Nalidixic acid resistant Salmonella paratyphi A causing urinary tract infection in a patient with nephrolithiasis: Case report

Salmonella urinary tract infections (UTIs) are unusual and occur most often in infants and those over 60 years. S. paratyphi has been reported extremely rarely as a cause of UTI. Recovery of S. typhi is also rare from urine and can occur following a recent episode of typhoid fever, or in chronic carrier states involving the urinary system, and occasionally following localized UTI due to S. typhi. Studies have reported 0.07% of urinary tract infections diagnosed in 15 year duration to be due to nontyphoidal salmonella (NTS) and 0.24% of organisms cultured from urine were NTS. NTS species isolated from urine include S. enteritidis, S. typhimurium, S. heidelberg, S. infantis, S. newport. Cases of other unusual extra-intestinal infections caused by S. paratyphi A include fulminant hepatic failure, primary septic arthritis of the hip and pleural effusion. Because of its extreme rarity as a uropathogen, and importance of administering appropriate antimicrobial for treating urinary tract infection caused by nalidixic acid resistant and fluoroquinolone sensitive Salmonella paratyphi A, we report such an infection from India in an elderly man with renal and ureteric stones.