High Fluorescence Lymphocyte Count as an Early Predictor of Severe Thrombocytopenia in Dengue Infection

Abstract

Objective: Dengue infection (DI) is the most common arthropod-borne viral disease with symptoms ranging from mild flu like illness to fatal hemorrhagic fever. Thrombocytopenia is one of the common manifestations of dengue which can lead to life threatening bleeding. Currently, there is no validated test available that can predict the severity of thrombocytopenia in a dengue patient. Dengue has been well associated with presence of high fluorescence lymphocytes in the peripheral blood. High fluorescence lymphocyte count (HFLC) is a parameter generated at no extra cost when an automated complete blood count (CBC) is performed on Sysmex XN-1000 automated hematology analyzer. We aim to assess the significance and correlation of the HFLC with thrombocytopenia during the course of dengue infection especially during day 1 to 5 of the infection. Material and Methods: This is a cross sectional study and was conducted at Chughtai Institute of Pathology from August 2021 to October 2021. Total 312 patients, both males and females, who had NS1 positive confirmed dengue infection were included in the study. Their platelet count and HFLC were noted at the time of diagnosis using Sysmex XN-1000. Follow up CBC were analyzed for next 5 days to observe the severity of thrombocytopenia. Results: There is significant negative correlation between absolute HFLC and platelet count on day one to five of the infection. On receiver operator characteristic curve analysis, we found that HFLC < 0.5 x103/µL had 60% sensitivity and 71.8% specificity for severe thrombocytopenia (platelet count less than 50 x 103/µL on day 5 of the infection. Conclusion: HFLC is a negative predictive factor for severe thrombocytopenia and therefore can be used as an early predictor of disease progression. Key Words: Dengue infection, NS1 antigen, High fluorescence lymphocyte count, Thrombocytopenia, Automated hematology analyzer.

High fluorescent lymphocytes in dengue infection; A navigator for hematopathologists.

“…This difference may be due to our hospital that caters more female patients. 13,14 Another study conducted at Lahore and reported mean age of patients was 45 years which is consistent with our study. 14 Maximum number of cases were referred from OPD.…”

“…Due to country's geographic location, changing climate, growing population, unplanned urbanization, and lack of effective vector control programs, dengue has become endemic in Pakistan. 13,14 According to our study, females are more prone to dengue as compared to male. Most of the studies reported that male are more affected.…”

“…DENV-1, DENV-2, DENV-3, and DENV-4 are its four serotypes. 12 Dengue has been an issue in Pakistan since 2005, with the terrible outbreak occurring in 2011. Due to country's geographic location, changing climate, growing population, unplanned urbanization, and lack of effective vector control programs, dengue has become endemic in Pakistan.…”