A population genetics analysis in clinical isolates of Sporothrix schenckii based on calmodulin and calcium/calmodulin-dependent kinase partial gene sequences.

Sporotrichosis is a subcutaneous mycosis that is caused by diverse species of Sporothrix. High levels of genetic diversity in Sporothrix isolates have been reported, but few population genetics analyses have been documented. To analyse the genetic variability and population genetics relations of Sporothrix schenckii Mexican clinical isolates and to compare them with other reported isolates. We studied the partial sequences of calmodulin and calcium/calmodulin-dependent kinase genes in 24 isolates; 22 from Mexico, one from Colombia, and one ATCC® 6331™; the latter was used as a positive control. In total, 24 isolates were analysed. Phylogenetic, haplotype and population genetic analyses were performed with 24 sequences obtained by us and 345 sequences obtained from GenBank. The frequency of S. schenckii sensu stricto was 81% in the 22 Mexican isolates, while the remaining 19% were Sporothrix globosa. Mexican S. schenckii sensu stricto had high genetic diversity and was related to isolates from South America. In contrast, S. globosa showed one haplotype related to isolates from Asia, Brazil, Spain and the USA. In S. schenckii sensu stricto, S. brasiliensis and S. globosa, haplotype polymorphism (θ) values were higher than the nucleotide diversity data (π). In addition, Tajima's D plus Fu and Li's tests analyses displayed negative values, suggesting directional selection and arguing against the model of neutral evolution in these populations. In addition, analyses showed that calcium/calmodulin-dependent kinase was a suitable genetic marker to discriminate between common Sporothrix species.

Etiology of cutaneous vasculitis: utility of a systemic approach / Etiología de las vasculitis cutáneas: utilidad de una aproximación sistémica.

Cutaneous vasculities (CV) represents a diagnostic challenge, occurs as primary cutaneous disorder or as a manifestation of other entities. Objective: To search the cause of CV. Methods: Patients with CV were prospectively evaluated. In all patients, skin biopsies were drawn, and direct immunofluorescence was done in most of the patients. American College of Rheumatology (ACR) and Chapel Hill Consensus Conference Criteria (CHCC) were used for classification. Results: 32 patients were studied. There was female predominance (71.8%). Children presented drug-associated CV or Schönlein-Henoch púrpura (SHP). Adults presented more frequently SHP, systemic lupus erythematosus or paraneoplastic vasculitis, other diagnosis as polyarteritis nodosa, microscopic polyangiitis, thrombotic vasculitis (post-puerperal), antiphospholipid syndrome, Churg-Strauss syndrome, and drug-associated CV were presented. Using the ACR and CHCC criteria, 50% of cases were classified. Discussion: In our institution, during this work the etiologic diagnostic of CV increased more than twice. However, in the case of HSV or LA and SHP none of the proposed criteria had high specificity; other parameters were used to discern between both. Six patients remained as not classified. In our view, cryoglobulins and hepatitis serology do not seem useful unless patient's history supports they need to be done. Unclassified patients were followed-up closely for 2 years.

Las vasculitis cutáneas (VC), primarias o como manifestación de enfermedades sistémicas, constituyen un reto diagnóstico. Objetivo: Determinar las causas de VC. Métodos: Se incluyeron pacientes con diagnóstico de CV, a los cuales se les realizó valoración clínica, biopsia cutánea y exámenes de laboratorio. En la mayoría de los casos se realizó inmunofluorescencia directa. Los casos se clasificaron con los criterios del American College of Rheumatology (ACR) y la Chapel Hill Consensus Conference (CHCC). Resultados: Se incluyeron 32 pacientes; la frecuencia fue mayor en mujeres (71.8%). Los niños presentaron VC asociadas a medicamentos o púrpura de Schönlein-Henoch (PSH). En adultos se reportó con más frecuencia PSH, vasculitis asociada a lupus eritematoso sistémico y vasculitis paraneoplásicas; otros diagnósticos etiológicos incluyeron poliarteritis nodosa (PAN), poliangeítis microscópica (PAM), vasculitis trombótica (pospuerperal), síndrome antifosfolípidos (SAF), síndrome de Churg-Strauss (SCS) y VC asociada a medicamentos. Utilizando los criterios del ACR y la CHCC para vasculitis se clasificó el 50% de los casos. Discusión: En el Hospital Gea, durante este trabajo, el diagnóstico etiológico de las CV se incrementó más del doble. Sin embargo, en relación a los diagnósticos vasculitis por hipersensibilidad (VHS) y PSH ninguna de las clasificaciones utilizadas contaba con criterios específicos. Seis pacientes permanecieron sin clasificar. Observamos que los estudios de crioglobulinas y serología para hepatitis no son útiles como estudios iniciales, salvo que la historia clínica del paciente lo sugiera. Los pacientes sin clasificar se siguieron por dos años.

