<prompt> Most common cause of urinary tract infection in children is -EColiKlebsiella sp.Psedomonas AerognosaCandida  <response>: Ans. is a i.e., E Coli o Bacterial infections are the most common cause of UTI, with E coli being the most frequent pathogen, causing 75- 90 of UTIs. Other bacterial sources of UTI include the following: Klebsiella species Proteus species Enterococcus species Staphylococcus saprophyticus, especially among female adolescents and sexually active females Streptococcus group B, especially among neonates Pseudomonas aeruginosao Fungi Candida species may also cause UTIs, especially after instrumentation of the urinary tract. Adenovirus is a rare cause of UTI and may cause hemorrhagic cystitis. 