What are the risks and recommended treatment for a pregnant woman who has suffered a cat scratch to the face, potentially exposing her to cat-scratch disease caused by Bartonella henselae?

Cat Scratch to Face of Pregnant Woman

For a pregnant woman with a cat scratch to the face, immediately wash the wound thoroughly with soap and water, then monitor for development of regional lymphadenopathy over the next 3 weeks; if cat scratch disease develops, treat with azithromycin 500 mg on day 1 followed by 250 mg daily for 4 additional days, as this is the only safe and effective antibiotic regimen specifically validated for pregnant women with Bartonella henselae infection. 1

Immediate Wound Management

• Promptly wash any cat-associated wound with soap and water immediately after the scratch occurs 2
• This simple intervention is the most important initial step to reduce bacterial inoculation and prevent infection 2

Clinical Monitoring Timeline

• A papule or pustule may develop 3-30 days after the scratch if infection occurs 1
• Regional lymphadenopathy (in this case, preauricular, submandibular, or cervical nodes) typically appears approximately 3 weeks after inoculation 1
• Most lymphadenopathy resolves spontaneously within 1-6 months, with suppuration occurring in about 10% of cases 1

Risk Assessment for Pregnancy

Pregnant women face unique considerations with Bartonella infection, though the evidence base is limited to HIV-infected pregnant women in the available guidelines. The guidelines specifically address antibiotic selection during pregnancy but do not suggest pregnancy itself increases disease severity 2.

Key pregnancy-specific concerns:

• Tetracyclines (doxycycline) are absolutely contraindicated during pregnancy 2, 1
• Fluoroquinolones should not be used during pregnancy 2
• Erythromycin is safe for use during pregnancy 2, 1
• Azithromycin (a macrolide in the same class as erythromycin) is the preferred first-line agent 1

Treatment Algorithm

For Immunocompetent Pregnant Women:

If lymphadenopathy develops:

• First-line: Azithromycin 500 mg on day 1, then 250 mg daily for 4 additional days 1
• This regimen is based on the only placebo-controlled study showing more rapid reduction in lymph node size 1, 3
• Alternative: Erythromycin 500 mg four times daily if azithromycin is unavailable 1

If no lymphadenopathy develops within 3-4 weeks:

• No treatment is necessary, as most immunocompetent individuals do not require antibiotics for resolution 3, 4, 5

For Severe or Disseminated Disease (rare in immunocompetent patients):

• Extranodal disease develops in ≤2% of cases and may include hepatosplenic involvement, encephalopathy, osteomyelitis, or endocarditis 1, 3, 5
• For severe cases with hepatosplenic involvement: Consider gentamicin, which has shown 73% efficacy with rapid response within 48 hours 1
• For CNS involvement: Erythromycin is the only safe option during pregnancy (doxycycline with or without rifampin would normally be preferred but is contraindicated) 1

Prevention Counseling for Future

Provide the following guidance to prevent future exposures:

• Avoid rough play with cats and situations where scratches are likely 2, 1
• Do not allow cats to lick open wounds or cuts 2, 1
• Implement comprehensive flea control for household cats, as cat fleas are the vector of B. henselae among cats 2, 1, 4
• If acquiring a new cat, choose one >1 year old in good health (younger cats have higher infection rates) 2, 1

Common Pitfalls to Avoid

Do not order serologic testing immediately - antibodies may not be detectable until 6 weeks after acute infection, leading to false-negative results if tested too early 1

Do not test the cat for Bartonella infection - this provides no benefit to diagnosis or management and is not recommended 2, 1

Do not use penicillins or first-generation cephalosporins - these have no in vivo activity against Bartonella 1

Do not delay treatment if severe symptoms develop - while most cases are self-limited, pregnant women should receive treatment if systemic symptoms or significant lymphadenopathy develops, given the theoretical (though undocumented) risk of dissemination 1

When to Escalate Care

• Temperature ≥38.5°C or pulse ≥100 bpm suggests more invasive infection requiring closer monitoring 6
• Visual changes, severe headache, altered mental status, or signs of systemic toxicity require immediate evaluation for extranodal disease 1, 5
• Persistent fever without localizing signs in the context of recent cat exposure should prompt consideration of Bartonella bacteremia 2, 1