A case of cutaneous ulcerative alternariosis: Rare association with diabetes mellitus and unusual failure of itraconazole treatment

Alternaria species are ubiquitous dematiaceous fungi that are increasingly recognized as pathogens in immunocompromised patients or those with significant underlying disease, but they are also pathogens in otherwise healthy hosts. We describe a case of dermal cutaneous ulcerative alternariosis in a frail 83-year-old patient with diet-controlled diabetes mellitus. Histological analysis revealed hyphal morphology in tissue sections that was initially confused with that of a zygomycetous fungus, and multiple positive culture results were necessary to identify the organism. Treatment with oral itraconazole and surgical debridement were ineffective; clinical improvement was achieved by means of treatment with intravenous amphotericin B lipid complex. We review the literature regarding the role of diabetes mellitus in cutaneous alternariosis and regarding the efficacy of treatment with itraconazole, which has been used very successfully. To our knowledge, this is only the second case report noting diabetes mellitus uncomplicated by steroid administration as a possible predisposing factor for cutaneous infection.