Diagnosis utility of various serological markers including NSI antigen for timely detection of dengue virus infection

Introduction: Fifty to hundred million individuals are believed to be infecting with dengue virus infection worldwide in a year. The dengue virus infected patient presents with varied clinical symptoms. Mostly serological tests are used to detect IgM and IgG antibodies. Few workers also used NS1 antigen for early diagnosis of dengue infection. Therefore, the present study was planned to detect dengue infection timely in the suspected cases by using the various parameters like NS1 antigen, IgM, IgG antibodies along-with platelets. Materials and Methods: Serum specimens from 777 suspected dengue patients were collected and were analyzed for NS1 antigen, IgM and IgG antibodies using the immunochromatography test kit according to manufacturer's instructions. Platelet counts were also observed for all positive cases. Results: Out of 777, one hundred ninety-nine (25.6%) patients were found to be positive for either one or more dengue markers (NS1, IgM, IgG). Out of 199 positive specimens, NS1 only, IgM only and IgG only were positive for 128(64.3%), 34(17%) and 3(1.5%) cases respectively. NS1 along with IgM, IgG and IgM+IgG were positive in 12(6.0%), 2(1.0%) and 18(9.0%) cases respectively. Thrombocytopenia was observed in 155(77.8%) dengue positive cases. Conclusion: Detection of NS1 antigen along with IgM antibodies emerge to be timely, highly specific and reliable for diagnosis of dengue infection. Platelet counts supports as an accessory test for diagnosis of dengue infection.