Search

The treatment of postburn hypopigmentation was primarily surgical before the advent of new technologies. Medical devices and therapies are emerging to manage scar sequelae that can be disfiguring and associated with severe psychosocial impact. These innovations have been poorly investigated for hypopigmentation, but they represent a real hope. We reviewed all articles published on Pubmed up to June 2022. Included studies had to specifically focus on treating postburn hypopigmented scars. All articles evaluating transient solutions such as make-up, and articles describing inflammation-linked hypopigmentation with no etiological details or no burn injury history were excluded. Through this review, we have highlighted 6 different types of nonsurgical treatments reported in postburn leukoderma potentially allowing definitive results. Electrophoto-biomodulation or E light (combining intensive pulsed light, radiofrequency, and cooling), topical daylight psoralen UVA therapy, and lasers (fractional lasers using pulse energies or CO2FL devices, lasers-assisted drug delivery as local bimatoprost and tretinoin or pimecrolimus) have been explored with encouraging results in hypopigmented burns. Finally, other promising medical strategies include using FK506, a nonsteroidal anti-inflammatory drug, to induce melanogenesis or using melanocyte-stimulating hormones with fractional laser-assisted drug deliveries, which are expected to emerge soon. [ABSTRACT FROM AUTHOR]

Background In Western countries, lichen sclerosus is a common disease that affects commonly middle-aged females that present most commonly as a disease of genital and anal regions in both sexes while extra-genital involvement is less frequent. Objective To record all cases of lichen sclerosus in Iraqi population as one of Middle East country and to do a full clinical evaluation and to be compared with published literature as seen in Western countries. Methods This is a cross-sectional descriptive study where all patients with lichen sclerosus were recorded during the period from 2013-2022. All demographic features were estimated and full history and examination were carried out. A histopathological assessment was performed as a confirmatory test. Results All data related to 28 patients with lichen sclerosus were registered and evaluated. The age of patients has a bimodal peak in incidence from prepubertal to a postmenopausal age group and ranged from 8-63 years with a median of 40 years with 24 (85.7%) females and 4 (14.2%) males with a ratio of 6:1. The clinical features of the disease were found to be genital involvement in three (10.7%) patients, one male with follicular lesions of penis and two females with vulval involvement: one with extensive atrophy of vulva while the other with very early lesions). While 25 (89.2%) cases with extragenital sites where the trunk and limbs were the main locations but lips were affected in one female patient another one the ears were involved. The primary lesions in almost half of the cases were follicular whitish sclerosed macules, some with follicular plugs. These lesions over time coalesced together into larger whitish ivory leukoderma in the form of patches and plaques. The rash was localized in 22 (78.6%) cases while extensive in 5 (17.9%) patients. The lesion was asymptomatic apart from slight discomfort and itching but was severe intractable itching in the female genitalia. The HE-stained sections showed complete atrophy of the epidermis with complete sclerosis of the dermis leaving sub-epidermal cleft. Conclusion Lichen sclerosus is a disease of females that commonly presents with extragenital whitish sclerosed leukoderma in the form of follicular macules, patches and plaques while female genital involvement is a rare presentation. The likelihood of extragenital lichen sclerosus following the Blaschko lines was pronounced. [ABSTRACT FROM AUTHOR]

Vitiligo patients may desire laser hair removal, skin rejuvenation, vascular treatments, and other laser or intense pulsed light (IPL) assisted treatments. However, there is a risk of inducing new depigmented patches (Koebner phenomenon). In absence of guidelines on the safe use of laser or IPL in vitiligo patients, dermatologists tend to be reluctant to administer these treatments. The aim of this survey study was to provide an estimation of the occurrence and related risk factors of laser/IPL-induced leukoderma or vitiligo. A cross-sectional survey study was performed among 15 vitiligo experts from 11 countries, with 14 questions about affected patients, involved laser/IPL treatments and the physicians' approach. In a total of 11,300 vitiligo patients, laser/IPL-induced leukoderma or vitiligo was reported in 30 patients (0.27%). Of these, 12 (40%) patients had a medical history of vitiligo and seven (58%) of these patients had stable (> 12 months) vitiligo before the treatment. Most frequently reported were hair removal procedures and localization of the face and legs. Side effects like blistering, crusting, and erosions occurred in 56.7% of the cases. These vitiligo experts based their advice on the risk of the laser treatment on stability of the vitiligo (43%) and activity signs (50%), and 50% discuss the risks before starting a laser treatment. Relevant activity signs are the Koebner phenomenon (57.1%), confetti-like lesions (57.1%) and hypochromic borders (50%). Laser-induced leukoderma or vitiligo is an uncommon phenomenon. Remarkably, a minority had a medical history of vitiligo of which 58% were stable. Consequently, most cases could not have been prevented by not treating vitiligo patients. However, a majority had laser/IPL-induced skin damage. Therefore, caution is advised with aggressive settings and test-spots prior to the treatment are recommended. This study showed significant variation in the current recommendations and approach of vitiligo experts regarding laser/IPL-induced leukoderma or vitiligo. [ABSTRACT FROM AUTHOR]

