Tuberculosis presenting with pneumomediastinum

A 32 yr old male^† presented to the Emergency Department of All India Institute of Medical Sciences, New Delhi, in December 2019 with fever, dry cough and anorexia since one month. He had right-sided chest pain and dyspnea for a few days and suffered from poorly controlled diabetes mellitus for one year. On examination, the pulse rate was 120/min (no pulsus paradoxus), respiratory rate was 28/min and SpO₂ at room air was 78 per cent. An arterial blood gas revealed an alveolar-arterial oxygen gradient of 46 mmHg. The cardio-respiratory examination demonstrated palpable neck crepitus, faint heart sounds and right infrascapular crepts. Blood sugar at presentation was 326 mg/dl, and insulin infusion was started for management. Computed tomography of the thorax (Figure) demonstrated bilateral consolidation with the right lower lobe cavity (arrowhead) and pneumomediastinum (red arrow). Bronchoalveolar lavage demonstrated acid-fast bacilli, and a diagnosis of pulmonary tuberculosis was achieved. He was initiated on standard four-drug antitubercular therapy, and pneumomediastinum decreased spontaneously. He had clinical improvement at eight weeks of follow up and was shifted to three drugs.

Figure: Computed tomography thorax demonstrating cavitary lesion in the lower lobe of the right lung (yellow arrowhead) and air around the heart (red arrow) suggesting a diagnosis of pneumomediastinum.

Pneumomediastinum occurs due to intrapulmonary rupture of alveoli and spreads along the vascular bundle. It is an unusual presentation of pulmonary tuberculosis and is generally seen in cavitary disease. The presence of pneumomediastinum in a patient with lung lesions should prompt investigation for tuberculosis.

Conflicts of Interest: None.