Background and Objectives: Ravulizumab, a long-acting C5 complement inhibitor, was approved in the US and Europe in 2022 as an add-on therapy for the standard treatment of AChR-positive generalized MG (gMG). We share our real-world experience with adult patients receiving this therapy in Romania. Materials and Methods: Six AChR-positive gMG patients received ravulizumab through an Early Access Program (January 2023–October 2024). Patient outcomes were assessed at the therapy start and q8w using Quantitative MG (QMG), MG Activities of Daily Living (MG-ADL), and MG Quality of Life 15-item revised (MG-QoL15r) scales. Results: Age at disease onset ranged from 15 to 35 years. Four of the six patients were women. Two patients had gMG severity level of IIa, and four patients of IIb according to the Myasthenia Gravis Foundation of America (MGFA) classification. Five patients experienced rapid and sustained improvements in MG symptoms with MG-ADL score reductions ranged from −3 to −5 at 26 weeks post-ravulizumab start (except for those with a low baseline score: three and one). QMG score dropped in three patients (−2 to 12) during the treatment period, increased in two (+2 and +8), and remained stable in one (zero). Three patients showed sustained improvement in MG symptoms after ≥60 weeks. MG-QoL15r significantly dropped (−22 to −10) throughout the treatment period. One patient experienced ravulizumab-associated adverse events (vomiting, diarrhea, chills) that resolved within 24 h following symptomatic management, two to three episodes of myasthenic exacerbations during treatment, and discontinued it. Conclusions: All cases presented here had early-onset AChR antibody-positive, non-thymomatous MG. Despite differences in disease duration and underlying conditions, clinically meaningful and sustained improvements in gMG symptoms, and reduced corticosteroid doses were observed in all patients except one after adding ravulizumab to the treatment plan.

Background: Bisphosphonate scintigraphy (BS) is a recognized tool for diagnosing amyloid transthyretin cardiomyopathy (ATTR-CA). However, its sensitivity for rare transthyretin (TTR) variants, like Glu54Gln, remains underexplored. Methods: This was a retrospective descriptive study including all known patients with the Glu54Gln variant diagnosed between 2017 and 2023 in Romania, aiming to evaluate the diagnostic performance of BS in Glu54Gln ATTR–CA. Results: All symptomatic patients (n = 22) with histologically confirmed ATTR-CA had positive BS results (100% sensitivity). No false negatives were observed in asymptomatic carriers (n = 4). The Perugini visual score correlated with disease severity, with grade 3 scores associated with advanced cardiac involvement. We proposed a new parameter, heart-to-liver-uptake (H/L) ratio, which proved a strong positive correlation with both the heart-to-contralateral-uptake (H/CL) ratio (R² = 0.768, p < 0.001) and interventricular septum thickness (R² = 0.584, p < 0.001) and a weak correlation with the global longitudinal strain (R² = 0.212, p = 0.023). Conclusions: BS demonstrates high diagnostic accuracy for Glu54GlnATTR-CA, underscoring its utility in early diagnosis and clinical management. The H/L ratio presents a novel approach to semiquantitative analysis of bisphosphonate uptake in cardiac amyloidosis, potentially addressing key limitations of the traditional H/CL ratio.

Background and Objectives: Amyloidosis is a disorder characterized by the abnormal folding of proteins, forming insoluble fibrils that accumulate in tissues and organs. This accumulation disrupts normal tissue architecture and organ function, often with serious consequences, including death if left untreated. Light-chain amyloidosis (AL) and hereditary transthyretin-type amyloidosis (hATTR) are two of the most common types. In amyloidosis, peripheral nervous system involvement is a significant diagnostic feature, particularly when it manifests as polyneuropathy, carpal tunnel syndrome (CTS), and dysautonomia. These neurological symptoms often point to the involvement of amyloid deposits in the peripheral and autonomic nervous systems, which can help identify and differentiate between the various types of amyloidosis. Materials and Methods: This retrospective study focused on the evolution of electrophysiological parameters in two groups: AL (n = 22) and hATTR-Glu54Gln patients (n = 14), with mixed axonal polyneuropathy. Patients were followed for two consecutive years to assess disease progression. The PND scale (polyneuropathy disability) was also used to assess motor impairment for each patient. Results: In our study AL amyloidosis patients presented with mixed, axonal polyneuropathy associated with CTS in 63.6% of cases and cardiomyopathy (45.5%). Serial EMGs (electromyography) showed decreased motor amplitudes of the common peroneal and tibial nerves and sensory amplitude of the superficial peroneal nerve, with mostly preserved conduction velocities. The patients maintained stage I PND throughout the monitoring period. The entire hATTR group displayed mixed, axonal polyneuropathy and cardiomyopathy; 85.7% of them had CTS, and 42.9% had orthostatic hypotension. EMG data showed decreased motor amplitudes of the tibial and common peroneal nerves, decreased sensory amplitudes of the superficial peroneal nerve, and mildly reduced conduction velocities, with significant progression at 12 and 24 months. The patients displayed additional reduced muscle strength, some reaching stage 3A and 3B-PND at the end of the study. Conclusions: The amyloidotic polyneuropathy found in the groups was similar in its axonal, sensory-motor, and length-dependent characteristics, but the study showed significant differences in its progression, with more abrupt changes in the hATTR-Glu54Gln group. The amyloidosis AL patients remained in stage 1 PND, while the hATTR-Glu54Gln patients progressed to stage 3 PND at 24 months.

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Monoclonal gammopathies of clinical significance (MGCSs) are entities in which a small hematological clone produces a monoclonal immunoglobulin capable of causing organ damage. Neurological involvement remains difficult to diagnose and treat, especially in the context of incidental monoclonal gammopathy of undetermined significance (MGUS)–peripheral neuropathy (PN) associations. We conducted a single-center retrospective study at Fundeni Clinical Institute, Bucharest, from January 2015 to December 2025. The reference population included 300 patients with MGUS. The diagnosis of MGNS was established clinically and/or electrophysiologically, with the exclusion of alternative causes of neuropathy. In total, 35 patients with MGNS were identified (prevalence 11.7%). Neuropathy was more common in IgM MGUS (36.7%) compared to IgG (15%), IgA (14.3%), or light chain MGUS (16.7%), with an increased risk for IgM (OR 3.27, p < 0.001). A total of 88.5% of patients received hematological treatment; neurological response was noted in the majority of treated patients. Mortality was 14.3%, and median OS was not reached. Our findings confirm the dissociation between low clonal load and the severity of organ involvement. IgM MGUS is associated with a significantly increased risk of neuropathy, supporting the need for systematic screening for MGUS in patients with PN and for a multidisciplinary approach.

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