2026 American Academy of Neurology Abstract Website

Objective:

This case emphasizes a rare but potentially fatal central nervous system complication of all-trans retinoic acid (ATRA) therapy in acute promyelocytic leukemia (APL).

Background:

APL is treated with ATRA which can lead to a treatment related complication called differentiation syndrome (DS). DS is characterized by massive release of pro-inflammatory cytokines, fever and hypotension.

Design/Methods:

Case Report

Results:

We present a case of a 51-year-old male who presented to the hospital with complaints of fatigue, mucosal bleeding and hematuria. His laboratory evaluation showed a WBC of 57K, PLT 9K and a peripheral smear with bi-lobed blasts and aurer rods, consistent with a diagnosis of APL. His mental status deteriorated in the ER and his CT Head revealed bi-hemispheric, multi-focal intraparenchymal hematomas with associated mass effect. He was intubated, transferred to the NICU and started on hydroxyurea for cytoreduction. His brainstem reflexes were intact, and he was moving the left side spontaneously. Serial CTHs demonstrated expanding hematomas with local mass effect but without midline shift or herniation. In anticipation of potential DS, prophylactic dexamethasone was started. Hours after receiving ATRA, the patient developed a fever of 39.7° C. Shortly after, he suddenly developed bilateral, dilated and fixed pupils and extensor posturing with preserved gag and cough reflexes Repeat CTH showed global cerebral edema resulting in crowding of the basal cisterns. Despite aggressive interventions to reduce the ICP, the patient rapidly progressed to brain death.

Conclusions:

In high risk (WBC >10K) APL patients treated with ATRA, differentiation syndrome causes massive cytokine release from maturing blasts which can precipitate catastrophic global cerebral edema, lead to herniation and death. Although chronic ICP elevations have been reported with ATRA, to our knowledge, this is the first case describing a devastating acute treatment related complication in a patient newly diagnosed with APL.