Probable ponatinib-induced papilledema in a patient with acute lymphocytic leukemia.

Purpose: Papilledema is a very rare complication of leukemia therapies, and particularly tyrosine kinase inhibitor (TKI) therapy. Targeted oncologic therapies are becoming increasingly popular, so it is increasingly important to report rare adverse effects. We present a case of probable papilledema in the setting of ponatinib therapy for acute lymphoblastic leukemia. Observations: Our patient is a 48-year-old male who was diagnosed with acute lymphocytic leukemia. He underwent stem cell transplantation and shortly after was placed on ponatinib therapy. After initiation of ponatinib, he began to note decreased clarity in the inferonasal visual field of his right eye, corroborated on Humphrey visual field (HVF) testing. Neuroimaging was only notable for a partially empty sella. Lumbar puncture demonstrated opening pressures at the upper limit of normal (23 cm H2O) but with normal cellular constituents and chemistry. Slit lamp exam did not reveal any signs of ocular inflammation. Dilated funduscopic examination (DFE) revealed 360-degree blurring of the right optic disc margin as well as 270-degree blurring of the left optic disc (sparing the temporal border). Optical coherence tomography of the retinal nerve fiber layer (OCT-RNFL) showed increased RNFL thickness of 272 μm in the right eye and 113 μm in the left eye. In the absence of evidence for other possible etiologies of optic disc edema, ponatinib-induced papilledema was suspected. No changes to the ponatinib regimen were made; however, the patient was started on acetazolamide 500 mg twice a day. At three-month follow up, the patient reported resolution of his right eye blurriness and his repeat HVF, OCT-RNFL, and DFE showed resolution of optic disc edema, supporting that his initial bilateral optic disc swelling was likely ponatinib-induced papilledema. Conclusions and importance: This is the first report of probable ponatinib-induced papilledema. This case expands on the literature of TKI induced papilledema and demonstrates successful treatment with an oral acetazolamide regimen.