Bronchial changes in airborne tularemia.

We describe seven typhoidal tularemia patients without ulcers or lymphadenopathy, who underwent diagnostic bronchoscopy. Four patients had had obvious airborne exposure to F. tularensis during farming activities, and the remaining three had respiratory symptoms also. Bronchoscopical findings were pathological in all cases, varying from local to diffuse haemorrhagic inflammation; in one case a granulomatous tumour was seen. Early histopathological changes in three biopsies consisted of haemorrhagic oedema progressing to a non-specific inflammatory reaction, which could still be found 45 days after the onset of symptoms. Granulomatous inflammation, indistinguishable from tuberculosis or sarcoidosis, was seen in four biopsies from two patients, three to seven months after the onset. Most patients had radiographic hilar enlargement. We conclude that transmission of typhoid tularemia usually occurs through inhalation leading to bronchial changes, which correspond skin ulcerations in ulcero-glandular tularemia, the hilar enlargement corresponding to the lymph node component. We emphasize that usage of the term 'typhoidal' tularemia should be discontinued. Instead, tularemia transmitted through inhalation should be called pulmonary or respiratory.