Acute uncomplicated urinary tract infection (UTI) is one of the most common bacterial infections in adults that may involve the lower or upper urinary tract or both.
Acute uncomplicated cystitis is an infection limited to the lower urinary tract while acute uncomplicated pyelonephritis is an infection that involves the upper urinary tract (renal parenchyma and pelvicaliceal system) that usually has significant bacteriuria.
Recurrent UTI is characterized by ≥2 culture-proven episodes of uncomplicated and/or complicated UTI in the last 6 months or ≥3 episodes with positive cultures in the last 12 months in patients with no urinary tract structural or functional abnormalities.