Polyneuropathy - Symptoms

In the clinical picture of polyneuropathy, as a rule, signs of damage to motor, sensory and vegetative fibers are combined. Depending on the degree of involvement of fibers of various types in the neurological status, motor, sensory or vegetative symptoms may predominate.

[1], [2], [3], [4], [5]

Symptoms

The defeat of motor fibers leads to the development of flaccid paresis, for the majority of neuropathies is characterized by the defeat of the upper and lower extremities with a distal distribution of muscle weakness, with prolonged existing axon lesions, muscle atrophy develops. For axonal and hereditary polyneuropathies, the distal distribution of muscle weakness is typical, the defeat of the lower extremities predominates, the weakness is more pronounced in the extensor muscles than in the flexor muscles. With pronounced weakness of the peroneal group of muscles, the steppe develops ("cock's gait"). Acquired demyelinating polyneuropathies may manifest as proximal muscle weakness. In severe cases, there may be a lesion of the cranial nerves and respiratory muscles, which is most often observed with Guillain-Barre syndrome.

For polyneuropathies, the relative symmetry of symptoms is characteristic. Asymmetric muscle weakness and atrophy are observed in multiple mononeuropathies: multifocal motor neuropathy, Sumner-Lewis multifocal sensomotor neuropathy.

Tendon and periosteal reflexes in polyneuropathy usually decrease or fall out, first of all, reflexes from the Achilles tendon decrease, with further development of the process - knee and carporadial, tendon reflexes from the two-headed and three-headed muscles of the shoulder can be kept for a long time. With multiple mononeuropathies, tendon reflexes can remain preserved and even animated for a long time.

Sensory disorders in polyneuropathy are also often relatively symmetrical, initially appear in the distal areas (such as "socks" and "gloves") and spread proximally. In the onset of polyneuropathy, positive sensory symptoms (paresthesia, dysesthesia, hyperesthesia) are often detected, but with further development of the process the symptoms of irritation are replaced by symptoms of prolapse (hypoesthesia). The defeat of thick myelinated fibers leads to violations of deep and vibrational sensitivity, the destruction of thin myelinated fibers - to the violation of pain and temperature sensitivity.

A characteristic feature of many polyneuropathies is the pain syndrome, which is most characteristic for diabetic, alcoholic, toxic polyneuropathies, porphyria polyneuropathy, and others.

Violation of autonomic functions is most clearly manifested in axonal polyneuropathies, since vegetative fibers are non-myelinated. The symptoms of prolapse are more often observed: the defeat of sympathetic fibers in the peripheral nerves is manifested by the dryness of the skin, a violation of the regulation of vascular tone; the defeat of visceral vegetative fibers leads to disautomonomy (orthostatic hypotension, tachycardia, decreased heart rate variability, abnormal gastrointestinal function, decreased erectile function). Signs of disautonomy are most pronounced in hereditary vegetative-sensory polyneuropathies, diabetic polyneuropathy. Violation of autonomic regulation of the heart can cause sudden death. Vegetative manifestations of polyneuropathies can also manifest symptoms of irritation (hyperhidrosis, vascular tone disruption), which is often noted in vibrational disease, porphyria polyneuropathy.

Clinical manifestations of neuropathy are composed of symptoms of three types: sensitive, motor and vegetative. Vegetative disorders with polyneuropathies are more common. Isolated forms of neuropathic syndromes, in which the syndrome of progressive autonomic failure is formed. In this case, the symptoms of vegetative insufficiency can obscure the manifestations of the underlying disease and are primarily due to visceral polyneuropathy. A similar example is diabetic polyneuropathy accompanied by severe orthostatic hypotension, impotence, impaired sweating, and a change in pupillary response. Similar disorders are found in patients with amyloid neuropathy.

Peripheral autonomic disorders are manifested by painful, vascular and resistant trophic phenomena. The most vivid and intense vegetative disorders in the limbs are observed with hereditary sensory neuropathy. This category includes a number of diseases characterized by a marked loss of sensitivity or autonomic dysfunction or a combination of these disorders. An essential feature of these forms is the presence of severe trophic disorders, especially in the lower extremities. There are indications of the presence in some cases of hereditary perforating foot ulcers. The disease, as a rule, begins with the loss of pain and temperature sensitivity in the distal parts of the lower extremities, then similar changes in the upper limbs are attached. Other types of sensitivity are affected, and mild motor disorders in the distal parts of the limbs may appear. The peculiarity of the disease is excruciating spontaneous pain, mainly in the legs. Frequent symptoms include neuropathic joint degeneration and persistent ulceration of the feet. The disease manifests itself early, and with a recessive-inherited variant, symptoms are observed from birth.

