Changes in equine complete blood count parameters and inflammatory indices with inflammation.
Authors: Friend M M, McGaffigan E M, Hall S M, Staniar W B, Smarsh D N
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Early identification of systemic inflammation in horses remains clinically challenging, yet timely detection could prevent progression to serious disease. Friend and colleagues conducted an observational study of 199 horses (48 with documented inflammation, 151 clinically healthy) to evaluate whether complete blood count parameters and newly calculated inflammatory indices could reliably predict inflammatory status, using serum amyloid A and haptoglobin concentrations as gold-standard markers. Three inflammatory indices—the systemic inflammation index (SII), systemic inflammation response index (SIRI), and age-adjusted systemic inflammation index (AISI)—demonstrated superior predictive value (AUC 0.64–0.66) compared with standard CBC parameters, with horses exhibiting values outside normal ranges being 4.5 to 7 times more likely to be systemically inflamed; crucially, reference intervals derived from non-inflamed horses outperformed industry-standard intervals in detecting inflammation. These findings suggest that incorporating inflammatory indices into routine bloodwork protocols could provide farriers, veterinarians, and other practitioners with a practical, accessible screening tool for identifying subclinical inflammation before clinical signs become apparent, potentially enabling earlier intervention and improved health outcomes.
Read the full abstract on PubMed
Practical Takeaways
- •Inflammatory indices (SII, SIRI, AISI) derived from routine CBC offer modest but practical improvement over standard parameters for detecting systemic inflammation in clinical horses
- •Using reference intervals established from known non-inflamed horses rather than standard industry ranges may improve your ability to identify subtle inflammatory states earlier
- •Combined assessment across all three inflammatory indices appears more reliable than any single parameter for flagging inflammation in practice
Key Findings
- •All three inflammatory indices (SII, SIRI, AISI) showed greater median values in inflamed horses with predictive value (AUC 0.64–0.66) superior to all other CBC parameters tested
- •Horses with values outside all three inflammatory index reference intervals were 4.54–7 times more likely to be classified as inflamed
- •Non-inflamed reference intervals derived from healthy horses showed greater diagnostic utility for detecting inflammation than industry standard reference intervals