Progressive dyspnea and diffuse ground‐glass opacities after treatment for lymphoma with rituximab‐containing chemotherapy: A case report

A 49‐year‐old man presented to our outpatient clinic complaining of nonproductive cough and exertional dyspnea for two months. He had been diagnosed with large B cell non‐Hodgkin's lymphoma seven months previously, and the tumor had almost disappeared after four cycles of rituximab‐containing chemotherapy. He then developed a severe dry cough, progressive dyspnea and hypoxia two weeks after the fifth cycle. Bilateral diffuse ground‐glass opacities were visible on chest X‐ray. Although the patient's symptoms were ameliorated temporarily after two weeks of methylprednisolone administration and multiple antibiotics, exertional dyspnea had progressed slowly starting one month after discontinuation of the corticosteroid. A repeat chest computed tomography (CT) scan showed diffuse ground‐glass opacities, bronchoalveolar lavage fluid tests for pathogens were negative and the pathological manifestation of the transbronchial lung biopsy showed nonspecific interstitial pneumonia. Rituximab‐induced interstitial lung disease was diagnosed after multidisciplinary discussion. Prednisone was again prescribed and his symptoms and the pulmonary opacities gradually disappeared. Although various pulmonary infections are the most common respiratory complications in patients with non‐Hodgkin's lymphoma undergoing rituximab‐containing chemotherapy, noninfectious diffuse lung disease, eg, drug‐associated interstitial lung disease might be considered as a differential diagnosis of patients treated with rituximab, especially if a patient is nearing the time of administration of a fourth cycle of rituximab.