Two Cases of Interstitial Pneumonitis Caused by Rituximab Therapy
This 66-year-old man visited our hospital because of a right testicular mass (8×6 cm), which was detected one year prior to presentation and recently grew larger and became painful. After orchiectomy, the pathologic diagnosis was diffuse large B-cell lymphoma, stage IVA with unilateral involvement of bone marrow. He received five cycles of R-CEOP combination. His had a complete response after the 3rd cycle. After the 5th cycle of R-CEOP, he complained of cough and dyspnea, NYHA class II. Auscultation revealed end-expiratory Velcro-like rales at both lower lung fields. Chest computed tomography showed a markedly increased centrilobular and subpleural GGO and multiple consolidations in both lung fields (). Pulmonary function testing showed a mild obstructive pattern and decreased diffusing capacity with a FEV1; 1.95 L/min (76% of normal predicted value), FVC; 3.09 L/min (83% of normal predicted value), FEV1/FVC; 63%, and DLCO; 10.8 mL/mmHg/min (70% of normal predicted value). Bronchoalveolar lavage was refused by the patient. Symptomatic improvements were achieved two weeks after a prednisolone 10 mg qd daily regimen. After two months of steroid therapy, pulmonary function testing showed an objective response with a FEV1; 1.84 L/min (67% of normal predicted value), FVC; 3.33 L/min (83% of normal predicted value), FEV1/FVC; 56%, and DLCO; 15.5 mL/mmHg/min (89% of normal predicted value). Chest computed tomography demonstrated improvement ()