The impaired infection control related to the functional immaturity of the neonatal immune system is an important cause of infection in preterm newborns. We previously reported that constitutive Toll-like receptor (TLR) 4 expression and cytokine secretion on lipopolysaccharide (LPS) stimulation increases with gestational age. Here, we analyzed constitutive monocyte TLR2 expression and evaluated the expression profiles of the proximal downstream adapter molecule myeloid differentiation factor 88 (MyD88). We further investigated activation of protein kinases p38 and extracellular regulated kinsase (ERK) 1/2 in CD14 monocytes after ex vivo stimulation with bacterial TLR ligands (LPS and lipoteichoic acid [LTA]). The functional outcome of the stimulation was determined by cytokine secretion. Monocytes from 31 preterm newborns (<30 weeks of gestation, n=16; 30-37 weeks of gestation, n=15), 10 term newborns, and 12 adults were investigated. In contrast to TLR4 expression, TLR2 levels did not differ between age groups. However, MyD88 levels were significantly lower in preterm newborns. Activation of p38 and ERK1/2 was impaired in all newborn age groups after stimulation with TLR-specific ligands. Accordingly, after LTA stimulation, the levels of interleukin (IL)-1 beta , IL-6, and IL-8 cytokine production were substantially lower (P<.001) in preterm newborns than in adults. The reduced functional response to bacterial cell wall components appears to be part of the functional immaturity of the neonatal immune system and might predispose premature newborns to bacterial infection.

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Isolation of pathogens from the amniotic cavity at birth is significantly associated with abnormal PDI and adverse neuromotor outcome in preterm infants, irrespective of gestational age and birthweight.

Our data provide evidence of a potential effect of simulation-based training of central line placement in decreasing CLABSI rates in VLBWI and encourage its implementation into care bundles.

Background: Conventional blood culture is still the gold standard for sepsis diagnosis but results are not immediately available and pathogens are only detected in approximately 25% of cases. New molecular assays for the detection of blood stream pathogens are promising diagnostic tools. Objectives: The aim of the study was to adapt and evaluate a multiplex PCR system using 100 µl blood. -Methods: 46 blood specimens of very low birth weight infants (818 ± 242 g) with suspected sepsis were analyzed using the Roche SeptiFast MGRADE PCR with a modified DNA extraction protocol and software handling tool for decreased blood volume requirements. Results: In the non-infected group, 5/21 infants had a positive PCR result with coagulase-negative staphylococci. All pathogens detected in the blood culture positive group (n = 15) were also detected by PCR. In addition, 4/6 patients had a positive PCR result in the clinical sepsis group (clinical and laboratory signs of sepsis but negative blood culture). Overall, the PCR was demonstrated to have a higher sensitivity (90.5%; 95%CI 68.2-98.3%) in comparison to blood culture (71.4%; 95%CI 47.7-87.8%) including clinical sepsis cases, even though it had a lower specificity (80.0%; 95%CI 58.7-92.4% versus 100.0%; 95%CI 83.4-100.0%). Conclusions: These first data demonstrate the usability and potential benefit of this multiplex PCR using a modified DNA extraction for the rapid detection of nosocomial sepsis in preterm infants in addition to blood culture.

Intravenous sildenafil treatment seems effective in improving severe PH and hemodynamic instability in extremely preterm infants with refractory PH. Pulmonary hemorrhage may represent a distinct adverse effect of sildenafil treatment in these patients, presumably due to sudden reversal of ductal shunt. Accordingly, sildenafil should be restricted to most severe and refractory cases in this population.

To test the hypothesis that a considerable number of preterm infants acquire respiratory syncytial virus (RSV) within the hospital during the postnatal stay, a prospective epidemiologic survey was performed. Nasopharyngeal swabs were taken twice weekly for a period of 8 weeks from preterm infants, medical/nursing staff, and parents during the peak of RSV season 2007/2008 and tested for RSV by polymerase chain reaction. Of 1002 samples, only 4 tested positive (2 from a patient, 2 from staff). Sequence analyses of the G protein demonstrated that nosocomial transmission did not occur between these individuals.

Patients <26 weeks of gestational age requiring PDA ligation showed significant differences in the course of vital signs and pH during the first days of life.