Background: The autologous noncultured melanocyte keratinocyte transplant procedure (MKTP) has emerged as a popular grafting technique with proven efficacy for achieving repigmentation. However, there remains no consensus regarding the optimal recipient-to-donor (RD) ratio required to achieve acceptable repigmentation. In this retrospective cohort study of 120 patients, we sought to examine whether expansion ratios impact the repigmentation success rates following MKTP. Results: A total of 69 patients (mean [SD] age was 32.4 [14.3] years, mean follow-up was 30.4 [22.5] months, 63.8% were male; 55% were dark-skinned individuals [Fitzpatrick IV–VI]) were included. The mean percent change in the Vitiligo Area Scoring Index (VASI) was 80.2 (±23.7; RD of 7.3) in patients with focal/segmental vitiligo (SV), 58.3 (±33.0; RD of 8.2) in those with non-segmental vitiligo (NSV), and 51.8 (±33.6; RD of 3.7) in those with leukoderma and piebaldism. Focal/SV was positively associated with a higher percent change in VASI (parameter estimate: 22.6, p value <0.005). In the SV/focal group, non-white patients had a higher RD ratio compared to White individuals (8.2 ± 3.4 vs. 6.0 ± 3.1, respectively, p value = 0.035). Discussion: In our study, we found that patients with SV were significantly more likely to achieve higher repigmentation rates compared to those with NSV. Although repigmentation rates were higher in the low expansion ratio group than in the high expansion ratio group, we did not observe a significant difference between the two groups. Conclusion: MKTP is an effective therapy for restoring repigmentation in patients with stable vitiligo. Therapeutic response of vitiligo to MKTP appears to be influenced by the type of vitiligo, rather than a specific RD ratio. [ABSTRACT FROM AUTHOR]

Resumen: Introducción: La hipopigmentación post-quemadura (HPQ) es una complicación frecuente en pacientes quemados, generando secuelas permanentes. El tratamiento es complejo, con escasa evidencia, e incluye el uso de procedimientos quirúrgicos descritos principalmente en reportes de casos y series de pacientes.El objetivo de este trabajo fue describir las diferentes técnicas quirúrgicas disponibles en la literatura para el tratamiento de la HPQ. Metodología: Se realizó una revisión sistemática en Medline, Embase, PubMed, Cochrane y LILACS, incluyendo casos clínicos, series de casos, y artículos originales en inglés y español, que describieran técnicas quirúrgicas para el manejo de la HPQ crónica, hasta septiembre de 2020. Resultados: Veintisiete artículos cumplían con los criterios de inclusión, describiendo siete técnicas quirúrgicas para el manejo de la HPQ: injerto cutáneo de espesor parcial, injerto epidérmico mediante ampollas, mini-injerto por punch, injerto de pequeños fragmentos epidérmicos, trasplante de queratinocitos-melanocitos no cultivados, autoinjerto de epitelio cultivado, y aprovechamiento de unidades foliculares. Estas técnicas fueron aplicadas en 301 pacientes, entre 5 y 68 años, 58% sexo femenino, incluyendo principalmente pacientes asiáticos, hispanos y afrodescendientes. Las principales localizaciones corporales tratadas fueron extremidades superiores, área facial y extremidades inferiores. Con todas las técnicas se describe repigmentación significativa, siendo la principal complicación la hiperpigmentación de la zona tratada. Discusión - Conclusión: Existen siete técnicas quirúrgicas descritas para el manejo de la HPQ, sin embargo, faltan estudios comparativos de mayor calidad, por lo que la selección de la técnica dependerá de la experiencia clínica, disponibilidad de recursos técnicos, y las características individuales de cada paciente. Abstract: Introduction: Post-burn hypopigmentation (PBH) is a frequent complication in burned patients, which may generate permanent sequelae. Treatment is complex, with limited evidence available, and includes the use of surgical procedures described mainly in case reports and case series.The objective of this manuscript was to describe the different surgical techniques available in the literature for the treatment of PBH. Methodology: A systematic review was carried out in Medline, Embase, PubMed, Cochrane and LILACS databases, including clinical cases, case series, and original articles written in English and Spanish, which described surgical techniques for the management of chronic PBH, until September 2020. Results: Twenty seven articles met the inclusion criteria, which described seven surgical techniques for the management of PBH, including: superficial dermabrasion with split thickness skin grafting, blister epidermal grafting, punch minigrafting, chip skin grafting, non-cultured keratinocyte-melanocyte transplantation, cultured epithelium autograft, and follicular unit exploitation. These techniques were applied in 301 patients, between 5 and 68 years old, 58% female, mainly Asian, Hispanic and Afro-descendant patients. The main body locations treated were upper extremities, facial area and lower extremities. Significant repigmentation is described with all the techniques, and the main complication was hyperpigmentation of the treated area. Discussion and conclusion: There are seven surgical techniques described for the management of PBH, however, higher quality comparative studies are needed, therefore, the selection of the technique depends on clinical experience, availability of technical resources, and the individual characteristics of each patient.

