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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

Urinary Tract Infection (UTI) Symptoms

Symptoms and signs of a urinary tract infection include

  • pain or burning when urinating (dysuria);
  • frequent urination;
  • sudden urge to urinate (bladder spasm);
  • frequent or persistent urge to urinate without much urine passing when you go;
  • sense of incomplete emptying of the bladder;
  • loss of bladder control (urinary incontinence);
  • a feeling of pressure or pain in the lower abdomen or pelvis;
  • foul odor to the urine;
  • urine that is milky, cloudy, reddish, or dark in color;
  • blood in the urine;
  • back pain, flank (side) pain, or groin pain;
  • fever or chills;
  • pain during sexual intercourse;
  • fatigue;
  • general feeling of being unwell (malaise);
  • vaginal irritation; and
  • in elderly patients, subtle symptoms such as altered mental status (confusion) or decreased activity may be signs of a UTI.

Vaginal itching is not a typical symptom of a UTI. It may be a sign of bacterial vaginosis or a vaginal yeast infection.

If one is experiencing fever or back pain, this may be a sign of a kidney infection (pyelonephritis), which can be a serious medical issue. Seek medical attention immediately.

Urinary Tract Infection (UTI) Causes

When bacteria enter into the urinary tract, this can result in an infection. Escherichia coli (E. coli) is the bacteria that causes the vast majority of UTIs. However, other bacterial pathogens can also cause UTIs. A urine culture can help isolate the bacteria responsible for a particular UTI.

Urinary tract infections are not considered to be contagious, and you can't acquire a UTI from someone else.

Urinary Tract Infection (UTI) Symptoms, Diagnosis, Medication Slideshow

Urinary Tract Infection (UTI) Symptoms, Diagnosis, Medication Slideshow

Urinary tract infection (UTI) symptoms can be frightening and a cause for concern. Some people who have a UTI don't have any symptoms. Sometimes a doctor may diagnose a UTI based on the description of the patient's symptoms and ruling out other potential causes. The following slides describe common symptoms of a UTI.


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