Current concepts in Cryptococcosis

Abstract

Cryptococcus neoformans has become an increasingly important pathogen. Cryptococcosis is an important cause of morbidity and mortality in immunocompromised hosts and is the second most common fungal infection complicating AIDS. In recent years, research has focused on the host defenses against Cryptococcus and has led to an improved understanding of the capsular virulence of the organism, the mechanisms of T-cell defenses, and the role of phagocytic cells in the fungistasis and killing of cryptocci. Amphotericin B with or without flucytosine has clearly improved treatment of cryptococcosis, but therapy is associated with significant toxicity. Current investigation is focused on the triazoles, which may offer improved therapy for cryptococcosis. In this report, we review recent developments in the understanding of the host defenses against Cryptococcocus and discuss current recommendations for the management of cryptococcosis.

Polyamine depletion and growth inhibition ofCryptococcus neoformans by α-difluoromethylornithine and cyclohexylamine

“…The importance of infections due to Cryptococcus neoformans cannot be overemphasized [2,7,10,12,25]. Cryptococcosis, particularly meningitis, commonly occurs in patients with underlying immunodeficiency.…”

Cryptococcal Meningitis: Report of a Case

“…Unfavorable outcome has been associated with CSF elevated opening pressure, positive india ink, low WBC (<20x10 9 /L), no decrease in CSF or serum antigen during therapy, positive extraneural cultures, daily dose of >20 mg prednisone and patients with organ transplants or AIDS. 8 Despite the absence of dissemination, the present patient falls within the poor outcome category because of her diabetes mellitus, corticosteroid therapy, and progressive hydrocephalus.…”

“…2,8 Differences in the incidence of some signs and symptoms were noted between non-AIDS and AIDS patients: headache (87% vs 81%), fever (60% vs 88%), mental status changes (52% vs 19%), meningeal signs (50% vs 31%), photophobia (33% vs 19%), and seizures (15% vs 8%). Since 10% of non-AIDS or AIDS patients were asymptomatic, it is recommended that the CSF be examined in any patient with extraneural cryptococcosis.…”

“…Since 10% of non-AIDS or AIDS patients were asymptomatic, it is recommended that the CSF be examined in any patient with extraneural cryptococcosis. 8 Moreover, the skull and chest x-ray examinations also fail to provide a definitive diagnosis, as they may not show abnormality, or if abnormality is present (usually in less than half of the patients), it is not characteristic of the disease. 9 However, the cephalic CT is recommended in suspected cases with cryptococcal meningitis to ascertain the presence of mass lesions, granulomas, edema or hydrocephalus, especially since the CNS involvement can present in various ways: subacute or chronic meningitis, encephalitis, focal brain or spinal cord lesions.…”

“…2,12,13 Mortality in untreated cryptococcal meningitis reaches 86% as compared to 20% to 25% in patients treated with antifungal agents. 8 A six-week course of amphotericin-B has been the regimen of choice since 1951. [14][15][16] Although the combination of amphotericin-B and 5-FC has also been used, so far there is no conclusive evidence to show its superiority over using amphotericin-B alone.…”