Oxidative metabolism of rhododendrol (RD), a skin-whitening ingredient, by tyrosinase has caused leukoderma in a certain population of Japanese consumers. Toxic RD metabolites and reactive oxygen species are proposed causes for the melanocyte death. However, the mechanism by which reactive oxygen species are produced during RD metabolism remains elusive. Some phenolic compounds are known to act as suicide substrates for tyrosinase, resulting in release of a copper atom and hydrogen peroxide during its inactivation. We hypothesized that RD may be a suicide substrate for tyrosinase and that the released copper atom may be responsible for the melanocyte death through hydroxyl radical production. In line with this hypothesis, human melanocytes incubated with RD showed an irreversible decrease in tyrosinase activity and underwent cell death. A copper chelator, d -penicillamine, markedly suppressed the RD-dependent cell death without significantly affecting the tyrosinase activity. Peroxide levels in RD-treated cells were not affected by d -penicillamine. Given the unique enzymatic properties of tyrosinase, we conclude that RD acted as a suicide substrate and resulted in release of a copper atom and hydrogen peroxide, which would collectively impair melanocyte viability. These observations further imply that copper chelation may alleviate chemical leukoderma caused by other compounds. [Display omitted] • Rhododendrol (RD) inactivates tyrosinase in human primary melanocytes. • Copper chelation effectively alleviates RD-triggered melanocyte death. • Suicide substrate nature of RD is responsible for melanocyte death and leukoderma. [ABSTRACT FROM AUTHOR]

Copyright of Revista Médica Clínica Las Condes is the property of Editorial Sanchez y Barcelo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Leukoderma, or hypomelanosis of the skin, can occur in response to various chemical and pharmacologic substances ranging from topical medications to optic preparations and systemic medications. In this case report, we present a 78-year-old man with a history of restless leg syndrome (RLS) who had been using rotigotine transdermal patches once daily for 1 year and developed leukoderma on the bilateral anterior shoulders in the area of patch application. Histopathologic examination showed an absence of melanocytes at the dermal-epidermal junction confirmed by Melan A stain. While the patient was not bothered by the depigmentation and elected to continue the rotigotine patch for his RLS, this case highlights leukoderma as a potential side effect of dopamine transdermal patches and offers insight into the potential mechanism of hypopigmentation in response to dopamine agonism.

The Indo-Pacific humpback dolphin is characterized by a particular ontogenic change in body color from dark gray at birth to pure white (or with a few dark-gray spots) after reaching adulthood. Here, we report a spectrum of anomalous body color patterns observed on Indo-Pacific humpback dolphins off southern China. The occurrence of hypopigmentation and hyperpigmentation was described and compared among six putative dolphin populations. Low rates of anomalies in body color patterns were observed (<1%), except for hypopigmentation, which was prevalent in dolphins residing in the mid-Pearl-River-Delta region (3.3%). [ABSTRACT FROM AUTHOR]

Vitiligo‐like changes are an uncommon cutaneous manifestation of graft‐versus‐host disease (GVHD). We report three cases and review the literature of pediatric patients with vitiligo‐like changes associated with GVHD. Improved characterization of this phenomenon may lend insight into the biologic pathways that underlie both vitiligo and GVHD. [ABSTRACT FROM AUTHOR]

The tyrosinase inhibitor rhododendrol (RD), used as a skin whitening agent, reportedly has the potential to induce leukoderma. Although an immune response toward melanocytes was demonstrated to be involved in leukoderma, the molecular mechanism is not fully understood. We hypothesized that if RD is a pro-hapten and tyrosinase-oxidized RD metabolites are melanocyte-specific sensitizers, the sensitizing process could be reproduced by the human cell line activation test (h-CLAT) cocultured with melanocytes (h-CLATw/M) composed of human DC THP-1 cells and melanoma SK-MEL-37 cells. Cell surface expression, ROS generation and ATP release, mRNA expression, and the effects of several inhibitors were examined. When RD was added to the h-CLATw/M, the expression of cell-surface CD86 and IL-12 mRNA was greatly enhanced in THP-1 cells compared with those in the h-CLAT. The rapid death of melanoma cells was induced, with ROS generation and ATP release subsequently being greatly enhanced, resulting in the cooperative upregulation of CD86 and IL-12. Consistent with those observations, an ROS inhibitor, ATP receptor P2X7 antagonist, or PERK inhibitor antagonized the upregulation. CD86 upregulation was similarly observed with another leukoderma-inducible tyrosinase inhibitor, raspberry ketone, but not with the leukoderma noninducible skin-whitening agents ascorbic acid and tranexamic acid. RD is a pro-hapten sensitizer dependent on tyrosinase that induces ROS generation and ATP release from melanocytes for CD86 and IL-12 upregulation in DCs, possibly leading to the generation of tyrosinase-specific cytotoxic T lymphocytes. The coculture system h-CLATw/M may be useful for predicting the sensitizing potential to induce leukoderma. • A new h-CLATw/M composed of THP-1 cells and melanoma SK-MEL-37 cells was established. • RD upregulates CD86 and IL-12 in THP-1 via ROS and ATP production from SK-MEL-37. • h-CLATw/M can distinguish between leukoderma-inducible and non-inducible agents. • RD is a pro-hapten dependent on tyrosinase, possibly leading to CTL generation. • h-CLATw/M would be useful to predict the sensitizing potential to induce leukoderma. [ABSTRACT FROM AUTHOR]

