Office-based respiratory assessment in patients with generalized myasthenia gravis.

Patients with myasthenia gravis (MG) can present with respiratory dysfunction, ranging from exercise intolerance to overt respiratory failure, increased fatigue, or sleep-disordered breathing. To investigate the value of multiple respiratory tests in MG, we performed clinical and respiratory assessments in patients with mild to moderate generalized disease. One-hundred and thirty-six patients completed the myasthenia gravis quality-of-life score(MG-QOL-15), myasthenia gravis impairment index(MGII), Epworth sleepiness scale(ESS), University of California-San Diego Shortness of Breath Questionnaire(UCSD-SOB), Modified Medical Research Council Dyspnea Scales(MRC-DS), supine and upright forced vital capacity(FVC), maximal inspiratory pressures(MIPs) and sniff nasal inspiratory pressures(SNIP). Seventy-three (54 %) had respiratory and/or bulbar symptoms and 45 (33 %) had baseline abnormal FVC, with no significant postural changes (p = 0.89); 55 (40.4 %) had abnormal MIPs and 50 (37 %) had abnormal SNIPs. Overall, there were low scores on respiratory and disability scales. Females had increased odds of presenting with abnormal FVC (OR 2.89, p = 0.01) and MIPs (OR 2.48, p = 0.022). There were significant correlations between MIPs, FVC and SNIPs; between MGII/MG-QOL15 and UCSD-SOB/MRC-DS and between ESS and respiratory scales in the whole group. Our data suggests that office-based respiratory measurements are a useful screening method for stable MG patients, even when presenting with minimal respiratory symptoms and no significant disability.

Value of multi-modality small fiber assessments in a genotypically diverse cohort of transthyretin-related amyloidosis in the early stages of disease.

INTRODUCTION: Transthyretin-related amyloidosis (ATTRv) is a progressive multisystem disorder, predominantly involving the peripheral nerve system (PNS) and heart. Quantification of small fiber damage may help guide treatment decisions, as amyloid deposits frequently affect those fibers early in disease course. Corneal confocal microscopy (CCM) is a promising method to monitor patients with ATTRv, due to similarities between corneal nerves and PNS, as the cornea is innervated by Aδ and C fibers. METHODS: We compared CCM measures from ATTRv patients to a group of healthy individuals, matched by age and gender. We then investigated the correlations between small fiber tests (SFT): CCM, LDI-Flare and CDT, COMPASS-31 and disability scales (RODS and ONLS) in patients. RESULTS: Of 20 patients (6 with V30M), mean age 50.3±15.3Y, 7 female (35%), six (30%) had polyneuropathy and 10 (50%) carpal tunnel syndrome. CDT was abnormal in 9 and LDI-flare in 6 patients. CCM was abnormal in 19 tested patients and significantly reduced when compared to controls (CNFL: 6.31±0.31 vs. 15.21±1.02mm/mm2, p<0.001). Mean COMPASS-31-scores were 22.27±22.84; RODS and ONLS were 38.15±12.33 and 2.05±2.3, with no significant differences between sub-group scores. Disease duration was significantly correlated with ONLS (0.43, p=0.05) and RODS (0.46, p=0.03). There were no significant correlations between measures of disability and SFT. CONCLUSIONS: In a diverse cohort of ATTRv patients, CCM was the most frequent abnormal measurement. CCM can be a useful test to triage patients in the early disease stages and with few or equivocal symptoms.

Epilepsy in neurofibromatosis type 1: Prevalence, phenotype, and genotype in adults.

