Serum cyrptococcal antigen: diagnostic value in the diagnosis of AIDS-related cryptococcal meningitis.
ABSTRACT The incidences of HIV-AIDS patients with opportunistic infections of the central nervous system are increasing. Of these, cryptococcal meningitis is the most important and serious. A simple method for the diagnosis of cryptococcal meningitis is needed despite its variable clinical features and the lack of a capacity in most health facilities in Thailand to exclude it from other diseases especially mass lesions in the brain.
To identify the capability and cut off point of serum cryptococcal antigen for diagnosis and screening of cryptococcal meningitis in HIV-AIDS patients.
One hundred consecutive cases of HIV-AIDS patients suspected of having central nervous system infections were prospectively recruited for the study. The serum of all patients were examined for cryptococcal antigen by latex agglutination test, the Pastorex Cryptococcus manufactured by Sanofi Diagnostic Pasteur, France. If a test was positive, the serum dilution was carried out using 10-fold serial dilution. Every patient went through pre-defined standard investigations to derive at a definite diagnosis. The gold standard for diagnosis of cryptococcal meningitis was the presence of encapsulated yeast forms in the cerebrospinal fluid or a positive culture for cryptococcal neoformans from the cerebrospinal fluid.
Of 100 patients enrolled in this study, 58 patients had cryptococcal meningitis and serum cryptococcal antigen was detectable in 60 patients. If the cut-off point for a positive test was when the serum cryptococcal antigen titer was more than zero, then, the sensitivity of the test was 91.4 per cent, the specificity was 83.3 per cent, likelihood ratio if test positive (LR+) was 5.47, likelihood ratio if test negative (LR-) was 0.1, false positive was 16.7 per cent, false negative was 8.6 per cent.
We conclude that serum cryptococcal antigen is a simple and rapid screening method for diagnosis of cryptococcal meningitis.
- [Show abstract] [Hide abstract]
ABSTRACT: Cryptococcal meningitis (CM), a fungal disease caused by Cryptococcus species, is one of the most common opportunistic infections among persons with HIV/AIDS. The highest burden of disease is in sub-Saharan Africa and Southeast Asia, where limited access to antiretroviral treatment and appropriate antifungal therapy contributes to high mortality rates. Increasing focus has been placed on earlier detection and prevention of disease. Primary prophylaxis and screening may provide a survival benefit and can be cost-effective in settings where CM prevalence is high. The development of a new point-of-care cryptococcal antigen assay has the potential to transform both disease prevention and diagnosis.Current Fungal Infection Reports 12/2011; 5(4). DOI:10.1007/s12281-011-0070-x
- Journal of Clinical Microbiology 10/2000; 38(9):3520-1. · 4.23 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Central nervous system involvement is common in acquired immunodeficiency syndrome (AIDS), with Cryptococcus neoformans being an important cause among etiologies causing fungal meningitis. Seventeen human immunodeficiency virus (HIV)-positive adults with symptoms of chronic meningitis were investigated for fungal meningitis because of C. neoformans and a correlation was attempted with the CD4 counts of these patients. Cerebrospinal fluid and blood samples were collected for direct microscopy, culture, and serology. CD4 counts were determined by flow cytometry. Cryptococcal meningitis was seen in 5 (29.4%) patients, tubercular meningitis in 9 (52.9%) patients, HIV encephalopathy in 2 (11.7%), and cerebral toxoplasmosis in 1 patient. In patients with Cryptococcal meningitis both methods, ie, an India ink preparation and Gram staining gave similar results. Culture was positive in 3 patients (60%) whereas Cryptococcal antigen in cerebrospinal fluid was positive in 4 (80%) patients. The mean CD4 count was 120 +/- 55.13 cells/microL. The study provides information about the increasing incidence of Cryptococcal meningitis after the AIDS pandemic. It indicates progression of HIV infection toward AIDS and is useful as a reference to starting antiretroviral therapy in settings where facilities for determination of CD4 counts are not available. It also confirms that the course of Cryptococcal meningitis in Indian patients is similar to most studies.The Neurologist 08/2008; 14(4):247-51. DOI:10.1097/NRL.0b013e3181678a7a · 1.08 Impact Factor