Purpose: Although development of immune checkpoint inhibitors has revolutionized the treatment of metastatic melanoma, more than a half of treated patients experience disease progression during therapy. Cases of spontaneous vitiligo-like leukoderma have been described in melanoma patients and have been associated with a favorable outcome. This vitiligo-like leukoderma can also appear in melanoma patients undergoing immune therapies such as immune checkpoint inhibitors. However, no consensus exists about the relationship between vitiligo-like leukoderma onset and improved overall survival. Our study investigates the possible association between the onset of vitiligo-like leukoderma during immune checkpoint inhibitor treatment and a better prognosis. Methods: A non-concurrent cohort study was conducted by identifying retrospectively 280 patients who had inoperable or metastatic melanoma and had undergone immune therapy with checkpoint inhibitors in any line of treatment. Toxicities developed during therapy were evaluated. Results: Among the 280 study participants, 50% developed at least one type of toxicity, and vitiligo-like leukoderma was observed in 43 patients (15.4%). In the multivariate Cox model, a protective effect for mortality was observed for patients with vitiligo-like leukoderma development (HR : 0.23; 95% CI 0.11–0.44, p < 0.0001). In a sub-group analysis comprising only cutaneous melanoma in first line of treatment (N = 153), occurrence of vitiligo-like leukoderma was also an independent predictor factor for duration of clinical benefits measured by time to the next treatment (HR: 0.17; 95% CI 0.06–0.44). Conclusion: Our findings indicate that onset of vitiligo-like leukoderma during melanoma treatment could be a marker of favorable outcome in patients treated with immune checkpoint inhibitors. [ABSTRACT FROM AUTHOR]

Keywords: acrylates; allergic contact dermatitis; case report; construction worker; leukoderma; marble; methacrylates; methylisothiazolinone; occupational; resin EN acrylates allergic contact dermatitis case report construction worker leukoderma marble methacrylates methylisothiazolinone occupational resin 242 244 3 02/08/23 20230301 NES 230301 Plastics/resins have become an emerging cause of occupational allergic contact dermatitis (OACD) in construction workers, mainly related to exposure to epoxy resin systems. Allergic contact dermatitis, case report, construction worker, acrylates, marble, methacrylates, methylisothiazolinone, occupational, resin, leukoderma 5 d Toledo University Hospital Acrylate series: methyl methacrylate, butyl methacrylate, 2-HEMA, 2-HPMA, EGDMA, triethyleneglycol dimethacrylate, 1,4-butanediol dimethacrylate, urethane dimethacrylate, bisphenol-A-dimethacrylate, bisphenol A glycerolate dimethacrylate, 1,6 hexanediol diacrylate, tetrahydrofurfuryl methacrylate, tetraethyleneglycol dimethacrylate, dimethylaminoethyl methacrylate, ethyl cyanoacrylate, ethyl methacrylate, isobornyl acrylate, butyl acrylate, 2-hydroxyethyl acrylate, benzoyl peroxide, bisphenol A (Chemotechnique Diagnostics). [Extracted from the article]

Leukoderma, or hypomelanosis of the skin, can occur in response to various chemical and pharmacologic substances ranging from topical medications to optic preparations and systemic medications. In this case report, we present a 78-year-old man with a history of restless leg syndrome (RLS) who had been using rotigotine transdermal patches once daily for 1 year and developed leukoderma on the bilateral anterior shoulders in the area of patch application. Histopathologic examination showed an absence of melanocytes at the dermal-epidermal junction confirmed by Melan A stain. While the patient was not bothered by the depigmentation and elected to continue the rotigotine patch for his RLS, this case highlights leukoderma as a potential side effect of dopamine transdermal patches and offers insight into the potential mechanism of hypopigmentation in response to dopamine agonism. [ABSTRACT FROM AUTHOR]

The Indo-Pacific humpback dolphin is characterized by a particular ontogenic change in body color from dark gray at birth to pure white (or with a few dark-gray spots) after reaching adulthood. Here, we report a spectrum of anomalous body color patterns observed on Indo-Pacific humpback dolphins off southern China. The occurrence of hypopigmentation and hyperpigmentation was described and compared among six putative dolphin populations. Low rates of anomalies in body color patterns were observed (

Disorders of hyperpigmentation are extremely common, and hydroquinone remains one of the most common treatments for hyperpigmentation. Adverse events reported with hydroquinone use include acneiform eruptions, ochronosis, and irritant dermatitis; leukoderma has been reported in rare instances. Largely, these cases report leukoderma localized to the site of application. However, we report a case of diffuse facial leukoderma with only localized use of hydroquinone. With appropriate and prompt treatment, this leukoderma can respond to vitiligo treatment algorithms., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Artz et al.)

