A case of idiopathic normal pressure hydrocephalus in an elder diabetic patient

The clinical entity idiopathic normal pressure hydrocephalus (iNPH) is characterized by dementia, urinary incontinence, gait ataxia. An 80-year old man with a past history of Type 2 diabetes mellitus admitted to our hospital. Combination of twice Aspart and Aspart premixed30/70 insulin were used. Although, he was unable to inject insulin by himself recently. On physical examination, he walked in a mildly wide based manner. According to his family, urinary incontinence was existed. Laboratory data were as follows: Postrandial blood glucose 243 mg/dl and glycated hemoglobin 8.0% (NGSP). Brain magnetic resonance imaging (MRI) scans showed thinning of the corpus callosum with enlargement of the lateral ventricles on a colonal image. Evan's ratio was 0.29. The revised version of Hasegawa's Dementia scale (HDS-R) was 10. The patient showed no evidence a related antecedent event, such as head trauma, intracerebral hemorrhage and meningitis. Thus, he was diagnosed as having possible Idiopathic normal pressure hydrocephalus (iNPH). The following several psychological tests and walking test were applied. Before and after the tap, he was evaluated using the HDS-R, Mini mental state examination (MMSE), Timed Up and Go test (TUG). Insulin was replaced by glargine, and Sitagliptin was added. On the 31 day, the patient underwent Ventriculo-perioneal shunt. Laboratoly data and memory impairment were also improved. 8 month's later, HbA1c was 7.5%. iNPH occurs in the elderly and is characterized by a clinical triad of gait disturbance, urinary incontinence and dementia. In the present case, thinning of the corpus callosum with enlargement of the lateral ventricles was detected by MRI. 49% of iNPH patients had Diabetes mellitus. However, we were unable to detect a relationship iNPH and Diabetes mellitus. Cognitive impairment may interfere with the insulin therapy. In the present case, failure of insulin self-injection was the first clinical sign to appear. We were able to reduce dose of insulin. We conclude that iNPH is a treatable disorder, especially when treatment is started early in the course of the disease.