B-cell acute lymphoblastic leukemia associated with hypereosinophilia: a case report and brief literature review.

Few cases of B-cell acute lymphoblastic leukemia (B-ALL)-eosinophilia (ALL-eo) association have been reported. The lack or absence of blasts in the peripheral blood smear (PBS) along with urticarial rash, fever, arthralgia, myalgia, sweating, and dyspnea are common features of this condition. Herein, we report a 16-year-old male patient admitted to the emergency department with urticaria and generalized itching. PBS was examined, and eosinophils (90%) were seen in different fields. However, blast cells were not seen in PBS. In a bone marrow examination, terminal deoxynucleotidyl transferase-positive and CD20-positive lymphoid blasts were reported along with eosinophilia. Eventually, the B-ALL diagnosis was confirmed for the patient, and he was started on the Berlin-Frankfurt-Münster chemotherapy regimen. The association of B-ALL with hypereosinophilia is a rare condition. We hope this case report and literature review can help clinicians to manage this rare condition properly.