Epidemiology and trends of cryptococcosis in the United States from 2000 to 2007: A population-based study

Cryptococcal disease, caused by Cryptococcus neoformans and Cryptococcus gattii, is associated with significant morbidity and mortality but limited data exist on its incidence and impact. A study utilizing the Nationwide Inpatient Sample from 2000 to 2007 to examine the epidemiology and impact of cryptococcal disease in the United States was undertaken. The International Classification of Diseases 9th Version code was used to identify hospital discharges with diagnosis of Cryptococcus (117.5). Our primary outcome was the incidence rate of cryptococcal admissions. The impact of AIDS, age, and sex on hospitalization rates, mortality, and costs was assessed. The results showed that a total of 10,077 hospitalizations for cryptococcosis occurred corresponding to a weighted estimate of 49,010 cases. The median age was 43 years (interquartile range 34-54), and 26% were female. Approximately 64% of cases occurred in persons with AIDS. Although rates declined overall, age-adjusted rates were significantly higher in males with AIDS than in uninfected persons (p < 0.001). The mortality rate decreased but was greater in HIV-uninfected versus infected cohorts (12% versus 10%, p < 0.001). Conversely, hospital costs were greater in persons with AIDS ($40,671 versus $40,096, p=0.02). Although cryptococcal disease rates are decreasing over time, the associated mortality and costs remain concerning.