Association between the skin microbiome and lichen striatus hypopigmentation: Cutibacterium acnes as a potential cause.

BACKGROUND: Lichen striatus (LS) is an acquired skin disorder with a linear pattern along Blaschko's lines. It commonly occurs in childhood, and the lesions spontaneously regress within several months. OBJECTIVES: Although up to 50% of LS cases exhibit hypopigmentation that can persist for several months to years, it is unknown why LS is associated with such a high incidence of hypopigmentation compared to other inflammatory skin diseases. Therefore, this study aimed to analyse the differences in the skin microbiome between LS patients with and without hypopigmentation. METHODS: Differences in skin microbiome were analysed using whole genome sequencing of skin biopsies and subsequent bioinformatics analyses. RESULTS: Some microbes commonly found in hypopigmented skin disorders, including Cutibacterium acnes, were more abundant in patients with LS showing hypopigmentation than in those not showing hypopigmentation. CONCLUSIONS: The skin microbiota may be involved in the development of hypopigmentation in LS and may be considered a treatment target to reduce LS duration and hypopigmentation.

Comparative efficacy of topical application of tacrolimus and clotrimazole in the treatment of pityriasis versicolor: A single blind, randomised clinical trial.

BACKGROUND: Pityriasis versicolor (PV) is a common superficial fungal disease. Possibility of emergence of resistant strains to azoles, and difficulty in differentiation of hypopigmented PV and early vitiligo, encouraged us to evaluate the efficacy of topical tacrolimus (a calcineurin inhibitor agent with proven in vitro anti-Malassezia effect) for PV treatment generally and its effect on PV-induced hypopigmentation specifically. OBJECTIVES: To evaluate the efficacy of topical tacrolimus on pityriasis versicolor. PATIENTS/METHODS: Fifty PV patients were randomly allocated into two equal groups applying either topical clotrimazol or tacrolimus twice daily for 3 weeks. They were evaluated at the beginning of study, in the third and fifth weeks clinically and mycologically (direct smear). RESULTS: Although both treatments resulted in global, clinical, and mycological cure of PV, there was no significant difference regarding the mentioned aspects of cure between tacrolimus and clotrimazole treated patients. (P-value: .63, .45, and .26, respectively) Tacrolimus had no significant effect on hypopigmentation in the fifth week follow-up. (P-value: .62). CONCLUSIONS: In spite of the lack of efficacy of tacrolimus on PV-induced hypopigmentation, the therapeutic effect on PV introduces tacrolimus as a therapeutic option for PV, especially when early vitiligo is among the differential diagnoses without concerning the aggravating effect of topical corticosteroids on PV.

Strains of the Propionibacterium acnes type III lineage are associated with the skin condition progressive macular hypomelanosis.

Progressive macular hypomelanosis (PMH) is a common skin disorder that causes hypopigmentation in a variety of skin types. Although the underlying aetiology of this condition is unclear, there is circumstantial evidence that links the skin bacterium Propionibacterium acnes to the condition. We now describe the first detailed population genetic analysis of P. acnes isolates recovered from paired lesional and non-lesional skin of PMH patients. Our results demonstrate a strong statistical association between strains from the type III phylogenetic lineage and PMH lesions (P = 0.0019), but not those representing other phylogroups, including those associated with acne (type IA1). We also demonstrate, based on in silico 16S rDNA analysis, that PMH isolates previously recovered from patients in Europe are also consistent with the type III lineage. Using comparative genome analysis, we identified multiple genomic regions that are specific for, or absent from, type III strains compared to other phylogroups. In the former case, these include open reading frames with putative functions in metabolism, transport and transcriptional regulation, as well as predicted proteins of unknown function. Further study of these genomic elements, along with transcriptional and functional analyses, may help to explain why type III strains are associated with PMH.

Propionibacterium acnes and the pathogenesis of progressive macular hypomelanosis.

BACKGROUND: Progressive macular hypomelanosis is a common hypopigmentation mainly on the central parts of the trunk, predominantly in young adults, especially women. It is often mistaken for pityriasis versicolor and pityriasis alba. It occurs in all races and has been described in many parts of the world. We discovered follicular red fluorescence restricted to lesional skin. We suspected a relation with a porphyrin-producing bacteria residing in sebum of the pilosebaceous duct, and we therefore performed a study in 8 patients. Observation In all biopsy specimens taken from lesional skin of 8 women, we could demonstrate gram-positive bacteria in the pilosebaceous duct, and a mild perifollicular lymphocytic infiltrate was seen. In all but 1 patient, Propionibacterium acnes was yielded from cultured biopsy specimens taken from follicular lesional skin. Healthy follicular skin did not show bacteria in histological sections, and cultures did not yield anaerobic bacteria. CONCLUSIONS: There seems to be a relation between the presence of P acnes and the hypopigmented macules. We propose that a factor is produced by these strains of P acnes, which interfere with melanogenesis. Based on these observations, we are undertaking a clinical trial to find a treatment for this troubling, intractable disease.

Body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles, depigmentation of mouthparts, and presence of Batrachochytrium dendrobatidis are related.