Idiopathic leukoderma is a skin disorder characterized by patchy loss of skin pigmentation due to melanocyte dysfunction or deficiency. Rhododendrol (RD) was approved as a cosmetic ingredient in Japan in 2008. However, it was shown to induce leukoderma in approximately 20,000 customers. The prediction of cytotoxicity, especially to melanocytes in vivo, is required to avoid such adverse effects. Since the use of higher vertebrates is prohibited for medicinal and toxicological assays, we used zebrafish, whose melanocytes were regulated by mechanisms similar to mammals. Zebrafish larvae were treated with RD in breeding water for 3 days, which caused body lightening accompanied by a decrease in the number of melanophores. Interestingly, black particles were found at the bottom of culture dishes, suggesting that the melanophores peeled off from the body. In addition, RT‐PCR analysis suggested that the mRNA levels of melanophore‐specific genes were significantly low. An increase in the production of reactive oxygen species was found in larvae treated with RD. The treatments of the fish with other phenol compounds, which have been reported to cause leukoderma, also induced depigmentation and melanophore loss. These results suggest that zebrafish larvae could be used for the evaluation of leukoderma caused by chemicals, including RD. [ABSTRACT FROM AUTHOR]

Cutaneous malignant melanoma is a rapidly progressing skin tumor accounting for most deaths from skin malignancies. Four morphological variants (nodular, superficial spreading, lentigo maligna, and acral lentiginous) are described in the literature. Here we are reporting malignant melanoma in a 35-year-old male who presented with depigmented plaques with few hyperpigmented areas and extensive overlying scaling. The patient progressed to the nodular stage within 2 weeks and succumbed to death during chemotherapy. We are reporting such rare presentation of malignant melanoma to create awareness among dermatologists to avoid misdiagnosis and delayed treatment which can lead to rapid progression and fatal outcome.

The aim of this study was to assess the efficacy of non-cultured autologous epidermal cell grafting resuspended in hyaluronic acid, performed using a ready-to-use kit, compared with hyaluronic acid alone (neutral comparator) for repigmenting vitiligo and piebaldism lesions at 6 months. Two identified paired lesions per patient were randomized to be treated by either device. Devices with a ready-to-use kit were prepared by separate health professionals, to maintain blinding. A skin biopsy was digested using trypsin, and cells resuspended in hyaluronic acid solution. Among 38 patients screened, 36 (94.7%) patients, corresponding to 72 lesions, were analysed. For difficult-to-treat lesions, defined as those located on the wrist, elbow, and hands (n = 30), no repigmentation ≥ 50% was observed. For all other locations (n = 42), the success rate was significantly higher (p = 0.021) in the ready-to-use kit group (47.6% vs 9.5%) at 6 months and was maintained until 12 months. In conclusion, a single application of non-cultured epidermal cellular grafting using a ready-to-use kit was efficient at 6 months and at 1-year follow-up.

The aim of this study was to assess the efficacy of noncultured autologous epidermal cell grafting resuspended in hyaluronic acid, performed using a ready-to-use kit, compared with hyaluronic acid alone (neutral comparator) for repigmenting vitiligo and piebaldism lesions at 6 months. Two identified paired lesions per patient were randomized to be treated by either device. Devices with a ready-to-use kit were prepared by separate health professionals, to maintain blinding. A skin biopsy was digested using trypsin, and cells resuspended in hyaluronic acid solution. Among 38 patients screened, 36 (94.7%) patients, corresponding to 72 lesions, were analysed. For difficult-to-treat lesions, defined as those located on the wrist, elbow, and hands (n = 30), no repigmentation = 50% was observed. For all other locations (n = 42), the success rate was significantly higher (p = 0.021) in the ready-to-use kit group (47.6% vs 9.5%) at 6 months and was maintained until 12 months. In conclusion, a single application of non-cultured epidermal cellular grafting using a ready-to-use kit was efficient at 6 months and at 1-year follow-up. [ABSTRACT FROM AUTHOR]

A small proportion of individuals utilizing cosmetics containing rhododendrol developed leukoderma with various pathological conditions, in some cases indistinguishable from vitiligo. In this review, we investigate and evaluate the major considerations for developing rhododendrol‐induced leukoderma based on data from original or review articles published in the literature to provide a wide range of information regarding the pathophysiology, mechanisms, risk evaluation, and possible mechanism‐based treatments. We compile and discuss the latest information, including data related to the cytotoxicity of rhododendrol, cytoprotective functions, and involvement of the immune system, and consider the possibility of novel treatments based on the differences between individual patients and on the mechanism underlying the onset of the condition. Understanding the pathophysiology of rhododendrol‐induced leukoderma helps not only elucidate the mechanisms of non‐segmental vitiligo onset and progression, but also suggests prevention and treatment. [ABSTRACT FROM AUTHOR]

Abstract Autoimmune dermatoses targeting melanocytes have gained attention in human medicine due to their progressive nature and the social impact suffered by affected individuals. In veterinary medicine, vitiligo and the uveodermatological syndrome are the two autoimmune diseases that are known to affect skin melanocytes. In the first part of this article, we will review the signalment, clinical signs, histopathology and the treatment outcome of vitiligo in dogs, cats and horses; where pertinent, we compare the animal diseases to their human homologue. In a similar fashion, the information on the uveodermatological syndrome in dogs is reviewed and, where relevant, it is compared to the Vogt-Koyanagi-Harada (VKH) syndrome in humans. Canine, feline and equine vitiligo have many features that mirror their human counterparts. The most effective treatment and outcome of vitiligo in animals remain unclear. The canine uveodermatological syndrome resembles the incomplete VKH variant in humans; for affected individuals, an immediate diagnosis and aggressive treatment are crucial to prevent the development of blindness.

