CHANTER Syndrome: A Rare Cause of Encephalopathy and Ischemic Lesions (P2-5.017)

Abstract

<h3>Objective:</h3> To present a rare case of Cerebellar Hippocampal and Basal Nuclei Transient Edema with Restricted Diffusion (CHANTER) Syndrome. <h3>Background:</h3> CHANTER syndrome is a recently recognized constellation of clinical and radiologic findings. The clinical features include acutely depressed consciousness with obstructive hydrocephalus secondary to cerebellar edema. MRI findings are restricted diffusion in the cerebellar cortex, hippocampi, and basal nuclei. CHANTER is distinguished from ischemic stroke by lack of distribution in a specific vascular territory or vascular occlusion present on angiographic imaging. Etiology may be a primary metabolic or mitochondrial failure of the gray matter with anoxic injury precipitated by opiates or other drugs of abuse. <h3>Design/Methods:</h3> N/A <h3>Results:</h3> A 70-year-old right-handed hypertensive woman with HIV, end-stage renal failure, and lymphoma in remission was in respiratory distress. Seizures of unclear duration were noted on ambulance arrival and midazolam was administered. She was intubated and loaded with levetiracetam for status epilepticus. Norepinephrine was given during a hypotensive episode. Neurological examination was remarkable for lack of motor response to noxious stimuli and present brainstem reflexes consistent with coma. Opiates were detected in urine. MRI brain showed multiple small foci of restricted diffusion involving bilateral cerebellar hemispheres, hippocampi, basal ganglia, and in the right parietal cortex. MR angiography of the head and neck was normal. Video EEGs showed severe diffuse slowing, generalized periodic discharges that became blunted with triphasic morphology after lorazepam and levetiracetam administration. Cardiac monitoring and echocardiogram were unremarkable. Her alertness improved and withdrew minimally all extremities to painful stimuli. She was discharged to a long-term skilled nursing facility. <h3>Conclusions:</h3> This case highlights a rare clinical manifestation suggestive of CHANTER syndrome. Unlike other cases previously described, the cerebellar lesions were not sufficiently large to cause hydrocephalus. However, the clinical recovery was very limited. Status epilepticus and transient hypotension may have played a role in the poor recovery. <b>Disclosure:</b> Dr. Hiana has nothing to disclose. Dr. Soh has nothing to disclose. Dr. Marchidann has stock in Eli Lilly. Dr. Marchidann has stock in Pfizer. Dr. Marchidann has stock in Merck. Dr. Marchidann has stock in Illumina. Dr. Marchidann has stock in Aeterna Zentaris. Dr. Marchidann has stock in Abbot. Dr. Marchidann has received publishing royalties from a publication relating to health care. Dr. Marchidann has received publishing royalties from a publication relating to health care.