Isolated anterior mediastinal tuberculosis in an immunocompetent patient

The differential diagnosis of a mediastinal mass is a common challenge in clinical practice, with a wide range of differential diagnosis to be considered. One of the rarer causes is tuberculosis. Atypical presentations of tuberculosis are well documented in immunocompromised patients, but should also be considered in the immunocompetent.

This case outlines a previously healthy 22 year-old immunocompetent male presenting with worsening chest pain, positional dyspnea, dry cough and dysphagia. Chest x-ray showed evidence of an isolated anterior mediastinal mass, which was confirmed on computed tomography. A mediastinoscopy was diagnostic as histology revealed necrotizing granulomatous inflammation and the presence of acid-fast bacilli, indicating mediastinal tuberculosis.

Typically the underlying presentation of mediastinal tuberculosis is mediastinal lymphadenitis. This case was unusual in that we detected an isolated large anterior mediastinal mass accompanied by a relatively small burden of mediastinal lymphadenitis. Cases similar to this have been documented in immunosuppressed patients however in our case no evidence of immunosuppression was found. This case report emphasizes the importance that a detailed and logical pathway of investigation is pursued when encountering a mediastinal mass.