Four cases of bronchiolitis obliterans organizing pneumonia associated with thyroid disease.

We present 4 cases of bronchiolitis obliterans organizing pneumonia (BOOP) associated with thyroid diseases. Case 1 had previously undergone surgery for thyroid cancer, and had a secondary hypothyroidism at the onset of BOOP. Case 2 developed Basedow's disease 3 months after the onset of BOOP and BOOP relapsed 21 months after the onset of Basedow's disease. Case 3 developed subacute thyroiditis 33 months after the onset of BOOP, and has had no relapse of BOOP for 7 years. Case 4 had hypothyroidism at the time of diagnosis of BOOP, and her BOOP relapsed 3 months after the initial onset of BOOP. Two of these 4 cases of BOOP with thyroid diseases relapsed, and thyroid dysfunction could modify the pathophysiology of BOOP.