An 8-month-old infant with hepatic tularemia: a case report

An 8‑month-old infant developed a fever of up to 40 °C, accompanied by vomiting and diarrhea, 1 day after a tick bite in the nuchal region; there was also local infection of the bite wound. Although treated with anti-inflammatory medication and antibiotics, the fever persisted. Sonography on day 10 of the fever showed multiple hypoechogenic abscesses in the spleen as well as lymphadenopathy in the upper abdomen, suspected of resulting from septic dissemination of the tick bite. After several tests to rule out any alternative disease etiologies yielded negative results, a lymphadenitis panel was positive for Francisella tularensis. Antibiotic therapy with ciprofloxacin was initiated accordingly. A repeat ultrasound showed new hypoechogenic lesions in the liver, in addition to those in the spleen. These were now determined to be granulomas caused by the infection with F. tularensis, consistent with previously reported cases. The patient was discharged on oral antibiotics 5 days after the diagnosis. At a follow-up appointment 1 week later, the patient's IgM antibodies against F. tularensis continued to decrease, while IgG levels continued to rise, confirming recent infection. After another 2 weeks of antibiotic treatment, the hepatic and splenic lesions had regressed significantly.