A Novel Opportunistic Infection in South Africa

The AIDS pandemic has brought a unique appreciation of the human immune system and specific infections related to deterioration of portions of it — in particular, the CD4 cell. Now, researchers present evidence of infection with a new fungal species in South Africa.

From July 2008 through July 2011, a surveillance system was used to identify the cause of systemic fungal infections among patients presenting to University of Cape Town–affiliated hospitals — institutions that serve communities in which up to 30% of adults are HIV infected. Cases were defined by skin biopsy showing deep fungal invasion, culture yielding a dimorphic fungus, and a clinical syndrome compatible with disseminated fungal infection.

Overall, a dimorphic fungus was cultured from specimens in 24 cases. Phylogenetic analysis of five genes revealed that 13 of these 24 infections were caused by a novel species in the genus Emmonsia. The 13 patients with the novel pathogen had advanced HIV infection and low CD4-cell counts (median, 16 cells/mm³; interquartile range, 10–44); their median age was 34 years. All had widespread skin lesions, 12 had fever, and 11 had chest radiographs compatible with pulmonary tuberculosis. Eight of the nine who underwent liver-function testing had elevated γ-glutamyltransferase or alkaline phosphatase levels. Three patients died.