Title: Weil-Felix Test: Still a Useful Diagnostic Test for Scrub Typhus??
Authors: Dr Sujatha S R, Dr Tejashree A
DOI: https://dx.doi.org/10.18535/jmscr/v7i5.119
Abstract
Background: Scrub typhus is a mite born Rickettsial disease which is considered to be a re-emerging disease and one of the differential diagnosis of FUO. Often Rickettsial infection is undiagnosed because of its unusual presentation & lack of reliable as well as affordable diagnostic test .If the disease is undiagnosed it leads to complications with high mortality & morbidity.
Materials & Methods: Present study was done to evaluate the serological tests like Weil Felix, ELISA & IFA, using IFA as the gold standard. About 100 non replicative serum samples were collected from patients with PUO after excluding other causes of PUO. Serum samples were subjected to all the three tests WeilFelix (detect OXK antibodies),ELISA (detecting IgM antibodies against Orientia tsutsugamusghi ) & IFA( detecting IgM antibodies to Orientia tsutsugamushi ) & compared.
Results: 27/100 were positive for IgM for scrub typhus using IFA, 22 were positive by Weil Felix, 26 were positive by IgM ELISA for Scrub typhus
Sensitivity and Specificity of Weil-felix test in comparison with IFA was 33.3% & 84.68%, ELISA was 73% & 83.3%
Conclusion: Our study shows Weil –Felix test as a less sensitive & less specific test instead ELISA test can be used since it as better sensitivity & specificity.
Keywords: Orientia tsutsugamushi, WeilFelix, ELISA, IFA.
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