Applicability of volume conductivity and scatter parameters for early prediction of dengue virus infection

Introduction: Dengue virus infection is an acute febrile illness endemic in several countries including India. Although the management is empirical, early diagnosis is crucial for timely intervention to reduce the morbidity and mortality. The diagnosis of dengue virus infection mainly depends on serological testing and virus isolation which are costly and time-consuming. A simple blood test like complete blood count (CBC) run on five-part differential cell counter with volume conductivity, and scatter (VCS) data can help in predicting dengue infection without additional cost. Methods: In the present study, we analyzed VCS parameters of 337 febrile patients over the period of 1 year (January 2016 to December 2016). Out of these, 255 cases were positive for dengue serology and 82 were febrile controls. Comparative analysis of utility of previously published dengue factor, lymph index, and monocyte factor along with the “New Dengue Factor” introduced in the present study. Results: The “New Dengue Factor” proposed by us gave highest “positive likelihood ratio” for the diagnosis of dengue virus infection. Dengue factor proposed by Sharma et al. was the most “sensitive,” and “lymph index” proposed by Hawaldar et al. was the most specific followed by the “New dengue factor” introduced in the present study. Conclusion: Factors derived from VCS parameters are useful for early prediction of dengue virus infection without incurring additional cost and thus would contribute to better patient care