Correlation of clinical outcome with laboratory parameters in children with dengue infection: An appraisal from a tertiary children’s hospital in India

Abstract

Introduction: Dengue infection is caused by the dengue virus (arbovirus), the incidence of which is increasing in India. In dengue endemic settings, early diagnosis and monitoring for complications are important, especially in children. Concurrent testing of NSI antigen, dengue specific IgG and IgM will help to diagnose patients with suspected dengue fever.Objective: To correlate the clinical profile and outcome of dengue fever with detection of NSI antigen, dengue specific IgG and IgM antibody, hematological and biochemical parameters and blood component utilization.Methods: All children presenting to Rainbow hospital and diagnosed with dengue infection using NS1 and dengue specific IgG and IgM antibody during a one year period (1st November 2016 to 31st October 2017) were included in the study. The haemogram and biochemistry parameters were done using automated analyzers. Inpatients were classified as severe or non-severe based on clinical and/or laboratory evidence. The degree of association between clinical parameters and disease severity in relation to NS1 positivity was expressed as an odds ratio.Results: Among 213 children diagnosed, 126 were treated as inpatients and the rest as outpatients. The age range of the study sample was 6 months to 15 years. NS1 positivity was observed in 72.3 % patients. NS1 positivity, when compared to severity of disease was significant (Odds ratio: 2.3; p<.05). One death was reported in the severe group. Chi square test applied to assess the correlation of platelet count and NS1 positivity was also significant (Z score: 3.8 p<.05). Among the NS1 positive patients, in 8.5% (7) patients, very severe thrombocytopenia of <25000 cells/ mm3 was observed.Conclusions: Using all three tests (NS1, dengue specific IgM and IgG) was useful, as in 59 (27.7%) patients, despite a negative NS1, based on a positive dengue antibody response (IgG and/or IgM), the patients were admitted and monitored. NS1 positivity was associated with a higher risk of thrombocytopenia in this study.

Keywords

• dengue, nsi positivity, thrombocytopenia, blood transfusion