The screening of direct Coombs test in newborns and the effect of its positivity on morbidity; a single center experience

Purpose: Immune mediated hemolysis has an important role in the etiology of indirect hyperbilirubemia (IHB) in newborns. Immune mediated hemolysis can be shown using Direct Coombs Test (DAT). Antibodies bound to erythrocytes are determined by coombs test. DAT and blood group screening in cord blood are routinely performed in some centers, though controversial. In this study, our aim was to investigate the DAT positivity in newborns borned at our hospital and to evaluate the causes of DAT positivity and its effect on morbidity. Materials and methods:This study was performed at Kecioren Training and Research Hospital between July 2012 and April 2013. The electronic records of all newborns and their mothers were studied. Babies’ cord blood group and DAT results, presence of any immune hemolytic disease and a history of phototherapy due to IHB was investigated. Results: DAT was found positive in 6.6% of 1122 newborns and in 37.6% of newborns with IHB. The rate of hospitalisation due to IHB was significantly high in newborns with DAT positivity (p<0.001). Sixty two percent of newborns with DAT positivity and 7% of newborns with DAT negativity was treated with phototherapy. DAT positivity and the necessity of phototherapy was lower in newborns with Rh blood group incompatibility than in newborns with other blood groups (p<0.01). There was no statistically significant difference in DAT positivity between newborns with AO, BO, ABO-Rh incompatibilities.