A 45-years-old immunocompetent man had abscess in right side of neck. It was complicated by mediastinitis and mediastinal abscess, acute kidney injury, transaminitis and DIC. CT neck and chest revealed features of mediastinitis and mediastinal abscess in continuation with right cervical lymphadenopathy and abscess. PCR for Mycobacterium tuberculosis was positive in pus drained from anterior mediastinum. We reported a rare manifestation of tuberculous mediastinitis and mediastinal abscess.