Symptoms of Kidney Stones
Classic Presentation
The hallmark symptom of kidney stones is sudden onset of severe unilateral flank pain that radiates from the loin to the groin or external genitalia. 1, 2, 3
- Pain onset is abrupt and severe, often described as one of the most intense pain experiences patients report 4, 5
- The pain is typically unilateral and follows a characteristic radiation pattern depending on stone location 6, 3
Pain Characteristics by Stone Location
Stone location determines the specific pain pattern and radiation:
- Renal pelvic or upper ureteric stones cause predominantly flank pain and tenderness in the costovertebral angle 4
- Lower ureteric stones produce pain radiating toward the ipsilateral testicle in men or labia in women 4
- Pain severity depends on the degree of ureteral obstruction and individual pain threshold, not necessarily stone size 7
Associated Urinary Symptoms
Hematuria is present in over 80% of patients with acute renal colic and serves as an important diagnostic clue. 3, 4
- Irritative lower urinary tract symptoms including dysuria, frequency, and urgency commonly occur 4, 8
- Patients may notice changes in urine color or volume 3
Gastrointestinal Symptoms
Nausea and vomiting accompany the pain in approximately 50% of cases due to shared visceral innervation. 1, 7
- These symptoms result from ureteral hyperperistalsis and autonomic nervous system activation 6
- Severe cases may lead to hypotension and syncope 7
Critical Red Flag Symptoms Requiring Immediate Evaluation
Fever with flank pain indicates possible obstructive pyelonephritis—a urologic emergency requiring urgent decompression. 1, 2, 4
- Signs of systemic infection or septic shock mandate immediate hospital admission 1, 4
- Anuria with obstruction suggests bilateral obstruction or obstruction in a solitary kidney 1
- Uncontrolled pain despite adequate analgesia within 60 minutes requires emergency referral 1, 2
Important Diagnostic Caveats
In patients over 60 years presenting with flank pain, always consider leaking abdominal aortic aneurysm as a life-threatening alternative diagnosis. 1, 2, 3
- Women of childbearing age with delayed menses require evaluation for ectopic pregnancy 1, 2, 3
- Signs of peritonitis on abdominal examination suggest alternative intra-abdominal pathology 1, 2
Diagnostic Confirmation
The combination of symptoms suggestive of renal colic plus positive urine dipstick for hematuria has 84% sensitivity and 99% specificity for stone disease. 4
- However, absence of hematuria does not exclude the diagnosis 6
- Noncontrast CT has 97% sensitivity and is considered the reference standard for confirming urolithiasis 6, 9
Common Pitfall to Avoid
Never delay analgesia while waiting for diagnostic imaging—pain control should begin immediately when renal colic is clinically suspected. 1, 2