Eumicetoma: actualidades y perspectivas.

The eumycetoma is a severely debilitating chronic progressive fungal cutaneous infection. Classic clinical triad is characterized by painless subcutaneous mass, sinus tracts formation and sero-purulent discharge that contain aggregates of fungal hyphae called grains. Any part of the body can have affected, with extension to muscular or bone, even visceral compromised. The eumycetoma is observed in tropical and subtropical countries; In Latin-America, is reported with less frequency. In endemic areas, antibody presence again etiological agents were higher compared with number of people affected, thus it is supposed that individual genetic susceptibility most by exist. Recently, it was reported specific polymorphism in genes CR1, IL-8, NOS2 and chitriosidase, which were associated with development of eumycetoma. The diagnosis is suggested by clinical presentation; the histopathology and microbiology studies, plus radiologic valuation confirmed diagnosis. Madurella mycetomatis is the most informed etiological agent. Using phylogenetic tools new species in genus Madurella were reported; moreover, Trematosphaeria grisea and Pseudallescheria boydii were reclassified. Etiological agent Identification is important, because differences in antifungal susceptibility exist. Eumycetoma treatment includes surgery plus antifungal drugs. Identification of etiological agents is primordial, because antifungal resistance could exist. To development new pharmacological strategies, comprehension of grain formation physiology and drugs effects are necessary.

Update of phylogenetic and genetic diversity of Sporothrix schenckii sensu lato.

Sporothrix schenckii sensu lato causes subcutaneous mycosis. In this article we analysed its phylogeny and genetic diversity using calmodulin DNA sequences deposited in GenBank database. Population genetics indices were calculated, plus phylogenetic and haplotype network trees were built. Five clades with high values of posterior probability, 47 haplotypes and high diversity in the complex were found. Analysis of partial calmodulin sequences alignment revealed conserved and polymorphic regions that could be used as reference for taxonomic identification. The use of population genetics analysis allowed understanding the phylogenetic proximity of S. schenckii s. str. and S. brasiliensis; scarce genetic flow among them with low migration index and high ancestry coefficient was found. Similarly, S. globosa, S. mexicana and S. pallida sequences showed highly differentiated species with no genetic exchange. The phylogenetic tree suggests that S. mexicana shared a common ancestor with S. pallida; while S. globosa and S. brasiliensis are more related to S. schenckii s. str. and showed less haplotype diversity and restrictions in geographic distribution. In the haplotype network tree S. schenckii s. str. species displayed worldwide distribution without dispersion centres; while S. brasiliensis and S. globosa, exhibited Brazil and Euro-Asia as dispersion centres, respectively. Our data suggest that S. schenckii complex has been submitted to a divergent evolution process, probably due to the pressure of the environment and of the host. In contrast, S. brasiliensis could have been submitted to purifying selection or expansion process.

[HLA class II in Mexican patients with pemphigus vulgaris: shared epitope for autoimmunity]. / HLA clase II en pacientes mexicanos con pénfigo vulgar: epítopo compartido para autoinmunidad.

INTRODUCTION: Pemphigus is an autoimmune blistering disease of skin and mucous membranes characterized by presence of IgG antibodies against desmoglein 3, and 1. Desmoglein 3 and 1 are presented in pemphigus vulgaris and pemphigus foliaceous, respectively. Desmoglein are transmembrane proteins that form part of cellular junctions called desmosomes. Major histocompatibility complex class II molecules have been related to autoimmune disease; in pemphigus vulgaris, different human lymphocyte antigens (HLA) were associated among different ethnic groups, such as HLA-DR4, HLA-DR14, and HLA-DR1. OBJECTIVE: to determine the allele HLA-DR genetic frequencies in Mexican patients with pemphigus. METHOD: Patients with clinical, histological, and immunofluorescence diagnosis monitored at the Dermatology Department of the Mexican General Hospital were included. DNA was extracted from blood samples and genetic recognition of HLA-DRß1 was performed by polymerase chain reaction and hybridization. Forty-three patients with pemphigus were included: 35 (81.4%) women and eight men (18.6%) between 16 and 85 years old. RESULTS: The HLA-DR14 and HLA-DR1 genetic frequencies were elevated among pemphigus patients and these alleles confer risk to pemphigus 2.2 and 3.3, respectively. CONCLUSION: These findings suggest that pemphigus vulgaris susceptibility is part of a general predisposition to present autoimmune diseases.

