A case-control study on the association between dengue infection and monocyte anisocytosis

Abstract

Background: This study aimed to determine the association between dengue infection and monocyte anisocytosis and other Complete Blood Count (CBC) parameters using automatic blood cell analyzer (DxH800) among admitted patients at University of Sto. Tomas Hospital.Methods & Materials: An observational analytic study is done using a hospital-based, 1:1 unmatched case-control study design and enrolling incidents of dengue patients admitted at the University of Sto. Tomas Hospital between October 2012 to September 2013. A dengue infection case is defined as any patient admitted at University of Sto. Tomas Hospital who is found positive to nonstructural protein 1 (NS1) test and a control is defined as any randomly selected admitted patient seen at the laboratory, who is found negative for non-structural protein 1 (NS1) test anytime from October 2012 to September 2013.Results: Adjusting for age and gender of subjects, multivariate analysis using logistic regression showed that monocyte volume≥ 195fL (OR = 4.57, p = 0.0003), monocyte volume standard deviation ≥ 30 fL (OR = 6.99, p = 0.0001), platelet count ≤ 150,000/uL (OR = 4.33, p = 0.0000), and WBC count≤ 2,000/uL (OR = 6.03, 0.0101) are associated with dengue infection. Monocyte percent and mean platelet volume are found to be confounders in the study. Conclusion:There is an association between dengue and monocyte volume standard deviation ≥ 30fL (monocyte anisocytosis), monocyte volume ≥195 fL, platelet ≤150,000/uL and WBC count ≤ 2,000/uL. To further strengthen the finding on the possible association of monocyte volume standard deviation (monocyte anisocytosis) ≥ 30fL and monocyte volume >195 fL, the investigator recommends that clinical information of subjects be included in similar studies that will be conducted in the future.