Pinto, Marcus Vinícius

AbstractHereditary transthyretin amyloidosis with peripheral neuropathy (ATTRv-PN) is an autosomal dominant inherited sensorimotor and autonomic polyneuropathy with over 130 pathogenic variants identified in the TTR gene. Hereditary transthyretin amyloidosis with peripheral neuropathy is a disabling, progressive and life-threatening genetic condition that leads to death in ∼ 10 years if untreated. The prospects for ATTRv-PN have changed in the last decades, as it has become a treatable neuropathy. In addition to liver transplantation, initiated in 1990, there are now at least 3 drugs approved in many countries, including Brazil, and many more are being developed. The first Brazilian consensus on ATTRv-PN was held in the city of Fortaleza, Brazil, in June 2017. Given the new advances in the area over the last 5 years, the Peripheral Neuropathy Scientific Department of the Brazilian Academy of Neurology organized a second edition of the consensus. Each panelist was responsible for reviewing the literature and updating a section of the previous paper. Thereafter, the 18 panelists got together virtually after careful review of the draft, discussed each section of the text, and reached a consensus for the final version of the manuscript.

See article on pages 111‐116 in this issue.

AbstractIntroductions/AimsInclusion body myositis (IBM) typically presents with progressive weakness preferentially involving finger flexors and quadriceps. Atypical presentations have been less commonly reported. Here, we aim to describe the clinical characteristics and long‐term outcomes of IBM patients with atypical presentations.MethodsWe retrospectively searched the Mayo Clinic medical records to identify IBM patients with atypical disease onset, seen between 2015 and 2020.ResultsWe identified 357 IBM patients, of whom 50 (14%) had an atypical presentation. Thirty‐eight patients were diagnosed with IBM because they fulfilled one of the European Neuromuscular Center diagnostic categories at a later stage, 10 had all IBM histopathological features, and 2 were diagnosed on the basis of clinical and laboratory data. The most common presentation was dysphagia (50%), followed by asymptomatic hyperCKemia (24%; CK, creatine kinase), then foot drop (12%). 6% of patients presented with proximal arm weakness, 4% with axial weakness and 4% with facial diplegia. Median time from symptom onset to diagnosis was 9 y. Median age at diagnosis was 70.5 y. 16% of patients needed a walking aid. When tested, 86.5% of patients had impaired swallowing and 56% had elevated cytosolic nucleotidase‐1A antibodies. Only 1/26 patients who received immunotherapy had minimal improvement. Upon follow‐up, most patients had generalization of their weakness with a decline in their strength summated score of 0.082/mo.DiscussionA significant proportion of IBM patients may have an atypical presentation. Recognition of such heterogeneity could improve early diagnosis, prevent unnecessary immunotherapy, and provide insight for future diagnostic criteria development and clinical trials.

AbstractIntroduction/AimsRecently, our group found an association between diabetes mellitus (DM) and lumbosacral radiculoplexus neuropathy (LRPN) in Olmsted County, Minnesota; we found a higher risk (odds ratio [OR], 7.91) for developing LRPN in diabetic compared with nondiabetic patients. However, the influence of other comorbidities and anthropomorphic variables was not studied.MethodsDemographic and clinical data from 59 LRPN patients and 177 age/sex‐matched controls were extracted using the Rochester LRPN epidemiological study. Differences between groups were compared by chi‐square/Fisher exact test or Wilcoxon rank‐sum test. Uni‐ and multivariate logistic regression analysis were performed.ResultsFactors predictive of LRPN on univariate analysis were DM (OR, 7.91; 95% confidence interval [CI], 4.11‐15.21), dementia (OR, 6.36; 95% CI, 1.13‐35.67), stroke (OR, 3.81; 95% CI, 1.32‐11.01), dyslipidemia (OR, 2.844; 95% CI, 1.53‐5.27), comorbid autoimmune disorders (OR, 2.72; 95% CI, 1.07‐6.93), hypertension (OR, 2.25; 95% CI, 1.2‐4.13), obesity (OR, 2.05; 95% CI, 1.11–3.8), body mass index (BMI) (OR, 1.1; 95% CI, 1.04‐1.15), and weight (OR, 1.02; 95% CI, 1.009‐1.037). On multivariate logistic regression analysis only DM (OR, 8.03; 95% CI, 3.86‐16.7), comorbid autoimmune disorders (OR, 4.58; 95% CI, 1.45‐14.7), stroke (OR, 4.13; 95% CI, 1.2‐14.25), and BMI (OR, 1.07; 95% CI, 1.01‐1.13) were risk factors for LRPN.DiscussionDM is the strongest risk factor for the development of LRPN, followed by comorbid autoimmune disorders, stroke, and higher BMI. Altered metabolism and immune dysfunction seem to be the most influential factors in the development of LRPN.

Abstract Objective To determine whether histopathological, electromyographic and laboratory markers correlate with clinical measures in inclusion body myositis (IBM). Methods We reviewed our electronic medical records to identify patients with IBM according to European Neuromuscular Center (ENMC) 2011 criteria, seen between 2015 and 2020. We only included patients who had a muscle biopsy and needle electromyography (EMG) performed on the same muscle (opposite or same side). We used a detailed grading system [0 (normal) to 4 (severe)] to score histopathological and EMG findings. Clinical severity was assessed by the modified Rankin scale (mRS), muscle strength sum score (SSS), quadriceps strength and severity of dysphagia on swallow evaluation. Serum markers of interest were creatine kinase level and cN-1A antibodies. Results We included 50 IBM patients, with a median age of 69 years; 64% were males. Median disease duration at diagnosis was 51 months. On muscle biopsy, endomysial inflammation mainly correlated with dysphagia, and inversely correlated with mRS. Vacuoles and congophilic inclusions did not correlate with any of the clinical measures. On EMG, the shortness of motor un it potential (MUP) duration correlated with all clinical measures. Myotonic discharges, and not fibrillation potentials, correlated with the severity of inflammation. Serum markers did not have a statistically significant correlation with any of the clinical measures. Conclusions Dysphagia was the main clinical feature of IBM correlating with endomysial inflammation. Otherwise, inclusion body myositis clinical measures had limited correlation with histopathological features in this study. The shortness of MUP duration correlated with all clinical measures.