Hyunjin Kim1, Young-Min Lim1, Joo Yea Jin1, Dok Hyun Yoon2, Cheolwon Suh2, Sun-Young Kim3, Jae-Cheol Jo4, Kwang-Kuk Kim1. 1. Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. 2. Department of Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. 3. Department of Neurology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea. 4. Department of Hematology and Oncology, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Republic of Korea.
Abstract
INTRODUCTION: Polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome and monoclonal gammopathy of undetermined significance (MGUS) are paraproteinemic disorders that can cause demyelinating polyneuropathy. Herein we assessed the findings of nerve conduction studies (NCS) in patients with POEMS syndrome and MGUS-related neuropathy to determine whether the NCS characteristics can help differentiate between these conditions. METHODS: We enrolled 24 POEMS and 37 MGUS-related neuropathy patients. NCS parameters, including compound muscle action potential (CMAP), motor conduction velocity (MCV), and terminal latency index (TLI), were evaluated. RESULTS: Compared with MGUS-related neuropathy patients, POEMS syndrome patients demonstrated a greater reduction in both the upper and lower limb CMAPs and a greater reduction in the median and ulnar MCVs. The TLIs were significantly higher in POEMS patients. DISCUSSION: NCS can help distinguish POEMS syndrome from MGUS-related neuropathy. Reduced CMAPs, slow MCVs, and high TLIs are indicative of POEMS syndrome rather than MGUS-related neuropathy. Muscle Nerve 56: E73-E77, 2017.
INTRODUCTION:Polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes (POEMS) syndrome and monoclonal gammopathy of undetermined significance (MGUS) are paraproteinemic disorders that can cause demyelinating polyneuropathy. Herein we assessed the findings of nerve conduction studies (NCS) in patients with POEMS syndrome and MGUS-related neuropathy to determine whether the NCS characteristics can help differentiate between these conditions. METHODS: We enrolled 24 POEMS and 37 MGUS-related neuropathypatients. NCS parameters, including compound muscle action potential (CMAP), motor conduction velocity (MCV), and terminal latency index (TLI), were evaluated. RESULTS: Compared with MGUS-related neuropathypatients, POEMS syndromepatients demonstrated a greater reduction in both the upper and lower limb CMAPs and a greater reduction in the median and ulnar MCVs. The TLIs were significantly higher in POEMS patients. DISCUSSION: NCS can help distinguish POEMS syndrome from MGUS-related neuropathy. Reduced CMAPs, slow MCVs, and high TLIs are indicative of POEMS syndrome rather than MGUS-related neuropathy. Muscle Nerve 56: E73-E77, 2017.