Abstract Trichosporon asahii is the causal agent of trichosporonosis. Patients with immunosuppression or hematological malignancies are at higher risk of infection. Skin and mucosal involvement appear as fast-growing papulonodular lesions and necrotic ulcers. Internal organ dissemination is lethal. Therapeutic success depends on the underlying disease. Here, the authors present the first case of disseminated mucocutaneous trichosporonosis in a patient with a post-mortem diagnosis of histiocytic sarcoma, a rare and aggressive haematolymphoid neoplasm. Regretfully, death occurred despite treatment with liposomal amphotericin B and supportive measures, showcasing the fatality of both diseases.

Abstract Cutaneous leishmaniasis (CL) involves several differential diagnoses as it lacks a gold standard diagnostic test. Its diagnosis is easier in endemic regions; however, many cases come from travelers to endemic areas. A 22-year-old patient, who had recently visited Oaxaca, Mexico, developed two asymptomatic ulcers weeks later on the left auricle and the nose. Leishmania mexicana was identified using polymerase chain reaction. The patient was treated with imiquimod 5% cream three times/week, providing favorable results after 12 weeks, without relapse 2 months after therapy. To our knowledge, this is the first case of CL due to L. mexicana effectively treated with imiquimod.

MALDI-TOF MS mass spectrometry is a rapid and straightforward technique to identify microorganisms by protein analysis. The study was performed in 304 yeast isolates from superficial and deep mycoses, in order to compare three methods: conventional (biochemical and morphological), MALDI-TOF MS, and polymerase chain reaction (PCR, reference). We included 24 species with predominance of Candida spp and Cryptococcus spp. The identification by conventional methods was 258/304 strains, while by MALDI-TOF MS was: 277/304 strains (84.8% versus 91.2%, P = not significant). The Kappa coefficient comparing MALDI-TOF-MS with PCR reported excellent concordance (0.99). The sensitivity and specificity of MALDI-TOF MS for the diagnosis of opportunistic pathogenic yeasts of clinical samples were 94.6% and 99% respectively. MALDI-TOF MS is a simple, fast and reliable tool for pathogenic yeasts.

Resumen La espectrometría de masas MALDI-TOF MS es una técnica rápida y sencilla para identificar microorganismos por análisis proteico. Se estudiaron 304 aislados de levaduras procedentes de micosis superficiales y profundas, con el objetivo de comparar tres métodos: convencional (bioquímico y morfológico), MALDI-TOF MS, y reacción en cadena de la polimerasa (RPC, método de referencia). Se estudiaron 24 especies con predominio de Candida spp y Cryptococcus spp. La identificación por método convencional fue de 258/304 cepas, mientras que por MALDI-TOF MS fue de: 277/304 cepas (84,8 versus 91,2%, p = no significativo). El coeficiente Kappa entre el MALDI-TOF MS y la RPC reportó una excelente concordancia (0,99). La sensibilidad y la especificidad de MALDI-TOF MS para la identificación de levaduras patógenas oportunistas de muestras clínicas fueron de 94,6% y 99%; respectivamente. MALDI-TOF MS demostró ser una herramienta de alta precisión para la identificación de levaduras patógenas.

Abstract: We report 73 cases of cutaneous sporotrichosis from the Community Dermatology program, at the central and mountain areas of the state of Guerrero, Mexico. A similar number of cases was found between children and adults, mostly peasants and school-age children with rural occupations. Upper limbs were the mostly affected and the predominant clinical form was lymphocutaneous (56.16%). All cultures corresponded to Sporothrix schenckii (sl). Treatment was done with potassium iodide in 54 patients, achieving clinical and mycological cure in all cases.

Sporotrichosis is the most common subcutaneous or implantation mycosis in Mexico. The case of a preauricular cutaneous-fixed sporotrichosis simulating atypical bacterial cellulitis is reported in an elderly patient with no history of trauma. The biopsy showed a suppurative granuloma with scarce yeast. Sporothrix schenckii was identified in the culture and confirmed by molecular biology. She was treated with itraconazole and a clinical and mycological cure was obtained. The case of atypical presentation is presented, coming from a semi-arid zone with extreme weather.

Resumen La esporotricosis es la micosis subcutánea o por implantación más frecuente en México. Se comunica el caso de una esporotricosis cutánea-fija preauricular que simuló una celulitis bacteriana atípica, en una paciente anciana sin antecedente de traumatismo. La biopsia mostró un granuloma supurativo con presencia de levaduras escasas. En el cultivo se identificó Sporothrix schenckii que se confirmó por biología molecular. Se trató con itraconazol obteniéndose una curación clínica y micológica. Se presenta el caso de presentación atípica, proveniente de una zona semidesértica con clima extremo.

Trichomycosis is a superficial infection caused by Corynebacterium flavescens, which regularly affects axillary, and to a a lesser extent, pubic, scrotal and intergluteal, and exceptionally, head hairs or trichomycosis capitis (TC). This condition is characterised by the formation of bacterial nodules. Clinically, it can be confused with white piedra or pediculosis. The diagnosis is made by microscopic and dermoscopic observation and confirmed by culture. Objective: To present a case of TC in an infant and illustrate the microscopic, dermoscopic, and ultrastructural characteristics. Clinical case: A 6 month-old boy, otherwise healthy, with multiple yellowish concretions on the hairs of the head. TC was confirmed by yellow fluorescence with Wood’s light; white-yellowish beads, like “rosaries of crystalline stones’’ were observed on dermoscopy, direct examination showed bacterial masses, and Corynebacterium flavescens was identified by culture. A superficial infection, without perforation of the hairs, was confirmed by electron microscopy. Treatment with fusidic acid for 3 weeks achieved a clinical and microbiological cure. Conclusion: TC is a rare condition that affects children, and tends to be mistaken for other diseases of the hair, such as pediculosis and mycotic infections.

La tricomicosis es una infección superficial causada por Corynebacterium flavescens, que afecta por lo regular pelos axilares, en menor grado los púbicos, los escrotales e interglúteos y excepcionalmente los de la cabeza o tricomicosis capitis (TC). Esta infección se caracteriza por formación de nódulos pilosos. Clínicamente se confunde con infecciones como piedra blanca y pediculosis. El diagnóstico se realiza por microscopia y dermatoscopia de masas bacterianas y confirmado por cultivo. Objetivo: Presentar un caso de TC en un infante, y mostrar las características microscópicas, dermatoscópicas y ultraestructurales. Caso clínico: Niño sano de 6 meses de edad, con dermatosis que afectó los pelos de la cabeza en forma de múltiples nódulos-pilosos amarillentos. Se comprobó TC mediante fluorescencia amarilla a la luz de Wood; a la dermatoscopia se observaron cadenas blanco-amarillentas, como “rosarios de piedras cristalinas”; al examen directo se distinguieron masas bacterianas y al cultivo se identificó Corynebacterium flavescens. A la microscopia electrónica se observó infección superficial, sin perforación de los pelos. Se realizó tratamiento con aplicación de ácido fusídico por 3 semanas y se obtuvo curación clínica y microbiológica. Conclusión: La TC es una entidad rara que se presenta en niños, y que suele confundirse con otros padecimientos del pelo como la pediculosis e infecciones micóticas.

ABSTRACT Mycetoma is a chronic granulomatous disease, classified into eumycetoma caused by fungi and actinomycetoma due to aerobic filamentous actinomycetes. Mycetoma can be found in geographic areas near the Tropic of Cancer. Mexico is one of the countries in which actinomycetoma is endemic. We report an extraordinary case of an adult male with double eumycetoma caused by Madurella mycetomatis and Fusarium verticillioides on both feet.