryotherapy.