Abstract
Background: In vivo T-antigen activation is a rare phenomenon caused by the effect of microbial sialidase on red blood cells (RBCs). Its pathogenetical relevance for acute hemolysis is discussed controversely. Patients and Methods: Two of the 3 patients were neonates that suffered from necrotizing enterocolitis. At the time when they were transferred to our hospital, one showed massive hemolysis, the other significant hyperbilirubinemia. The 3rd patient was an polytraumatized adult who showed sepsis and massive hemolysis 1.5 days after the accident. T antigen was tested in all these patients using Arachis hypogea lectins from two manufacturers and a Glycine soja lectin. Results : RBCs of both neonates showed positive reactions with the Arachis hypogea lectins from both manufacturers and with the Glycine soja lectin, whereas RBCs of the polytrauma patient had a positive reaction only with one of the Arachis hypogea lectin reagents (that with the higher titer) and did not react with the Glycine soja lectin. Bacteriological examinations revealed Clostridium butyricum in an intraoperative abdominal swab from one of the neonates. In the polytrauma patient, Clostridium perfringens could be isolated from three intraoperative swabs taken from different wounds. Conclusions: Hemolysis in critically ill patients may be caused by bacterial toxins, especially in cases of necrotizing enterocolitis or anaerobic wound infection. Detection of T-antigen activation on red blood cells may sometimes be helpful to draw attention to life-threatening infections in such patients and to distinguish them from other causes of acute hemolysis.