Background. The use of rating scales and questionnaires is essential in an evaluation of disease course, treatment response, the disability level and quality of life in patients with chronic inflammatory demyelinating polyneuropathy. The Medical Research Council (MRC) scale and its modification Medical Research Council sum score (MRCss) are widely used for measurement of motor deficit in patients with neuromuscular disorders. However, its usage is limited by the absence of the validated version for Russian-speaking patients.Aim. To validate MRCss scale in patients with chronic inflammatory demyelinating polyneuropathy with development of a Russian version.Materials and methods. We enrolled 50 patients with chronic inflammatory demyelinating polyneuropathy (25 with typical chronic inflammatory demyelinating polyneuropathy and 25 with Lewis–Sumner syndrome). At the first step we conducted linguocultural ratification according to the standard protocol. At the second step the psychometric parameters were evaluated, such as reliability, validity and sensitivity.Results. The developed Russian version of MRCss scale demonstrated the high level of reliability, validity and sensitivity.Conclusion. As a result, we developed a validated Russian version of MRCss scale, recommended for clinical practice and research.

Background. Chronic inflammatory demyelinating polyneuropathy (CIDP) is a treatable dysimmune polyneuropathy. An objective response for pathogenic therapy is essential in diagnosis and management of CIDP. For proper assessment of patient’s complaints and evaluation of disease progression, it is recommended to use validated scales and questionnaires. The paper presents the results of the first step of Inflammatory Neuropathy Cause and Treatment (INCAT) validation in patients with CIDP.Objective: the development of the Russian version of the INCAT scale and its linguocultural ratification.Materials and methods. 15 patients with definite CIDP (according to EFNS/PNS criteria) were enrolled. Linguocultural ratification was conducted according to the standard protocol.Results. The Russian version of the INCAT scale was developed.Conclusion. We conducted the first stage of INCAT scale validation in patients with CIDP.

Spinal muscular atrophy 5q (SMA) is one of the most common inherited neuromuscular diseases in children with an autosomal recessive type of inheritance. Homozygous deletion of exons 7 or 7–8 of the SMN1 gene encoding the motor neuron survival protein is responsible for 95 % of cases. SMA is characterized by a steadily progressive course with the development of paresis, muscle atrophy, loss of previously acquired motor skills, respiratory failure and skeletal deformities. The introduction of pathogenetic therapy in recent years has significantly changed the trajectory of SMA – patients survive, restore previously lost motor skills and acquire new ones. The clinical classification, which includes 5 types of SMA, is currently not a reliable reflection of the functional state of the child in dynamics. In 2005, a functional classification was recommended based on the patient’s current status: non-sitters (lying), sitters, and walkers. The article provides a summary of historical concepts regarding functional classification in SMA patients, as well as the criteria used in clinical trials and observations. We proposed criteria for categorizing SMA patients into a specific functional class by analyzing the available literature and making recommendations on using the classification in real clinical practice.

Introduction. Despite the improving diagnostic criteria for the chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), its verification is still an issue. Objective: to study the rate and the causes of CIDP misdiagnosis. Materials and methods. We prospectively and retrospectively analyzed the clinical and paraclinical data of 223 patients admitted to the Research Center of Neurology from 2018 to 2022 with a CIDP referral. Results. We revised the CIDP diagnosis in 150/223 patients (67%; median age 55.5 [43; 63] years; 75 males and 75 females; 3-year follow-up history [1.75; 5.25].) Once the definitive diagnosis was clarified, we divided the patients into the following groups: polyneuropathy of other etiology (n = 94; 63%), other neuromuscular disorders (n = 39; 27%), CNS disorders (n = 10; 7%), no structural NS disease (n = 7; 5%). Patients did not meet the 2021 EAN/PNS diagnostic criteria at the history-taking stage in 65% of cases, at the neurological examination stage in 39% of cases, and at the electroneuromyography stage in 92% of cases. Conclusions. The rate of CIDP misdiagnosis in Russia is 67%, and most often this refers to patients with polyneuropathy of other etiologies. The main cause for the CIDP misdiagnosis was inaccurate electroneuromyography. We should bear in mind that CIDP is a rare disorder with an extensive differential diagnosis, so it should be verified according to the current 2021 EAN/PNS diagnostic criteria.

Limb-girdle muscular dystrophies (LGMD) constitute a heterogeneous group of genetic disorders characterized by progressive muscle weakness and atrophy, predominantly affecting the muscles of the pelvic and shoulder girdles. LGMD R27, linked to biallelic pathogenic variants in the JAG2 gene, was recently described, and to date, only 27 cases has been published in three reports. Here, we present two siblings exhibiting a severe clinical phenotype of LGMD R27, associated with a novel JAG2 homozygous frameshift variant [c.3467_3470dup, p.(Pro1158AlafsTer22)] results in truncated protein with 21 amino acid substitution within the cytoplasmic domain of the Jagged2 protein.