At the baseline, patients with a history of recurrent UTI had higher urinary levels of NGAL, CXC-motif chemokine ligand (CXCL)-1, IL-8, CXCL-10, monocyte chemoattractant protein (MCP-1), and tumor necrosis factor-alpha (TNF-α) than the controls; however, only the NGAL level was significantly higher in patients with a history of recurrent UTI (Table 2). Here, TNF is linked to bacterial urinary tract infection.