Phaeohyphomycosis caused by Alternaria infectoria presenting as multiple vegetating lesions in a renal transplant patient

Abstract

a b s t r a c tThe genus Alternaria is one of the most common black moulds and appears to be increasing as a causative agent of subcutaneous phaeohyphomycosis, particularly among immunosuppressed patients.A 53-year-old patient who had received a kidney transplant presented with multiple verrucous lesions on the distal extremities. Positive histopathology and cultures, in addition to rDNA ITS region sequencing, identified the fungal isolate as Alternaria infectoria. Oral itraconazole was administered for 10 months. A follow-up at 15 months demonstrated no signs of infection.Clinical manifestations of cutaneous alternariosis vary significantly and only a few cases have been described in the literature. Although optimal treatment options remain controversial, this case of phaeohyphomycosis was successfully treated with itraconazole monotherapy.© 2010 Revista Iberoamericana de Micología. Published by Elsevier España, S.L. All rights reserved.Feohifomicosis producida por Alternaria infectoria con presentación clínica de múltiples lesiones vegetantes en un paciente sometido a un trasplante renal r e s u m e n Las especies del género Alternaria son mohos ubicuos que se caracterizan por presentar colonias de color gris; parecen ser cada vez más frecuentes como agente causal de las feohifomicosis subcutáneas, en especial entre pacientes inmunocomprometidos. Un paciente de 53 años de edad, que se había sometido a un trasplante renal, consultó por presentar tumores verrugosos en el tercio distal de las extremidades. La histopatología y cultivo positivos, además de la secuenciación de la región de transcripción interna ITS del rDNA, permitieron la identificación del aislamiento fúngico como Alternaria infectoria. Se instauró tratamiento con itraconazol oral durante 10 meses y, a los 15 meses de seguimiento, se demostró la ausencia de signos de infección.Las manifestaciones clínicas de la alternariosis cutánea son muy variables y tan sólo se han descrito unos pocos casos en los que se presenta en forma de tumoraciones verrugosas. Aunque el tratamiento de elección sigue siendo motivo de controversia, el paciente presentado en este estudio fue tratado satisfactoriamente con itraconazol.

Clinical spectrum of phaeohyphomycosis in solid organ transplant recipients

“…Although it has been published that phaeohyphomycosis is more frequent in kidney transplant recipients,1, 4, 6, 7, 8, 10 we did not find a statistical difference between kidney and heart transplants in our series. This finding may be owing to the limited number of patients.…”

“…Regarding the specific immunosuppressant drug, it seems that calcineurin inhibitors such as tacrolimus are more associated with greater susceptibility to fungal infections, which later can become recurrent 1, 4, 5, 7. All of our patients were taking this medication.…”

“…Diagnosis of phaeohyphomycosis is complicated by its highly variable clinical presentation 1, 2, 3, 4, 5, 6, 7. In our patients, the diagnosis was based on clinical, microbiologic, and histopathologic studies.…”

“…The increase in the number of organ transplant recipients (OTRs), in conjunction with improvement in their long-term treatment, has led to an increase in the incidence of phaeohyphomycosis 1, 3, 4, 5, 6, 7. Phaeohyphomycosis has a wide range of clinical presentations, which are associated with the immune status of the host 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. We describe 7 cases of phaeohyphomycosis in OTRs, which clearly demonstrate that the clinical presentations can have profound variations and that treating this infection in this specific patient population can be challenging.…”

Characterization of Alternaria infectoria extracellular vesicles

“…In addition, the members of this genus have proven to be rare opportunistic agents that cause phaeohyphomycosis involving cutaneous or subcutaneous infections and characterized by the presence of dark-walled hyphae or yeast-like cells in affected tissues. Of note, the number of infections in immunocompromised patients is increasing, including infections caused by common species such as A. alternata and A. infectoria [4–6]. …”