대한흉부영상의학회 Korean Society of Thoracic Radiology

Discussion

Diagnosis With Brief Discussion

Diagnosis

Esophago-Nodo-Bronchial Fistula due to Tuberculosis

Radiologic Findings

Chest radiograph demonstrates a widening of the right paratracheal stripe and calcified lymph node in the right paratracheal region. Chest CT scans show lymphadenopathy in the right lower paratracheal, left paraesophageal, subcarinal and left hilar nodal stations. There is air density within the left paraesophageal lymph node. Note extrinsic compression and luminal narrowing of the left main bronchus due to the enlarged left paraesophageal lymph node. Esophagography shows a barium filled pouch (open arrows) that communicates with the esophagus and left main bronchus.

On endoscopy, there was a wall defect in the esophagus, about 25cm to 27 cm from the incisor. When the scope was advanced through the defect, yellowish and round mass was noted in the cavity.

Brief Review

Esophageal involvement by tuberculosis usually occurs in the late stages of tuberculosis secondary to pulmonary, mediastinal, or disseminated disease (1-2). Direct contiguous involvement from adjacent tuberculous lymphadenitis is known to be the most frequent cause of esophageal tuberculosis (2-3). As the tuberculous process involves mediastinal lymph nodes, they enlarge because of caseation necrosis and granulation tissue. Necrotic material within the tuberculous mediastinal lymph node can be extruded through an esophageal and/or tracheoesophageal fistula, resulting in a localized gaseous collection within the mediastinum.
The most common sites of involvement in tuberculous mediastinal lymphadenitis are the right paratracheal, tracheobronchial and subcarinal areas (4-6). However, according to Lim at al (7), the most common site of esophagomediastinal fistula located in the subcarinal area. Preferential involvement occurs mainly because of the anatomic proximity of the esophagus to diseased nodes. Even though tuberculous lymphadenitis involves the right paratracheal nodes more commonly than the subcarinal nodes, as the diseased right paratracheal nodes have less chance to contact the esophagus directly than the subcarinal nodes, fistulous communication is more prone to occur in the subcarinal area.
Acquired benign bronchoesophageal fistulas in the adult usually occur by granulomatous infection, most commonly tuberculosis. Several mechanisms have been proposed for the pathogenesis of inflammatory bronchoesophageal or tracheoesophageal fistula: 1) Caseonecrotic parabronchial enlarged nodes may rupture into the esophagus and the trachea; 2) primary tracheal ulcers may erode into adjacent esophagus; or 3) infection may give rise to adhesions between tracheobronchial lymph nodes and the neighboring esophagus with subsequent development of a traction diverticulum. A traction diverticulum may communicate with the respiratory tree (3).

References

1. Lockard LB. Oesophageal tuberculosis: a critical review. Laryngoscope 1913; 23:561-83
2. Rubinstein BM, Pastrana T, Jacobson HG. Tuberculosis of the esophagus. Radiology 1958; 70:401-403
3. Spalding AR, Burney DP, Riche RE. Acquired benign bronchoesophageal fistula in the adult. Ann Thorac Surg 1979; 28:378-383
4. Im J-G, Song KS, Kang HS, et al. Mediastinal tuberculous lymphadenitis: CT manifestations. Radiology 1987; 164:115-119
5. Amorosa JK, Smith PR, Cohen JR, Ramsey C, Lyons HA. Tuberculous mediastinal lymphadenitis in adult. Radiology 1978; 126:365-368
6. Liu C-I, Fields WR, Shaw C-I. Tuberculous mediastinal lymphadenopathy in adults. Radiology 1978; 126:369-371
7. Im J-G, Kim JH, Han MC, Kim C-W. Computed tomography of esophagomediastinal fistula in tuberculous mediastinal lymphadenitis. JCAT 1990; 14:89-92

Keywords

Esophagus, Airway, Infection, fistula,