Rita P Verma

Nassau University Medical Center, USA

Abstract

Objective:

The immediate postnatal rectal (RC) and nasopharyngeal colonization (NPC), and their prevalence, taxa and associated characteristics were investigated in sick term infants admitted to the NICU.

Study design:

In a retrospective cohort single center study, nasopharyngeal (NPCx) and rectal (RCx) microbial cultures were obtained within 20 minutes of birth in mild to moderately sick term infants. Associations between the colonization, and maternal-neonatal variables, including early neonatal course were analyzed via logistic regression analysis.

Results:

A total of154 term infants were admitted for respiratory distress, hypoglycemia, maternal chorioamnionitis (CHO) and suspected neonatal sepsis, out of which 80(52%) were NPCx-positive. The duration of rupture of membrane (ROM) was higher (15.5+10.0 vs. 11.3 +11.0 hours, p=0.02) while the respiratory support requirement (16.3% vs. 29.7%, p =0.04) and occurrence of maternal GBS colonization lower (15.0% vs. 35.1%, p=0.01) in NPCx-positive infants. ROM increased (OR1.04, 95% CI 1.01-1.07), and maternal GBS colonization decreased the odds of positive NP cultures (OR 0.31, 95% CI 0.14-0.72). The major microorganisms isolated were Staphylococcus epidermidis (SE, 41%), alpha hemolytic Streptococcus (16%), Escherichia coli (E. coli, 13%), and group b Streptococcus ( 1.06%). Among the enrolled infants, 44 (28.5%) were RCx-positive. The need for (11.4% vs.27.3%, p=0.03) and days on respiratory support (0.2+0.6 vs. 0.8+2.5, p=0.03) were lower and the occurrence of CHO higher (41.0% vs. 23.2%, p=0.04) in the RCx-positive infants. Cesarean section (CS) was performed less frequently (18.2% vs. 55.5%, p=0.001) and decreased the odds of having positive rectal cultures (OR 0.21, 95% CI 0.08-0.51). Eighty percent of the RCx-positive infants isolated E coli, and 6.8% Klebsiella.

Conclusion:

In sick term neonates early NPC is dominated by SE, and RC by E. coli. NPC is supported by ROM and declines by maternal GBS colonization, whereas RC decreases with CS.  NPC is more common than RC in this population.