Dasatinib is a potent tyrosine-kinase inhibitor which is used for chronic myeloid leukemia treatment. Pleural effusion is a frequent side effect in patients during dasatinib treatment. Pulmonary arterial hypertension is a rare and life-threatening adverse event of dasatinib. The relationship between dasatinib and autoimmune disorders is unclear, but there are reports of possible mechanisms that have triggered autoimmunity by dasatinib.A 53-year-old male was diagnosed with chronic myeloid leukemia and initiated imatinib mesylate as a treatment. Imatinib was changed to dasatinib as the patient was unresponsive in the first year of treatment. In the fourth year of dasatinib when chronic myeloid leukemia was in both hematological and cytogenetical remission, the patient presented with bilateral massive exudative pleural effusion. Echocardiography was consistent with pericardial effusion with right ventricle enlargement and normal left-side cardiac function. Pulmonary arterial hypertension was diagnosed with high systolic pulmonary arterial pressure. When he had fever and arthralgia, further investigation showed positivity of anti-nuclear antibodies (1/160 titer) and anti-RNP/Sm, which have high specificity for the diagnosis of Systemic Lupus Erythematosus (SLE).Dasatinib was discontinued and nilotinib was initiated. As the pleural effusion persisted despite diuretics and methylprednisolone, mycophenolate mofetil was initiated as a steroid-sparing immune-suppressive agent. The lupus-like symptoms disappeared, and antibodies became undetectable after dasatinib discontinuation. Pericardial effusion improved and pleural effusion did not relapse.Screening for auto-antibodies may be recommended for patients with a history or symptoms of autoimmune disease before starting dasatinib. All patients who develop pleural effusion while on dasatinib treatment should be investigated for antibodies for lupus.
