Urinary Tract Infection - Diagnosis

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Bladder Cancer. Bladder cancer is a rare cause of painful urination and is more common in men than in women.

Kidney Stones. The pain of kidney stones along with blood in the urine can resemble the symptoms of pyelonephritis. There are no bacteria present with kidney stones, however.

Thinning Urethral and Vaginal Walls. After menopause, the vaginal and urethral walls become dry and fragile causing pain and irritation that can mimic a UTI.

Disorders in Children that Mimic UTIs. Problems that might cause painful urination in children include reactions to chemicals in bubble bath, diaper rashes, and infection from the pinworm parasite.

Prostate Conditions in Men. Prostate conditions, including prostatitis (inflammation of the prostate) and benign prostatic hyperplasia, can cause symptoms similar to urinary tract infections.

Click the icon to see an image of benign prostatic hypertrophy.

Physical Examination

During an exam, the doctor should examine the pelvic and vaginal area in women. Men require a digital rectal examination to determine if prostate enlargement is present. The doctor will also examine the male genitals for signs of infection. In both men and women, the doctor should also check the abdomen and areas around the kidneys for swelling and tenderness.

Dipstick Tests

Dipstick tests, available over the counter, are quite reliable in making a reasonable diagnosis of UTIs in women with symptoms. Dipstick tests may also be useful for identifying UTIs in children and infants. The test uses a chemical on a stick that when dipped in urine reacts to nitrites, substances produced by many of the bacteria that cause UTIs. A positive test (which indicates that an infection is present) often eliminates the need urine cultures, a more expensive test used for detecting bacteria. A negative dipstick test helps to avoid unnecessary antibiotics, which are contributing to the growing problem of antibiotic resistance. These tests are not entirely accurate, however, and studies report that they may miss up to 25% of actual UTIs. If a woman has persistent UTI symptoms and the dipstick test is negative, she should check with her doctor to see if more accurate tests are needed.

Urine Samples

A urine sample is needed for most extensive testing. In most cases, the doctor requests a clean-catch sample. There are also other methods for collecting urine depending on the patient's condition.

Clean-Catch Sample. A clean-catch sample for UTI depends on a sample free of contaminants normally present at the opening of the urethra (white blood cells and bacteria unrelated to UTIs). To obtain an untainted urine sample, doctors usually request a so-called midstream, or clean-catch, urine sample. To provide this, the following steps are taken: