TLR4 and urethritis: In this study, we summarize the results of a case-control study examing whether polymorphisms and expression in TLR4 and CXCR1 are associated with susceptibility to acute pyelonephritis, chronic UTI, and acute cystitis and urethritis in UTI patients in China, and evaluating whether astragalus can boost innate immnue respons against UTI through enhancing TLR4 expression.