Nodopathy: clinic, diagnosis, treatment. Clinical description

AIM: Evaluation of the significance and possibilities of laboratory-instrumental diagnostic methods in establishing the diagnosis and selection of targeted therapy in patients with nodopathies.

MATERIALS AND METHODS: System analysis of data from foreign and domestic literature with the presentation of a clinical case.

RESULTS: Polyneuropathies are classified as demyelinating or axonal based on electrophysiological studies. However, in 2015, in addition to axonal and demyelinating neuropathies, it was proposed to distinguish a separate pathophysiological group — nodopathies. The pathogenesis of nodopathies may differ depending on the type of ion channels involved in the process, but always leads to a loss of excitability of the axon membrane; in the nodal region the membrane becomes inexcitable. Such neuropathies are characterized by transient conduction blocks followed by the development of axonal degeneration. Typical examples of nodopathies are acute motor axonal neuropathy, as well as multifocal motor neuropathy. Current pathophysiological understanding of specialized nodal regions (nodes of Ranvier) and associated axoglial proteins is growing. Hypotheses have been put forward about their role in the pathogenesis of immune-mediated attack on the peripheral myelinated axon. Recently, high titers of antibodies directed against a number of key adhesion molecules have been identified in both acute and chronic inflammatory neuropathies. These facts add to the differences in differential diagnosis between axonal and demyelinating peripheral neuropathies. New disease classification schemes based on seropositivity, improved electrophysiological and ultrasound classification, and identification of putative underlying pathological targets and mechanisms are being rapidly developed.

CONCLUSION: Using our clinical example, we demonstrated the capabilities of laboratory and instrumental diagnostic methods in establishing a diagnosis in a patient with one of the forms of nodopathies — multifocal motor neuropathy.