Pleural effusion revealing a ruptured mediastinal mesothelial cyst.

Mesothelial cysts are uncommon benign cysts of the mediastinum. Rarely, they are discovered after complications or unusual presentations. This report describes a rare case of pleural effusion revealing a ruptured mediastinal mesothelial cyst in a 28-year-old man. The diagnosis of this complicated mesothelial cyst relied on intraoperative and anatomopathological findings. He underwent videothoracoscopy with resection of the cyst. Outcomes were favourable.