Israel Medical Association Journal

Background: Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a challenging nosocomial pathogen in the last 50 years.

Objectives: To describe an investigation and containment of an MRSA outbreak in a neonatal intensive care unit (NICU).

Methods: Our NICU is a 25-bed level III unit. Almost 540 neonates are admitted yearly. The index case was an 8 day old term baby. MRSA was isolated from his conjunctiva. Immediate infection control measures were instituted, including separation of MRSA+ carriers, strict isolation, separate nursing teams, and screening of all infants for MRSA. Healthcare workers and parents of positive cases were screened and re-educated in infection control measures. New admissions were accepted to a clean room and visiting was restricted. MRSA isolates were collected for molecular testing.

Results: MRSA was isolated from five infants by nasal and rectal swabs, including the index case. Screening of healthcare workers and families was negative. Two MRSA+ patients already known in the pediatric intensive care unit (PICU) located near the NICU were suspected of being the source. All NICU isolates were identical by pulsed-field gel electrophoresis but were different from the two PICU isolates. The NICU and one of the PICU isolates were defined as ST-5 strain by multilocus sequence typing. One PICU isolate was ST-627. All NICU isolates were Panton–Valentine leukocidin negative and SCCmec type IV. No further cases were detected, and no active infections occurred.

Conclusions: A strict infection control policy and active screening are essential in aborting outbreaks of MRSA in the NICU.

Background: Due to a shortage of individualized erythromycin ointment (IEO), we switched to shared erythromycin drops (SED). Following this change, nurses claimed observing more cases of eye discharge. 

Objectives: To test whether switching from IEO to SED affected the rate of neonatal conjunctivitis (NC).

Methods: The study group included 14,916 neonates > 35 weeks of gestation, further divided into two birth periods of 12 months each: 1 January 2013 to 31 December 2013 (IEO) and 1 February 2014 to 31 January 2015 (SED). We compared the two birth periods with regard to three variables: clinical NC (number of conjunctival swabs/1000 neonates), bacterial NC (number of culture-positive swabs/1000 neonates), and bacterial growth percentage (number of culture-positive swabs/100 samples).  

Results: Compared to 2012–2013, the period 2014–2015 included fewer cesarean deliveries and shorter length of stay (LOS). Clinical NC, bacterial NC and bacterial-growth percentage were not different between the two periods. Variables that were independently significantly associated with increased clinical NC included male gender (OR 1.48, CI 1.21–1.81) and LOS (OR 1.24, CI 1.18–1.29). LOS was associated with bacterial NC (OR 1.19, CI 1.11–1.28). Coagulase-negative staphylococci, Escherichia coli and Pseudomonas aeruginosa were the prevalent pathogens, though without difference between periods. 

Conclusions: Rates of clinical NC, bacterial NC and bacterial-growth percentage were not different between the study periods. Switching from IEO to SED had no effect on the NC rate.

 

Background: According to the U.S. Centers for Disease Control guidelines, prolonged rupture of membranes mandates intrapartum antimicrobial prophylaxis for group B Streptococcus whenever maternal GBS[1] status is unknown.

Objectives: To evaluate the local incidence, early detection and outcome of early-onset GBS sepsis in 35–42 week old neonates born after PROM[2] to women with unknown GBS status who were not given intrapartum antimicrobial prophylaxis.

Methods: During a 1 year period, we studied all neonates born beyond 35 weeks gestation with maternal PROM ≥ 18 hours, unknown maternal GBS status and without prior administration of IAP[3]. Complete blood count, C-reactive protein, blood culture and polymerase chain reaction amplification of bacterial 16S rRNA gene were performed in blood samples collected immediately after birth. Unfavorable outcome was defined by one or more of the following: GBS bacteremia, clinical signs of sepsis, or positive PCR[4].

Results:  Of the 3616 liveborns 212 (5.9%) met the inclusion criteria. Only 12 (5.7%) of these neonates presented signs suggestive of sepsis. PCR was negative in all cases. Fifty-eight neonates (27.4%) had CRP[5] > 1.0 mg/dl and/or complete blood count abnormalities, but these were not significantly associated with unfavorable outcome. Early-onset GBS sepsis occurred in one neonate in this high risk group (1/212 = 0.47%, 95% CI 0.012–2.6). 

Conclusions: In this single-institution study, the incidence of early-onset GBS sepsis in neonates born after PROM of ≥ 18 hours, unknown maternal GBS status and no intrapartum antimicrobial prophylaxis was 0.47%.

Background: Factors influencing the oral flora of premature infants have not been adequately investigated.

Objective: To investigate the effects of gestational age and of anti-bacterial therapy on the oral flora of premature infants.

Methods: Oral cultures were obtained at age 1 day and age 10 days from 65 premature infants, divided into three groups: a) 24 neonates of 30-34 weeks gestation who did not receive ABT, b) 23 neonates of 30-34 weeks gestation who received ABT, and c) 18 neonates < 30 weeks gestation who received ABT.

Results: Oral bacterial colonization increased from day 1 to day 10 of life. In 24-34 week neonates, gestational age did not affect early bacteremia or oral colonization at birth. Neither gestational age nor ABT affected late bacteremia or oral colonization at day 10. In 30-34 week neonates with ABT, the oral flora consisted mainly of non-Escherichia coli gram-negative bacteria, whereas those who did not receive ABT grew mainly alpha-hemolytic streptococci, Klebsiella pneumoniae and E. coli in neonates < 30 weeks who received ABT the oral flora were mainly coagulase-negative staphylococci. Oral colonization with anearobes was zero and colonization with fungi was minimal.

Conclusions: Acquistion of oral bacteria rose from day 1 to day 10 of life, regardless of gestational life or ABT. On day 10 of life, the spectrum of oral bacterial flora changed following ABT and consisted mainly of coagulase-negative Staphylococcus and non E. coli garm-negative bacteria. Oral colonization showed few fungi but no anaerobes. These microbiologic observations merit attention when empirical anti-microbial therapy is considered in premature infants suspected or having late-onset sepsis.