Diphtheria polyneuropathy – a very rare variant of damage to the nerve trunks now, is a microbial- toxic lesion of mainly motor nerves. This is a toxic, not an inflammatory process. The breakdown of myelin and subsequent degeneration of nerve fibers begin at the terminal branches of the nerve in the muscles. Atrophy is simultaneously detected in the corresponding muscle fibers. Diphtheria polyneuropathies are manifested by paresis of the smooth muscles of the eyes (accommodation paralysis), their abducent muscles, and in particular the muscles innervated by the glossopharyngeal and vagus nerves (nasal speech, impaired swallowing, aphonia, and sometimes tachycardia). Particularly dangerous involvement of the phrenic nerve. The pseudotubetic form of polyneuropathy was also described .
Polyneuritis
Multiple lesions of the peripheral nerves are called polyneuritis (with the inflammatory nature of the process in the nerves) or polyneuropathy (with toxic, ischemic or degenerative processes in them). Syndrome of polyneuritis and polyneuropathy is manifested by signs of impaired innervation of the predominantly distal extremities. First, symptoms of irritation and prolapse in the sensitive area are found: pain, paresthesia, and then a decrease in all types of sensitivity in the distal extremities by the type of socks and gloves. Secondly, flaccid paresis or paralysis develops with the corresponding hypo – or areflexia, as well as autonomic disorders in the same distal zones: sweating, discoloration, temperature and trophic changes in the skin, nails, bone tissues (osteoporosis). With far-reaching paresis, muscle atrophy and areflexia extend to the proximal limbs. Sometimes the innervation of the cranial nerves is disturbed. The functions of the sphincters do not suffer. The described syndromes of inflammatory or inflammatory-allergic genesis (polyneuritis) develop with various infections. Moreover, in some cases, polyneuritis or multiple mononeuritis occurs due to direct infection of the nerves. This occurs with leprosy, brucellosis, leptospirosis, syphilis. In other cases, polyneuritis, being post-infectious, acts as one of the manifestations of an allergic reaction of the body to certain infections. Such are polyneuritis or multiple mononeuritis after influenza, tonsillitis, infectious mononucleosis, scarlet fever, enterovirus diseases, chickenpox, infectious hepatitis, periarteritis nodosa, hemorrhagic purpura, disseminated lupus erythematosus, rheumatoid arthritis, polymyositis , sarcoid . The allergic nature of the lesion is characteristic of both vaccinal and serum polyneuritis. In addition, polyneuritis of unknown etiology is distinguished: acute febrile polyneuritis, chronic progressive polyneuritis. There is a third group – a transition between inflammatory and toxic lesions. It, according to the classification proposed by the International Committee on Neuromuscular Diseases, is referred not to inflammatory lesions, but to toxic neuropathies . They accompany acute and chronic infections. These are polyneuritis with typhoid, paratyphoid, diphtheria, dysentery, gonorrhea, tuberculosis, septic diseases. This also includes the defeat of peripheral neurons in botulism and tetanus. Toxic are medicinal neuropathies , with poisoning by insecticides and other compounds of phosphorus, sulfur and other organic and inorganic compounds (chlorophos, carbon monoxide, carbon tetrachloride, dinitrobenzene , triorthocresyl phosphate ). The most numerous group of neuropathies is dysmetabolic – with exo- or endogenous diseases of internal organs and endocrine glands. These neuropathies are caused by a deficiency of nutrients, vitamins B1, B2, B6, B12 or folic acid. This includes neuropathies in alcoholism, beriberi, pellagra, diseases of the pancreas and thyroid gland, blood diseases, uremia, macro- and cryoglobulinemia , and pregnancy complications. Relatively rare are polyneuropathies in malignant neoplasms ( reticulosis , myeloma , visceral carcinoma) and neuropathies , genetically determined: with Refsum disease , porphyria , primary amyloidosis, neurofibromatosis . By polyneuropathy should be classified and those multiple ischemic nerve damage, which occur when an organic lesion of large vessels and in violation of the innervation of the vessels of the nerve trunks. Multiple lesions of the peripheral nerves are also classified according to some morphological or pathogenetic characters (parenchymal, interstitial, ischemic) or by clinical signs (with an ascending type of course, with a predominance of motor, hypalgesic , afferent-atactic or autonomic disorders).