Insights into fungal pathogenesis from the iatrogenic epidemic of Exserohilum rostratum fungal meningitis.

In 2012 the medical community in the United States faced an unprecedented outbreak of fungal meningitis caused by Exserohilum rostratum associated with injections of contaminated lots of methyprednilsone acetate. Rapid response by public health authorities led to the identification of the cause of the outbreak and the epidemic quickly abated, even though new cases were still being reported many months later. Although the cause of the outbreak is known there are many uncertainties regarding the management of infected individuals and the long term risk for those who were exposed to this organism. The epidemic of E. rostratum infections illustrates how an organism that normally has low pathogenic potential for humans can transform into a very dangerous pathogen when conditions are changed such that skin barriers are breached while it is simultaneously delivered with an immunosuppressive drug. Furthermore, this epidemic highlights the potential threats to human and animal health from the fungal kingdom.