Usefulness of the Combination of FilmArray and procalcitonin in respiratory infections in the Pediatric Intensive Care Unit

Abstract

Introduction. Acute respiratory infections represent one of the main causes of preventable infant mortality and morbidity in children, and although a significate proportion of cases are of viral etiology, antibiotic treatment is the overly-excessive norm. Studies suggest that the combined use of serum procalcitonin (PCT) and polymerase chain reaction (PCR) multiplex (FilmArray) may be used to guide antibiotic therapy. Methods. A prospective cohort study was conducted of patients between 1 month and 17 years of age with acute respiratory infection hospitalized in the PICU with a negative viral panel report and both respiratory FilmArray and procalcitonin performed in the first 72 hours of hospitalization. A diagnostic algorithm was then applied to these patients, tailored to the result of both tests. Results. Of the total 326 patients recluted, 110 met the inclusion criteria; 23 patients were excluded for infections other than respiratory origin. Of the 87 remaining patients, all had a respiratory FilmArray performed prior to the PCT sample, demonstrating a diagnostic yield of over 80%. Procalcitonin was requested in slightly more than half of the patients and was positive in a third of these cases. When combined in the diagnostic algorithm, FilmAray and PCT lead to changes in treatment plan in 30% of patients in terms of antibiotic management prescribed on admission, with the most frequent treatment plan change being suspending the antibiotic altogether (from 41.4% to 10.3%, for a total of 89.7% of patients without antibiotic therapy following the algorithm. None of the patients died and only 1/87 patients required re-initiating antibiotics after having suspended treatment. The interaction between the identification of a viral pathogen in the FilmArray and a negative PCT result yielded statistically significant results (p=0.004) and affected the change in treatment management mainly in antibiotic discontinuation.Conclusions. The combined use of FilmArray and serum PCT as tools in the diagnostic algorithm is a safe way to guide tailored antibiotic therapy in pediatric patients with ARI in critical state.