Ankylosing spondylitis (AS) is a chronic inflammatory dis-order, commonly characterized by inflammation of axial skeleton and development of enthesopathies. Tumor ne-crosis factor inhibitors (TNFi) shows good therapeutic re-sponses in AS patients without good response to non-ster-oidal anti-inflammatory drugs. Although TNFi are rela-tively safe for AS patients, serious opportunistic infections, including tuberculosis and fungal infection, could develop. Here, according to our knowledge, we report a first Korean case of pulmonary cryptococcosis in a patient with AS treated with etanercept. A 64 year-old man with AS visited due to a newly appeared pulmonary nodule on a routine chest radiography. He had been administered eta-nercept for 5 months. Histologic findings of the lung nod-ule showed characteristic features of cryptococcosis. Etanercept was discontinued and oral fluconazole was ad-ministrated, as there was no evidence of central nervous system involvement. After 7 months of treatment, chest CT showed an improvement of the pulmonary lesion.

Keywords: Ankylosing spondylitis, Pulmonary crypto-coccosis, Etanercept, Tumor necrosis factor inhibitor