P1‐69: Acquired esophago‐airway fistula in adults: A case report

breath sounds over the right lung base. CT chest showed right lower lobe lung mass with loculated pleural effusion. He was also diagnosed with dermatomyositis based on characteristic skin rash, proximal muscle weakness, elevated muscle enzymes and compatible electromyography changes. Pleural fluid workup was positive for tuberculosis (TB). However, malignancy was still a concern given its strong association with dermatomyositis. As pleural fluid cytology and percutaneous biopsy of the lung mass was unrevealing, he underwent a surgical lung biopsy and the histology showed hyalinizing granuloma. The lung mass persisted despite completion of anti-TB drugs, and a repeat biopsy was again negative for malignancy. With time, he demonstrated the more classical radiological features of silicosis, with diffuse small nodules and eggshell calcification of mediastinal lymph nodes. Reexamination of the lung mass histology showed palisading granulomas and necrosis with many polarisable particles, which turned out to be silicon dioxide on spectral analysis. Detailed occupation history revealed significant silica exposure in the construction industry. A diagnosis of progressive massive fibrosis was made. This case illustrates the association between silicosis, TB and dermatomyositis. Silicosis increases the risk of TB by two-to-three-fold. Silicosis is also associated with dermatomyositis, though this association is rare, with less than ten cases reported, and postulated to be related to dysregulation of autoimmunity. This case brings to awareness how these seemingly unrelated conditions are in fact connected.