Anti- CCP antibody has recently gained much interest as a marker for early detection and prediction of severe articular and extra-articular disease in rheumatoid arthritis. To evaluate this in patients with active rheumatoid disease and lung involvement, we studied 40 rheumatoid arthritis patients with active disease: 10 patients (6 males and 4 females) have chronic disease with joint effusion but no extra articular affection, 13 chronic patients (5 males and 8 females) with joint effusions and evidence of lung fibrosis, 9 chronic patients (4 males and 5 females) with both joint and pleural effusions but no evidence of lung fibrosis and 8 patients (4 males and 4 females) with relatively recent onset disease with only joint inflammation without effusion plus 8 normal control subjects. Blood anti- CCP was found to be significantly much elevated in all patient groups than controls (p