Cryptococcus neoformans is a ubiquitous environmental fungus that can cause life-threatening meningitis and fungemia. Risk factors for invasive Cryptococcus neoformans diseases include acquired immunodeficiency syndrome (AIDS), decompensated liver cirrhosis, cell-mediated immunity (CMI)-suppressive regimens without calcineurin inhibitors, and autoimmune diseases, according to a case-control study led by Dr. Chi-Tai Fang of National Taiwan University. The finding has been published on March, 2015 in PLoS ONE.

[Photo: Ms. Ying-Ying Lin and M.s Stephanie Shiau worked in Dr. Fang’s laboratory in 2010]

This research was conducted by master student, Ms. Ying-Ying Lin, and her advisor, Dr. Chi-Tai Fang, associate professor at the Institute of Epidemiology & Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan. Additional contribution was provided by 2010 Taiwan Tech Trek Program summer exchange student, Ms. Stephanie Shiau from the United States, who is now a PhD student at the department of epidemiology, Columbia University Mailman School of Public Health.

The Centers for Disease Control and Prevention (CDC) estimates that there are approximately one million new cryptococcal meningitis cases every year worldwide, with more than 70% of these cases occurring in sub-Saharan Africa. “C. neoformans infection is an important global health concern,” said Dr. Fang, who conducted the first cohort study on the clinical outcomes of cryptococcemia with his team in 2002.

Previous research has found that C. neoformans diseases often occur in the presence of acquired immunodeficiency syndrome (AIDS), liver cirrhosis, diabetes mellitus, or other medical conditions. To distinguish risk factors from comorbidities, Ms. Ying-Ying Lin, along with her advisor and Ms. Stephanie Shiau designed and performed a hospital-based, density-sampled, matched case-control study to better understand risk factors for C. neoformans.

The present study confirms previous clinical observations and animal studies on the critical role of impaired cell-mediated immunity in the pathogenesis of invasive C. neoformans diseases, and provides a more precise characterization of high-risk individuals. Knowledge on risk factors will enable physicians and public health authorities to develop better strategies to prevent this deadly disease among those with compromised immunity.