MedDroidKidney Stone vs UTI
Kidney stone vs UTI: differences in symptoms, tests and treatment
Written & medically reviewed by Dr. Sanjay Anbu, MBBS · Last reviewed
Medically reviewedA kidney stone is a hard crystal that can block urine flow and cause severe, wave-like pain in the side or back that spreads to the groin. A UTI (urinary tract infection) is a bacterial infection that usually causes burning while urinating, urgency and lower belly discomfort. The two can happen together, and fever with side pain and a stone is an emergency.
Side-by-side comparison
| Feature | Kidney stone | UTI |
|---|---|---|
| Cause | Crystals (often calcium) form in the kidney; low water intake, hot climate, diet, family history, some medical conditions | Bacteria (usually E. coli) entering the urinary tract; more common in women, during pregnancy, with diabetes |
| Typical symptoms | Sudden severe pain in the side or back coming in waves, spreading to lower belly or groin; nausea, vomiting, blood in urine, restlessness | Burning while passing urine, frequent urge, passing small amounts, cloudy or smelly urine, lower belly pain; fever if kidney is involved |
| Onset & timing | Sudden, when the stone moves | Over hours to a day or two |
| Key tests | Urine test (blood), ultrasound or CT KUB scan, kidney function, calcium and uric acid | Urine routine and urine culture; kidney function and ultrasound if severe or recurrent |
| Treatment approach | Pain relief, fluids, medicines to help the stone pass; procedures (lithotripsy, ureteroscopy) for large or stuck stones | Antibiotics chosen by a doctor, ideally guided by urine culture; fluids |
| Danger signs | Stone plus fever or chills (infected blocked kidney), no urine, uncontrolled pain or vomiting | Fever, chills, back or side pain, vomiting (kidney infection), confusion in older adults |
General patterns only. Symptoms overlap and vary from person to person. On a phone, scroll the table sideways to see both columns.
How doctors tell them apart
- Pain pattern: colicky side pain spreading to the groin suggests a stone; burning on urination suggests UTI.
- Urine test: blood without infection points to stone; white cells and bacteria point to UTI.
- Ultrasound or CT shows a stone and any blockage.
- Urine culture identifies the bacteria and which antibiotics work.
See a doctor urgently if
- Fever or chills with side or back pain
- Unable to pass urine, or very little urine
- Pain that is not controlled, or vomiting that prevents drinking
- UTI symptoms in pregnancy, in a child, or in a man
- Confusion or extreme weakness in an older person
In an emergency, call your local emergency number (in India: 108 or 112).
Frequently asked questions
Can a kidney stone cause a UTI?
Yes. Stones can trap bacteria and block urine flow, raising infection risk. A blocked, infected kidney needs urgent treatment.
How much water should I drink to prevent stones?
Enough to keep urine pale throughout the day; doctors often suggest aiming for a good daily urine output. Your needs depend on climate and health, so ask your doctor.
Should I take leftover antibiotics for a UTI?
No. The wrong antibiotic can fail and encourage resistance. See a doctor and get a urine test.
Do all stones need surgery?
No. Many small stones pass on their own with fluids and medicines. Larger or stuck stones may need a procedure.
Related pages
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Symptoms
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Not a diagnosis. This page gives general health information to help you talk to a doctor; it is not medical advice and does not replace an examination or tests. Do not start, stop or change any medicine without a qualified clinician. MedDroid is an AI medical assistant and can make mistakes. In an emergency, call your local emergency number (in India: 108 or 112).