[Presence of lactoferrin (LF) in lymphocutaneous sporotrichosis. Yeast-bound antimicrobial peptide]. / Presencia de lactoferrina (LF) en la esporotricosis linfocutánea. Péptido antimicrobiano unido a levaduras.

Sporotrichosis is a common subcutaneous mycosis in Latin America, produced by dimorphic fungi belong to Sporothrix schenckii complex of cryptic species. Infection is acquired by traumatic inoculation with contaminated organic material. Host immune response includes polymorphonuclear neutrophils chemotaxis and release of granular components. Lactoferrin is a protein member of the transferrin family of iron-binding proteins, present inside polymorphonuclear granular structure, and has been reported to affect growth and development of infectious agents, including fungal organisms. Nevertheless, lactoferrin expression in sporotrichosis infections has not been reported yet. OBJECTIVE: To determine the expression of lactoferrin using immunohistochemical staining in sporotrichosis human infection. MATERIAL AND METHODS: The dermatology department's files during a period of five years were reviewed; cases with a diagnosis of sporotrichosis were selected and lactoferrin immunostaining was performed when enough biological material was available. RESULTS: Three cases with a diagnosis of sporotrichosis and adequate biological material on paraffin block were identified. In all cases, lactoferrin immunostaining was positive around yeast cell.

Trypanosoma cruzi DTU II coinfection with bacteria producing prolonged cutaneous lesion in a healthy young male.

Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi and is genetically classified in six discrete typing units (DTUs). The isolates reported in Mexico are generally associated with DTU I. We presented a case of a prolonged cutaneous lesion in a Mexican man, caused by DTU II in coinfection with Bacillus velezensis and Corynebacterium sp. The patient assessment included a complete clinical history, physical exam, laboratory tests, and a skin biopsy. In the facial tissues, intracellular parasites were revealed. The PCR tests were positive for T. cruzi in tissue and blood samples. DNA satellite sequencing was correlated with the DTU II. The initial serological tests reported negative results. However, four months later, two serological tests reported positive results. These exams were performed in different health centers. Mexico is considered an endemic area for CD; nevertheless, this is just the second cutaneous case associated with a DTU different from DTU-I noted in this country. From an ecological point of view, this fact suggests a geographical expansion of DTU II and an association with atypical skin manifestations. Further studies should be conducted to understand this exciting association between DTU-II and prolonged cutaneous expression in humans.

Human leukocyte antigen Class II alleles associated with acral lentiginous melanoma in Mexican Mestizo patients: A case-control study.

Background Melanoma is an aggressive cutaneous cancer. Acral lentiginous melanoma is a melanoma subtype arising on palms, soles, and nail-units. The incidence, prevalence and prognosis differ among populations. The link between expression of major histocompatibility complex Class II alleles and melanoma progression is known. However, available studies report variable results regarding the association of melanoma with specific HLA Class II loci. Aims The aim of the study was to determine HLA Class II allele frequencies in acral lentiginous melanoma patients and healthy Mexican Mestizo individuals. Methods Eighteen patients with acral lentiginous melanoma and 99 healthy controls were recruited. HLA Class II typing was performed based on the sequence-specific oligonucleotide method. Results Three alleles were associated with increased susceptibility to develop acral lentiginous melanoma, namely: HLA-DRB1*13:01; pC = 0.02, odds ratio = 6.1, IC95% = 1.4-25.5, HLA-DQA1*01:03; pC = 0.001, odds ratio = 9.3, IC95% = 2.7-31.3 and HLA-DQB1*02:02; pC = 0.01, odds ratio = 3.7, IC95% = 1.4-10.3. Limitations The small sample size was a major limitation, although it included all acral lentiginous melanoma patients seen at the dermatology department of Dr. Manuel Gea González General Hospital during the study period. Conclusion HLA-DRB1*13:01, HLA-DQB1*02:02 and HLA-DQA*01:03 alleles are associated with increased susceptibility to develop acral lentiginous melanoma in Mexican Mestizo patients.

Utility of IgG4 immunohistochemistry detection in pemphigus diagnosis.

