See CDC
Introduction:
Cryptococcus neoformans is a fungus that lives in the environment throughout the world.
People can become infected with C. neoformans after breathing in the microscopic fungus, although most people who are exposed to the fungus never get sick from it.
C. neoformans infections are rare in people who are otherwise healthy; most cases occur in people who have weakened immune systems, particularly those who have advanced HIV/AIDS. Other conditions that predispose individuals to infection are steroid treamtent, diabetes and cancer. It is not considered communicable among humans.
C Neoformans is monomorphic unlike other dimorphic pathogens. It can be identified with India Ink (has a wide capsule) and is the leading cause of meningitis in AIDS patients.
Pathology:
–Metabolism: A key factor influencing the virulence of C. neoformans is adenosine triphosphate (ATP), which serves as the primary energy currency for cells. ATP is crucial not only for cellular metabolism but also for various processes that enable C. neoformans to thrive and cause disease within the host. Research has shown that disruption of ATP biosynthesis results in a complete loss of virulence in C. neoformans. The loss of adenylosuccinate synthetase (AdSS) leads to adenine auxotrophy and a consequent reduction in virulence in murine models. This distinct structural differences between fungal AdSS and its human counterpart, positions AdSS as a promising target for antifungal drug development.
Cryptococcal meningitis (CM)
Cryptococcal meningitis is a life-threatening fungal infection caused principally by Cryptococcus neoformans and Cryptococcus gattii. Generally, C. gattii is the most common cause of CM in immunocompetent patients, while C. neoformans is primarily responsible for disease in immunocompromised patients. See Day
Risk Populations/Symptoms/Transmission:
Despite CM being more common in immunocompromised patients, CM can also arise in apparently immunocompetent patients. Recent figures estimate an annual global CM incidence of 223,100 cases in patients infected with human immunodeficiency virus (HIV), resulting in 181,100 deaths.
Treatment:
Treatment is with amphotericin B or flucytosine