Can flank pain be a symptom of kidney stones in a patient with a history of kidney stones or other underlying medical conditions?

Flank Pain and Kidney Stones

Yes, flank pain is a common and characteristic presenting symptom of kidney stones (urolithiasis), occurring due to ureteral hyperperistalsis and obstruction caused by the stone. 1

Clinical Presentation

Flank pain from kidney stones has specific characteristics:

• The pain is typically colicky in nature, with waves of severe pain alternating with periods of less intense discomfort 2
• Pain results from internal obstruction and distension of the collecting system, not from external pressure 2
• Importantly, nephrolithiasis pain does not worsen with external flank pressure—if pain significantly worsens with palpation, consider alternative diagnoses such as pyelonephritis, kidney infection, or perinephric abscess 2
• Associated symptoms may include hematuria (from ureteral irritation and trauma), dysuria, urinary frequency, fever, and groin pain 1, 3

Epidemiology and Risk Factors in Patients with History

Patients with a history of kidney stones face high recurrence rates:

• By age 70, approximately 19% of men and 9% of women will be diagnosed with a kidney stone 1
• Recurrence rates are significantly higher in those with 2 or more previous stone episodes 1
• Risk factors include renal/ureteral anatomic abnormalities, family history, obesity, metabolic syndrome, diabetes, and hypertension 3

Important Diagnostic Considerations

When evaluating flank pain in patients with stone history:

• Non-contrast CT is the gold standard for diagnosing urolithiasis, with sensitivity as high as 97% 1, 2
• In patients with known current stone disease presenting with recurrent symptoms, assess for interval stone migration, passage, or complications (infection, perinephric abscess, urinoma) 1
• Ultrasound combined with radiography offers 79-90% sensitivity and is useful for detecting clinically significant stones, particularly when radiation exposure is a concern 2

Critical Pitfalls to Avoid

Do not anchor solely on nephrolithiasis:

• While flank pain with hematuria commonly suggests kidney stones, other serious conditions can present identically, including Page kidney (subcapsular hematoma causing secondary hypertension), renal tumors, and vascular abnormalities 4
• Evaluate for complications requiring urgent intervention: signs of infection (fever, elevated CRP/WBC), impaired renal function, anuria, or bilateral obstruction 5
• If sepsis and/or anuria are present, urgent decompression via percutaneous nephrostomy or ureteral stenting is mandatory before definitive stone treatment 5

Stone Location and Pain

Even nonobstructing stones can cause significant pain:

• Recent evidence demonstrates that nonobstructing calyceal kidney stones can cause moderate to severe flank pain 6
• Surgical removal of these stones results in significant pain reduction (86% of patients had ≥20% reduction in pain scores) and improved quality of life at 12 weeks postoperatively 6
• Stone size and location are important determinants of spontaneous passage, with larger and more proximally located stones having lower passage rates 1, 2

Management Implications

For patients with flank pain and suspected stones:

• Stones ≥10mm will not pass spontaneously and require surgical intervention 5
• Medical expulsive therapy is first-line for uncomplicated distal ureteral stones ≤10mm 3
• Pain control with NSAIDs (diclofenac, ibuprofen, or metamizole) is preferred over opioids as first-line therapy 5