Possibilities of pathomorphological diagnostics of neuromuscular diseases

Polyneuropathies include a wide range of diseases that are characterized by impaired function an
AIM OF THE STADY: using the possibilities of pathomorphological methods for the differential dianosis of various types of neuromuscular diseases.
MATERIALS AND METHODS: the study was performed on the current material obtained from 18 patients during operations for the removal of a nerve and a musculocutaneous flap for morphological diagnosis in patients with neuromuscular diseases. 8 drugs were studied in patients with myodystrophy and 2 drugs with spinal amyotrophy, 2 drugs with a generalized form of myasthenia gravis, motor neuron disease 2, with myositis 4.
The material was subjected to special processing methods for routine hematoxylin-eosin staining, special stains to identify nerve fiber, adipose tissue and immunohistochemistry (IhC) to determine inflammatory infiltration (CD 45), as well as vessels (CD 34).
RESULTS. With the help of a morphological study in patients with neuromuscular diseases, the following changes were revealed: with myodystrophy, a different degree of damage to the muscle fiber from 20 to 80 % was revealed, productive inflammation with the presence of plasma and giant cells in the infiltrate, which is typical for cases with the presence of genetic damage. The severity of productive inflammation is comparable to the amount of damage to the muscle fiber.
In the same preparations, different degrees of fatty degeneration are noted. There are no changes in the nervous system in muscular dystrophies. A violation of the structure of motor plaques with the disappearance of fibrillar plaques was noted. muscle fibers become thinner, replaced by adipose and connective tissue.
In the group with spinal amyotrophy, morphological features characteristic of neurogenic amyotrophy and myodystrophy are combined, however, changes in the muscle fiber are mainly associated with impaired innervation and manifest themselves in moderately pronounced dystrophic changes (protein degeneration, fatty degeneration). There was no productive inflammatory infiltration.
In patients with motor neuron disease, severe changes in the muscle fiber of a dystrophic nature were noted. Fatty degeneration occupied from 50 to 90 % of muscle fibers, nerve fibers were absent.
CONCLUSION. Thus, modern approaches to the diagnosis of neuromuscular diseases are based not only on classical clinical and laboratory research methods, but can also be largely based on morphological diagnostics. being a highly informative research method, the histological study of biopsy material requires a technically complex procedure, but when it is carried out qualified, it gives a good result.

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