This study aimed to evaluate the diagnosis, treatment and clinical monitoring of the patients with sarcoidosis and to determine their general characteristics. MATERIAL AND METHODS: We retrospectively examined demographic, clinical, laboratory and radiological findings of 100 patients who were followed-up with the diagnosis of sarcoidosis in Gazi University of Faculty of Medicine, Department of Chest Disease between 1994 and 2010. RESULTS: Mean age of the patients was 44±12 years (22-82), female/male ratio was 2.8 and no difference of the age at diagnosis was found between the genders. Most commonly seen complaints included dyspnea, cough and skin disorders. It was reported that 50% of the men and 17% of the women had a history of smoking and that smokers were presented at advanced stages (Stage 2-3) (p=0.006). Three percent of our patients had familial sarcoidosis. It was seen that 96% of the patients had pulmonary tomography at the time of diagnosis. No correlation was detected between angiotensin-converting enzyme (ACE), erythrocyte sedimentation rate and serum and urine calcium levels and the disease stage. Of the patients, 34% showed impaired respiratory function test (RFT) results and 49% showed decreased diffusing capacity of carbon monoxide (DLCO) values, most commonly with restrictive pattern, at the time of diagnosis. Forced expiratory volume in 1 second (FEV 1), forced vital capacity (FVC) and decreased DLCO values did not show a correlation with the stage of the disease (p<0.01). Of our patients, 16% were diagnosed with sarcoidosis based on clinical, laboratory and radiological findings, whereas other patients underwent some invasive interventions for tissue diagnosis. Most commonly used invasive methods included transbronchial biopsy (34%), punch biopsy (31%), mediastinoscopic or transbronchial mediastinal lymph node biopsy (22% and 9%, respectively). During the follow-up period, 43% of the patients received treatment. During the follow-up, 18 patients (18%) showed relapse in the period after the diagnosis. It was seen that relapse was more common in the patients with advanced stage, who have received treatment at the time of diagnosis (p<0.01 and p=0.04). CONCLUSION: Sarcoidosis is a multisystemic disease that may have a course with several clinical findings and that should be absolutely considered in the differential diagnosis with its commonly or rarely observed findings.