Reversible tetraplegia due to polyneuropathy in a diabetic patient with hyperosmolar non-ketotic coma

Critical illness polyneuromypathy has not previously been reported as a complication of diabetic coma. We describe a patient with hyperosmolar non-ketotic coma (HONK) complicating gramnegative sepsis in whom persistent coma and profound tetraplegia caused considerable concern. Although, initially, it was feared that the patient had suffered a central neurological complication such as stroke or cerebral oedema, a diagnosis of critical illness motor syndrome (CIMS) was subsequently confirmed neurophysiologically. Profound limb weakness associated with HONK is not necessarily due to a catastrophic cerebral event, rather it may be a result of CIMS, which has an excellent prognosis for full neurological recovery.