#CRYPTOCOCCUS NEOFORMANS INDIA INK SERIAL#

The overall (n = 194) median for quantitative cultures was 820 CFU/ml (IQR = 10 to 73000). 127 samples were positive for all these three tests. Of the 194 CrAg LFA positive CSF samples tested from different time points during antifungal therapy, 152 were positive for India ink, 186 were positive for acridine orange, and 151 were positive for quantitative cultures. Performance of India ink and acridine orange against culture and CrAg We hypothesized that with the availability of a florescent microscope in a clinical laboratory, acridine orange may be a more sensitive alternative to India ink light microscopy in the detection of Cryptococcus yeasts in CSF.

#CRYPTOCOCCUS NEOFORMANS INDIA INK SERIAL#

In this study, we used acridine orange to detect cryptococcal yeasts in fresh whole CSF in comparison to India ink stain at serial time points during antifungal treatment in a clinical setting. Earlier work done by Cohen et al, 1984 showed no apparent advantage of acridine orange over india ink for the rapid identification of Cryptococcus neoformans using three laboratory strains. It emits yellow fluorescence when it binds RNA and green fluorescence when it binds DNA. It has been used to stain samples for viability staining, epifluorescence microscopy and is particularly useful in the rapid screening of sterile biological specimens from clinical and non-clinical materials. The poor sensitivity of India ink may lead to misdiagnosis hence increasing the burden and mortality due to cryptococcal meningitis in resource limited settings where it is still utilized.Īcridine orange is a fluorescence dye used to stain acidic vacuoles, DNA, and RNA in viable cells. The new point of care CrAg lateral flow assay is in fact more sensitive and user friendly in different sample types. However, many recent studies done in sub-Saharan Africa in clinical settings demonstrated low and poor sensitivity of India ink in the diagnosis of cryptococcal meningitis. It is still being used in some resource limited settings of sub-Saharan Africa where the burden due to cryptococcal meningitis is highest. India ink has over time been used in the rapid diagnosis of cryptococcal meningitis using cerebrospinal fluid (CSF) among AIDS patients. However, detection of the cryptococcal antigen (CrAg) in CSF, serum and whole blood has recently gained more popularity with better sensitivity. Culture of cerebrospinal fluid (CSF) is the gold standard for diagnosis of CM. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Ĭompeting interests: The authors have declared that no competing interests exist.Ĭryptococcal meningitis (CM) is the most common cause of adult meningitis in Africa accounting for 15%–25% of AIDS-related deaths with majority of the cases registered in sub-Saharan Africa. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.ĭata Availability: All relevant data are within the paper and its Supporting Information files.įunding: Financial support for this research was provided by the National Institutes of Health (R01NS086312, T32AI055433 R25TW009345), Grand Challenges Canada (S4 0296-01), and United Kingdom Medical Research Council (MR/M007413/1). Received: ApAccepted: JPublished: July 27, 2017Ĭopyright: © 2017 Kwizera et al. Rodrigues, OSWALDO CRUZ FOUNDATION, BRAZIL Citation: Kwizera R, Akampurira A, Williams D, Boulware DR, Meya DB, on behalf of the ASTRO-CM Study Team (2017) Acridine orange fluorescent microscopy is more sensitive than India ink light microscopy in the rapid detection of cryptococcosis among CrAg positive HIV patients.

Cryptococcus neoformans india ink