What are the symptoms of kidney infection?

A kidney infection affects the upper urinary tract and may cause a person to feel suddenly ill. Fever or chills may occur with pain in the flank, back or under the ribs. Urination can sting, become more frequent or feel urgent, and urine may look cloudy, smell differently or contain blood. Nausea and vomiting can make drinking difficult. A urinary tract infection can sometimes spread upwards, but similar symptoms may have other causes, including a stone or another illness. Symptoms alone cannot confirm the diagnosis.

Contact a clinician promptly if these symptoms suggest a kidney infection, especially if fever is present with flank pain or urinary symptoms. The assessment may include an examination and a urine test to look for infection. Take prescribed antibiotic treatment exactly as directed; do not use leftover antibiotics. Sip fluids if you can keep them down, rest, and keep track of fever, pain, vomiting and changes in urine while arranging care.

Seek urgent medical help for severe or worsening flank pain, repeated vomiting, confusion, faintness, breathing difficulty, inability to pass urine, or feeling severely unwell. Urgent assessment is also needed during pregnancy, in a child, or when a person has significant kidney problems or a weakened immune system. Blood in urine with fever or side pain should not be ignored. A kidney infection can worsen without timely treatment.

Could this be a kidney infection, a urinary tract infection or a stone? Do I need a urine test or other assessment? Which antibiotic treatment is suitable for me? What should I do if vomiting prevents me from taking medicine or fluids?