We use febrile UTI because the clinical syndrome of interest because this is often how patients present, and fever mainly determines the acceptable treatment. According to the above mentioned classifications, febrile UTI includes complicated UTI with fever, acute prostatitis, acute (un-)complicated pyelonephritis and, as has been suggested, the urosepsis syndrome. Febrile urinary tract infection (UTI) is one of the most common bacterial illnesses in children. As febrile UTI may lead to acute renal parenchymal damage, possible permanent renal scarring, decreased renal function and endstage renal disease, early diagnosis and treatment are important.Given these various classifications of UTIs in the literature, it likely makes more sense to classify these patients uniformly according to their presentation, in which fever reflects the presence of a parenchymal inflammation.