Neonatal Sepsis

Question 1

Etiology of Neonatal Sepsis

Answer 1

Onset of neonatal sepsis can be
A) Early (≤ 3 days of birth)
B) Late (after 3 days)

• Early-onset neonatal sepsis:-

Early-onset neonatal sepsis usually results from organisms acquired intrapartum. Most infants have symptoms within 6 hours of birth.

1- group B streptococcus (GBS) and
2- Escherichia coli.
3- H influenzae (especially premature neonates)
Others (Klebsiella - Listeria )

• Late-onset neonatal sepsis:-
  Late-onset neonatal sepsis is usually acquired from the environment

1-Staphylococci (particularly central vascular catheters)
2- E coli (especially in extremely LBW infants )
3- Enterobacter sakazakii (from blood or cerebrospinal fluid may be due to contaminated feeding )
4- candida (extremely LBW infants )

!! Early- and late-onset neonatal sepsis
Certain viral infections (eg, disseminated herpes simplex, enterovirus, adenovirus, respiratory syncytial virus) may manifest as early-onset or late-onset sepsis.

Question 2

Pathophysiology of Neonatal Sepsis

Answer 2

A) Early-onset neonatal sepsis:-

1-Premature rupture of membranes (PROM) occurring ≥ 18 hours before birth

2-Maternal chorioamnionitis (most commonly manifesting as maternal fever shortly before or during delivery with maternal leukocytosis, tachycardia, uterine tenderness, and/or foul smelling amniotic fluid)

3- Colonization with GBS
4- Preterm delivery

B) Late-onset neonatal sepsis :-

The most important risk factor in late-onset sepsis is
1- Preterm delivery

Other risk factors include:-
1- Prolonged use of intravascular catheters
2- Exposure to antibiotics
3- Prolonged hospitalization
4- Contaminated equipment or IV or enteral solutions