Bacterial infection and male infertility: absence of immunoglobulin A with specificity for common Escherichia coli 0-serotypes in seminal fluid of infertile men.

We used an indirect solid phase radioimmunoassay to detect and quantitate immunoglobulin A (IgA) in male genital secretions with specificity for Escherichia coli (E. coli) antigen. We assayed the seminal fluid and expressed prostatic secretion (EPS) of a patient with chronic bacterial prostatitis (CBP) due to an 01 E. coli, the seminal fluid of 24 fertile men, and the seminal fluid of 62 men of infertile marriages. IgA directed apparently against the 0-antigen of the infecting E. coli was measurable in both the seminal fluid and EPS of the CBP patient. IgA in these specimens also bound to antigen in a mix of 8 common E. coli 0-serotypes that included an 01 E. coli. IgA with specificity for antigen in the mix of common E. coli 0-serotypes could not be detected in the seminal fluid of the fertile men or the men of infertile marriages. These data suggest that subclinical E. coli infections of the male reproductive tract are not commonly associated with infertility.