Abstract is missing (Short communication)

Introduction: Endemic non-filarial elephantiasis also known as podoconiosis often affects bare footed farmers and is endemic in Ethiopia. The disease is prevented by wearing shoes. We recently observed several patients presenting to a dermatology clinic with skin depigmentation after wearing plastic shoes ("shoe-contact vitiligo") which may deter shoe-wearing. We report on their sociodemographic and clinical characteristics. Methodology: This is a retrospective study of 17 months at tertiary level Hospital in Ethiopia. Patient data was retrieved from medical record department. We compared sociodemographic and clinical characteristics of patients presenting with idiopathic and shoe-contact vitiligo. Data was presented descriptively. Results: Of 460 vitiligo cases, 190 (41%) were shoe-contact vitiligo and the rest, idiopathic. The former was more common in females (Odds Ratio, OR = 2.5, P < 0.001) and those in rural areas (OR = 4.8, P < 0.001). Fifty-five percent with shoe-contact vitiligo had itching and/or burning sensation, compared to just 2% with idiopathic vitiligo (P < 0.001) and some had ulcerations (8%). Idiopathic vitiligo had no such findings. Skin discoloration occurred within three weeks (on average) after wearing plastic shoes, 91% of lesions were symmetrical and involved areas of the feet covered with plastic shoes. Symmetric lesions were observed in only 11% of idiopathic vitiligo (OR = 81, P < 0.001). Conclusions: Shoe-contact vitiligo was significantly associated with wearing cheap plastic shoes. The exact chemical culprit(s) needs to be identified. This will allow introducing quality control regulations and rigorous monitoring of shoe production sites. [ABSTRACT FROM AUTHOR]

Sanqi, a traditional Chinese herb, is widely used for cardiovascular diseases, and its neuroprotective effects against oxidative stress were recently discovered. The purpose of this study was to investigate whether Sanqi-derived compound K (Sanqi-CK), an active metabolite of Sanqi, could protect melanocytes from oxidative stress. Cultured human primary skin epidermal melanocytes (HEMn-MPs) were treated with hydrogen peroxide (H2O2) in the presence or absence of Sanqi-CK. Sanqi-CK exhibited protective effects against H2O2-induced cell death by reducing oxidative stress. In addition, treatment with Sanqi-CK reversed the decreased glutathione reductase activity and decreased ratio of reduced glutathione (GSH)/oxidized glutathione (GSSG) seen in H2O2-treated melanocytes. Furthermore, topical application of Sanqi-CK alleviated leukoderma in guinea pigs, a disorder characterized by melanocyte cell death resulting from rhododendrol-induced oxidative stress. Taken together, these data suggest that Sanqi-CK protects melanocytes against oxidative stress, and its protective effects are associated with modulating the redox balance between GSH and GSSG and activating glutathione reductase. Thus, Sanqi-CK may be a good candidate for preventing melanocyte loss in oxidative-stress-associated pigmentary disorders.

The role of Langerhans cells (LCs) in vitiligo pathogenesis remains unclear, with published studies reporting contradictory results regarding the quantity of LCs and no data on the features of LCs in vitiligo. Here, we aimed to analyze the presence, density, and morphological features of LCs in the epidermis of patients with vitiligo. Skin biopsies were stained for LCs using anti-CD1a/anti-langerin antibodies and analyzed by immunocytochemistry with light and electron microscopy. Compared with healthy controls, we detected significantly increased numbers of epidermal LCs in lesional skin from vitiligo in the progressive state. These LCs exhibited striking morphological alterations, including an elevated number of dendrites, with increased length and more branches than dendrites from controls. Ultrastructure examination via immuno-electron microscopy revealed markedly reduced Birbeck granules (BGs) and shorter BG rods in LCs from progressive vitiligo, with higher expression of langerin. Additionally, expression of S100B, the activity biomarker of vitiligo, was increased in these LCs. This work provides new insight on the cellular composition of LCs in vitiliginous skin, revealing altered morphology and increased LC numbers, with elevated S100B expression. Our data suggest LCs might play a critical role in vitiligo pathogenesis and thus may represent a novel therapeutic target for this disease.

Monobenzone is a 4‐substituted phenol that can induce vitiligo and antimelanoma immunity. We investigated the influence of the chemical structure on the biological activity of a series of structurally related 4‐substituted phenols. All phenols inhibited cellular melanin synthesis, and eight of ten phenols inhibited tyrosinase activity, using the MBTH assay. These phenols also induced glutathione (GSH) depletion, indicative of quinone formation and protein thiol binding, which can increase the immunogenicity of melanosomal proteins. Specific T‐cell activation was found upon stimulation with phenol‐exposed pigmented cells, which also reacted with unexposed cells. In contrast, 4‐tertbutylphenol induced immune activation was not restricted to pigment cells, analogous to contact sensitization. We conclude that 4‐substituted phenols can induce specific T‐cell responses against melanocytes and melanoma cells, also acting at distant, unexposed body sites, and may confer a risk of chemical vitiligo. Conversely, these phenols may be applicable to induce specific antimelanoma immunity. [ABSTRACT FROM AUTHOR]

