[Asymptomatic pulmonary actinomycosis diagnosed by transbronchial lung biopsy (TBLB)].

A 65-year-old asymptomatic man was admitted to our hospital because a chest abnormal shadow had been pointed out on a medical examination. Our investigation resulted that the consolidation in the left lung had been initially documented in 2002, and had been expanding every year. Bronchofiberscopy showed flare, swelling and stenosis of the left B8, B9 and B10. Because the biopsy specimen from the B9 showed a mass of bacteria and surrounding granulation tissue, pulmonary actinomycosis was diagnosed. Pulmonary actinomycosis should be considered in the differential diagnosis of abnormal chest shadows regardless of the absence of symptoms.