Part K: Infectious Disease

Early-Onset Sepsis

EVALUATION

Septic neonates can have dramatic clinical presentations characterized by respiratory failure, persistent pulmonary hypertension of the newborn (PPHN), disseminated intravascular coagulation (DIC), hypotension, or multiorgan failure. More challenging for health care providers, however, are more commonly encountered patients with subtle and nonspecific signs and symptoms or risk factors for sepsis. Considering the deleterious consequences of a missed or delayed diagnosis, a high index of suspicion is warranted when undertaking evaluation of neonates for potential sepsis.

Maternal History

Careful history is essential for determining key risk factors associated with early-onset sepsis (EOS). Clinicians should confirm the following:

1. Maternal group B streptococci (GBS) status.

2. Use of GBS-specific intrapartum antibiotic prophylaxis vs broad-spectrum intrapartum antibiotic use.

3. Duration of time between rupture of membranes and birth.

4. Length of time of intrapartum antibiotic administration (>4 hours).

5. Intrapartum maternal fever.

6. Gestational age of the newborn.

Labor and Delivery

The clinical presentation of a septic infant can start as early as labor and delivery. Signs and symptoms may include the following:

1. Intrapartum fetal tachycardia.

2. Meconium staining of amniotic fluid.¹

3. Low Apgar scores (newborns with an Apgar score ≤ 6 at 5 minutes had a 36-fold higher likelihood of sepsis than those with Apgar scores ≥ 7).²

Clinical Signs and Physical Findings

After birth, clinical signs of sepsis present in a range from nonspecific and subtle to severe multisystem dysfunction. More commonly presenting signs include the following:

1. Neurological: Temperature instability (fever or hypothermia, with fever more common in term newborns and hypothermia more likely in preterm neonates³); apnea; lethargy or irritability; hypotonia; weak cry; poor suck; seizures.

2. Respiratory: Tachypnea; respiratory distress (flaring, grunting, retractions, or decreased breath sounds); and pulmonary hemorrhage.

3. Cardiovascular: Tachycardia or bradycardia; cyanosis; hypotension; prolonged capillary refill time; mottled appearance; cool and clammy skin.

4. Hematological: Jaundice, petechiae, purpura, and pallor.

5. Gastrointestinal: Abdominal distension, feeding intolerance, emesis, diarrhea, bloody stools, and hepatomegaly.

6. Renal: Oliguria, anuria.

Diagnostic Tests/Laboratory Testing

Several tests are almost universally obtained for the evaluation of EOS; others are still limited by the lack of evidence to support widespread use:

1. Blood culture: This remains the gold standard for diagnosis of EOS. Although there is a considerably high incidence of false-negative cultures^4,5 obtained from neonates, a culture absent of bacterial growth at 36–48 hours from a newborn with no other signs of EOS is reassuring. One small prospective cohort study has also examined utilizing cord blood for blood culture sampling in asymptomatic term newborns evaluated for sepsis based on the presence of risk factors.⁶ The authors concluded it may be a reasonable consideration, but additional studies are needed before a practice recommendation can be made. For those neonates who fail to demonstrate improvement ...