Tularæmi hos to patienter henvist på mistanke om cancer mammae og cancer occulta

Tularaemia (rabbit fever) is a rare infection caused by Francisella tularensis, which can be transmitted from hares and rats to humans by ticks. We present two case reports of patients with tularaemia. Both were initially referred on suspicion of cancer. A 52-year-old woman, who had had a prior tick bite, was referred on suspicion of breast cancer, and a 28-year-old man was referred on suspicion of occult cancer because of fever and lymphadenopathy in the groin. Tularaemia should be considered as a differential diagnosis in cases of unexplained fever and regional lymphadenopathy, especially in patients with a history of tick bites.