Pemphigus includes a group of blistering autoimmune diseases that affect the skin and mucosa, characterized by the formation of epidermal bullous and the presence of antibodies against binding proteins. Pemphigus is classified according to clinical presentation, target molecule, and IgG production as pemphigus vulgaris, foliaceous, IgA-pemphigus, and paraneoplastic pemphigus. Thus, the identification of autoantibodies class and site of deposition is mandatory. The gold standard to identify the immune complex deposition is the direct immunofluorescences technique, performed in fresh tissue; unfortunately, this method is unavailable in the regional hospital at the Mexican provinces. Nevertheless, IgG subclass-4 is the prevalence of immunoglobulin in acantholysis. Therefore, this IgG subclass could be detected using IgG4 immunohistochemistry. Because direct immunofluorescences technique is absent in provinces or patients denied a new biopsy to confirm the diagnosis, this work presented pemphigus vulgaris confirmation using the IgG4 immunohistochemistry technique in patients with clinical lesions suggestive of pemphigus vulgaris and intraepidermal blister manifestation in histopathology.

Cutaneous manifestations of COVID-19 in Mexican patients: A case series and review of literature.

China officially recognized atypical pneumonia outbreak in December 2019; on 11 March 2020, the World Health Organization declared COVID-19 as a pandemic that is produced by a new coronavirus, named SARS-CoV-2, of rapid transmissibility, which can be asymptomatic, with mild to severe respiratory symptoms, and with cardiovascular, neurological, gastrointestinal, and cutaneous complications. Considering that the pandemic prolonged more than initially expected was prognostic, it is essential for the medical community to identify the signs and symptoms of COVID-19. Thus, this work's objectives were to present cases of cutaneous lesions observed in COVID-19 Mexican patients. We register cutaneous lesions in COVID-19 patients referred from internal medicine and otorhinolaryngology services to dermatology. We presented four interesting cases with cutaneous lesions, including exanthema morbilliform, urticaria, chilblains, ecchymosis, and facial edema, and review the available literature. The most frequent cutaneous markers are rash, chilblains, and urticaria. Skin lesions may be the first manifestation of COVID-19, accompany initial respiratory symptoms, or appear during the disease course. Symptoms associated with vascular changes (livedo reticularis and vasculitis) are considered of poor prognosis.

Trypanosoma cruzi infection associated with atypical clinical manifestation during the acute phase of the Chagas disease.

BACKGROUND: Chagas disease (CD) is caused by the protozoan parasite Trypanosoma cruzi and is transmitted by triatomine insects. Clinical manifestations vary according to the phase of the disease. Cutaneous manifestations are usually observed in the acute phase (chagoma and Romaña's sign) or after reactivation of the chronic phase by immunosuppression; however, a disseminated infection in the acute phase without immunosuppression has not been reported for CD. Here, we report an unusual case of disseminated cutaneous infection during the acute phase of CD in a Mexican woman. METHODS: Evaluation of the patient included a complete clinical history, a physical exam, and an exhaustive evaluation by laboratory tests, including ELISA, Western blot and PCR. RESULTS: Skin biopsies of a 50-year-old female revealed intracellular parasites affecting the lower extremities with lymphangitic spread in both legs. The PCR tests evaluated biopsy samples obtained from the lesions and blood samples, which showed a positive diagnosis for T. cruzi. Partial sequencing of the small subunit ribosomal DNA correlated with the genetic variant DTU II; however, serological tests were negative. CONCLUSIONS: We present a case of CD with disseminated skin lesions that was detected by PCR and showed negative serological results. In Mexico, an endemic CD area, there are no records of this type of manifestation, which demonstrates the ability of the parasite to initiate and maintain infections in atypical tissues .

Trypanosoma cruzi DTU II coinfection with bacteria producing prolonged cutaneous lesion in a healthy young male

ABSTRACT Chagas disease (CD) is a neglected tropical disease caused by Trypanosoma cruzi and is genetically classified in six discrete typing units (DTUs). The isolates reported in Mexico are generally associated with DTU I. We presented a case of a prolonged cutaneous lesion in a Mexican man, caused by DTU II in coinfection with Bacillus velezensis and Corynebacterium sp. The patient assessment included a complete clinical history, physical exam, laboratory tests, and a skin biopsy. In the facial tissues, intracellular parasites were revealed. The PCR tests were positive for T. cruzi in tissue and blood samples. DNA satellite sequencing was correlated with the DTU II. The initial serological tests reported negative results. However, four months later, two serological tests reported positive results. These exams were performed in different health centers. Mexico is considered an endemic area for CD; nevertheless, this is just the second cutaneous case associated with a DTU different from DTU-I noted in this country. From an ecological point of view, this fact suggests a geographical expansion of DTU II and an association with atypical skin manifestations. Further studies should be conducted to understand this exciting association between DTU-II and prolonged cutaneous expression in humans.

[Giant gravidarum granuloma of the scalp]. / Granuloma gravidarum gigante en piel cabelluda.

