Diagnostic Value of Muscle [11C] PIB-PET in Inclusion Body Myositis

• Main Authors: Yu-ichi Noto, Masaki Kondo, Yukiko Tsuji, Shigenori Matsushima, Toshiki Mizuno, Takahiko Tokuda, Masanori Nakagawa
• Format: Article
• Language: English
• Published: Frontiers Media S.A. 2020-01-01
• Series: Frontiers in Neurology
• Subjects: inclusion body myositis; idiopathic inflammatory myopathy; dermatomyositis; polymyositis; amyloid; PIB-PET
• Online Access: https://www.frontiersin.org/article/10.3389/fneur.2019.01386/full

Background: The accumulation of multiple-protein aggregates within muscle fibers is a pathological hallmark of sporadic inclusion body myositis (s-IBM) with the presence of inclusion bodies. Amyloid-beta is one of the accumulated proteins in s-IBM. The aim of this study was to elucidate the utility of Pittsburgh compound B-positron emission tomography (PIB-PET) for diagnosing s-IBM.Methods: Nine patients with s-IBM and four patients with idiopathic inflammatory myopathy (IIM) were included. Patients underwent PIB-PET of body muscles. Standardized uptake values (SUVs) were measured in 16 muscles. A comparison of SUVs was made between s-IBM and IIM groups. The correlation between PIB-PET and clinical parameters was analyzed.Results: The mean SUV of all muscles in s-IBM patients was higher than in IIM patients (0.32 vs. 0.25, respectively; p = 0.031). Subgroup analysis identified a clear difference in SUVs of the forearm and lower-leg muscle groups (p = 0.021 and p = 0.045, respectively). There was no correlation between SUVs and clinical parameters in s-IBM patients.Conclusions: Muscle PIB-PET may help to make a diagnosis of s-IBM.