Colobronchial fistula: the pathogenesis, clinical presentations, diagnosis and treatment.

Background: Colobronchial fistula (CBF) is rare and easy to be delayed in clinic. There is no systemic study about this disease. The pathogenesis, clinical presentations, diagnosis and treatment of CBF were analyzed in this study.

Methods: The clinical data from 37 cases of CBF, which included one case in our institute and the other 36 cases in literature from January 1960 to August 2016, were reviewed and analyzed. The etiology, clinical presentations, diagnostic and therapeutic methods, and outcomes were summarized.

Results: The causes of CBF included Crohn's disease, postoperative intraperitoneal adhesion, diaphragmatic hernia, pulmonary infection or abscess, colonic malignancy, colonic interposition, radiation, hyperthermic intraperitoneal chemotherapy (HIPEC), diaphragmatic mesh repair, pulmonary tuberculosis and pyonephrosis. Based on the anatomical location and the causes of fistula, CBF were divided into four types: type I, CBF secondary to the adhesion among colon, diaphragm and lung; type II, CBF secondary to diaphragmatic hernia; type III, CBF secondary to sub diaphragmatic abscess or emphysema; type VI, CBF secondary to colon interposition. The characteristic clinical presentations of CBF was productive cough with foul smelling sputum (78.38%), most of the patients were finally confirmed the diagnosis by barium enema or water-soluble contrast enema study (67.57%) and computer tomography (CT) scan/with multiplanar reconstruction (16.22%); 35 cases (94.59%) accepted the surgical treatment. Among 31 patients with recorded follow-up data, 26 patients recovered unevenly, but 5 patients died in 1 month after treatment.

Conclusions: CBF is a rare but can not be ignored disease. Anything which may induce the direct or indirect connection between colon and lung tissue may result in CBF. Productive cough with foul smelling sputum is the characteristic symptom. Radiological investigations such as barium enema and/or CT scan with multiplanar reconstruction are valuable for the confirmation of CBF. Surgery based on the etiology is the foundation of treatment.