If you feel sick around your lower back or notice a sudden change in how you pee, it could be more than a regular urinary tract infection. A kidney infection, also called pyelonephritis, hits the kidneys and can make you feel really rough fast. Knowing the signs early helps you get treatment before the illness spreads.
Most people notice a strong pain in one side of the back or flank, right under the ribs. The pain can be sharp or dull, but it usually doesn’t go away on its own. Along with the ache, you’ll probably have a fever of 100.4°F (38°C) or higher, and you might feel chills or sweat a lot.
Urine changes are another big clue. Expect cloudy or foul‑smelling pee, sometimes with a pink or brown tint because of blood. Burning when you urinate, a frequent urge to go, or feeling like you can’t finish emptying your bladder are also common.
Other symptoms include nausea, loss of appetite, and sometimes vomiting. Your body is fighting an infection, so you may feel unusually tired or weak. If you have any of these together—back pain, fever, and urinary changes—it’s a good idea to think kidney infection.
Not all kidney infections stay mild. Watch for a higher fever that won’t drop with over‑the‑counter meds, or pain that spreads to the abdomen or groin. If you start to feel confused, have a rapid heartbeat, or notice a sudden drop in urine output, seek medical help right away.
Complications like a kidney abscess or sepsis can develop if the infection isn’t treated. These situations need hospital care and strong antibiotics. Don’t wait for the pain to get unbearable—early treatment usually clears the infection in a week.
To confirm the diagnosis, doctors often do a urine test and may order a blood test or imaging scan. The samples show the bacteria causing the problem, which guides the right antibiotic choice.
While you’re waiting for an appointment, drink plenty of water (unless your doctor says otherwise) to help flush bacteria out. Over‑the‑counter pain relievers like acetaminophen can lower fever, but avoid ibuprofen if you have kidney issues unless told otherwise.
Preventing future infections means staying hydrated, wiping front to back, and urinating after sex. If you’ve had kidney infections before, talk to your doctor about a possible low‑dose antibiotic plan.
Bottom line: kidney infection symptoms are a mix of back pain, fever, and urine changes. Spotting them early and getting proper care stops the infection from turning dangerous. Keep an eye on your body, and don’t hesitate to call a health professional if the signs stack up.
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