Fever of unknown origin: a case of post obstructive pneumonia complicating mature teratoma.

Mediastinal teratomas are rare germ cell tumors in children accounting for only 4.3% of all germ cell tumours. Here, we describe a three year old child who was misdiagnosed as a case of pulmonary tuberculosis at periphery despite of his chest X ray showing large homogenous opacification of left hemithorax with areas of calcifications and subsequently diagnosed as a case of benign mature teratoma with post obstructive pneumonia. Our case highlights the need for careful evaluation of chest X-ray (CXR) by the treating physicians, especially when CXR had a large homogenous opacity with shifting of mediastinum and presence of a few calcified shadows, which may clinch a rare diagnosis of an uncommon disorder.