Fusarium solani Skin and Soft Tissue Infection in a Patient With Chronic Sclerosing Skin Graft-vs-Host Disease: A Case Report.

BACKGROUND Fusariosis is an exceedingly rare infection most often attributable to the fungus Fusarium solani. It is a rare but known cause of invasive mold infections in immunocompromised patients post-hematopoietic cell transplant (post-HCT). Fusariosis can be extremely difficult to treat due to its tendency to disseminate in the context of underlying immunosuppression, and its high in vitro resistance to mainline antifungal agents. CASE REPORT Here we present a post-HCT patient undergoing immunosuppressive therapy for diagnosed chronic graft-versus-host disease (GVHD) of the skin who presented with subacute skin and soft tissue infection of the right hand and arm with multi-drug-resistant F. solani. She initially presented with complaints of erythema and worsening wound exudation at her GVHD site, which had worsened over the course of days. The diagnosis was delayed due to chronic and diffuse scleroderma-like changes due to the underlying GVHD. Following fungal cultures demonstrating multi-drug resistance, the patient was successfully treated with an investigational antifungal drug, fosmanogepix. CONCLUSIONS This case demonstrates the importance of including fusariosis as a differential diagnosis in patients post-HCT, even long into the post-transplant period. Contrary to disseminated fusariosis, which arises most commonly in neutropenic patients, isolated skin and soft tissue fusariosis can occur in non-neutropenic post-transplant patients with chronic GVHD receiving immunosuppression. In addition, this case outlines the high complexity of fusariosis treatment due to the capacity of this organism to develop multi-drug-resistance to mainline antifungals. This report illustrates clinical and radiographic improvement following implementation of fosmanogepix therapy in a severely immunocompromised patient with GVHD and complex multi-drug-resistant Fusarium infection.