What is the recommended treatment for Q (Query) fever in pregnancy?

Treatment of Q Fever in Pregnancy

Pregnant women with Q fever should be treated with trimethoprim/sulfamethoxazole (160 mg/800 mg twice daily) throughout pregnancy to prevent adverse outcomes including miscarriage, premature delivery, and development of chronic Q fever. 1

Understanding Q Fever in Pregnancy

Q fever, caused by the bacterium Coxiella burnetii, presents unique challenges during pregnancy. The infection carries significant risks:

• Higher risk of adverse outcomes when infection occurs in the first trimester
• Potential for miscarriage, premature delivery, intrauterine growth restriction
• Risk of maternal progression to chronic Q fever
• Possibility of recrudescent infection in subsequent pregnancies

Treatment Algorithm

1. Confirm diagnosis:

   • Evaluate serologic results (phase II antibody response is elevated in acute infection)
   • Consider epidemiological factors (contact with infected livestock, occupational exposure)

2. Initiate treatment immediately upon diagnosis:

   • First-line therapy: Trimethoprim/sulfamethoxazole 160 mg/800 mg twice daily throughout pregnancy 1
   • Alternative (in case of intolerance): Clarithromycin (as reported in case studies) 2

3. Duration of treatment:

   • Continue treatment throughout the entire pregnancy 1, 3
   • Do not discontinue early even if symptoms resolve

4. Post-delivery management:

   • Monitor for development of chronic Q fever
   • For women with serologic profile indicating chronic Q fever: doxycycline 100 mg twice daily plus hydroxychloroquine 200 mg three times daily for 12 months 1

Efficacy of Treatment

Long-term trimethoprim/sulfamethoxazole therapy has been shown to:

• Protect against abortion, particularly when infection occurs in first trimester 4, 3
• Reduce the risk of placental infection 3
• Prevent maternal progression to chronic Q fever 3
• Decrease overall obstetric complications 3

Important Considerations and Precautions

• Timing matters: First trimester infections carry the highest risk for miscarriage and maternal chronic Q fever 1
• Folic acid supplementation: Recommended during trimethoprim/sulfamethoxazole treatment due to antifolate effects 1
• Monitoring: Regular serologic monitoring during pregnancy and for 24 months after delivery 1
• Future pregnancies: Women with history of Q fever during pregnancy should be monitored closely in subsequent pregnancies for recrudescent infection 1
• Contraception advice: Women diagnosed with acute Q fever should avoid pregnancy for at least 1 month after diagnosis and treatment 1

Special Situations

• Chronic Q fever endocarditis in pregnancy: Requires consultation with infectious disease specialists 1
• Drug intolerance: If trimethoprim/sulfamethoxazole cannot be tolerated, clarithromycin has been used successfully in case reports 2

While doxycycline is the standard treatment for Q fever in non-pregnant adults 5, it is contraindicated during pregnancy due to potential effects on fetal bone development and dentition 1.