Kidney infection (pyelonephritis)

Overview Symptoms Treatment Prevention

Alternative Names:

Urinary tract infection - complicated; Infection - kidney; Complicated urinary tract infection; Pyelonephritis

Symptoms:

Flank pain or back pain
Severe abdominal pain (occurs occasionally)
Fever
- Higher than 102 degrees Fahrenheit
- Persists for more than 2 days
Chills with shaking
Warm skin
Flushed or reddened skin
Moist skin (diaphoresis)
Vomiting, nausea
Fatigue
General ill feeling
Urination, painful
Urinary frequency/urgency, increased
Need to urinate at night (nocturia)
Cloudy or abnormal urine color
Blood in the urine
Foul or strong urine odor
Mental changes or confusion *

* Sometimes in the elderly, mental changes or confusion are the only signs of a urinary tract infection.

Signs and tests:

An examination may show tenderness on palpation (pressing) over the kidney.

A urinalysis commonly reveals white blood cells (WBCs) and/or red blood cells (RBCs).
A urine culture (clean catch) or urine culture (catheterized specimen) may reveal bacteria in the urine.
A blood culture may show an infection.
An intravenous pyelogram (IVP) or CT scan of the abdomen may show enlarged kidney(s) with poor flow of dye through the kidneys. (IVP and CT scan of the abdomen can also indicate underlying disorders.)

Underlying abnormalities of the kidney predisposing a patient to acute pyelonephritis may be discovered by additional other tests and procedures, including the following: