Will white blood cell count (WBC) elevate with renal stones?

Elevated White Blood Cell Count in Renal Stone Disease

Yes, white blood cell count (WBC) can elevate with renal stones, especially when there is associated infection or inflammation. According to clinical guidelines, people with ADPKD who present with fever, acute abdominal or flank pain, and an increased white blood cell count should undergo workup for kidney cyst infection 1.

Relationship Between WBC and Renal Stones

• An elevated WBC count is commonly seen in patients with renal stones, particularly when there is associated infection or inflammation 1, 2
• WBC elevation is one of the diagnostic features considered when evaluating patients with renal stone disease, with values >11 × 10^9/L being significant 1
• Increased WBC count, along with elevated C-reactive protein levels, may indicate complications such as infection associated with renal stones 1

Clinical Significance of WBC Elevation

• WBC elevation in renal stone patients may indicate:

  • Urinary tract infection secondary to obstruction 1
  • Inflammatory response to the stone itself 2, 3
  • Possible sepsis in cases of complete obstruction 1

• In patients with obstructing urinary stones and sepsis, urgent decompression is necessary, and WBC count is one of the parameters monitored to assess response to treatment 1

WBC as a Diagnostic Marker

• An increase in WBC, particularly granulocyte percentage, is statistically associated with urinary stone disease 3
• Interestingly, some studies have found that increased WBC and neutrophil counts at the time of acute renal colic may actually be associated with increased likelihood of spontaneous stone passage 4
• WBC count alone is not sufficient for diagnosis of renal stone disease but serves as a supporting laboratory finding when evaluated alongside imaging and clinical presentation 3

Monitoring and Management

• In patients with suspected renal stone disease, a complete blood count with differential should be performed, especially if infection is suspected 1, 2
• For patients with obstructing stones and elevated WBC suggesting infection, urgent intervention may be required to relieve obstruction and prevent sepsis 1
• Following intervention for infected obstructing stones, normalization of WBC count is one parameter used to assess treatment success 1

Important Considerations

• Not all patients with renal stones will have elevated WBC counts; absence of leukocytosis does not rule out stone disease 5
• WBC elevation should be interpreted in the context of other clinical findings such as fever, flank pain, and urinalysis results 2, 6
• Stone size and location are more significant predictors of stone passage than WBC count 5
• Microscopic hematuria has a much stronger association with urinary stone disease than WBC elevation 3

When to Be Concerned

• WBC count >14,000 cells/mm³ warrants careful assessment for bacterial infection, even without fever 2, 6
• Left shift (≥16% band neutrophils or band neutrophil count ≥1,500 cells/mm³) is highly suggestive of bacterial infection, with a likelihood ratio of 14.5 2, 6
• Persistent or worsening WBC elevation despite appropriate treatment may indicate complications requiring further intervention 1

Remember that while WBC elevation can occur with renal stones, it's most significant when associated with infection or obstruction, and management decisions should be based on the complete clinical picture rather than WBC count alone.