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Symptoms and Signs of Urinary Tract Infection (UTI)

Doctor's Notes on Urinary Tract Infection (UTI)

A urinary tract infection is an infection anywhere in the urinary tract. Infections of the urethra (urethritis) and the bladder (cystitis) are common lower urinary tract infections. Urinary tract infections are sometimes referred to as UTIs and are most commonly caused by bacteria. Most commonly, the causative bacteria are those that normally live in the human intestines. The bacterium Escherichia coli (E. coli) causes the majority of UTIs.

Signs and symptoms of urinary tract infection include pain and burning with urination (dysuria), feeling an urgent need to urinate (urgency), frequent urination, and blood in the urine. Other possible associated symptoms can include fatigue, fever, cloudy urine, dark urine, foul-smelling urine, weakness, muscle aches, and abdominal pain.

Medical Author:
Medically Reviewed on 4/5/2019


Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.