What is the recommended treatment for a pregnant patient diagnosed with streptococcal infection, considering the use of 3rd generation levofloxacin (levofloxacin)?

Do Not Use Levofloxacin for Streptococcal Infection in Pregnancy

Levofloxacin (a fluoroquinolone, not a "3rd generation" antibiotic) is contraindicated in pregnancy for streptococcal infections and should be strictly avoided due to potential fetal toxicity. 1

Correct First-Line Treatment for Streptococcal Infections in Pregnancy

For Group A Streptococcal Pharyngitis

• Penicillin V is the treatment of choice: 250 mg orally three to four times daily for 10 days 2
• Amoxicillin 500 mg orally every 8 hours is equally effective and often preferred due to better palatability 2, 3
• Intramuscular benzathine penicillin G (1.2 million units as a single dose) is an excellent alternative that ensures compliance 2

For Group B Streptococcal Infections

If GBS urinary tract infection (any concentration):

• Treat immediately with amoxicillin 500 mg every 8 hours for 7-10 days 4, 5
• The patient will still require intrapartum antibiotic prophylaxis during labor regardless of prenatal treatment 4, 5

If GBS vaginal colonization only:

• Do not treat during pregnancy—this is ineffective and promotes resistance 4, 6
• Reserve treatment for intrapartum prophylaxis during active labor 4, 6

Intrapartum prophylaxis (during labor):

• Penicillin G 5 million units IV initially, then 2.5 million units IV every 4 hours until delivery is the preferred regimen 2, 4
• Ampicillin 2 g IV initially, then 1 g IV every 4 hours is an acceptable alternative 2, 4

Treatment for Penicillin-Allergic Patients

For patients without high-risk allergy symptoms (no history of anaphylaxis, angioedema, respiratory distress, or urticaria):

• Cefazolin 2 g IV initially, then 1 g IV every 8 hours is the preferred alternative 2, 4
• Oral cephalexin 500 mg every 6 hours can be used for outpatient UTI treatment 5

For patients at high risk for anaphylaxis:

• Clindamycin 900 mg IV every 8 hours (or 300-450 mg orally every 6 hours for UTI) if susceptibility testing confirms the isolate is susceptible 2, 4, 5
• Vancomycin 1 g IV every 12 hours if susceptibility testing is unavailable or the isolate is resistant to clindamycin 2, 4
• Susceptibility testing for clindamycin and erythromycin must be performed on GBS isolates from penicillin-allergic patients at high risk for anaphylaxis 2, 4

Why Fluoroquinolones Are Contraindicated

• Quinolones (including levofloxacin) should be strictly avoided during pregnancy due to potential toxicity to the unborn child 1
• Beta-lactam antibiotics (penicillins and cephalosporins) have a long history of safe use in pregnancy and remain the safest choice 3, 7
• Penicillin and ampicillin provide excellent activity against both Group A and Group B streptococci 3

Critical Clinical Pitfalls to Avoid

• Never use fluoroquinolones in pregnancy—they are associated with fetal cartilage and joint toxicity 1
• Do not attempt to "decolonize" GBS vaginal colonization with antibiotics during pregnancy—this is ineffective and promotes antibiotic resistance 4, 6
• Do not forget intrapartum prophylaxis for women with GBS bacteriuria—even if the UTI was treated earlier in pregnancy, they still require prophylaxis during labor 4, 5
• Complete the full antibiotic course—underdosing or premature discontinuation leads to treatment failure and recurrence 4, 5
• Verify penicillin allergy history—many reported penicillin allergies are not true IgE-mediated reactions, and allergy testing can safely restore first-line antibiotic options 4, 8