What does pain in the side mean?
Pain in the side or flank is usually located between the lower edge of the ribs and the hip. It can be felt superficially in the muscles or deeper within the body.
It is not possible to determine that the pain is coming from the kidney based on its location alone. The kidneys are located high and deep, and several other structures can cause similar discomfort.
Read also about kidney pain and kidneys and urinary tract.
Common causes of side pain
Kidney stones can cause sudden, very severe, wave-like pain that radiates to the lower abdomen or groin. Nausea and blood in the urine may occur.
Pelvic inflammatory disease often causes fever, malaise, and pain in the side or back along with urinary tract symptoms. This requires antibiotic evaluation.
Muscle strains, rib problems, coughing, and overexertion can cause pain that is affected by movement or pressure. The intestines, biliary tract, and other abdominal organs can also cause pain in the side.
When should side pain be assessed quickly?
Seek medical attention promptly if you have flank pain with fever, chills, poor general condition, or difficulty urinating. Infection combined with urinary tract obstruction can be serious.
Urgent assessment is needed in the event of very severe pain that does not go away, fainting, cold sweats, a hard abdomen, bloody vomiting or stools, and a rapidly deteriorating condition.
Contact healthcare if there is blood in the urine, recurrent attacks, unexplained weight loss or a lump in the abdomen, even if the pain is moderate.
Seek medical attention on the same day if you have a fever and pain in your side, especially if you also have urinary problems or feel clearly ill.
How is pain in the side investigated?
The healthcare provider asks about onset, radiation, movement, fever, stool and urine. The abdomen, back, ribs and the area above the kidneys are examined.
Urine tests can show blood or infection. Blood tests can assess infection, kidney function, and other organ involvement.
Pregnancy, previous stones, surgeries, medications, and only one functioning kidney affect how quickly and with what method the investigation is done.
When is ultrasound, CT or MRI used?
Ultrasound can show dilated urinary tracts, some stones, and several abdominal organs without ionizing radiation. It is often used in pregnancy and in other selected situations.
CT without contrast is often used for acute suspected kidney stones because the method is fast and sensitive for stones. CT with contrast can be used for other abdominal issues.
MRI abdomen used for specific soft tissue and organ issues but is not a common first-line method for acute kidney stone attacks.
What can you follow before a scheduled assessment?
Note whether the pain is affected by movement, breathing, eating or going to the bathroom. Monitor temperature and urine color.
Drink normally if you can, but do not try to force large amounts of fluid down your throat if you are experiencing severe pain or vomiting. This will not treat a possible blockage.
Do not take repeated high doses of painkillers without medical advice, especially if kidney function may be affected.