RESEARCH ARTICLE Performance of a Novel Molecular Method in the Diagnosis of Late-Onset Sepsis in Very Low Birth Weight Infants

Objective To compare the use of a generic molecular assay to ‘standard ’ investigations used to assist the diagnosis of late onset bacterial sepsis in very low birth weight infants (VLBW, <1500g). Methods VLBW infants, greater than 48 hours of age, who were clinically suspected to have sepsis were investigated using standard tests (full blood count, C-reactive protein (at presentation) and blood culture), in addition, blood was taken for a universal molecular assay (16S rRNA reverse transcriptase PCR) for comparison. Clinical data were recorded during the sus-pected infection episode. A validated sepsis score (NEO-KISS) was used to retrospectively determine the presence of sepsis (independent of blood culture). The performance of each of the tests were compared by sensitivity, specificity, positive/negative likihood ratios (+/-LR) and postive/negative predictive values (PPV/NPV). Results Sixty-five babies with suspected clinical sepsis were prospectively included. The perfor-mance indicators are presented with 95 % confidence limits. For the detection of bacteria, blood culture had sensitivity of 0.57 (0.34–0.78), specificity of 0.45 (0.30–0.61); +LR of 1.0