Melanocyte development is orchestrated by a complex interconnecting regulatory network of genes and synergistic interactions. Piebaldism and Waardenburg syndrome are neurocristopathies that arise from mutations in genes involved in this complex network. Our understanding of melanocyte development, Piebaldism, and Waardenburg syndrome has improved dramatically over the past decade. The diagnosis and classification of Waardenburg syndrome, first proposed in 1992 and based on phenotype, have expanded over the past three decades to include genotype. This review focuses on the current understanding of human melanocyte development and the evaluation and management of Piebaldism and Waardenburg syndrome. Management is often challenging and requires a multidisciplinary approach. [ABSTRACT FROM AUTHOR]

Leukoderma secondary to Q‐switched 1064‐nm neodymium‐doped yttrium aluminium garnet laser is usually refractory to treatment. The pathogenesis was cumulative phototoxic damage to melanocytes and eventually resulted in melanocytopenia. Wood's light or UV imaging can help observe early leukoderma before it becomes apparent clinically and determine the degree of melanocytopenia before conducting a biopsy. NB‐UVB phototherapy and 308‐nm excimer laser can potentially worsen the pre‐existing melasma lesions and may not be effective if the lesions have already become melanocytopenic. Epidermal grafting can replenish the hypopigmented area with melanocytes without worsening melasma. [ABSTRACT FROM AUTHOR]

Cutaneous malignant melanoma is a rapidly progressing skin tumor accounting for most deaths from skin malignancies. Four morphological variants (nodular, superficial spreading, lentigo maligna, and acral lentiginous) are described in the literature. Here we are reporting malignant melanoma in a 35-year-old male who presented with depigmented plaques with few hyperpigmented areas and extensive overlying scaling. The patient progressed to the nodular stage within 2 weeks and succumbed to death during chemotherapy. We are reporting such rare presentation of malignant melanoma to create awareness among dermatologists to avoid misdiagnosis and delayed treatment which can lead to rapid progression and fatal outcome. [ABSTRACT FROM AUTHOR]

Abstract is missing (Short communication)

Postburn leukoderma is challenging to treat with different surgical and nonsurgical treatments resulting in variable outcomes. We report a case of a 56‐year‐old female with postburn leukoderma treated successfully with topical daylight psoralen UVA therapy for 6 months. The treatment was well tolerated and showed excellent improvement. In conclusion, we report the successful use of topical daylight PUVA for postburn leukoderma with almost complete repigmentation. This is a simple, convenient, and cheap nonsurgical treatment option. [ABSTRACT FROM AUTHOR]

Keywords: allergic contact dermatitis; case report; FreeStyle Libre; glucose sensor; hydroquinone monomethyl ether; hypopigmentation; isobornyl acrylate; leukoderma; medical device Allergic contact dermatitis, case report, FreeStyle Libre, glucose sensor, hydroquinone monomethyl ether, hypopigmentation, isobornyl acrylate, leukoderma, medical device. [Extracted from the article]

Rhododendrol (RD), 4‐(4‐hydroxyphenyl)‐2‐butanol, inhibits melanin synthesis and had been used in skin‐whitening cosmetic products until 2013. However, some individuals developed leukoderma on the skin where RD had been applied and have suffered from refractory depigmentation even after discontinuing RD application. Bimatoprost is a prostaglandin F2α analog and is often used for eyelash growth for cosmetic reasons as well as in the treatment of glaucoma. It was reported that bimatoprost induced skin pigmentation in addition to iris pigmentation as adverse effects. Therefore, we conducted an open‐label single‐center pilot study to evaluate the effectiveness of bimatoprost on refractory RD‐induced leukoderma. Eleven Japanese female patients with skin type III who developed leukoderma on the exact or slightly extended area of skin where RD had been applied and gained a halt of enlargement of leukoderma or repigmentation on a part of the affected skin after discontinuation of RD were enrolled. Bimatoprost 0.03% solution was applied on the leukoderma once daily for 3 months, and then the frequency of application was increased to twice daily for the subsequent 3 months. Ten patients completed the 6‐month course of bimatoprost application. In four patients, bimatoprost application brought slight improvement in RD‐induced refractory leukoderma by dermatologists' evaluation. Because the number of enrolled patients was limited, further larger studies are necessary to better assess the effectiveness of bimatoprost in inducing repigmentation in patients with RD‐induced refractory leukoderma. [ABSTRACT FROM AUTHOR]

