What treatment options are considered for a 23-year-old male with recurrent URI-like symptoms, fatigue, and a history of tick bite in Connecticut, with EBV labs showing low IgM and elevated IgG and nuclear antibodies?

Treatment for Recurrent URI-like Symptoms with History of Tick Bite in Connecticut

Doxycycline is the treatment of choice for this patient with suspected tick-borne illness based on his clinical presentation, history of tick bite, and laboratory findings. 1

Clinical Assessment

This 23-year-old male presents with several concerning features:

• Recurrent URI-like symptoms and fatigue over 6 months
• History of tick bite in Connecticut (an endemic area for tick-borne diseases)
• EBV serologic pattern showing past infection (low IgM, elevated IgG and nuclear antibodies)

These findings strongly suggest a tick-borne rickettsial disease (TBRD), particularly Human Granulocytic Anaplasmosis (HGA) or Lyme disease, which are both endemic in Connecticut.

Laboratory Interpretation

The patient's EBV serologic pattern (IgM <36, IgG >600, nuclear Ab >600) indicates past EBV infection rather than acute infection, which would typically show elevated IgM antibodies. This pattern suggests that EBV is not the cause of his current symptoms.

Treatment Recommendation

1. Initiate doxycycline immediately at 100 mg twice daily for adults for a minimum of 5-7 days 1

   • Treatment should continue for at least 3 days after fever subsides and until evidence of clinical improvement
   • Do not delay treatment waiting for laboratory confirmation, as this can lead to severe disease and potentially fatal outcomes

2. Avoid sulfa-containing antimicrobials as they are associated with increased severity of tick-borne rickettsial diseases 1

3. Do not use amoxicillin alone for suspected anaplasmosis, as it was ineffective in a similar case where a patient with suspected Lyme disease was treated with amoxicillin and probenecid but died from undiagnosed anaplasmosis 2

Monitoring and Follow-up

• The patient should show clinical improvement within 24-48 hours of starting doxycycline
• Persistent fever beyond 48 hours suggests an alternative diagnosis or treatment failure 1
• Follow-up laboratory testing may be warranted to monitor resolution of symptoms

Important Considerations

• Up to 40% of patients with tick-borne diseases do not recall a tick bite, so the patient's documented tick bite history is particularly significant 2
• In regions where both Lyme disease and anaplasmosis occur (like Connecticut), distinguishing between these diseases in early stages is difficult 2
• Doxycycline is effective against multiple tick-borne pathogens including Borrelia burgdorferi (Lyme disease), Anaplasma phagocytophilum, and Ehrlichia species 2, 1

Prevention Strategies

Advise the patient to:

1. Limit exposure to ticks during peak periods (April-September)
2. Inspect body and clothing thoroughly after being in wooded areas
3. Remove attached ticks immediately using tweezers or tick removal devices
4. Apply insect repellent (e.g., DEET) when in wooded or grassy areas 2, 1

Prophylactic antibiotic therapy is not generally recommended for asymptomatic patients with recent tick bites, but this patient is already symptomatic and requires full treatment 1.