Case Presentation: A 79 year-old female with a history of congestive heart failure (CHF) and poorly controlled type two diabetes mellitus (T2DM) presented from sub-acute rehab (SAR) with shortness of breath and bilateral lower extremity edema. In the ED, her vitals were stable except for mild hypoxia requiring 2L of oxygen. Labs revealed elevated B-type natriuretic protein to 218 and a glucose of 344 without evidence of ketosis. Physical exam demonstrated an obese woman with signs of hypervolemia and involuntary large amplitude irregular movements of the left-sided extremities. She was admitted for presumed CHF exacerbation. Choreiform movements were, notably, absent during a primary care visit 3 months prior. In-depth chart review revealed 1-2 months of involuntary movements without associated weakness or sensory deficits. The first documentation of these movements was in one of two recent hospitalizations for CHF, prompting evaluation of a possible movement disorder. During the first hospitalization, a non-contrast head CT revealed a hyperdensity of the right lentiform nucleus with relative sparing of the internal capsule, described by radiology as either artifact or related to non-ketotic hyperglycemia. The movements improved and CT findings were presumed to be artifact. During her second hospitalization, repetitive movements of the left arm were again noted, but further workup was deferred given recent, largely unremarkable, imaging. By the third hospitalization, the patient had constant involuntary movements of her left upper and lower extremities. Neurology was consulted and raised suspicion for nonketotic hyperglycemic hemichorea (NKH-HC), as most recent hemoglobin A1c was >14%. Following diuresis, the patient was discharged to SAR with plan for short-interval neurology follow-up, improved glycemic control, and possible initiation of risperidone if symptoms persisted.
Discussion: NKH-HC is characterized by glucose levels greater than 200 mg/dL, often in the setting of poorly controlled DM, and acute choreiform movements of the extremities. Lesions can be identified on CT or MRI brain and are typically in the lentiform nucleus of the basal ganglia. Over the past forty years, there have been several case reports documenting NKC-HC. Our case adds to the growing body of literature describing this rare condition. Despite imaging findings suggestive of NKH-HC during the first hospitalization, our patient did not receive a formal diagnosis until her third hospitalization. Acute choreiform movements are often the presenting symptom, but were an incidental finding in our patient. It is likely that slowly worsening glycemic control led to the progression of her choreic movements between hospitalizations. As rates of T2DM increase, rare complications such as NKH-HC will become more common. Hospitalists are well-poised to diagnose and treat NKC-HC given their experience with more common hyperglycemic emergencies, such as diabetic ketoacidosis and hyperglycemic hyperosmolar state. Treatment for NKH-HC is tight glycemic control with insulin. The addition of dopamine receptor antagonists, such as risperidone, can be considered if symptoms persist.
Conclusions: Hospitalists frequently care for patients with hyperglycemic emergencies. Although rare, NKH-HC is a documented complication of poorly controlled DM. Diagnosis is easily confirmed with CT or MRI brain. It is often reversible with tight glycemic control. Early recognition and treatment is essential for the best chance at full motor recovery.