Laboratory evaluation for pediatric patients with suspected necrotizing soft tissue infections: A case-control study.

Background/purpose: Optimal outcomes for necrotizing soft tissue infections (NSTI) depend on rapid diagnosis and management. The Laboratory Risk Indicator for Necrotizing Fasciitis (LRINEC) score is a validated diagnostic tool for adult NSTI, but its value for children remains unknown. We hypothesized that modification of the LRINEC score may increase its diagnostic accuracy for pediatric NSTI.

Methods: We performed a case-control study of pediatric patients (age <18) with NSTI (cases) and patients with severe soft tissue infections prompting surgical consultation (controls). The LRINEC score was calculated for cases and controls and compared to a modified, pediatric LRINEC (P-LRINEC) score. Diagnostic accuracy was analyzed through receiver operating characteristic (ROC) curves.

Results: From 2010 to 2014, 20 cases and 20 controls were identified at two children's hospitals. Median LRINEC score was 3.5 (1-8) for cases and 2 (1-7) for controls (p=0.03). The P-LRINEC was comprised of serum CRP >20 (sensitivity=95% (95%CI 79-100%)) and serum sodium <135 (specificity=95% (95%CI 82-100%)). Area under ROC curves was 0.70 (95%CI 0.54-0.87) for the LRINEC score and 0.84 (95%CI 0.72-0.96) for the P-LRINEC score (p=0.06).

Conclusion: The P-LRINEC is a simplified version of the LRINEC score utilizing only CRP and sodium and may provide superior accuracy in predicting pediatric NSTI.