Tuberculosis presenting as isolated bronchonodal fistula in a patient with systemic lupus erythematosus

Rationale Lymph node is a preferred site for extrapulmonary tuberculosis (TB). In the thorax, mediastinal tuberculous lymph nodes can erode adjacent structures such as heart, aorta, and esophagus, forming fistula, and causing fatal consequences. However, tuberculous bronchonodal fistula as a complication of lymph node TB in adults is rarely known in terms of imaging or clinical findings. Here, a case of isolated tuberculous bronchonodal fistula appearing as the first presentation of TB in a 74-year-old male with systemic lupus erythematosus (SLE) is reported. Patient concern A 74-year-old male with SLE visited the hospital with dry cough. In family history, his son was treated for pulmonary TB 9 years previously. Laboratory test revealed increased C-reactive protein level and erythrocyte sedimentation rate. Chest computed tomography (CT) scan revealed a necrotic lymph node in the right hilar area connected to the inferior wall of the right upper lobe bronchus and the lateral wall of bronchus intermedius. Diagnoses On bronchoscopy performed under guidance of 3-dimensionally reconstructed CT image, fistula formation between the right hilar lymph node and 2 bronchi (the right upper lobe and intermediate bronchus) was confirmed. Sputum culture revealed growth of Mycobacterium tuberculosis. Intervention Anti-TB medication with isoniazid, ethambutol, pyrazinamide, and moxifloxacin for 9 months. Outcome The patient's symptom was gradually improved. Follow-up bronchoscopy performed at 3 months after starting the medication revealed decreased size of the fistula. Lessons This is a rare case of bronchonodal fistula appearing as the first presentation of TB in a 74-year-old male patient with SLE. CT provided useful information regarding the origin and progress of the disease.