Pilot Study of a New Mathematical Algorithm for Early Detection of Late-Onset Sepsis in Very Low-Birth-Weight Infants

Abstract

Diagnosis of late onset sepsis (LOS) in very low birth weight (VLBW) preterm infants relies mainly on clinical suspicion, whereas prognosis depends on early initiation of antibiotic treatment. RALIS is a mathematical algorithm for early detection of LOS incorporating six vital signs measured every 2 hours. The aim of this study is to study RALIS ability to detect LOS before clinical suspicion. A total of 118 VLBW preterm infants (gestational age < 33 weeks, birth weight < 1,500 g) were enrolled in a prospective multicentered study. Vital signs were recorded prospectively up to day 21 of life in a blinded manner, with no effect on standard care. The primary end point was comparison of the rates and timing of detection of LOS between RALIS and clinical/culture evidence of LOS. Of the 2,174 monitoring days, RALIS indicated sepsis in 590 days, and LOS was positively diagnosed in 229 days. Sensitivity, specificity, positive, and negative predictive values were 74.6, 80.7, 38.8, and 95.1%, respectively. RALIS provided an indication for sepsis 3 days on the average before clinical suspicion. RALIS has a promising potential as an easy to implement noninvasive early indicator of LOS, especially for ruling out LOS in VLBW high-risk infants.