Cutaneous infections by dematiaceous opportunistic fungi: Diagnosis and management in 11 solid organ transplant recipients

Abstract

A clinical, histopathological and microbiological correlation is essential to corroborate this diagnosis. Solitary lesions are easily treated with surgery, but larger or multiple lesions may require long medical treatments combined with surgery and modification of immunosuppressive medication. The list of dematiaceous fungi implicated in cutaneous infections is expanding, in line with the availability of more sophisticated identification methods and the increasing number of immunosuppressed patients.

Polyphasic identification of three new species in Alternaria section Infectoriae causing human cutaneous infection

“…Given that no optimal treatment has been defined for Alternaria infections, several therapeutic options are used, depending on the status of the patient concerned and the extent of disease. The most commonly antifungal therapy includes ITC, VRC and PSC, being the former widely used in cutaneous alternariosis and usually combined with surgical excision of involved tissue and reduction of the immunosuppression in cases of transplant recipients . In our case, in the first patient the infection was resolved with surgical excision of the nodule and topical VRC; the second patient with multiple skin lesions was initially treated with iv LAMB but due to side effects this was switched to VRC, while multiple lesions in the third patient were improved with nursing cures without specific antifungal treatment but follow‐up was not possible because she was exitus (Table ).…”

“…Phaeohyphomycosis is an increasingly recognised infection, in which Alternaria is one of the most commonly reported agents, mainly associated with both superficial and deep local infection in patients with impaired immunity, especially due to solid organ transplantation . Pulmonary transplantation, prostrate adenocarcinoma and a multiple pathological clinical history were predisposing factors to induce an immunocompromised condition in our patients to suffer cutaneous infection by this ubiquitous fungal genus.…”

“…Although several species have been associated as causal agent of alternariosis, A infectoria is the most frequent species identified in recent studies . However, in most cases its identification is limited to morphological features of the fungus growing in culture and confirmed by the analysis of the ITS barcode.…”

“…However, in most cases its identification is limited to morphological features of the fungus growing in culture and confirmed by the analysis of the ITS barcode. Even, in some cases, only ITS analysis is carried out directly from paraffin‐embedded tissue samples without culturing . Nevertheless, as stated before, the so‐called barcode for fungi has very limited resolution to distinguish closely related species in Alternaria , usually being only able to distinguish among Alternaria species‐groups or sections .…”

“…Therefore, alternative methods, such as DNA sequencing, are necessary for the correct identification of Alternaria species. In this sense, re‐identification of Alternaria clinical isolates by sequence analysis highlights that A infectoria, rather than A alternata, is the most frequently identified species, at least as causative agent of cutaneous alternariosis …”