Abstract

Background: Influenza A (H1N1) infection has been causing significant morbidity and mortality since 2009 epidemic all over the world. There needs to be rapid isolation of suspected patient to prevent further spread. Real-time polymerase chain reaction is a time consuming and costly test to confirm the diagnosis. There is a need of rapid and simple diagnostic test for H1N1.
Objective: The study was done to evaluate the utility of neutrophil–lymphocyte ratio and lymphocyte–monocyte ratio as screening tool for suspected H1N1 cases. Material and Methods: This was a retrospective study in which confirmed H1N1 cases from isolation ward for influenza were identified. Data were recorded in validated case record form. All the data regarding clinical history, examination findings, X-ray, and blood count were collected from case records of patients. Negative H1N1 cases were excluded from the study. Result: Mean age of patients was 27.7 year. Mean duration of stay was 5.85 days with range of 3–8 days. The most common symptoms were cough and sore throat (79.41%), fever (76.47%), and breathlessness (47.05%). Low WBC count was observed only in two patients (5.88%) Polymorphonuclear predominance was observed in 21 patients (61.76%). Polymorphonuclear to lymphocyte ratio was >2 in 21 patients and lymphocyte-to-monocyte ratio was observed >2 in 33 patients. Conclusion: P–L ratio and L–M ratio cannot be used as criteria of exclusion of H1N1 infection because of higher preva- lence of secondary bacterial infection. This needs to be further evaluated in larger patient population.