# When Teratoma Masquerades: A Rare Case of Intrapleural Mature Cystic Teratoma Mimicking Tuberculous Empyema

## TL;DR

A rare case of a mature cystic teratoma in the pleura was mistaken for a recurring tuberculous empyema, highlighting the importance of accurate diagnosis.

## Contribution

This paper presents a rare clinical case of intrapleural mature cystic teratoma mimicking tuberculous empyema.

## Key findings

- The patient's pleural effusion was initially suspected to be tuberculous but was later diagnosed as a mature cystic teratoma.
- Histopathological analysis confirmed the diagnosis after imaging and initial treatments failed to resolve the condition.
- The case emphasizes the diagnostic challenges posed by rare teratomas masquerading as more common diseases.

## Abstract

Teratomas are germ cell tumours generally gonadal in origin and very rare, arising from extra gonadal tissue. The most common extragonadal teratomas are mediastinal, and the majority are benign. We report a case of a 49‐year‐old lady with recurrent right complex pleural effusion occurring a month after the completion of treatment for tuberculous empyema. Imaging from ultrasound of the thorax and contrasted enhanced computed tomography (CECT) thorax revealed multiseptated and loculated effusion in the thorax without any mediastinal and lung involvement. Surprisingly, pleural fluids were negative for tuberculosis. Despite chest drainage and initial treatment for bacterial empyema without improvement, she underwent video assisted thoracoscopy and decortication of the right pleura, and histopathological analysis revealed a mature cystic teratoma. She was discharged in good health and under yearly surveillance. The rarity of intrapleural mature cystic teratoma and its misleading presentation due to the concurrent tuberculous empyema make this case noteworthy.

We report a case of a 49‐year‐old lady with recurrent right complex pleural effusion occurring a month after completed treatment of tuberculous empyema. Imaging and diagnostic work‐up revealed a mature cystic teratoma. The rarity of intrapleural mature cystic teratoma and its misleading presentation due to the concurrent tuberculous empyema makes this case noteworthy.