PURPOSE: Studies have shown an increased risk of epilepsy in patients with neurofibromatosis type 1 (NF1). However, most reports focus on the pediatric population. In this study, we describe the trajectory of patients with NF1 and epilepsy beyond childhood. METHODS: Patients with NF1 ≥18 years-old consecutively seen at a multidisciplinary neurofibromatosis clinic during a four-year period were prospectively enrolled and offered routine EEG, MRI, and genetic testing. The lifelong and point prevalence of epilepsy in patients with NF1 were calculated. Demographic, genetic, radiological, and clinical features found to be statistically associated with having received a diagnosis of epilepsy were incorporated into a logistic regression model. RESULTS: Among 113 patients with NF1 included in this study (median age at study inclusion: 33 years), the lifelong prevalence of epilepsy was 11% (CI95%=6-18%) and point prevalence 7% (CI95%= 3-13%). Most patients (73%) were diagnosed with epilepsy before the age of 18 and achieved seizure-freedom by adulthood. At study inclusion, three-quarters of patients with a diagnosis of epilepsy had been seizure-free for more than one year and a third had resolved epilepsy. A routine EEG with epileptiform discharges had a sensitivity of 25% (CI95%=3-65) and specificity of 99% (CI95%=93-100) for identifying adult patients with NF1 and unresolved epilepsy. A history of epilepsy was associated with having a low-grade glioma (OR: 38.2; CI95%=2.2-674.7; p<0.01), learning disability (OR: 5.7; CI95%=1.0-31.5; p<0.05), and no plexiform neurofibroma (OR: 0.05; CI95%=0.0-0.8; p=0.04). No single mutation type was associated with the development of epilepsy. CONCLUSIONS: In patients with NF1, although resolution of epilepsy over time was observed in many cases, the prevalence of epilepsy was higher among adults with NF1 than that reported in the general population. Epileptogenesis in NF1 likely requires the combination of multiple genetic and environmental factors and suggests involvement of a network that spreads beyond the borders of a well-defined parenchymal lesion.

Efficacy and safety of high infusion rate IVIG in CIDP.

BACKGROUND: We aimed to determine the safety and tolerance of higher rates of infusion of intravenous immunoglobulin (IVIG) in patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). METHODS: Patients began infusions with 10% IVIG at the standard rate of 0.08 mL/kg/min. If tolerated, infusion rates were incrementally increased to 0.14 mL/kg/min. We considered the frequency of infusions with adverse events (AEs) as the primary outcome. RESULTS: Nineteen of 25 patients safely tolerated the maximum rate of 0.14 mL/kg/min. We observed 25 treatment-related AEs (TAEs) over 13 infusions at standard or transitional rates, across seven patients. We observed no TAEs associated with the maximum infusion rate. CONCLUSIONS: We found that 10% IVIG can be safely administered at a high infusion rate (0.14 ml/kg/min) in most CIDP patients, reducing the treatment time and burden on healthcare resources.

Prospective study of stress, depression and personality in myasthenia gravis relapses.

BACKGROUND: Psychopathology and personality traits may influence the course of autoimmune disorders. With this prospective longitudinal cohort study, we aimed to assess personality, stress and depression in myasthenia patients who relapse and those who remain stable or improve (non-relapsers). METHOD: We collected data from 155 consecutive adult patients with confirmed MG attending the Neuromuscular Clinic, Toronto General Hospital, between March 2017 and July 2018, for this study. Patients were assessed at baseline and 6 months, or at the time of MG relapse. At both visits, the patients were assessed clinically and were asked to complete self-administered questionnaires for disease severity, chronic stress and depression. Personality type was assessed at baseline only. Relapsing patients were defined as those patients with MGII score increasing by more than 5.5 points from visit 1 to visit 2. RESULTS: Relapsers had higher baseline scores for depression (p = 0.01) and the change in disease severity correlated with the change in depression score (r = 0.2534, p = 0.0015, 95% CI: 0.098 0.3961). Higher levels of stress at baseline and neuroticism predicted higher relapse rates (p = 0.01 and p < .0001, respectively). In the linear regression model, with change of the MGII score as the dependent variable, change in depression scores (p = 0.0004) and age (p = 0.03) predicted change in disease severity. CONCLUSIONS: Since emotional factors and personality type may influence MG, attention to these factors might improve care in MG patients.