What is the recommended management for a pregnant woman in her third trimester with streptococcal (strep) pharyngitis?

Management of Strep Throat During Third Trimester of Pregnancy

Penicillin or amoxicillin should be used as first-line treatment for streptococcal pharyngitis in pregnant women in their third trimester, with a 10-day course recommended to effectively eradicate the infection and prevent complications.

Diagnosis of Strep Throat in Pregnancy

When evaluating a pregnant woman with suspected strep throat:

• Look for key clinical features:

  • Fever
  • Tonsillar exudate
  • Tender anterior cervical lymphadenopathy
  • Absence of cough (suggests bacterial rather than viral etiology)

• Diagnostic testing:

  • Rapid antigen detection test (RADT) is recommended
  • If RADT is negative, follow with throat culture (especially important in pregnancy)
  • Testing is crucial before initiating antibiotics to confirm Group A Streptococcus (GAS)

Antibiotic Treatment Recommendations

First-line therapy:

• Penicillin V: 500 mg orally twice daily for 10 days 1, 2
• Amoxicillin: 500 mg orally three times daily for 10 days (alternative first-line) 1, 2

For penicillin-allergic patients (non-anaphylactic):

• Cephalexin: 500 mg orally twice daily for 10 days 1

For penicillin-allergic patients (anaphylactic):

• Azithromycin: 500 mg orally on day 1, then 250 mg daily for 4 days 1, 3
• Clindamycin: 300 mg orally three times daily for 10 days 1

Important: Resistance to macrolides (including azithromycin) has been reported in some regions of the US, so susceptibility testing is recommended when using these alternatives 2.

Supportive Care

• Symptomatic relief:

  • Acetaminophen for fever and pain
  • Adequate hydration
  • Throat lozenges (shown to be safe in pregnancy) 4
  • Warm salt water gargles

• Avoid the following:

  • NSAIDs in late pregnancy (associated with premature closure of ductus arteriosus)
  • Systemic corticosteroids (not recommended for routine treatment) 2, 5
  • Tetracyclines, fluoroquinolones, and trimethoprim-sulfamethoxazole 1

Special Considerations in Third Trimester

1. GBS vs. GAS distinction:

   • Strep throat is typically caused by Group A Streptococcus (GAS)
   • Group B Streptococcus (GBS) screening at 35-37 weeks is part of routine prenatal care but addresses a different issue 6
   • Both require different management approaches

2. Monitoring for complications:

   • Invasive GAS infection in pregnancy, though rare, can be severe with high mortality rates 7
   • Watch for signs of deterioration:
     • Persistent high fever despite antibiotics
     • Strong uterine contractions
     • Signs of shock
     • Flu-like symptoms with rapid progression

3. When to consider hospitalization:

   • Inability to tolerate oral medications
   • Signs of systemic illness or dehydration
   • Evidence of peritonsillar abscess or other complications
   • Concern for invasive GAS disease

Follow-up Recommendations

• Clinical improvement should be seen within 48-72 hours of antibiotic initiation
• If symptoms worsen or persist after 5 days of appropriate treatment, reevaluation is necessary
• Complete the full 10-day course of antibiotics even if symptoms resolve earlier

Important Pitfalls to Avoid

1. Do not confuse GAS (strep throat) with GBS colonization:

   • GBS screening is routine in pregnancy (35-37 weeks) but addresses a different issue
   • GBS requires intrapartum antibiotic prophylaxis during labor, not antepartum treatment 6

2. Do not use antepartum antibiotics for GBS colonization:

   • Antibiotics should not be used before the intrapartum period to eradicate GBS colonization 6

3. Do not use macrolides empirically without susceptibility testing:

   • Significant resistance to azithromycin exists in some regions 2

4. Do not discontinue antibiotics early:

   • Complete the full 10-day course to prevent complications and recurrence

By following these guidelines, strep throat in the third trimester of pregnancy can be effectively managed while minimizing risks to both mother and baby.