Abstract
Visceral leishmaniasis (VL) is one of the leading infectious diseases affecting developing countries. Colloidal gold-based diagnostic tests are rapid tools to detect blood/serum antibodies for VL diagnosis. Lack of uniformity in the performance of these tests in different endemic regions is a hurdle in early disease diagnosis. This study is designed to validate a serum-based dipstick test in eight centres of six countries, India, Nepal, Sri Lanka, Brazil, Ethiopia and Spain with archived and fresh sera from 1003 subjects. The dipstick detects antibodies against Leishmania donovani membrane antigens (LAg). The overall sensitivity and specificity of the test with 95% confidence intervals were found to be 97.10% and 93.44%, respectively. The test showed good sensitivity and specificity in the Indian subcontinent (>95%). In Brazil, Ethiopia, and Spain the sensitivity and specificity of the dipstick test (83.78–100% and 79.06–100%) were better as compared to the earlier reports of the performance of rK39 rapid test in these regions. Interestingly, less cross-reactivity was found with the cutaneous form of the disease in Spain, Brazil, and Sri Lanka demonstrating 91.58% specificity. This dipstick test can therefore be a useful tool for diagnosing VL from other symptomatically similar diseases and against cutaneous form of leishmaniasis.
Highlights
Visceral leishmaniasis (VL) is one of the leading infectious diseases affecting developing countries
The blind test was conducted with archived serum samples of 143 confirmed Visceral Leishmaniasis (VL) cases, 11 post Kala-azar dermal leishmaniasis (PKDL) and 57 control samples at Rajendra Memorial Research Institute of Medical Sciences (RMRIMS), Patna during March 2013 to June 2013
We report the performance of leishmanial membrane antigens (LAg), a leishmanial membrane extract, as a diagnostic marker in a dipstick format and validated this across six VL endemic countries for global comparative evaluation
Summary
Visceral leishmaniasis (VL) is one of the leading infectious diseases affecting developing countries. Less cross-reactivity was found with the cutaneous form of the disease in Spain, Brazil, and Sri Lanka demonstrating 91.58% specificity. This dipstick test can be a useful tool for diagnosing VL from other symptomatically similar diseases and against cutaneous form of leishmaniasis. Even though DAT and IFAT perform well in almost all endemic areas[9] they show variations in the antigen preparations and high level of cross reactivity. They are time consuming, entail expertise and need high-end instruments which restrict them to laboratories. Serological tests for VL diagnosis often showed cross reactivity with CL patients
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
