Diabetic striatopathy (DS) is an uncommon cause of dyskinesias, such as chorea-ballismus, associated striatal T1 hyperintensity on MRI brain. Commonly described in hyperglycemic hyperosmolar state (HHS), it is rarely reported in diabetic ketoacidosis (DKA). We present a case in which not only did the patient develop DKA related DS, but developed hemiparesis instead of dyskinesias.

A 50-year-old man with history of type II diabetes mellitus and prior right putamen hemorrhage with minimal residual left sided weakness presented with increased left arm and leg weakness in the setting of DKA. CT head showed hyperdensity in right corpus striatum, initially thought to be hemorrhage. MRI brain revealed T1 hyperintensity in the entire right corpus striatum with susceptibility weighted imaging signal dropout only in right putamen, indicating prior hemorrhage. Review of prior CT scans from 2014 and 2015 revealed developing striatal hyperdensity, though the clinical manifestations only appeared after development of DKA. After resolution of DKA, his weakness improved slowly during the course of hospitalization, though the imaging abnormality persisted at a two monthly follow-up MRI brain.

Radiologic lesions of DS have been attributed to gemistocyte accumulation and neuronal loss while biopsies have demonstrated hyaline degeneration, arteriolar thickening and vascular proliferation. GABA depletion in HHS has been hypothesized to cause the dyskinesias, though this is less applicable to DKA since GABA is made by liver produced acetoacetate. Again, this does not explain the localized weakness observed in some cases. Patient’s HbA_1c trended upwards from 6.8 in 2014 to 17.7 in 2018. This corresponded with progression of CT findings over that time period.

DS is an uncommon condition that clinicians need to be aware of as CT head findings can easily be mistaken for hemorrhage, while clinical manifestations of this condition are reversible in >90% of patients with prompt treatment of metabolic derangements.