With such a rare form as congenital sensory neuropathy with anhidrosis, along with a delay in motor development and episodes of unexplained fever, there are loss of pain and temperature sensitivity, bone fractures, skin ulcers and occasionally gout.

The pattern of skin changes that are often the first symptom of fairly widespread forms of polyneuropathies accompanying systemic connective tissue diseases is unique and unique. The defeat of peripheral nerves can be for a long time the only clinical manifestation of a systemic disease. Most often, polyneuropathic syndromes develop in systemic lupus erythematosus, rheumatoid arthritis, systemic scleroderma, vasculitis, mixed connective tissue disease, cryoglobulinemia, Sjögren's syndrome, etc.

With some collagenoses (for example, with nodular periarteritis), the probability of damage to the peripheral nervous system is greater. Peripheral autonomic disorders are associated with the development of neuropathy, which is manifested by distal paresthesia with a decrease in sensitivity. In severe cases, the clinical picture is complicated by the manifestations of cutaneous vasculitis or concomitant articular deformities characteristic of rheumatoid arthritis, the development of trophic skin lesions - swelling of the fingers and hands, sometimes with thinning of the skin and the disappearance of skin folds, hyperpigmentation with depigmentation sites and telangiectasia, as is often observed with systemic scleroderma.

Forms

I. Classification of polyneuropathy (and in general neuropathy) according to prevailing clinical features:

1. motor (motor) neuropathy;
2. sensitive (sensory) neuropathy;
3. autonomic neuropathy;
4. mixed neuropathy.

II. Classification of neuropathy by the nature of the distribution of the lesion:

1. distal (more often symmetrical) involvement of the limbs;
2. multiple mononeuropathy (often asymmetric proximal lesion); also allocate polyneuropathy with the predominant involvement of the upper limbs and polyneuropathy with the predominant involvement of the lower extremities (the latter variant is much more prevalent in frequency of occurrence). A rare option is polyneuropathy with the predominant involvement of cranial nerves.

III. Classification of polyneuropathy by the nature of the current:

1. acute (the development of symptoms occurs within a few days);
2. subacute (within a few weeks);
3. chronic (within a few months or years).

The chronic form is divided into chronic progressive and chronic recurrent forms. An acute onset is characteristic of inflammatory, immune, toxic or vascular etiology. Polineuropathy, which develops slowly (years), indicates hereditary or, more rarely, metabolic origin. There are forms that flow throughout life.

Most of the toxic, nutritional and systemic diseases develop subacute within a few weeks or months.

Hereditary polyneuropathies

NMSH I (demyelinating) and II (axonal) types, known as the Charcot-Marie-Tous disease, generally have a similar clinical picture. The disease most often debuts in the first-second decades of life. At the onset of the disease, the symmetrical weakness of the peroneal group of muscles develops, the steppe, then the atrophies of the muscles of the feet and shins gradually appear ("stork's feet"). Weakness and atrophy of the distal muscles of the lower extremities lead to a characteristic change in the feet (the formation of a "hollow" or "horse" foot, a change in the feet of the Friedreich type). The calf muscles remain intact for a long time. Weakness in the muscles of the hands joins 10-15 years after the onset of the disease. Sensory disorders are most often represented by moderate hypoesthesia, such as "high socks" and "gloves." Paresthesia and vegetative disorders are not characteristic of hereditary polyneuropathies. Pain syndrome is rarely expressed and is most often associated with foot deformities and orthopedic disorders. The proximal muscles remain practically intact, so that patients retain the ability to move independently until the end of life. In 100% of cases, Achilles reflexes fall out, later the knees die out, then the carporadial reflexes.

The clinical picture of the Russi-Levi syndrome, a phenotypic variant of IA type IAH, includes areflexia, ataxia and tremor. For the syndrome of Russi-Levi is characterized by pronounced demyelination (the speed of carrying on the nerves of the legs does not exceed 5-16 m / s) with a relatively preserved axon function (according to the data of needle EMG, the denervation process is weakly expressed, the atrophy affects only the muscles of the feet, while the muscles shins remain relatively safe, so for this form is not typical steppe). In 50% of cases, the deformity of the feet is determined by the type of Friedreich (either high vaults of the feet), weakness of the distal muscles of the feet, hypesthesia in the distal parts of the lower extremities, a violation of the joint-muscular sense, the absence of tendon reflexes. In general, the course of the Russi-Levi syndrome is more favorable than the type INMSN of the type proceeding in the type of neural amyotrophy.

