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Cryptococcosis associated with HIV negative Indian patients and HIV positive Indian blood donors
Z K Khan1, R Katiyar, R Shukla
1Medical Mycology Division, Central Drug Research Institute, Lucknow, India.
Abstract:
Cryptococcosis, particularly cryptococcal meningitis (CM), has become an increasing problem globally in the AIDS era. In the present investigation we have made an effort for the first time to study Indian cases (100) both HIV-positive (23 cases, male, mostly Indian professional blood donors, PBDs') confirmed by an ELISA test and Western Blot but asymptomatic for CM and HIV-negative (77:49 male and 28 female) asymptomatic or symptomatic. These subjects were patients from the Lucknow hospitals admitted during the period between February, 1991 to February, 1994, for suspected cryptococcosis or CM. Of those cases, 10% were positive for cryptococcosis or CM. Meningoencephalitis was the dominant clinical manifestation in four (HIV-negative) cases of CM. CT scanning of the head of those cases revealed a noncommunicating hydrocephalus due to aqueductal stenosis (in 2 cases) and a communicating hydrocephalus with granuloma (by MRI) in another case. The latex agglutination test (LAT) of the sera was positive for Cryptococcus antigen in 6 (26%) of the (HIV-positive) patients and 4 (5%), of the HIV-negative cases. In the cases of CM, there was a lower antigen titre in CSF than in the pronase-treated sera. The LAT was found to be useful in diagnosis of cryptococcosis, especially in asymptomatic cases. The CSF of CM-positive cases revealed low levels of glucose, reduced cell count and high proteins. Among the HIV-negative cases, the onset of meningitis in 4 cases was preceded by the presence of encapsulated budding yeast cells in CSF India ink smear, or cryptococci in a direct urine smear in one case. The CSF culture of 3 cases was positive for mucoid Cryptococcus neoformans, showing brown colour effect (BCE) on Staib agar (syn. Guizotia abyssinica creatinine agar, bird seed agar). The isolated yeast strains were identified as C. neoformans var. neoformans by physiological tests. The pathogenicity test of strains revealed virulence to BALB/c mice evidenced by a high mortality of mice and significantly (p < 0.05) high CN burden (> 4-5 mean log(10) cfu), in the brain followed by other visceral organs (lung, liver, spleen, kidney and heart). The in-vitro susceptibility (MIC mu gmL(-1)) of strains.
Insights
This study investigated 100 Indian patients for cryptococcosis, finding it in 10%. The latex agglutination test proved useful for diagnosing cryptococcal meningitis (CM), especially in asymptomatic cases.
Area of Science:
- Mycology
- Infectious Diseases
- Clinical Microbiology
Background:
- Cryptococcosis, particularly cryptococcal meningitis (CM), is a growing global health concern, especially in the context of the AIDS epidemic.
- This study is the first to investigate Indian cases of cryptococcosis, analyzing both HIV-positive and HIV-negative individuals.
Observation:
- The investigation included 100 patients from Lucknow hospitals (1991-1994), with 23 HIV-positive and 77 HIV-negative individuals.
- Ten percent of the cases tested positive for cryptococcosis or CM.
- Clinical manifestations included meningoencephalitis in four HIV-negative CM cases, with hydrocephalus identified via CT and MRI scans.
Findings:
- The latex agglutination test (LAT) detected Cryptococcus antigen in 26% of HIV-positive and 5% of HIV-negative patients, proving useful for diagnosing cryptococcosis, particularly in asymptomatic individuals.
- Cerebrospinal fluid (CSF) analysis in CM cases showed low glucose, reduced cell count, and high protein levels.
- Cryptococcus neoformans was identified in CSF and urine samples, with strains confirmed as C. neoformans var. neoformans and exhibiting virulence in mice.
Implications:
- The findings highlight the diagnostic utility of LAT for cryptococcosis, even in asymptomatic patients.
- Understanding the clinical presentation and diagnostic markers of CM in the Indian population is crucial for timely intervention.
- Further research into the pathogenicity and in-vitro susceptibility of Cryptococcus strains is warranted.