Impact of Whole Genome Sequencing to investigate transmission of Serratia marcescens in Neonatal Intensive Care Unit.

Newborns admitted to neonatal intensive care units (NICU) are at increased risk of health care-associated infections. Serratia marcescens represent the third most common pathogen in NICU outbreaks. Here we present an outbreak investigation performed using Whole Genome Sequencing (WGS) analyses and the control measures implemented to limit the spread of S. marcescens in the NICU of an Italian hospital. In February 2023 S. marcescens was isolated from six newborns, when in 2022 this pathogen was isolated only from two samples in the same ward. Measures for infection prevention were adopted. Routinary surveillance screening, performed with rectal swabs collected at admission and weekly thereafter, was implemented to search for S. marcescens presence. Environmental samples were collected. All the isolates, obtained from the conjunctival swab of six newborns, from rectal swab of two newborns who did not develop infections, as well as from the aerators of two faucets, were sequenced. WGS analyses showed no correlation between the isolates from newborns and environmental isolates. The implementation of the measures for infection prevention and control had enabled us to successfully control the outbreak within a short period. WGS analyses proved to be crucial in outbreak investigation to limit the spreading of the pathogens.

Fulminant echovirus 11 hepatitis in male non-identical twins in northern Italy, April 2023.

Echovirus 11 (E11) has recently been associated with a series of nine neonatal cases of severe hepatitis in France. Here, we present severe hepatitis caused by E11 in a pair of twins. In one of the neonates, the clinical picture evolved to fulminant hepatitis. The E11 genome showed 99% nucleotide identity with E11 strains reported in the cases in France. Rapid genome characterisation using next generation sequencing is essential to identify new and more pathogenetic variants.

Neonatal-Onset Familial Mediterranean Fever in an Infant with Human Parainfluenza Virus-4 Infection.

Unusual, severe infections or inflammatory episodes in newborns and infants are largely unexplained and often attributed to immature immune responses. Inborn errors of immunity (IEI) are increasingly recognized as the etiology of life-threatening inflammatory and infectious diseases in infancy. We describe a patient with a unique neonatal-onset Familial Mediterranean Fever (FMF) due to compound heterozygous variants in MEFV, presenting as pleuritis following human parainfluenza virus-4 infection. Diagnostic challenges of FMF in infancy include the interpretation of the attacks as infectious episodes. Newborns and infants with acute, recurrent, or chronic, unusually severe infectious or inflammatory conditions should be screened for IEI, including both disorders with defective immunological responses and autoinflammatory disorders.

Diagnostic performance of triggering receptor expressed on myeloid cells-1 and CD64 index as markers of sepsis in preterm newborns.

OBJECTIVE: CD64 index and triggering receptor expressed on myeloid cells-1 are biomarkers on neutrophil polymorphonuclear cells with crucial role in sepsis. The study aim is to assess diagnostic performance, individually and combined, of CD64 index and triggering receptor expressed on myeloid cells-1 (surface marker/soluble form), in late-onset sepsis of preterm infants. DESIGN: Observational study. SETTING: Neonatal ICU. PATIENTS: Sixteen septic and 16 control preterm infants, gestational age younger than 32 weeks and/or birth weigh less than 1500 g. MEASUREMENT AND MAIN RESULTS: Seventy preterm infants, free of sepsis were enrolled into the study. CD64 index and triggering receptor expressed on myeloid cells-1 were measured once between day 5 and 15 of life (T0) and once between day 16 and 25 (T1). At T1, 16 infants were assigned to septic group because of reported signs of sepsis and positive blood culture. From the remaining 54 infants, 16 of them who always remained free of sepsis had a blood sample at T1 and constituted the control group (n = 16). Comparing T1 vs T0, triggering receptor expressed on myeloid cells-1 polymorphonuclear cells percentage was significantly lower (p = 0.002) in septic group but not in control group; soluble triggering receptor expressed on myeloid cells-1 concentration did not show significant differences in both groups; CD64 index significantly increased (p = 0.0004) in septic group, while no difference was found in control group. Comparing septic with control group at T0, no differences were found in any markers. At T1, triggering receptor expressed on myeloid cells-1 polymorphonuclear cells percentage was significantly lower (p = 0.003) and CD64 index was higher (p = 0.00019) in septic infants. Triggering receptor expressed on myeloid cells-1 polymorphonuclear cells receiver operating characteristic curve indicated cutoff 62.12%, sensitivity 56.2%, specificity 93.5%, and area under the curve 0.8. CD64 index receiver operating characteristic curve indicated cutoff 2.85, sensitivity 87.5%, specificity 100%, and area under the curve 0.95. Combination of the two indexes was not useful in increasing individual diagnostic power. CONCLUSIONS: Despite limited sample size, CD64 index demonstrated to be a promising biomarker, with high specificity, to diagnose late-onset sepsis. Further investigations are needed to substantiate these findings. Triggering receptor expressed on myeloid cells-1 showed less valuable diagnostic role.

Short-term and long-term sequelae in intrauterine growth retardation (IUGR).

Intrauterine Growth Retardation (IUGR) is defined as a rate of growth of a fetus that is less than normal for the growth potential of the fetus (for that particular gestational age). Small for Gestational Age (SGA) is defined infant born following IUGR, with a weight at birth below the 10th percentile.Suboptimal fetal growth occurring in IUGR fetuses is an important cause of perinatal mortality and morbidity. The acute neonatal consequences of IUGR include metabolic and hematological disturbances, and disrupted thermoregulation; in addition, respiratory distress (RDS), necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP) may contribute to perinatal morbidity. Metabolic disturbances are related to glucose and fatty acid metabolism. It is well-known that individuals who display poor growth in utero are at significantly increased risk for type 2 diabetes mellitus (T2DM), obesity, hypertension, dyslipidemia, and insulin resistance (the so-called metabolic syndrome, MS). MS ultimately leads to the premature development of cardiovascular diseases. In addition, short stature in children and adults, premature adrenarche, and the polycystic ovarian syndrome (PCOS) are endocrinological sequelae of IUGR. (8) Early onset growth delay and prematurity significantly increase the risk for neurological sequelae and motor and cognitive delay.Future prospective studies need to investigate risk factors for infants who are SGA. If reliable prediction can be achieved, there is potential to reduce future perinatal morbidity and mortality, and long term consequences among SGA babies.