Disseminated Rhizopus microsporus infection in a patient on oral corticosteroid treatment: a case report

A 71-year-old male with mild steroid-induced hyperglycaemia was diagnosed with a lethal invasive Rhizopus microsporus infection. Disseminated zygomycosis is a rare entity and is most frequently found in neutropenic patients with haematological malignancies, post-transplants or in patients on deferoxamine therapy. Infection is characterised by tissue infarction and necrosis due to angioinvasive hyphae. Culture of Zygomycetes is necessary for species determination but histology is a must to prove the infection. Ante-mortem diagnosis and culture is challenging and therefore mortality approaches 100%. Apart from amphotericine B, most anti-fungals have no activity against Zygomycetes but posaconazole might offer new possibilities as a first-line agent. Timely diagnosis, rapid surgery of infected tissue, correction of underlying disorders and correct anti-fungal therapy might be life-saving. Due to the increasing use of potent immunosuppression, stem cell and organ transplants and possibly selection for Zygomycetes by prior treatment with broad-spectrum antifungal therapy, the incidence of zygomycosis is rising. Therefore, clinicians might encounter an increasing number of zygomycosis cases in the near future.