Pulmonary arteriovenous fistula (PAVF) is an abnormal connection betwe
en pulmonary arteries and veins. Patients with PAVF may have the Rendu
-Osler-Weber syndrome, a disease transmitted by autosomal dominant mec
hanisms. Here we describe a. case of PAVF in a 56-year-old women, who
was admitted to our department because of dyspnea, hemoptysis, and a m
ass in the left lower lung found on chest X-ray, The diagnosis of PAVF
was suspected according to clinical and physiological criteria and co
nfirmed by magnetic resonance imaging of the chest, The PAVF was remov
ed by left lower lobectomy. Anamnestic and clinical investigations of
the patient's relatives led to the diagnosis of the Rendu-Osler-Weber
syndrome.