Pediatrics · Year 3 · from Pediatrics

Case 2: Neonatal Sepsis

Patient Demographics

  • Age: 5-day-old female
  • Sex: Female

Chief Complaint

"She won't eat and feels cold."

History of Present Illness

A 5-day-old female infant is brought to the emergency department because she has been refusing to breastfeed for the past 8 hours. Her mother reports the baby has been less active than usual and feels cool to the touch. The baby was born at 38 weeks gestation via vaginal delivery after spontaneous rupture of membranes 26 hours prior to delivery. The mother was Group B Streptococcus positive and received one dose of penicillin 2 hours before delivery (inadequate prophylaxis). The mother had a temperature of 38.2C during labor. The baby appeared well at birth and was discharged home at 48 hours.

Physical Examination

  • Vital Signs: Temperature 36.0C (rectal - hypothermic), HR 185 bpm, RR 64/min, BP 52/32 mmHg, SpO2 94% on room air
  • General: Lethargic, pale infant with weak cry
  • Skin: Mottled, cool extremities, capillary refill 4 seconds
  • HEENT: Anterior fontanelle flat
  • Cardiovascular: Tachycardic, weak pulses, no murmur
  • Respiratory: Tachypneic, mild subcostal retractions, lungs clear
  • Abdomen: Soft, mildly distended, decreased bowel sounds
  • Neurologic: Decreased tone, minimal response to stimulation

Laboratory Findings

  • CBC: WBC 2,800/uL (low), 45% bands, 30% segmented neutrophils (left shift); Platelets 85,000/uL (low); Hemoglobin 14 g/dL
  • CRP: 8.5 mg/dL (elevated)
  • Blood culture: Pending
  • Urinalysis: Negative
  • CSF: WBC 250 cells/uL (elevated), 85% neutrophils, Protein 180 mg/dL (elevated), Glucose 25 mg/dL (low); Gram stain shows gram-positive cocci in chains
  • Blood gas: pH 7.25, pCO2 32, HCO3 14 (metabolic acidosis)

Diagnosis

Early-onset neonatal sepsis with meningitis (Group B Streptococcus)

Clinical Reasoning

This infant presents with signs of septic shock (hypothermia, tachycardia, poor perfusion, metabolic acidosis) in the setting of multiple risk factors for early-onset sepsis: maternal GBS colonization with inadequate intrapartum antibiotic prophylaxis (only 1 dose, <4 hours before delivery) and prolonged rupture of membranes (26 hours). The CSF findings (elevated WBC with neutrophil predominance, elevated protein, low glucose, gram-positive cocci) confirm bacterial meningitis. Group B Streptococcus is the most common cause of early-onset sepsis and neonatal meningitis. Neutropenia and thrombocytopenia are poor prognostic signs indicating bone marrow suppression.

Management

  1. IV antibiotics: Start IMMEDIATELY after obtaining cultures
  • Ampicillin 300-400 mg/kg/day divided every 6 hours (meningitis dosing)
  • Gentamicin 4-5 mg/kg/dose every 24-36 hours based on gestational age
  1. Fluid resuscitation: 20 mL/kg normal saline bolus, repeat as needed
  2. Respiratory support: Supplemental oxygen; prepare for intubation if respiratory failure develops
  3. Glucose: Monitor closely; treat hypoglycemia with D10W
  4. Correct acidosis: Usually improves with resuscitation
  5. Vasopressors: Dopamine or epinephrine if hypotension persists after fluid resuscitation
  6. Duration of antibiotics: Minimum 14-21 days for GBS meningitis
  7. Repeat lumbar puncture: At 24-48 hours to document CSF sterilization
  8. Hearing screening: Before discharge (meningitis is a risk factor for hearing loss)

Clinical Image

Image Description: Cerebrospinal fluid specimen from a neonate with bacterial meningitis, appearing turbid (cloudy) due to elevated white blood cell count, compared with normal clear CSF.

Source: Wikimedia Commons URL: https://commons.wikimedia.org/wiki/File:CSF_bacterial_meningitis.jpg License: CC BY-SA 3.0

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