Chronic inflammatory demyelinating polyneuropathy (CIDP) is among the key reasons of chronic polyneuropathies in adults. Diagnostic algorithm of CIDP in adults is presented. Diagnosis of CIDP is based on clinical and electrodiagnostic criteria of European Federation of Neurological Societies/Peripheral Nervous System in 2010. Principles of CIDP treatment are discussed, including modern trends of standard and 10 % IVIG solutions. 

Pompe disease (PD) is a rare, progressive, commonly fatal inherited autosomal recessive disease that is difficult to diagnose due to its obvious clinical heterogeneity and low awareness among physicians. Access to the laboratory diagnosis of rare diseases increases every year. In the past several years, Russian and foreign laboratories have achieved considerable success in accelerating and improving the diagnostic accuracy of PD. Unfortunately, the Russian-language literature contains scarce relevant information on the laboratory diagnosis of PD. This review is to fill up this gap. 

The quantitative ultrasound characteristics (USC) of the median, ulnar nerve at different levels and the spinal nerves in patients with multifocal motor neuropathy (MMN; n=13; 40,4 ± 12,6 years old) and chronic inflammatory demyelinating polyneuropathy (CIDP; n = 7; 47,3 ± 11,2 year old) did not reveal statistical difference in cross sectional area (CSA) between analyzed groups. Patients with MMN have more pronounced asymmetry of CSA in comparison with CIDP patients which have a symmetrical pattern of diffuse nerve involvement. Quantitative USC has shown to be not informative enough in differentiation of MMN and CIDP. The qualitative analysis (QA) according to 3 described types of nerve changes has shown that CIDP is characterized by the prevalence of type 3 pattern (85.8 %) while MMN – by type 2 (69.2 %). The sensitivity and specificity of proposed QA patterns in nerve USC need to be analyzed in additional investigations. 

Myotonia congenital (MC) is the most common form of the hereditary nondystrophic myotonias caused by mutations in the skeletal muscle chloride channel gene (CLCN1) which change the functional features of muscle fibers membrane. MC is represented by two allelic forms with different types of inheritance: Thomsen’s myotonia congenita (TMC) with an autosomal dominant and Becker’s myotonia congenita (BMC) with an autosomal recessive inheritance. Both forms, TMC and BMC have the same clinical manifestation: skeletal muscle hypertrophy, transient weakness, generalized myotonia, debut in early childhood and a stationary development. Diseases are characterized by equal neurophysiological changes. In the family usually only one patient is detected. In some cases with the horizontal segregation diseases, more than one mutation in CLCN1 gene is found. These factors complicate the diagnosis of TMC and BMC, further medical and genetic counseling of the family members even after the patient’s genotype is detected. The confirmed BMC case with pseudo dominant type of inheritance and limited clinical manifestation is discussed in the light of differential diagnosis of the two discussed diseases. 

Miyoshi myopathy (MM) is a rare distal form of limb-girdle muscular dystrophies characterized by weakness primarily affecting the calves in adolescence or young adulthood, with slow progression, the ascending pattern of involvement of muscle groups in an atrophic process, and with obvious clinical polymorphism at onset (3 allelic variants are described). In MM, hypercreatine phosphatemia is noted to be 20– 50 times the normal blood concentrations. MM is referred to the dysferlinopathies with different mutations in the DYSF gene. 

In that manuscript we describe a 20-year familial case of 2 brothers with MM, including changes in their clinical manifestations, biochemical, CT and EMG parameters. The diagnosis was verified by whole exome sequencing of the DYSF gene to identify a homozygous missense mutations (c. 5302C>T) leading to replacement in the polypeptide chain of DYSF p.Arg1768Trp. The differential diagnosis of MM with clinically similar hereditary neuromuscular diseases is discussed.