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Kidney Infection (Pyelonephritis)

A kidney infection occurs when bacteria travel from the bladder up the ureters and into the kidneys. Sometimes kidney infections may occur when bacteria in the blood enter the kidneys.

Symptoms of kidney infection may include:

  • Painful urination and other symptoms of a bladder infection.
  • Pain in the flank, which is felt just below the rib cage and above the waist on one or both sides of the back.
  • Fever.
  • Nausea and vomiting.

Oral antibiotics usually can treat kidney infections. But a brief hospital stay and a short course of intravenous (IV) antibiotics are sometimes required. If not treated with antibiotics, the infection may damage the kidneys. The infection may also spread to the bloodstream and become life-threatening, especially in young children and the elderly.

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerAvery L. Seifert, MD - Urology
Last RevisedMay 13, 2013

WebMD Medical Reference from Healthwise

Last Updated: May 13, 2013
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.