Highlights • Elaborate hydroxyl radical detection after rhododendrol application to melanocytes. • Remarkable correlation of hydroxyl radical generation with melanocyte cytotoxicity. • Suppressing both hydroxyl radicals and cytotoxicity by enhancing glutathione levels. • Useful strategy to prevent leukoderma induced by phenol derivatives. Abstract Background Rhododendrol (4-(4-hydroxyphenyl)-2-butanol) has been used as a lightening/whitening cosmetic but was recently reported to induce leukoderma. Although rhododendrol has been shown to be transformed by tyrosinase to hydroxyl-rhododendrol, which is cytotoxic to melanocytes, its detailed mechanism of action including the involvement of reactive oxygen species is not clearly understood. Objective To confirm the relationship of hydroxyl radical generation to melanocyte cytotoxicity induced by rhododendrol, this study was performed. Methods An electron spin resonance method with a highly sensitive detection system was utilized to monitor hydroxyl radicals generated from two distinct normal human epidermal melanocyte lines with different levels of tyrosinase activity after the addition of various amounts of rhododendrol. Cytotoxicity of rhododendrol was analyzed by AlamarBlue assay under the same condition. Results Hydroxyl radicals were generated depending on the amounts of rhododendrol and/or tyrosinase. After the correlation between hydroxyl radical generation with melanocyte viability was confirmed, an inhibitor of oxidative stress, N -acetyl cysteine, was shown to dramatically diminish rhododendrol-induced generation of hydroxyl radicals and melanocyte cytotoxicity by increasing glutathione levels. In contrast, buthionine sulfoximine, which depletes glutathione, augmented both of those parameters. Conclusion Suppressing oxidative stress would prevent and/or mitigate some phenol derivative-induced leukoderma by avoiding hydroxyl radical-initiated melanocyte cytotoxicity. [ABSTRACT FROM AUTHOR]

Background: Persistence of pigmentation after a melanocyte-keratinocyte transplantation procedure (MKTP) is an important consideration for efficacy.Objective: We sought to determine long-term repigmentation of MKTP in vitiligo and other leukodermas.Methods: A retrospective review of electronic medical records was conducted for all MKTPs performed at Henry Ford Hospital between January 2009 and April 2014. Repigmentation was assessed by a 5-point grading scale (poor to excellent) and Vitiligo Area Scoring Index (VASI).Results: One hundred patients had MKTP performed at 236 anatomically-based lesions (ABLs); 63 patients with 157 ABLs had long-term data available (12-72 months; median, 24 months). Segmental vitiligo, nonsegmental vitiligo, and physical leukoderma demonstrated improvement in VASI scores: -75.6 ± 24.6%, -59.2 ± 36.6%, and -32.4 ± 33.5%, respectively. In vitiligo, at 24, 48, and 72 months after MKTP, 53%, 64%, and 53% of ABLs, respectively, maintained >75% repigmentation. Skin phototype, age, and anatomic location of ABLs had no significant effect on the outcome of treatment.Limitations: Limitations of the study include the retrospective design with uncontrolled, postoperative adjuvant treatments and inconsistent compliance to scheduled follow-up evaluations.Conclusions: MKTP provides satisfactory long-term repigmentation in the majority of appropriately selected patients with leukoderma. MKTP can maintain repigmentation for at least 72 months. [ABSTRACT FROM AUTHOR]

Clinicians should be aware that vitiligo is not merely a cosmetic disease and that there are safe and effective treatments available for vitiligo. It is important to recognize common and uncommon presentations and those with active disease, as well as their implications for clinical management; these were discussed in the first article in this continuing medical education series. Existing treatments include topical and systemic immunosuppressants, phototherapy, and surgical techniques, which together may serve to halt disease progression, stabilize depigmented lesions, and encourage repigmentation. We discuss how to optimize the currently available treatments and highlight emerging treatments that may improve treatment efficacy in the future. [ABSTRACT FROM AUTHOR]

Vitiligo is a common autoimmune disease that progressively destroys melanocytes in the skin, resulting in the appearance of patchy depigmentation. This disfiguring condition frequently affects the face and other visible areas of the body, which can be psychologically devastating. The onset of vitiligo often occurs in younger individuals and progresses for life, resulting in a heavy burden of disease and decreased quality of life. Presentation patterns of vitiligo vary, and recognition of these patterns provides both diagnostic and prognostic clues. Recent insights into disease pathogenesis offer a better understanding of the natural history of the disease, its associations, and potential for future treatments. The first article in this continuing medical education series outlines typical and atypical presentations of vitiligo, how they reflect disease activity, prognosis, and response to treatment. Finally, we discuss disease associations, risk factors, and our current understanding of disease pathogenesis. [ABSTRACT FROM AUTHOR]

Background:Idiopathic guttate hypomelanosis (IGH) is a common hypopigmentation affecting a large amount of older population. However, there is no standard treatment. Cryotherapy has been reported as an alternative therapy for years; nevertheless, there is no randomized controlled study to determine its efficacy. Objectives:To evaluate the efficacy and side effects of tip cryotherapy in IGH treatment. Material and methods:Total 101 lesions were included. Forty-three lesions were treated with cryotherapy and 58 lesions were assigned as control. A single session of tip cryotherapy was delivered and remained for 5 s. Colorimeter was used to measure lesional luminosity at baseline and then monthly until 4 months. Digital photographs were evaluated by two blinded dermatologists. In addition, patients’ assessments and side effects were assessed. Results:Mean luminosity scale gradually decreased from baseline. Also, the score of the treated lesions has been significantly lower than that of the control lesions since week 8 (p = .005). At the fourth month, dermatologists’ assessment revealed that 82.3% of the treated lesions comparing to only 2% of the control showed more than 75% improvement (p < .001). Burning sensation was the most common side effect. Conclusion:Tip cryotherapy appears to be an effective therapy with minimal adverse effect for IGH. [ABSTRACT FROM AUTHOR]