• Clinical science

Chorioamnionitis, neonatal infection, and omphalitis

Abstract

Chorioamnionitis is defined as an intrauterine infection of the fetal membranes and amniotic fluid caused by bacteria ascending from the vagina. The most common pathogens are Ureaplasma and Mycoplasma species. Infected women typically present with fever, purulent vaginal discharge, and malodorous amniotic fluid. The combination of maternal (> 120/min) and fetal tachycardia (> 160/min) is highly indicative of intrauterine infection, and the condition should be mananged promptly with antibiotics, supportive care, and possibly early delivery.

Chorioamnionitis, as well as colonization of the maternal genital tract with group B Streptococcus, may also be the cause of dangerous infections in the newborn. These include pneumonia, meningitis, and sepsis, and may be difficult to differentiate because symptoms in neonates are often nonspecific. Common findings include irritability, lethargy, temperature changes, dyspnea, and signs of cardiocirculatory distress (e.g., hypotension). If neonatal infection is suspected, diagnostic procedures should be initiated immediately to identify the pathogen and source of infection (e.g., blood and urine cultures). Management consists mainly of swift initiation of broad-spectrum empiric antibiotic therapy. Without proper treatment, systemic neonatal infections are associated with a high risk of complications and increased mortality rates.

Newborns are also commonly affected by localized infections such as omphalitis, an infection of the umbilical stump. The condition is most often caused by Staphylococcus aureus and group A Streptococcus and occurs 3–9 days after delivery. Clinical features include localized inflammation, swelling, and purulent discharge, which may progress to complications like sepsis and necrotizing fasciitis if not treated adequately with antibiotics (e.g., ampicillin, gentamicin).

Chorioamnionitis

Etiology

Symptoms

Diagnosis

Chorioamnionitis is a clinical diagnosis (fever plus ≥ 1 additional symptom). Tests support or confirm diagnosis if the clinical presentation is ambiguous (e.g., in subclinical chorioamnionitis).

  • Maternal blood tests:
  • Bacterial cultures
    • Urogenital secretions
    • Amniotic fluid (most reliable, but rarely conducted)
  • Group B Streptococcus screening: cervicovaginal and rectal swabs

Management

Complications

References:[1][2][3][4]

Neonatal infection and sepsis

Etiology

Streptococcus agalactiae and Escherichia coli are the most common causes of both early- and late-onset neonatal sepsis!

Symptoms

General presentation

  • Nonspecific
  • Irritability, lethargy, poor feeding
  • Temperature changes (fever and hypothermia both possible)
  • Cardiocirculatory: tachycardia, hypotension, poor perfusion, and delayed capillary refill > 3 sec
  • Respiratory: tachypnea, dyspnea; (e.g., expiratory grunting), apnea (more common in preterm infants)
  • Skin tone: jaundiced and/or bluish-gray (indicates poor perfusion)

Specific symptoms

Diagnosis

Management

  • Supportive care (cardiopulmonary monitoring and support)
  • Broad-spectrum antibiotics: IV ampicillin and gentamicin
    • Indications: clinical suspicion, confirmed or suspected maternal infection (e.g., chorioamnionitis)
  • Adapt therapy according to antibiogram results

Prophylaxis for neonatal GBS infection

Prognosis

References:[5][6][7][8][9][10][11]

Omphalitis

Etiology

Symptoms

  • Periumbilical redness, tenderness, swelling, and hardening
  • Purulent discharge
  • Signs of systemic infection (see “Neonatal infection” above)

Diagnosis

  • Generally a clinical diagnosis, although cultures should be conducted
  • Bacterial cultures: pathogen identification and antibiogram (sample of discharge)
  • In systemic infection: blood and cerebrospinal fluid cultures (detection of sepsis and meningitis)

Management

Complications

Prevention

  • Keep the navel dry (frequent diaper change)
  • Observe general hygiene measures
  • Marking the area of inflammation at diagnosis helps to assess improvement following treatment!

References:[12][13][14]