Pyelonephritis (pie-low-ne-FRY-tis) is an infection in one or both kidneys. Pyelonephritis happens when urine (pee) infected with bacteria flows up from the bladder or when an infection in the bloodstream reaches the kidneys.
A kidney infection like pyelonephritis is similar to a bladder infection, as they are both urinary tract infections (UTIs). However, children are usually sicker with fever, back pain, or vomiting with pyelonephritis.
Pyelonephritis requires medical attention. A doctor will ask for a urine sample, and may order other tests, to determine the cause and best treatment. It's important to treat kidney infections with a full course of antibiotics. Untreated and repeat infections can lead to high blood pressure and kidney disease in adulthood.
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