Imatinib Mesylate-Induced Interstitial Pneumonitis [1]

Indications:1 patient with metastatic gastrointestinal stromal tumor.

Patients:One 69 year old man. Temporary dropout.

TypeofStudy:A case report presenting Glivec induced interstitial pneumonitis that was treated successfully and on rechallenge was prevented with prednisone.

AdverseEffects:The patient developed interstitial pneumonitis manifested by nonproductive cough and progressive shortness of breath.

AuthorsConclusions:To our knowledge, our report represents the third published case of interstitial pneumonitis induced by imatinib. Our report is the first to use low-dose prednisone to prevent recurrence of imatinib induced interstitial pneumonia.

DosageDuration:400 mg orally for more than 8 months (with interruptions).

FreeText:The patient had no history of cardiopulmonary disorders and was diagnosed with metastatic gastrointestinal stromal tumor (GIST). Diagnostic imaging used for the pulmonary findings observed from the patient were chest x ray, computed tomographic (CT) angiogram of the chest and echocardiogram. Concomitant medication was prednisone given initially at 60 mg daily tapered to reach dosage of 9 mg daily.

Results:During the second week of treatment, the patient developed nonproductive cough and progressive shortness of breath. Findings on chest x-ray film, computed tomographic (CT) angiogram of the chest, and echocardiogram were unremarkable. However, the diffusion capacity was decreased to 63% predicted, compared to his baseline level of 87%. Glivec was discontinued because of the concern of drug-induced pulmonary toxicity. In the meantime, the patient was given levofloxacin. In the meantime, the patient was given levofloxacin. His respiratory symptoms improved the following day and resolved in about 1 week; they were attributed to an infectious etiology. 2 weeks later, Glivec was reinstituted. The next day, the patient experienced shortness of breath that progressively worsened, which prompted discontinuation of Glivec after 3 weeks of treatment. His oxygen saturation declined to 84% with 2 minutes of high-step exercise. A high-resolution CT scan revealed ground-glass infiltrates involving the mid and lower lungs bilaterally. The diffusion capacity was decreased substantially to 44% predicted, consistent with an interstitial lung process. Prednisone, 100 mg daily was instituted, tapered, and discontinued in 12 days. No antibiotics were given during this episode. The patients respiratory symptoms resolved in the next 2 days; a repeated high-resolution CT scan performed 2 weeks after the discontinuation of Glivec revealed resolution of interstitial infiltrates. The diffusion capacity returned to normal at 87% predicted. Despite the abbreviated therapy, the size of the liver metastases was clearly reduced on an abdominal CT scan. 3 months after discontinuation of Glivec, the patient developed progressive metastatic disease of the liver. Glivec was reinstituted. To prevent pulmonary reactions, prednisone, 60 mg daily was given during the initial 2 days, followed by 20 mg daily with subsequent tapering. The patient has been taking Glivec for about 7 months and is currently taking prednisone 9 mg daily. At last follow-up, the size of the liver lesions had decreased. The patient has had no respiratory symptoms or changes in the diffusion capacity.