BEVACIZUMAB-INDUCED ATYPICAL ENCEPHALOPATHY

Abstract

SESSION TITLE: Medical Student/Resident Pharmacotherapeutics SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/09/2018 01:15 PM - 02:15 PM INTRODUCTION: Posterior reversible encephalopathy syndrome (PRES) manifests as edema in the white matter of the posterior regions of the cerebral hemispheres. PRES has been mostly associated with acute hypertensive encephalopathy along with variety of other causes. We are presenting a case of unusual PRES CASE PRESENTATION: A 43-year-old man with a past medical history of grade III anaplastic astrocytoma of the brainstem presented to the emergency department due to acute changes in mental status and fever. Seven months prior to presentation, bevacizumab (Avastin) was started. On admission BP of 203/124 mmHg, HR of 139/min and temperature of 103°F were found. The patient’s Glasgow coma scale was 10. His complete blood count and complete metabolic panel were unremarkable. Procalcitonin was elevated at 2.46 ng/mL. CT head without contrast indicated evidence of old tumor but no hemorrhage or mass effect. CSF showed mild elevation of protein but no cells. Magnetic resonance imaging of the brain exhibited signal abnormalities in the cerebellum and occipital lobes compatible with PRES. There was no evidence of infection by microbiological data. Once the patient’s hypertension was controlled, his mental status quickly improved and he had a full recovery after rehabilitation. DISCUSSION: Bevacizumab (Avastin) is a recombinant humanized monoclonal antibody that binds to vascular endothelial growth factor (VEGF) to prevent association with endothelial receptors. Bevacizumab (Avastin) inhibits angiogenesis and microvascular growth to subsequently slow down the growth of all tissues, including malignant tissues. The incidence of hypertension with bevacizumab (Avastin) therapy is estimated range from 8 to 67%. PRES has been reported with an incidence of <0.5% in clinical studies and the onset was anywhere from 16 hours to 1 year of initiation of Bevacizumab therapy.[1] A literature review from 2015 reported 21 cases of bevacizumab-induced PRES, 20 of which had complete recovery following withdrawal of medication along with strict BP control.[2] The concomitant occurrence of fever and PRES in the absence of infection has been identified in previous case reports,[3] however, fever along with elevated procalcitonin in the setting of PRES, without any evidence of bacterial infection, has never been documented. CONCLUSIONS: Hypertension and PRES are potential adverse effects of Bevacizumab therapy. Patients taking Bevacizumab require strict monitoring and control of their blood pressure. Although the combination of fever, altered mental status and elevated procalcitonin should alert physicians to infectious process potentially in the central nervous system, PRES should not be missed especially in patients receiving Bevacizumab. Reference #1: Product Information: AVASTIN(R) intravenous injection, bevacizumab intravenous injection. Genentech Inc (per manufacturer), South San Francisco, CA, 2016. Reference #2: Eryılmaz MK, Mutlu H, Salim DK, Musri FY, Coşkun HŞ. Fatal posterior reversible leukoencephalopathy syndrome associated coma induced by bevacizumab in metastatic colorectal cancer and review of literature. J Oncol Pharm Pract. 2016;22(6):806-810. Reference #3: Xie C, Jones VT. Reversible posterior leukoencephalopathy syndrome following combinatorial cisplatin and pemetrexed therapy for lung cancer in a normotensive patient: A case report and literature review. Oncol Lett. 2016;11(2):1512-1516. DISCLOSURES: No relevant relationships by Bhavinkumar Dalal, source=Web Response No relevant relationships by Ahmad Said, source=Web Response