Differentiation Syndrome with Severe Abdominal Pain During Induction Treatment of Acute Promyelocytic Leukemia: A Case Report

The survival rate of acute promyelocytic leukemia (APL) has been significantly improved since all-trans-retinoic acid (ATRA) and arsenic trioxide (ATO) were introduced into chemotherapeutic regimens.1 However, some severe treatmentrelated complications, such as intracranial bleeding, differentiation syndrome (DS), and other ATRA- and ATO-related toxicities, limit the therapeutic effect.2 DS often occurs in APL patients when they are undergoing induction therapy with ATRA and/or ATO.3 Presenting symptoms of APL DS are diverse but are frequently characterized by unexplained fever, dyspnea with pulmonary infiltrates Background: Acute promyelocytic leukemia differentiation syndrome (APL DS) is a common and severe complication seen in patients with APL treated with all-trans retinoic acid (ATRA) and/or arsenic trioxide (ATO). The presenting symptoms of APL DS are diverse, and rare symptoms are easy to be misdiagnosed. Therefore, it is very crucial to identify DS from uncommon signs to avoid delay in treatment. Case Presentation: Here, we report a patient of APL who developed severe abdominal pain during ATRA and ATO therapy, with increasing leukocyte count. Organic diseases were firstly excluded, and empiric treatment for DS was adopted. The abdominal pain was gradually relieved and the patient eventually achieved complete remission. Conclusion: This case history suggests that APL DS may manifest as severe abdominal pain, and the early identification of DS and immediate treatment could improve the prognosis of patients.