The polymorphonuclear neutrophil (PMN) is the primary pro-inflammatory cell in the host response to bacterial infection and, as the first line of defence, is the principal cell responsible for the recognition, phagocytosis and killing of bacteria. PMN function is known to be defective in the urine. High osmolarity is physiologic in the urine and this hypertonic environment has been shown to compromise neutrophil function. In this study, PMN function was found to be suppressed in urine. This correlated with significant cell death, both by apoptosis and necrosis. The amino acid taurine down regulated PMN cell death and preserved function in the urine, suggesting taurine as a therapeutic option for urinary tract infection.