Cryptococcus and Cryptococcosis: Updates on Pathogenesis, Diagnosis and Treatment Strategies for HIV Infected Patients

Cryptococcosis is a serious fungal infection in both huaman and animals caused by members of the Cryptococcus neoformans/ Cryptococcus gattii species complex. The main route of entry is respiratory tract. Meningitis is the most common clinical manifestation of cryptococcosis in immunocompromised patients and considered as one of AIDS defining illnesses. The known natural sources of the fungus are avian (pigeon, chicken, and other birds) excreta, dead plants and trees like Eucalyptus, Pine, and Fig species. Cryptococcus neoformans/ Cryptococcus gattii species complex have well defined virulence factors that help them to survive and multiply in macrophages and monocytes, escape into blood and disseminate throughut the body. Laboratory diagnosis of cryptococcosis is based on direct microscopy examination, fungal isolation, serology and molecular analysis of serum and cerebrospinal fluid. Amphhotercin B combined with other antifungals including 5-flourocytosisne and fluconazole monotherapy are used for treatment of cryptococcosis. Treatment in HIV infected patients consist of three phases including induction, consolidation and maintenance therapy. The preferred therapeutic regimen is combination therapy of antifungal and highly active antiretroviral therapy. In this article, we summarized recent studies on pathogenesis, diagnosis, and treatment of cryptococcosis in HIV infected patients.