Cryptococcosis in the era of AIDS--100 years after the discovery of Cryptococcus neoformans

Abstract

Although Cryptococcus neoformans and cryptococcosis have existed for several millennia, a century has passed since the discovery of this encapsulated yeast and its devastating disease. With the advent of the AIDS pandemic, cryptococcal meningitis has emerged as a leading cause of infectious morbidity and mortality and a frequently life-threatening opportunistic mycosis among patients with AIDS. Both basic and clinical research have accelerated in the 1990s, and this review attempts to highlight some of these advances. The discussion covers recent findings, current concepts, controversies, and unresolved issues related to the ecology and genetics of C. neoformans; the surface structure of the yeast; and the mechanisms of host defense. Regarding cell-mediated immunity, CD4+ T cells are crucial for successful resistance, but CD8+ T cells may also participate significantly in the cytokine-mediated activation of anticryptococcal effector cells. In addition to cell-mediated immunity, monoclonal antibodies to the major capsular polysaccharide, the glucuronoxylomannan, offer some protection in murine models of cryptococcosis. Clinical concepts are presented that relate to the distinctive features of cryptococcosis in patients with AIDS and the diagnosis, treatment, and prevention of cryptococcosis in AIDS patients.

Gender Specific Differences in the Immune Response to Infection

“…(Casadevall and Perfect 1998). The literature on gender differences in C. neoformans infections is complicated as the majority of studies reported that males have an increased risk of C. neoformans infection (Amornkul et al 2003;Dromer et al 1996a, b;Hajjeh et al 1999;Micol et al 2007;Mitchell and Perfect 1995;Sorvillo et al 1997) while several studies, reported an increased risk of C. neoformans infections in females (Chuang et al 2008;Jean et al 2002). A possible explanation for this difference is that most of the patients in these two studies were not infected with human immunodeficiency virus (HIV).…”

Evidence of Microevolution in a Clinical Case of Recurrent Cryptococcus neoformans Meningoencephalitis

“…Filobasidiella neoformans (Cryptococcus neoformans) is an encapsulated yeast that causes self-limiting, asymptomatic pulmonary infections in immunocompetent hosts [1,2] and symptomatic infections in individuals with depressed cell-mediated immunity, particularly those with human immunodeficiency virus (HIV)-1 infection or lymphoproliferative disorders and those on immunosuppressive therapy due to organ transplantation [3,4]. It is worth noting that a significant decline in the incidence of cryptococcosis has been recently observed in AIDS patients, due to the use of highly active antiretroviral therapy (HAART).…”

Candidamykosen der Mundhöhle

“…Infolge interkontinentaler Migration und Ferntourismus treten solche "exotische" Systemmykosen vereinzelt auch in Europa auf [13]. Kryptokokkose, früher als "Europäische Blastomykose" fast nur bei Patienten mit Hodgkin-Lymphom beobachtet, ist inzwischen bei HIV-Patienten im AIDS-Stadium die häufigste terminale Systemmykose [34]. Die Erreger disseminieren hämatogen unter septischen Krankheitssymptomen und befallen,ausgehend von einer primären Lungeninfektion, terminal besonders das ZNS [35].…”