Clinical and Treatment Aspects of Brown–Black Fungi

Cytological clues to Alternaria alternata

Alternaria alternata is dematiaceous fungi affecting mainly immunocompromised host. It generally causes cutaneous infection in humans, but can cause fatal disease. Fine needle aspiration cytology (FNAC) has not been used widely for the diagnosis of dematiaceous fungi. Here, we present a case of Alternaria alternata in an immunocompetent patient diagnosed on cytology and culture.

Black yeasts-like fungi isolated from dialysis water in hemodialysis units

Hemodialysis in patients with chronic renal failure promotes the removal of toxic substances, water, and minerals from the body and often takes place in specialized clinics. Microbial contamination of dialysis fluid is a serious problem in therapy. One of the sources of contamination is the water used to prepare the dialysate. In Brazil, legislation regulating the microbiological quality of water for dialysis does not cover waterborne microbes such as Pseudomonas, mycobacteria, and fungi. The aim of the present study was to quantify, isolate, and identify fungi present in water systems in six hemodialysis units in Curitiba, Paraná state, Brazil. Fungi were analyzed by surface plating and membrane filtration. Isolates were identified by morphology, while the dematiaceous fungi were identified by sequencing the rDNA ITS region. It was found that 66 % of the samples presented fungi, while black fungi were present in 46 % of all samples. Twenty-eight isolates from treated water for dialysis and dialysate were identified by sequencing and were found to be Exophiala pisciphila, E. cancerae, E. equina, and Rhinocladiella similis. The presence of dematiaceous fungi may pose a risk for debilitated hospitalized patients.

Cutaneous Phaeohyphomycosis Caused by Alternaria alternata Unresponsive to Itraconazole Treatment

Cutaneous alternariosis is an opportunistic infection that has been described mainly in patients treated with corticosteroids. We report a case of dermal alternariosis occurring in a woman treated with corticosteroids after a neurosurgery that was unresponsive to itraconazole. Treatment with intravenous voriconazole was initiated, followed by oral protocol, with marked improvement of the lesions.

Cutaneous phaeohyphomycosis caused by Exophiala spinifera in a patient with systemic lupus erythematosus

Exophiala spinifera can induce both phaeohyphomycosis and chromomycosis. To date there have been 18 human infections caused by E. spinifera in the English literature. A case of E. spinifera-induced phaeohyphomycosis in a patient with systemic lupus erythematosus (SLE) is described. Direct microscopic examination of the pus showed branched, septate and chained hyphae and spores. A dark green velvety colony grew on Sabouraud dextrose agar. Slide culture showed branched, septate hyphae and spine-like annellated conidiophores. Histopathological biopsy revealed yellowish brown hyphae and spores. The isolate was identified as E. spinifera by DNA sequence analysis. The strain was unable to liquefy gelatin, grew at 25°C to 39°C, and was sensitive to itraconazole, amphotericin B, and terbinafine. To our knowledge, this is the first case of cutaneous phaeohyphomycosis caused by E. spinifera in SLE patients.