To elucidate a novel relationship between Cerebellar Hippocampal and Basal Nuclei Transient Edema with Restricted diffusion (CHANTER) syndrome and Pseudobulbar Affect (PBA).

CHANTER syndrome is a rare constellation of radiographic findings on MRI in adults with opioid neurotoxicity¹. It is characterized by symmetrical cytotoxic edema in the hippocampi and cerebellar cortices with a variable distribution in the basal ganglia¹. PBA is a neuropsychiatric disorder that occurs due to brain injury or other neurologic pathology, characterized by uncontrollable outbursts of laughing or crying². To date, there are no cases that describe a connection between CHANTER and PBA.

A 21-year-old female with polysubstance abuse was brought to the emergency room after being found unresponsive. Urine drug screening was positive for fentanyl, cannabinoids, and amphetamines and laboratory studies showed multisystem organ failure. She was intubated and admitted to the ICU. On hospital day 3, MRI revealed bilateral symmetric areas of restricted diffusion involving the caudate deep cerebellar nuclei and hippocampal regions. On day 15, she was extubated but remained nonverbal and did not follow commands reliably. On day 18, MRI showed complete resolution of the previous findings. On day 29, the sudden onset of unpredictable and inappropriate crying and laughter began. Pseudobulbar affect was suspected and sertraline was initiated as  was not available in our facility. In the following days, the patient responded to basic questions and her outbursts of crying and laughter lessened. The patient was discharged to a skilled nursing facility for continuous care.

Pseudobulbar affect may be a novel complication of CHANTER syndrome. Dysregulation of the neural circuits that control emotional lability may arise as a sequela to CHANTER leading to PBA. While both are distinct conditions, clinicians should be aware of a potential link between the two entities.