Supplementary Material for: Diabetic striatopathy (hyperglycemic hemichorea-hemiballismus syndrome) in a young patient with type 1 diabetes mellitus in Dar es Salaam, Tanzania: a case report

Introduction:
Diabetic striatopathy, or nonketotic hyperglycemic hemichorea-hemiballismus syndrome, is a rare movement disorder linked to poorly controlled diabetes mellitus. It predominantly affects older women with type 2 diabetes mellitus and presents with characteristic basal ganglia abnormalities on CT and MRI. Even rarer is the presentation in a young patient, which may pose diagnostic and management challenges.

Case Presentation:
We report a 17-year-old male with poorly controlled type 1 diabetes mellitus presenting with left-sided hemichorea-hemiballismus of acute onset associated with hyperglycemia without ketoacidosis. Brain imaging revealed increased attenuation in the right caudate and putamen on CT and hyperintensity on T1-weighted MRI, consistent with diabetic striatopathy. The abnormal movements abated after one month through dietary counseling, increased insulin dosage, and anti-chorea therapy.

Conclusion:
Diabetic striatopathy may occur in young patients with type 1 diabetes mellitus. In resource-limited settings, its management can be challenging. There is a need for increased awareness among physicians of this potentially reversible condition, especially when seeing atypical patient populations. Strict glycemic control is an essential part of treatment.