P1 blood group phenotype, secretor status in patients with urinary tract infections.

We have examined the distribution of P antigen, Lewis blood group phenotypes and secretor status of 65 patients with E. coli UTI (20 asymptomatic bacteriuria, 20 cystitis and normal radiology, 25 reflux nephropathy) and 45 controls who have never experienced a UTI episode. The distribution of Lewis blood group antigens was similar in all UTI groups and in the controls. The incidence of non-secretors in the reflux nephropathy group was similar to that in controls (24% versus 31%). The P1 phenotype was present in 100% of patients with asymptomatic bacteriuria, 80% with cystitis and controls and only 44% with reflux nephropathy. The combined P1/non-secretor phenotype was observed in 45% of patients with asymptomatic bacteriuria, 30% with cystitis, 12% with reflux nephropathy and in 22% of control healthy individuals. P2/secretor phenotype was demonstrated in 44% of patients with reflux nephropathy and in only 11% of controls. Our data suggest that having P2 blood group protects against asymptomatic colonization of the urinary tract, but is associated with the type of infection responsible for scarring in reflux nephropathy. It also appears that being a non-secretor does not predispose to renal scarring and that combined P2/secretor phenotype may be linked with susceptibility to reflux nephropathy.