An Uncommon Case of Tularaemia in Portugal after an Arthropod Bite

Tularaemia is a rare zoonosis caused by Francisella tularensis, with only a few reported cases in Western Europe and only 4 notified in Portugal between 2014 and 2021. We describe an imported case diagnosed in Portugal in 2023. A 40-year-old female developed a painful left inguinal lymphadenopathy after an arthropod bite in England. Despite initial treatment with doxycycline, symptoms persisted with systemic manifestations and progressive lymphadenopathy. Serology tests confirmed F. tularensis infection. The patient required prolonged follow up and antibiotic adjustment, showing gradual clinical improvement. This case highlights the diagnostic challenges of tularaemia and the importance of thorough physical examination and epidemiological history.

Diagnosing and differentiating zoonosis presents a challenge, since it is important to remember even the rarer and imported ones, such as tularaemia.Once the diagnosis is made, the clinical condition and treatment of the patient may not evolve as expected, being important for the clinician to adjust to new findings.