The New England Journal of MedicineGoing Down the Rabbit Hole

Oropharyngeal Tularemia: A Rare Zoonotic Infection Mimicking Common Pharyngitis

This case report details the diagnosis and treatment of oropharyngeal tularemia in an 8-year-old girl. The patient’s prolonged fever, pharyngitis, and cervical lymphadenopathy initially misdiagnosed as bacterial pharyngitis highlight the importance of thorough history-taking and maintaining a broad differential diagnosis when patients do not respond to initial antibiotic therapy.

Key Points:

• The patient presented with a 12-day history of fevers and sore throat, initially misdiagnosed as bacterial pharyngitis.
• Multiple courses of antibiotics, including amoxicillin and doxycycline, failed to resolve symptoms.
• CT imaging showed extensive peritonsillar edema and cervical lymphadenopathy.
• A detailed exposure history revealed contact with dead rabbits, tick bites, and ingestion of well and spring water.
• The patient was empirically treated with intravenous gentamicin for presumed tularemia.
• Symptoms improved after 48 hours of gentamicin treatment.
• F. tularensis antibody test was positive at a titer of 1:1280, confirming the diagnosis.
• Oropharyngeal tularemia is rare in the United States, often occurring after ingestion of contaminated food or water.
• Tularemia manifests in six clinical syndromes: ulceroglandular, glandular, oculoglandular, oropharyngeal, pneumonic, and typhoidal.
• Definitive diagnosis requires isolation of the organism or a four-fold change in serum antibody titer.
• Gentamicin is the preferred treatment for severe tularemia in both adults and children.
• Ciprofloxacin and doxycycline can be used for milder cases or to complete therapy after initial improvement with gentamicin.
• Climate change may increase the geographic range and incidence of tularemia and other zoonotic diseases.
• Delayed diagnosis and treatment (beyond 16 days of illness) increase the likelihood of clinical failure and may necessitate surgical intervention.

Tularemia cases in the US peaked at 314 in 2015, with Colorado reporting 52 infections. Fast forward to 2022, and the CDC recorded 167 cases nationwide, with Kansas leading at 27 reports. It’s a reminder that even rare diseases can have surprising spikes.

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