How common is flank pain in kidney infection?

A kidney infection affects the upper urinary tract and can cause aching or tenderness in the back or side beneath the ribs. The discomfort may stay on one side, feel deep, or worsen when the area is touched. Burning urination, needing to pass urine often, cloudy urine, fever, chills, nausea, or feeling generally unwell can occur alongside it. Flank pain can also have other causes, so its presence alone does not establish the diagnosis.

Arrange prompt medical assessment if flank pain occurs with fever, chills, vomiting, or urinary changes. A clinician may ask when the pain began, examine your abdomen and back, and test a urine sample. Take prescribed treatment exactly as directed and drink fluids if you can keep them down. Do not delay assessment because symptoms can worsen when an infection reaches the kidneys.

Seek urgent care for severe or rapidly worsening pain, confusion, faintness, repeated vomiting, trouble keeping fluids down, or marked weakness. Pregnancy, childhood, older age, a weakened immune system, kidney disease, or difficulty passing urine warrants a lower threshold for same-day advice. A very high fever with shaking chills also needs prompt attention.

Ask whether your symptoms fit a kidney infection, which tests are needed, how soon treatment should help, and what warning signs should send you back for review. Mention previous urine infections, medicines, allergies, pregnancy, and any history of kidney problems.