(1158) From Treatment to Trauma: The Unexpected Case of Dasatinib-Induced Diffuse Alveolar Hemorrhage

Introduction: Dasatinib is a 2nd generation tyrosine kinase inhibitor used for the treatment of chronic myeloid leukemia (CML). Common pulmonary toxicities include pleural effusions, lung parenchymal abnormalities, and pulmonary hypertension. Diffuse alveolar hemorrhage (DAH) is very rare. DAH is a clinical pathological syndrome characterized by accumulation of red blood cells in the alveolar space. Here we report a case of a patient who developed DAH while on dasatinib leading to acute hypoxemic respiratory failure.

Description: 71-year-old female with history of CML on treatment with dasatinib presented with shortness of breath, cough and hemoptysis. The patient was in acute respiratory failure requiring intubation. Chest auscultation revealed diffuse coarse crackles bilaterally. Lab work showed white cell count 9900 cells/ul, hemoglobin 10 mg /dl, platelets 193000 /ul. Chest x ray revealed bilateral opacities and CT chest was significant for worsening bilateral airspace opacities suggestive of diffuse pulmonary hemorrhage. Bronchoscopy findings were consistent with alveolar hemorrhage. Pathology of the bronchoalveolar lavage showed abundant benign macrophages and red blood cells, no malignant cells. ANA, c-ANCA, p-ANCA, anti GBM antibody were negative. The diagnosis of dasatinib-induced DAH was made, and the drug was stopped. She was started on high dose methylprednisolone for 7 days and her condition progressively improved.

Discussion: Diffuse alveolar hemorrhage is an extremely rare manifestation of dasatinib induced pulmonary toxicities. It is essential to identify the underlying cause of DAH to initiate appropriate treatment and prevent acute respiratory failure and death. Drugs that are often reported to induce pulmonary hemorrhage consist of anticoagulants, propylthiouracil, amiodarone, and methotrexate. But dasatinib induced DAH is very unusual and the suggested cause of this pulmonary complication is the inhibition of platelet derived growth factor, participation of large granular lymphocytes, alveolar epithelial and interstitial damage, however the exact mechanism is not known. Dasatinib even though well tolerated, it is essential to be aware of its pulmonary toxicities, especially in patients with deteriorating respiratory status with no other obvious cause.