New Insights into HIV/AIDS-Associated Cryptococcosis

Abstract

Cryptococcal meningitis is a life-threatening opportunistic fungal infection in both HIV-infected and HIV-uninfected patients. According to the most recent taxonomy, the responsible fungus is classified into a complex that contains two species (Cryptococcus neoformans and C. gattii), with eight major molecular types. HIV infection is recognized worldwide as the main underlying disease responsible for the development of cryptococcal meningitis (accounting for 80-90% of cases). In several areas of sub-Saharan Africa with the highest HIV prevalence despite the recent expansion of antiretroviral (ARV) therapy programme, cryptococcal meningitis is the leading cause of community-acquired meningitis with a high mortality burden. Although cryptococcal meningitis should be considered a neglected disease, a large body of knowledge has been developed by several studies performed in recent years. This paper will focus especially on new clinical aspects such as immune reconstitution inflammatory syndrome, advances on management, and strategies for the prevention of clinical disease.

Figure 1

Worldwide geographic diffusion of different serotypes of Cryptococcus neoformans complex (based on [–48]).

Figure 2

Patients with cryptococcal meningitis and disseminated infection with multiple papular and molluscum-like lesions on the face.

Figure 3

India ink preparation of cerebrospinal fluid showing yeast cells some of which budding surrounded by large capsule (Courtesy Dr Giuseppe Giuliani).

Figure 4

Liver histology showing PAS-positive yeast cells in a case of disseminated cryptococcosis (Courtesy Dr. Carlo Parravicini).