Rituximab-induced lung disease (R-ILD) is a rare entity that should be considered in patients treated with rituximab who present with dyspnea, fever, and cough but no clear evidence of infection. We describe the clinical presentation, management, and response to rechallenge in one mantle cell lymphoma patient who developed R-ILD during maintenance rituximab.

Case report

66 years old male with history of mantle cell lymphoma (MCL), who had been treated with RCHOP and underwent autologous stem cell transplantation (ASCT), was diagnosed with relapse 5 years after ASCT. Six courses of rituximab-bendamustine resulted in 2nd complete response and 2-monthly rituximab maintenance was initiated.10 days after 3rd rituximab , he presented with a 1 week history of progressive exertional dyspnea and cough. He was tachypneic and hypoxemic.

Thorax HRCT showed peripheral bilateral patchy ground glass opacities and nodular opacities. Bronchoalveolar lavage identified no bacterial,viral or fungal pathogen. With presumptive diagnosis of late R-ILD, methylprednisolone(MP) 1 mg/kg/day was started. In absence of rapidly progressing respiratory failure and fever, the patient was evaulated as non severe R-ILD. Thus, rechallenge with rituximab is being considered due to the risk of relapse of MCL.

Discussion: Reported rate of possible R-ILD is <0.03% in over 540,000 patients. Pulmonary complications of rituximab are hypersensitivity pneumonitis, ARDS, interstitial pneumonitis, organizing pneumonia, pulmonary fibrosis, and alveolar haemorrhage. Symptoms of R-ILD are dyspnea, fever, and hypoxemia and HRCT findings include focal alveolar densities, ground glass opacities and alveolar opacification. Time to symptom onset ranges from 1 day to several weeks after 1st infusion with mean

mean duration of 3 months. Our patient had received rituximab prior to relapse and developed R-ILD after 9 doses of rituximab for relapse, which is a rare finding. All other causes of potential lung injury had to be meticulously excluded. ILD is a rare but potentially fatal pulmonary toxicity due to rituximab. As the symptoms at presentation are nonspecific, physicians must maintain a high index of suspicion to recognize it early and initiate treatment to avoid severe morbidity and mortality.