SAT-473 Acromegaly and Drug-Induced Parkinsonism Were Controlled by Lanreotide

BACKGROUND Serum IGF-1 is reported as possible marker for risk and early diagnosis of Parkinson's disease in Neurology. Acromegaly is a disease that causes organ symptoms as a result of the high level of IGF-1. Despite the elevation of IGF-1 in acromegaly patients, there is little report on Parkinson's syndrome of acromegaly. A clinical course of acromegaly with co-morbidity of diabetes mellitus and depression suggested a possible relationship between IGF-1 transition and drug-induced Parkinsonism. CASE A 55-year-old woman with co-morbidity of diabetes mellitus and depression was diagnosed as acromegaly. Her HbA1C was 14.4% because of untreated diabetes. Her GH was elevated to 777 ng/mL and MRI indicated macroadenoma of pituitary gland. Contrary to GH elevation, her IGF-1 was in the normal range of 103 ng/mL (normal range: 75-210 ng/mL), that was a false negative result due to untreated diabetes. The continuation of insulin therapy produced a gradual rise in IGF-1 as a result of glycemic control. Antidepressants were continued by psychiatrists. Three months after starting insulin treatment, her IGF-1 increased to 305 ng/mL . From then on, her coarse tremor was observed and she was not capable to write letters at all. (111)In-pentetreotide scintigraphy (Octreoscan) showed radiotracer accumulation in her pituitary gland, excluding the existence of ectopic GHRH-producing tumors. For the treatment of pituitary tumor and Parkinsonism, bromocriptine was tried but stopped because of liver dysfunction. After checking the safety and response of octreotide, monthly injection of lanreotide was started. Fourteen months after starting lanreotide, her IGF-1 was decreased to 71 ng/mL and her coarse tremor disappeared. She also became capable of writing and self-monitoring of blood glucose for diabetes. Disappearance of her tremor improved her activity of daily life. A woman with acromegaly with comorbidity of depression and diabetes was treated. An elevation of IGF-1 produced coarse tremor and lowering of IGF-1 improved the symptom. Lanreotide controlled drug-induced Parkinsonism by lowering IGF-1 level. CLINICAL LESSONS This clinical course and transition of IGF-1 suggested the involvement of IGF-1 in parkinsonism. There has been no report of drug-induced Parkinsonism with comorbidity of acromegaly of which IGF-1 and symptoms were observed chronologically. This case suggested a possibility that an elevation of IGF-1 lowers the threshold of drug-induced Parkinsonism.