Procalcitonin performance in detecting serious and invasive bacterial infections in children with fever without apparent source: a systematic review and meta-analysis

<b>Introduction</b>: The management of children with fever without apparent sources (FWAS) is difficult. This study aimed to evaluate the diagnostic accuracy of procalcitonin (PCT) in detecting serious or invasive bacterial infection (SBI or IBI) in children with FWAS. <b>Areas covered</b>: A systematic review of literature from 2007 to 2017 was performed on Medline. Twelve studies were included, involving 7,260 children with FWAS and analyzing the diagnostic performance of PCT. Four meta-analyses were performed to calculate pooled sensitivity, specificity, diagnostic odds ratio, and summary receiver operating characteristic curve for PCT in detecting SBI and IBI, at two different thresholds. Considering IBI, PCT sensitivity and specificity at a threshold of 0.5 ng/mL were 0.82 and 0.86, respectively; at a threshold of 2 ng/mL sensitivity and specificity were 0.61 and 0.94, respectively. In detecting SBI, PCT performance was lower, with 55% sensitivity and 85% specificity at a threshold of 0.5 ng/mL, and 30% sensitivity and 95% specificity at a threshold of 2 ng/mL. <b>Expert commentary</b>: Considering IBI, results showed high diagnostic accuracy for PCT. Conversely, PCT performance in diagnosis of SBI was poor. These findings suggest that PCT level determination could be helpful in detecting meningitis, bacteremia and sepsis in children with FWAS.