A fungal pathogen Batrachochytrium dendrobatidis (Bd), which can cause morbidity and death of anurans, has affected amphibian populations on a worldwide basis. Availability of pure cultures of Bd isolates is essential for experimental studies to understand the ecology of this pathogen. We evaluated the relationships of body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles to depigmentation of mouthparts and determined if dekeratinization indicated an infection by Batrachochytrium dendrobatidis. A strong association existed for both species, one from South America (Brazil: São Paulo) and one from North America (USA: Maine). We believe it prudent not to kill adult amphibians if avoidable, thus obtaining tissue for isolating Bd from tadpoles is reasonable because infected specimens of some species can be selectively collected based on depigmentation of mouthparts.

[A white woman with white skin spots]. / Een blanke vrouw met lichte vlekken.

A 26-year-old white woman came to the clinic because of white spots. The spots were confluent in the midline, non-scaly and localized on trunk and proximal parts of the arms. Biopsy showed loss of pigment in the epidermis. The diagnosis was: progressive macular hypomelanosis.

Investigation of Propionibacterium acnes in progressive macular hypomelanosis using real-time PCR and culture.

BACKGROUND: Progressive macular hypomelanosis (PMH) is a dermatosis of unknown etiology. It has been concluded that it involves the presence of Propionibacterium acnes, a saprophyte of the pilosebaceous follicles. In our study, we investigated the presence of P. acnes in lesional and non-lesional skin of patients with PMH through quantitative real-time polymerase chain reaction (PCR) and bacterial culture from a skin fragment. MATERIALS AND METHODS: An observational, exploratory study, with laboratory comparison of lesional (study group) and non-lesional skin (comparison group), in patients with PMH, was carried out with 36 patients, seen in the dermatology outpatient setting at the Oswaldo Cruz University Hospital (OCUH), Recife, Pernambuco, Brazil, between March and May 2008. All patients were submitted to a Wood's lamp examination, mycological research, and biopsies of lesional and non-lesional skin from the back. Skin fragments were submitted to a histopathology test, bacterial culture, and a quantitative real-time PCR test. The program Statistical Package for Social Sciences, version 12.0, was employed for relationship analysis with the Wilcoxon and McNemar tests. RESULTS: There was a significant predominance of P. acnes on lesional skin, in comparison to non-lesional skin (P<0.001), as demonstrated by culture and quantitative real-time PCR. CONCLUSION: Although P. acnes is a saprophyte, the hypothesis may be raised that this microorganism participates in the development of PMH.

Body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles, depigmentation of mouthparts, and presence of Batrachochytrium dendrobatidis are related / Tamanho do corpo, despigmentação das partes bucais e presença de Batrachochytrium dendrobatidis estão relacionados em Hylodes cf. ornatus e Lithobates catesbeianus

A fungal pathogen Batrachochytrium dendrobatidis (Bd), which can cause morbidity and death of anurans, has affected amphibian populations on a worldwide basis. Availability of pure cultures of Bd isolates is essential for experimental studies to understand the ecology of this pathogen. We evaluated the relationships of body length of Hylodes cf. ornatus and Lithobates catesbeianus tadpoles to depigmentation of mouthparts and determined if dekeratinization indicated an infection by Batrachochytrium dendrobatidis. A strong association existed for both species, one from South America (Brazil: São Paulo) and one from North America (USA: Maine). We believe it prudent not to kill adult amphibians if avoidable, thus obtaining tissue for isolating Bd from tadpoles is reasonable because infected specimens of some species can be selectively collected based on depigmentation of mouthparts.

O fungo patógeno Batrachochytrium dendrobatidis (Bd) é apontado como o causador de morbidade e morte em anuros, e tem afetado populações de anfíbios em uma base mundial. Avaliar culturas puras de isolados de Bd é essencial para estudos experimentais para o entendimento da ecologia desse patógeno. Avaliou-se a relação entre o comprimento do corpo em girinos de Hylodes cf. ornatus e Lithobates catesbeianus com a despigmentação das peças bucais, para verificar se a desqueratinização indica uma infecção por Batrachochytrium dendrobatidis. Uma forte associação existe para ambas as espécies, uma da América do Sul (Brasil: São Paulo) e uma da América do Norte (USA: Maine). Acredita-se ser prudente este uso, para evitar a morte de anfíbios adultos; dessa forma, obter tecidos para isolar o Bd de girinos é razoável, porque espécimes infectados podem ser coletados seletivamente com base na despigmentação do aparelho bucal.

Clinical manifestations, diagnosis and classification of leprosy.

Mycobacterium leprae, the causative organism of leprosy is slow-growing and the reason is its long incubation period of 2-4 years. Males are predominantly affected and deformity is produced in less than 2% of people affected with the disease. The disease manifests in the skin as macules, papules, nodules, plaques or infiltration. Hypopigmented or erythematous skin patches with definite sensory deficit is one of the clinical cardinal signs by which one can make a definite diagnosis. Demonstration of bacilli in the slit skin smear is the bacteriological cardinal sign used to make definite diagnosis of leprosy. Involvement of common cutaneous nerves with thickening and/or tenderness with its dysfunction is the second clinical cardinal sign used to diagnose leprosy. Diagnosis can be made by eliciting definite sensory deficit in the skin lesions (other than nodules and infiltration). In the absence of two clinical cardinal signs and when there is a strong suspicion of leprosy, slit skin smear should be taken from both ear lobes and one of the lesions for demonstration of acid-test bacilli. Clinical classification is based on characteristics like number of lesions, their margin, sensory deficit, satellite lesions, symmetry of lesions, central healing and scaling. Up to 5 lesions are grouped under paucibacillary and six and more are grouped under multibacillary leprosy.