Hereditary ataxia polyneuritis

Introduction to hereditary dysmotility polyneuritis Hereditary ataxia polyneuritis, also known as Refsum disease, is an autosomal recessive hereditary disease. Its main clinical manifestations are retinitis pigmentosa, decreased vision, reduced visual field, lens opacity and peripheral nerve damage and cerebellum. Degenerative symptoms, etc., can also have multiple visceral damage. basic knowledge The proportion of illness: the incidence rate is about 0.002%-0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: nystagmus muscle atrophy

Causes of hereditary motor disorder polyneuritis

(1) Causes of the disease

The disease is autosomal recessive, mostly caused by the marriage of close relatives.

(two) pathogenesis

Under normal circumstances, the phytanoic acid from the chlorophyll intake by the human body is metabolized by oxidation. The patient of this disease cannot decompose phytanic acid due to congenital enzyme deficiency, so that phytanic acid can accumulate in the tissues of the body and cause disease. Limiting the intake of phytanic acid-containing foods, reducing the amount of phytanic acid in the blood of patients, can reduce the symptoms of polyneuropathy and cerebellar ataxia, indicating that the increase of phytanic acid is closely related to the disease.

The main pathological changes of the disease are diffuse, nodular hypertrophy, loss of myelin sheath, axonal destruction, collagen fiber and Schwann cell proliferation, formation of onion-like changes, and adipose tissue often in cells. In vivo deposition, the muscle fibers innervated by the affected nerve can also be atrophied. Electron microscopic observation reveals that the anterior horn cells of the spinal cord are degenerated, the posterior nerve fibers are reduced, the cerebellum and brainstem nerve fibers are reduced, demyelination, nerve cell degeneration, and arachnoid membrane can be atrophied. Pial thickening, fat infiltration, and fat deposition in organs such as liver and kidney.

Hereditary dysmotility prevention of polyneuritis

Genetic counseling, prevention measures include avoidance of close relatives, carrier genetic testing and prenatal diagnosis and selective abortion to prevent the birth of children.

Hereditary ataxia polyneuritis complications Complications, nystagmus, muscle atrophy

As the disease progresses, a variety of symptoms and signs can occur.

Hereditary dysmotility, polyneuritis, common symptoms, positional awareness, hypokinetic sensation, nystagmus, gait instability, sensory disturbance, peripheral nerve damage, dysmotility, ocular muscle fascia, tremor, muscle atrophy

The disease usually begins to develop around the age of 20, showing a latent onset, slowly progressing, some patients may have temporary relief during the onset of illness, and sudden death due to heart disease.

1. Patients with ocular symptoms may show night blindness and reduced visual field. This is mainly due to atypical hyperpigmentation retinitis. It is also characterized by dilated pupils, light reflexes or dysregulation, and some patients may have cataracts.

2. Neurological symptoms The neurological symptoms are mainly chronic progressive multiple peripheral neuropathy, which is characterized by distal symmetry muscle weakness of the extremities, muscle atrophy, often starting from the distal extremities, gradually proximal development, muscle atrophy to the extremities The small muscles are mainly small, and there may be fasciculation of the muscle bundle, and the sacral reflexes are weakened or disappeared; the terminal type dysfunction is distributed in gloves and socks, firstly suffering from pain and temperature, sometimes accompanied by abnormal feeling or spontaneous pain, and the sensory disturbance is often not Constant; peripheral nerves are thick, especially the ulnar nerve, the phrenic nerve and the auricular nerve are the most obvious, the brain is often involved, mainly for the auditory nerve, can be expressed as neurological deafness, sometimes one of the first symptoms, vestibular nerve function Unaffected, occasionally extraocular muscle spasm, cerebellar symptoms often appear, began to appear gait instability, followed by two-handed intentional tremor, rotational movement awkward, can not walk straight, nystagmus and language barriers.

3. Other manifestations Others may have skin ichthyosis changes; cardiac hypertrophy, increased heart rate, electrocardiogram damage of cardiomyopathy, abnormal bones, shoulder, elbow, knee joint bone formation disorder, manifested as deformation, scoliosis, in addition, Some patients may be associated with metabolic diseases such as diabetes.

4. Auxiliary examination of cerebrospinal fluid examination, cell number, chloride and sugar are normal, protein content in cerebrospinal fluid is often significantly increased, showing protein-cell separation phenomenon, serum, red blood cells, liver, heart, kidney and striated muscle phytanic acid content increased Specific changes in the disease, serum fatty acids can be increased by 10% to 20%, EMG is neurogenic damage, there may be positive sharp waves, fibrillation waves, the number of action potentials decreased, peripheral nerve conduction velocity slowed, phrenic nerve Biopsy showed hypertrophic interstitial nerve damage, Schwann cells and collagen fibrosis, which can be expressed as "onion head" changes.

Examination of hereditary ataxia polyneuritis

1. Cerebrospinal fluid examination of the number of cells, chloride and sugar are normal, protein content in cerebrospinal fluid is often significantly increased, showing protein-cell separation.

2. The content of phytanic acid in serum, red blood cells, liver, heart, kidney and striated muscle is increased, which is a specific change of the disease.

3. Serum fatty acids can be increased by 10% to 20%.

4. Genetic testing diagnosis.

5. EMG examination is neurogenic damage, there may be positive sharp waves, fibrillation waves, the number of action potentials decreased, and the peripheral nerve conduction velocity slowed down.

6. The sacral nerve biopsy showed hypertrophic interstitial nerve damage, Schwann cells and collagen fibers proliferated, which can be expressed as "onion head"-like changes.

Diagnosis and differentiation of hereditary ataxia polyneuritis

According to the disease, the disease is mainly from childhood to adolescence, mainly manifested as ocular symptoms. The nervous system symptoms are mainly peripheral nerve and cerebellum; there may be visceral and skeletal damage; the reference EMG has slowed nerve conduction velocity. A preliminary break can be made, and if the serum and biopsy tissue levels of phytanic acid are increased, the diagnosis can be confirmed.

Because the disease has protein-cell separation, it needs to be differentiated from chronic Guillain-Barre syndrome. The latter has a relatively short history. There are no ocular symptoms such as retinitis pigmentosa and cerebellar ataxia. Sexual flaccid paralysis is the main manifestation, hormone therapy is effective, and can be identified with this disease.

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