What are the risks and treatment options for Group A streptococcal (GAS) infection during pregnancy?

Group A Streptococcal Infection in Pregnancy: Risks and Management

Group A streptococcal (GAS) infection during pregnancy and the postpartum period carries significant mortality risk, with maternal deaths from GAS genital tract sepsis increasing from 1 per year (2000-02) to 4 per year (2006-08) in the UK, and GAS remains the most common infectious cause of severe maternal morbidity and death worldwide. 1, 2

Epidemiology and Risk Factors

Incidence and Timing:

• Pregnancy-related GAS infections occur at a rate of approximately 0.06-0.8 per 1000 live births 1, 3
• Between 2-11% of all severe GAS infections are associated with recent childbirth 1
• 93% of pregnancy-related GAS infections occur in the puerperium (postpartum period) 3
• Case fatality rates for severe GAS infection range from 8-23% in developed countries 1

Protective Factors:

• Cesarean delivery appears protective (adjusted OR 0.44), likely due to routine perioperative antibiotic prophylaxis 3
• Primiparity is protective (adjusted OR 0.60), possibly due to less exposure to children who carry GAS 3

High-Risk Scenarios:

• Women with recent respiratory tract infections or family members with recent sore throats are at increased risk 1
• Vaginal delivery with use of communal bathing facilities (baths, bidets, showers) significantly increases risk 1

Clinical Presentation

Key Warning Signs:

• Fever (>100.4°F/38.0°C on more than two occasions >6 hours apart after first 24 hours postpartum) 4
• Hypogastric pain and uterine tenderness 4
• Foul-smelling lochia 4
• Symptoms often lack specificity, making early recognition challenging 3, 5

Severe Manifestations:

• 23% of pregnancy-related GAS infections are severe, including necrotizing fasciitis and toxic shock syndrome 3, 5
• Invasive GAS causes 40% of septic deaths among patients with postpartum endometritis 5

Treatment Approach

Immediate Antibiotic Therapy:

• Initiate broad-spectrum antibiotics with anaerobic coverage immediately upon suspicion of postpartum endometritis 4
• All patients should receive β-lactam antibiotics (penicillin or ampicillin as first-line) 2, 3
• Add clindamycin in 84% of cases for enhanced toxin suppression and improved outcomes 3
• Obtain blood and endocervical cultures before starting antibiotics when possible 4

Supportive Care:

• Provide adequate hydration and assess for dehydration (orthostatic hypotension, decreased skin turgor, dry mucous membranes) 4
• Use acetaminophen as first-line for pain control 4

Surgical Intervention:

• Only 3% of cases require surgical intervention; most recover with conservative medical treatment 3
• However, maintain high suspicion for necrotizing fasciitis, which requires urgent surgical debridement 5

Infection Control Measures

Patient Isolation:

• Isolate the patient in a single room with self-contained toilet and hand basin 4
• Continue isolation for at least 24 hours after initiating effective antibiotic therapy 4
• Handle linen and waste as hazardous while patient is considered infectious 1

Environmental Decontamination:

• Clean and decontaminate communal facilities (baths, bidets, showers) between ALL patients on delivery suites and post-natal wards 1
• Use detergent and water followed by hypochlorite at 1000 ppm for environmental cleaning 1
• Environmental sources account for 9.8% of hospital GAS outbreaks, with bathrooms particularly implicated in maternity settings 1

Mother-Baby Dyad Management

Keeping Mother and Baby Together:

• Do not separate mother and baby unless either requires ICU admission 1, 4
• Babies born to infected mothers may become colonized; swab umbilicus, ears, and nose 1

Treatment of Both:

• Administer antibiotics to both mother and baby if either develops suspected or confirmed invasive GAS disease in the neonatal period (first 28 days) 1
• Maternal and neonatal infections are closely related in timing 1
• Support breastfeeding, as most antibiotics used are compatible 4

Contact Management

Close Personal Contacts:

• Do NOT routinely administer antibiotics to contacts of GAS cases 1
• Provide written information to close contacts (household members, kissing contacts within 7 days prior to illness onset) 1
• Contacts should seek urgent medical attention if they develop signs/symptoms of invasive GAS within 30 days 1
• Notify local health protection specialist of all invasive GAS infections 1

Healthcare Worker Screening

When to Screen:

• Screen healthcare workers epidemiologically linked to cases when no alternative source is identified 1
• Less than 5% of adults carry GAS in their throat, so positive results should be acted upon 1

Screening Sites:

• Initial screening: throat and skin lesions (including all exfoliating conditions) 1
• If initial sites negative: nose, anus, and vagina 1
• Throat colonization is the most common source in healthcare workers 1

Critical Pitfalls to Avoid

• Do not dismiss nonspecific symptoms in postpartum women—fever and abdominal tenderness may be the only early signs 3, 5
• Do not assume hospital-acquired infection only—community acquisition is common, with many cases linked to family members with sore throats 1, 3, 6
• Do not delay antibiotics while awaiting culture results in suspected cases 4
• Do not overlook environmental sources, particularly shared bathing facilities on maternity units 1
• Do not separate mother and baby unnecessarily, as this disrupts bonding and breastfeeding without clear benefit 1, 4