Hereditary neuropathy with a tendency to paralysis from compression is characterized by an autosomal dominant type of inheritance and manifests itself as relapsing multiple mononeuropathies. Patients are usually observed about frequent tunneling neuropathies, while it is noteworthy that local demyelination is caused by a slight compression. With further development of the process, there is a mosaic symptomatology associated with residual phenomena after the transferred tunnel syndromes.

[6], [7], [8], [9], [10], [11]

Polyneuropathy in porphyria

Acute intermittent porphyria is a hereditary autosomal dominant disease characterized by periodic attacks of abdominal pain that are combined with the acute development of polyneuropathy and various disorders of the central nervous system. The attack, as a rule, is provoked by taking alcohol or drugs, using anesthesia, stress. Characterized by the acute occurrence of abdominal pain, diarrhea with development in 2-4 days tetraparesis. In severe cases, there is a lesion of bulbar and respiratory muscles. In most cases, the attack passes without a trace after 1-2 months. Porphyria polyneuropathy is characterized by a nonclassical distribution of sensory and motor disorders (there may be a decrease in sensitivity in the proximal areas, tendon reflexes may remain intact).

Autoimmune neuropathies

The most common autoimmune polyneuropathies are acute and chronic inflammatory demyelinating polyradiculoneuropathies.

[12]

Multiple mononeuropathies

The basis of multiple mononeuropathies, or multifocal neuropathies, is focal demyelination of individual nerves. With EMG, blocks of excitation are detected on individual nerves, while neighboring nerves can be intact. Hence, the characteristic clinical sign of multiple mononeuropathies is the asymmetry of the lesion.

Among the multiple mononeuropathies of special interest are two forms - motor multifocal neuropathy and Sumner-Lewis syndrome.

Multifocal motor neuropathy with blocks of conduction

Multifocal motor neuropathy with conduction blocks - acquired autoimmune demyelinating neuropathy, characterized by the development of asymmetric slowly progressing weakness of the limb muscles (more often the arms), fasciculations, krampi and the absence of sensory disturbances. The clinical picture with multifocal motor neuropathy in many respects resembles amyotrophic lateral sclerosis (isolated motor disorders without sensory disorders, tendon reflexes are often preserved), and therefore the diagnosis of this disease is especially important, as it is amenable to therapy and has favorable treatment, in contrast to amyotrophic lateral sclerosis forecast for life.

The disease is accompanied by the formation of persistent blocks of conduction along the motor nerves in places different from those of typical tunnel syndromes. A characteristic feature is the safety of the conductive function of the sensory fibers at the site of the block for conducting on motor fibers.

Multifocal acquired demyelinating sensomotor neuropathy with Sumner-Lewis blocks

The disease is similar in many ways to multifocal motor neuropathy, but it is accompanied by the defeat of not only motor, but also sensory fibers. In the study of sensory fibers, a decrease in the amplitude of the sensory response can be detected. Earlier Sumner-Lewis syndrome was considered as a variant of chronic inflammatory demyelinating polyneuropathy, but at present it is isolated as an independent disease. It is believed that the disease has a more rapid course than multifocal motor neuropathy.

Multiple mononeuropathy with vasculitis

In vasculitis, multiple mononeuropathy of an ischemic nature with asymmetric nerve limbs is clinically often developed. Characteristic pain syndrome along the nerve. With EMG, axonal changes in clinically injured nerves are detected with a preserved conductive function of nearby clinically intact nerves. The diagnosis is refined with a nerve biopsy. Often multiple mononeuropathy arises already against the background of the established diagnosis of a systemic disease. In the case of an unidentified diagnosis, attention is drawn to unexplained weight loss, fever, arthralgia, myalgia, night sweats, pulmonary and abdominal symptoms.

Paraproteinemic polyneuropathies

Clinically, paraproteinemic polyneuropathies resemble a chronic inflammatory demyelinating polyneuropathy with mainly sensory disorders: paresthesias, hypoesthesia. Motor disorders are most often expressed moderately. The course of paraproteinemic polyneuropathies is progressive, in contrast to remitting for chronic inflammatory demyelinating polyneuropathy. With EMG, signs of demyelinating polyneuropathy are revealed.

