Urinary tract infections and blood groups: Do they relate?

The urinary tract is one of the most common places for the occurrence of bacterial infections, especially in women. Urinary infection can be defined as an infection of the urinary tract structures which occurs, generally, as a consequence of the presence or colonization of bacteria, like Escherichia coli (E.coli) and other Enterobacteriaceae. The aim of this study was to evaluate the relation between urinary tract infections (UTIs) and blood groups. The population of this study consisted of 307 patients (83 men and 224 women) from the District Hospital of Figueira da Foz, E.P.E. (HDFF, E.P.E.) and from the Coimbra Health School (ESTeSC) in Portugal. The AB0 blood groups were determined through a gel-test methodology. The microorganisms identification was made using the VITEK ® 2 Compact equipment. In a total of 307 patients, the most common pathogen was E. coli with 48.4%, followed by Klebsiella pneumoniae, with 17%. Infection by E. coli was significantly more common in patients with A blood group phenotypes (p<0.0005). A statistically higher risk for developing urinary tract infections in women compared to males (p<0.001) was found. The results suggest that E. coli was the main pathogen causing urinary tract infections, and we found statistically significant association between A blood group phenotypes and this infection. These results might be useful for describing an individual’s risk for a higher predisposition in developing urinary tract infections.