Thoracic melioidosis: a diagnostic dilemma.

The diagnosis of melioidosis can be difficult, and it is frequently described as "the great mimicker". We report a case of thoracic melioidosis presenting as a mediastinal mass with impending superior vena cava obstruction. With the presumptive diagnosis of mediastinal tumor, the patient underwent surgery for tissue sampling, and a purulent collection was found. The clinical syndromes of melioidosis and the diagnostic dilemma are discussed.