Polyneuropathies associated with a deficiency of B vitamins

The most often deficiency of B vitamins occurs in people who suffer from alcoholism, drug addiction, HIV infection; in patients with gastrointestinal disorders, with malnutrition (for example, those who observe strict diets). With a deficiency of vitamins B ₁, B ₆, B _12, there is a sensorimotor axonal polyneuropathy beginning with the lower extremities. Typical hypesthesia in the distal parts of the limbs, weakness of the distal muscles of the legs, pain, burning sensation in the feet. For vitamin B _12- deficient polyneuropathy is characterized by a violation of deep-tissue sensitivity (a consequence of funicular myelosis), cognitive impairment is possible. Typically, deficiency of vitamin B ₁₂ is associated with resection of atrophic gastritis or stomach, resulting in disturbed secretion Castle's intrinsic factor, and hence is accompanied by symptoms of gastrointestinal and pernicious anemia (weakness, fatigue, pallor of the skin).

Diabetic polyneuropathy

The most common diabetes mellitus develops chronic axonal-demyelinating distal sensorimotor polyneuropathy. The risk of developing polyneuropathy depends on the level of glycemia and the duration of the disease. In type 2 diabetes mellitus, polyneuropathy can be one of the first signs of the disease, so when revealing a polyneuropathy of an unknown genesis, it is advisable to determine the level of glycosylated hemoglobin or to conduct a test for glucose tolerance. Less commonly observed proximal diabetic polyneuropathy, acute diabetic polyneuropathy, autonomic polyneuropathy. Diabetes mellitus also contributes to the development of neuritis and tunnel syndromes. In addition, among patients with diabetes mellitus, chronic inflammatory demyelinating polyneuropathy is more common than in the general population.

Chronic distal diabetic polyneuropathy in typical cases begins with a feeling of numbness of the I or III-V fingers of one foot, then the area of sensitivity disorders increases quite slowly, a feeling of numbness in the fingers of the second foot appears, after a while it covers the entire foot and can rise up to the knee level , at this stage the feeling of numbness of the fingertips can be added. Violated pain, temperature, vibration sensitivity, in the expanded stage of the disease, complete anesthesia may develop. Movement disorders are less pronounced. Achilles reflexes fall early. Neuropathic pains, as a rule, join after several years after the beginning of polyneuropathy, have an emotional discomfort very unpleasant for the patient, are often accompanied by agonizing allodynia and poorly treatable. Simultaneously with the sensitive disorders, trophic skin disorders of the shins develop, related both to the defeat of vegetative fibers and to microangiopathy. Vegetative disorders are not limited to the limbs; diabetes is characterized by the development of disautomonomy, manifested in insufficient autonomic regulation of internal organs (decreased heart rate variability, tachycardia, orthostatic hypotension, impotence, disruption of GIT function).

[13], [14], [15]

Uremic polyneuropathy

Ureemic polyneuropathy occurs in chronic renal failure with creatinine clearance less than 20 ml / min (often less than 10 ml / min). Usually develops the distal sensorimotor polyneuropathy. With EMG, the axonal type of changes with secondary demyelination is identified. The severity of polyneuropathy primarily depends on the duration and severity of chronic renal failure. Uremic polyneuropathy usually begins with paresthesia in the lower limbs, then weakness and atrophy of the distal muscles of the legs, then of the hands, are added. The decrease in vibration sensitivity (more than 90% of patients), the absence of tendon reflexes (more than 90%), distal hypoesthesia (16%), and krampi (67%) are characteristic. Muscular weakness is noted in 14% of patients, it is moderately expressed. In 45-59% of cases, vegetative dysfunction (postural hypotension, dizziness) is possible.

Diphtheria polyneuropathy

Diphtheria usually develops a demyelinating sensomotor polyneuropathy with a defeat of cherpenyh nerves. As a rule, polyneuropathy develops 2-4 weeks after the onset of the disease and debuts with the defeat of the cranial nerves, primarily the bulbar group, it is also possible to involve the oculomotor, facial and optic nerves in the process. Later sensorimotor neuropathy develops in the extremities with damage to the distal and proximal muscles. In severe cases, the ability to move independently is lost, there is a weakness in the respiratory muscles, which can cause the need for ventilation.

[16], [17], [18], [19], [20],

HIV-associated neuropathies

With HIV infection, various variants of peripheral nerve damage are possible. The disease can proceed as a distal symmetrical polyneuropathy, characterized by paresthesia, dysesthesia, a feeling of numbness in the feet, gradually spreading to the hands. In HIV-infected people more often than in the general population, Guillain-Barre syndrome and chronic inflammatory demyelinating polyneuropathy develop. In a number of cases, multiple mononeuropathies develop.