Emergency department presentation of the pediatric systemic inflammatory response syndrome

The epidemiology of the systemic inflammatory response syndrome (SIRS) in children is poorly understood. We sought to determine national estimates of the incidence of pediatric SIRS and its corresponding clinical etiologies presenting to US emergency departments (EDs) using current definitions.

We analyzed ED visits by children younger than 18 years from 2007 to 2010 in the National Hospital Ambulatory Medical Care Survey. We used a Bayesian logical framework of prior probability distributions for white blood cell count result to make minimum, moderate, and maximum estimates for pediatric SIRS.

Taking the minimum and maximum estimates as modified credible intervals, we report an overall incidence of pediatric SIRS presenting to the ED to be 21.7% (95% modified credible interval, 18.1%-25.4%). The national moderate estimate of pediatric ED visits presenting with SIRS was approximately 6.2 million per year. Children with SIRS and without SIRS had similar baseline characteristics, but SIRS patients were younger (2.9 vs 5.5 years; P < 0.0001), had higher triage acuity (emergent, 9.0 vs 6.3%; P < 0.0001), and were more often admitted (7.0 vs 2.4%; P < 0.0001) than children without SIRS. Based on the moderate estimate, infection was the most common (53%) associated etiology, followed by trauma (10%). Other traditional categories of SIRS were extremely rare. Of note, 35% of children with SIRS did not fall into any of the previously established categories.

Pediatric SIRS is common; its associated clinical contexts include potentially dangerous etiologies; many cases of pediatric SIRS can be recognized in triage; and there is significant heterogeneity in the etiology of pediatric SIRS.