Meta-iodobenzylguanidine myocardial scintigraphy in Perry disease.

INTRODUCTION: Perry disease (Perry syndrome), a hereditary TAR DNA-binding protein 43 (TDP-43) proteinopathy, is caused by dynactin subunit 1 (DCNT1) mutations and is characterized by rapidly progressive parkinsonism accompanied by depression, apathy, unexpected weight loss, and respiratory symptoms including central hypoventilation and central sleep apnea. Meta-iodobenzylguanidine (MIBG) myocardial scintigraphy is considered a diagnostic biomarker for Lewy body disease (LBD), as denervation of cardiac sympathetic nerves is a pathological feature in LBD. However, our previous studies have reported a decreased cardiac uptake of MIBG in patients with Perry disease. In this study, we aimed to correlate the MIBG myocardial scintigraphy findings with clinical features in Perry disease. METHODS: We evaluated data obtained from a multicenter survey of patients of Japanese origin with suspected Perry disease, who visited neurology departments in Japan from January 2010 to December 2018. We screened each patient's DNA for the DCTN1 mutation using Sanger sequencing and obtained the clinical details of all patients including findings from their MIBG myocardial scintigraphy. RESULTS: We identified two novel mutations, p.G71V and p.K68E, in DCTN1 in patients from two different families. The majority of patients (7/8, 87.5%) showed a decrease in cardiac uptake (heart to mediastinum ratio) in MIBG myocardial scintigraphy. These patients commonly presented with symptoms related to autonomic dysfunction: constipation, fecal incontinence, urinary disturbance, and orthostatic hypotension. CONCLUSIONS: MIBG myocardial scintigraphy may be a useful biomarker of autonomic dysfunction in Perry disease.