Additionally, the only in vivo human study that investigated the impact of inflammation on the activity of renal transporters showed that the clearance of furosemide, an OAT1/3 in vivo probe drug, was significantly reduced by ~40% in pregnant women during acute pyelonephritis vs. after resolution of pyelonephritis (i.e., paired study), indicating an inflammation-induced downregulation of OAT1/3 activity [17]. This evidence concerns the gene SLC22A6 and pyelonephritis.