Lobular capillary hemangioma (pyogenic granuloma) has been reported more frequently in the skin (88%) than in the mucous membranes (12%). Granuloma gravidarum is a pyogenic granuloma that develops during pregnancy, often in the oral mucosa. Estrogens apparently increase the inflammatory response of mucous membranes. In this article, we describe the first case of a granuloma gravidarum of the scalp.

Suitability of internal transcribed spacers (ITS) as markers for the population genetic structure of Blastocystis spp.

BACKGROUND: The purpose of this study was to assess the genetic variation and differentiation of Blastocystis subtypes (STs) recovered from symptomatic children by analysing partial sequences of the small subunit rDNA gene region (SSUrDNA) and internal transcribed spacers (1 and 2) plus the 5.8S region (ITS, ITS1 + 5.8S + ITS2) and comparing with isolates from other countries. FINDINGS: Faecal samples from 47 Blastocystis-infected children with gastrointestinal symptoms and negative for pathogenic enterobacteria were analysed. PCR was performed on DNA from all the samples to identify Blastocystis STs, amplifying a fragment of SSUrDNA and the ITS region. The amplicons were purified and sequenced, and consensus sequences were submitted to GenBank; afterwards, SSUrDNA sequences were analysed for genetic diversity according to geographic area. Regarding the Blastocystis STs found, 51% were ST1, 23% ST2, 19% ST3 and 2% ST7. For ITS, a haplotype network tree and Bayesian inference revealed the presence of two novel variants of ST1, clustering some sequences into ST1A and ST1B. The values of nucleotide diversity (π) and haplotype polymorphism (θ) for ST1, ST2 and ST3 ranged from 0 to 1, whereas the ratio of genetic differentiation (FST)/migration index (Nm) showed the highest differentiation between Libya and Thailand-Philippines for ST2 (0.282/0.63). In contrast, a high flow gene was observed between Czech Republic-Denmark-Holland-Spain and USA-Mexico-Colombia for ST1 (0.003/84). CONCLUSION: Our data on genetic differentiation and gene flow might explain the differences for the prevalence of Blastocystis STs. Moreover, the ITS region could be used as a genetic marker to assess genetic variation in this parasite.

Proliferating trichilemmal cyst: the value of ki67 immunostaining.

BACKGROUND: A proliferating trichilemmal cyst (PTC) is an uncommon, rapidly-reproducing cutaneous epithelial cyst, differentiating from the isthmic portion of the outer hair root sheath. It is usually described as a benign tumor, but malignant transformation has been reported and is then denominated as a malignant proliferating trichilemmal tumor. Ki67 immunostaining has been used as a methodology for the evaluation of tumor grade in other tumors, due to its distinctive reaction patterns which exclusively involve proliferating cells. OBJECTIVES: (1) To report the incidence of cases of PTCs in a General Hospital during a 12 years period. (2) To determine the expression of ki67 using immunohistochemical staining. (3) To correlate ki67 reaction patterns with clinical prognosis. MATERIALS AND METHODS: The dermatology department's files during a period of 12 years were reviewed; cases with a diagnosis of PTC were selected, and ki67 immunostaining was done when enough biological material was available. RESULTS: A total of 15 cases with a diagnosis of PTC were identified. In 12 cases, ki67 immunostaining was carried out. In 9 of the 12 cases, ki67 was observed in the basal cells of the cystic epithelium, one case was moderately positive in palisading epithelial cells; in the other two cases ki67 immunostaining was negative. Clinical follow-up was done and revealed that no patient had local recurrence in 5 years after surgical removal of PTC. We therefore consider this immunostaining technique is probably correlated with low recurrence potential.

Granuloma gravidarum gigante en piel cabelluda / Giant gravidarum granuloma of the scalp

El hemangioma capilar lobular (granuloma piógeno) ha sido informado con más frecuencia en piel (88%) que en mucosas (12%). El granuloma gravidarum es un granuloma piógeno que se presenta frecuentemente durante el embarazo a nivel de mucosa oral. Ha sido asociado con la acción de los estrógenos y una respuesta inflamatoria exagerada de las mucosas. En este artículo informamos el primer caso de granuloma gravidarum en piel cabelluda.

Lobular capillary hemangioma (pyogenic granuloma) has been reported more frequently in the skin (88%) than in the mucous membranes (12%). Granuloma gravidarum is a pyogenic granuloma that develops during pregnancy, often in the oral mucosa. Estrogens apparently increase the inflammatory response of mucous membranes. In this article, we describe the first case of a granuloma gravidarum of the scalp.