Long-Term Remission With Low-Dose Rituximab in Myasthenia Gravis: A Retrospective Study.

OBJETIVE: Rituximab (RTX) is a therapeutic option, for patients with myasthenia gravis (MG) not responding to conventional immunosuppressive treatment. In this cohort, we evaluated long-term efficacy of RTX in the treatment of refractory generalized MG. METHODS: A retrospective study was performed in adult patients with refractory generalized MG and at least 24 months of follow-up, between January/2015 and October/2021. The Myasthenia Gravis Status and Treatment Intensity Score was used to assess outcomes, and CD19/CD20+ B-cell counts were monitored. RESULTS: Sixteen patients with MG (8 antiacetylcholine receptor+ and 8 muscle-specific antikinase+; mean age 45.5 ± 16.2 years) treated with low-dose RTX protocols were included. CD19/CD20 levels remained undetectable 12 months after induction, and no new relapses were observed during follow-up. CONCLUSIONS: Low-dose RTX infusions were sufficient to achieve undetectable CD19/20 cell counts and sustained clinical remission. In low and middle-income countries, the impact of low-dose RTX therapy represents a paradigm shift in decision-making for long-term treatment.

Childhood focal compressive mononeuropathies during the COVID-19 pandemic in Buenos Aires, Argentina.

INTRODUCTION/AIMS: Focal peripheral neuropathies are infrequently seen in pediatric patients. The COVID-19 pandemic has disrupted normal life for many people, including complete lockdowns and school closing for long periods of time in many countries, which prompted children to stay at home. Our aim is to assess whether there has been an increased incidence of focal compressive peripheral neuropathies in the pediatric population during COVID-19-associated lockdown. METHODS: Clinical, electrophysiological, and imaging characteristics were reviewed for patients referred to the electrodiagnostic (EDx) laboratory with suspicion of a focal neuropathy. The incidence of focal compressive peripheral neuropathies seen during the period of March to September 2020 was compared with the same time period in 2019. RESULTS: An increased incidence of focal neuropathies was seen in 2020 (31%) compared with 2019 (6.8%). During 2020, 7 fibular (peroneal) mononeuropathies and 2 ulnar neuropathies were diagnosed. Most patients with focal neuropathies were underweight and acknowledged prolonged screen time periods. Electrophysiological findings consisted of mostly demyelinating lesions with an overall good clinical outcome. DISCUSSION: In this study we raise awareness about a possible increased incidence of focal compressive peripheral neuropathies in children during COVID-19-associated lockdown, which may be prevented with changing positions during sedentary activities.

Re-emergent tremor provocation.

INTRODUCTION: Rest and re-emergent tremor (RET) in Parkinson's disease (PD) are known to be markedly variable. The aim of this study is to evaluate the effect of tremor provocation on RET latency and variability. METHODS: We performed a prospective observational study in 21 PD patients with RET. Evaluations were conducted by accelerometric analysis of hand movements with and without provocation by counting out loud backwards from 100, in the OFF state. Differences in RET pause duration, tremor power at peak frequency, root mean square (RMS) and slope of return of the tremor after the pause was measured. Inter- and intra-subject variability were also calculated. RESULTS: RET pause duration showed a 75% decrease after provocation (p < 0.001), which led to zero in 52% of cases, as compared to 9% in unprovoked measurements (p < 0.001). Provocation also led to a 2.57 time increase in tremor power (p < 0.001), 1.37 time increase in RMS (p < 0.001) and 2.47 time increase in slope (p < 0.001). A significant decrease in inter-subject variability was also observed (p = 0.001). CONCLUSION: Tremor provocation led to RET amplitude increase, pause shortening, and variability decrease. Therefore, while provocation can be recommended for the evaluation of rest tremor in clinical practice, it might well annul its value for identifying the pause prior to re-emergent tremor.

Latency of re-emergent tremor in Parkinson's disease is influenced by levodopa.

INTRODUCTION: Re-emergent tremor (RET) is a common form of postural tremor observed in Parkinson's disease (PD) patients. Recent studies have shown that administration of levodopa decreases RET amplitude. However, drug effects on tremor pause duration are less clear. METHODS: We performed a prospective observational study in PD patients with RET, subjected to acute levodopa challenge. Tremor activity was measured during OFF and ON states both clinically, as well as by using accelerometers taped to the back of both hands. Correlation between RET amplitude and pause duration, as well with MDS-UPDRS scores were investigated. The slope of gradual increase of postural tremor after the pause was also measured in the OFF and ON states. RESULTS: Significant inverse correlation between tremor amplitude and RET pause duration was observed in OFF (rs = -0.474, p = 0.030) and ON (rs = -0.569, p = 0.006) states. Levodopa reduced tremor amplitude (26%, p = 0.004) dampening slope gradient (22%, p = 0.029). Tremor pause duration also showed inverse correlation with postural tremor amplitude measured by MDS-UPDRS in OFF (rs = -0.311, p = 0.048) and ON (rs = -0.503, p = 0.020) states, as well as with total MDS-UPDRS Part III score (rs = -0.295, p = 0.009). Finally, accelerometric analysis proved to be more sensitive than visual inspection for detecting tremor pauses. CONCLUSION: Our results suggest RET pause duration is amplitude related, since levodopa-induced amplitude decrease led to pause prolongation, associated with decreased tremor intensity and slope gradient dampening.