Efficacy of bacterial ribosomal RNA-targeted reverse transcription-quantitative PCR for detecting neonatal sepsis: a case control study

Subjects comprised 36 patients with 39 episodes of suspected neonatal sepsis who underwent BrRNA-RT-qPCR and conventional blood culture to diagnose sepsis. Blood samples were collected aseptically for BrRNA-RT-qPCR and blood culture at the time of initial sepsis evaluation by arterial puncture. BrRNA-RT-qPCR and blood culture were undertaken using identical blood samples, and BrRNA-RT-qPCR was performed using 12 primer sets.Positive rate was significantly higher for BrRNA-RT-qPCR (15/39, 38.5%) than for blood culture (6/39, 15.4%; p = 0.0039). BrRNA-RT-qPCR was able to identify all pathogens detected by blood culture. Furthermore, this method detected pathogens from neonates with clinical sepsis in whom pathogens was not detected by culture methods.This RT-PCR technique is useful for sensitive detection of pathogens causing neonatal sepsis, even in cases with negative results by blood culture.The incidence of sepsis is higher in neonates than in adult patients, and the risk of mortality is higher [1]. In particular, neonates with low birth weight show relatively high morbidity and mortality [2-4]. Furthermore, neonatal sepsis is difficult to diagnose, as clinical signs are often obscure and laboratory parameters are unspecific. No clear-cut definition of neonatal sepsis has been agreed to, although several studies have tried to identify one [5-7]. Clinicians thus permit over-treatment based on the high risk of mortality if sepsis is left untreated. Normally, when the clinician suspects neonatal infection or sepsis, blood culture and cultures of various body sites are immediately undertaken and administration of broad-spectrum antimicrobial agents is empirically started. Although blood cultures are usually the basis for a diagnosis of sepsis due to bloodstream infection, culture results are reported after several days and sensitivity is particularly low for neonates [8,9]. We have encountered many cases in which pathogens have not been detected from culture even thou