Clinical signs to identify late-onset sepsis in preterm infants

Late-onset neonatal sepsis (LOS) in preterm infants is an important cause of morbidity and mortality in preterm infants. Since presenting symptoms may be non-specific and subtle, early and correct diagnosis is challenging. We aimed to develop a nomogram based on clinical signs, to assess the likelihood of LOS in preterms with suspected infection without the use of laboratory investigations. We performed a prospective cohort study in 142 preterm infants < 34 weeks admitted to the neonatal intensive care unit with suspected infection. During 187 episodes, 21 clinical signs were assessed. LOS was defined as blood culture-proven and/or clinical sepsis, occurring after 3 days of age. Logistic regression was used to develop a nomogram to estimate the probability of LOS being present in individual patients. LOS was found in 48 % of 187 suspected episodes. Clinical signs associated with LOS were: increased respiratory support (odds ratio (OR) 3.6; 95 % confidence interval (CI) 1.9-7.1), capillary refill (OR 2.2; 95 %CI 1.1-4.5), grey skin (OR 2.7; 95 %CI 1.4-5.5) and central venous catheter (OR 4.6; 95 %CI 2.2-10.0) (area under the curve of the receiver operating characteristic curve 0.828; 95 %CI 0.764-0.892). Conclusion: Increased respiratory support, capillary refill, grey skin and central venous catheter are the most important clinical signs suggestive of LOS in preterms. Clinical signs that are too non-specific to be useful in excluding or diagnosing LOS were temperature instability, apnoea, tachycardia, dyspnoea, hyper- and hypothermia, feeding difficulties and irritability.