["Not everything that looks like a tumor..." - Pulmonary tularemia with hilar lymphadenopathy]

Tularemia is a rare zoonotic disease caused by Francisella tularensis, whose pulmonary manifestations occur only sporadically in Central Europe and can be particularly challenging to diagnose.

We report on a 58-year-old patient presenting with B-symptoms in whom a thoracic mass was detected on computed tomography.

Further imaging studies revealed a metabolically active mediastinal mass with lymphadenopathy, suggestive of bronchial carcinoma. Only surgical mediastinoscopy with evidence of granulomatous-histiocytic inflammation, as well as further infectious disease diagnostics, led to the diagnosis of pulmonary tularemia.

Following a 20-day course of doxycycline, there was rapid clinical improvement and complete laboratory and radiological regression of the lymphadenopathy.

This case underscores that pulmonary tularemia can resemble malignant processes morphologically and metabolically. Early consideration of infectious disease differential diagnoses, as well as the combination of histology, serology, and molecular biological methods, are crucial to avoid misdiagnoses and unnecessary invasive procedures.