We present a case of a 34 year-old male diagnosed with ankylosing spondylitis. After two years of treatment with infliximab, the patient developed a clinical picture compatible with stage II thoracic sarcoidosis. These findings resulted in the interruption of infliximab therapy. The patient was not administered new treatment since respiratory function testing did not confirm harmful repercussions. After a follow-up of 1 year, the patient is asymptomatic and radiologic tests show complete resolution of pulmonary infiltrates and mediastinal and bilateral hilar lymphad- enopathy.