Association of ABO blood groups with dengue fever and its complications in a tertiary care hospital

CONTEXT: Dengue fever (DF) has been steadily increasing in India with outbreaks in certain areas taking the proportion of epidemics. Along with secondary dengue, several risk factors predispose to dengue hemorrhagic fever and dengue shock syndrome. Very few studies associating the relationship between dengue and its severity with ABO blood group have been documented. AIMS: The aim of this study was to determine the association between distribution of ABO Rh blood groups and DF and DF with thrombocytopenia. SETTINGS AND DESIGN: This was a retrospective descriptive study conducted at the clinical laboratory of the department of microbiology. MATERIALS AND METHODS: Dengue patients whose case record contained information on blood group were screened for details of blood group and confirmed dengue diagnosis. Randomly 384 case records were selected. These were divided into two groups; Group 1 included DF cases (platelet count >20,000) and Group 2 included DF cases with thrombocytopenia (platelet count <20,000). Control group consisted of patients other than dengue, whose blood grouping had been done; randomly 390 were selected and analyzed. STATISTICAL ANALYSIS USED: P value was calculated using the Chi-square test. Odds ratio were calculated using the Fisher's exact test. RESULTS: DF was higher in 23% of individuals with AB blood group as compared to 8.5% of controls (P = 0.0004), whereas patients with blood group O were significantly less affected with DF (P = 0.0048). Disease severity was not associated with any of the blood groups. CONCLUSIONS: Individuals with AB blood group are more prone to DF, whereas individuals with blood group O are less prone.