CKS is no longer commissioned by the National Institute for Health and Clinical Excellence (NICE). NICE remains committed to providing a replacement service for CKS and is currently reviewing its options. In the meantime, although CKS content is now not being maintained, it still remains relevant and will continue to be made available. CKS content was generated under a programme of topic creation and update. To check if the topic you are viewing is current or out of date, please refer to the topic publication details by clicking on the 'How up-to-date is this topic?' link in the left hand menu on individual topic pages.
Pyelonephritis - acute - Management
How do I diagnose acute pyelonephritis?
- Acute pyelonephritis is diagnosed in a person with a proven urinary tract infection who has loin pain and/or fever. There are no clinical features or routine investigations that conclusively distinguish acute pyelonephritis from cystitis.
- Suspect acute pyelonephritis in people with loin pain and/or fever.
- Dipstick test the urine for leucocyte esterase and nitrite for evidence of a urinary tract infection (UTI). For further information, see Dipstick testing.
- If both dipstick tests are negative, a UTI is unlikely.
- If the leucocyte esterase test alone is positive, a UTI is moderately likely.
- If the nitrite test is positive, with or without a positive leucocyte esterase test, a UTI is highly likely.
- Consider and exclude other causes of loin pain and/or fever (particularly if both dipstick tests are negative) including:
- Pelvic inflammatory disease.
- Appendicitis.
- Renal calculi.
- Send a midstream (or catheter) specimen of urine for culture and sensitivity.
- A final diagnosis of acute pyelonephritis is made in people with loin pain and/or fever if:
- A UTI is confirmed by culturing a urinary pathogen from the urine, and
- Other causes for symptoms have been excluded.
© NHS Institute for Innovation and Improvement