A 62 year old Hispanic male with history of hypertension and type-2 diabetes, presented with a 3-day history of sudden onset, almost constant, irregular, jerk-like, involuntary movements involving his left upper and lower extremities. Movements were absent during sleep and aggravated by purposeful motion. Examination revealed intermittent hemi-choreiform/ballistic movements of the left arm and leg. Initial CT head (CTH) was radiographically reported as “right basal ganglia hemorrhagic infarct” due to hyperdensity in that region. Further review of CTH scan pointed towards metabolic deposition leading to ill-defined, faint, hyperdensity in the right basal ganglia rather than a haemorrhage. Laboratory findings included hyperglycemia (Glucose level of 499), elevated HbA1c (14.5%), and elevated CPK (581). MRI brain demonstrated hyperintensity within the right putamen on T1, with no abnormal signal seen on diffusion weighted or gradient echo sequences to indicated ischemic or hemorrhagic lesions. MR angiogram of the head and neck was normal. Treatment included initiating subcutaneous insulin, clonazepam  and risperidone, resulting in some improvement of the involuntary movements which reintensified on outpatient follow up probably due to insulin noncompliance. Subsequently, patient was started on valbenazine and with reinforcement of his glycemic control, resulted in evident amelioration of his symptoms thereafter.

NKHHH is a great mimicker of an acute vascular event. Although this entity is a diagnosis of exclusion, entertaining the possibility of its occurrence while evaluating a patient in the acute setting is crucial. This will help minimize initial misdiagnosis as treatment modalities differ. Continued emphasis on primary prevention is key.