telangiectatic ataxia syndrome
Introduction
Introduction to telangiectasia ataxia syndrome The telangiectasia ataxia syndrome is also known as telangiectasia ataxia, telangiectasia, and Lovis-Bar syndrome. It is a rare, complex and poor prognosis of neurocutaneous syndrome. The disease is an autosomal recessive hereditary disease, but sporadic cases account for the vast majority. Its clinical features include: cerebellar ataxia in infants and young children, telangiectasia telangiectasia, recurrent paranasal sinus and lung infections, prone to malignant tumors and mixed immunodeficiency. basic knowledge The proportion of illness: 0.001% Susceptible people: infants and young children Mode of infection: non-infectious Complications: nystagmus strabismus mental retardation lymphoma leukemia breast cancer
Cause
Causes of telangiectasia ataxia syndrome
Abnormal tissue differentiation hypothesis (20%):
The normal development of the thymus depends on the interaction of the ectoderm of the epithelial tissue and the mesoderm of the differentiated lymphoid tissue. The thymic gland of this patient is dysplastic, the serum fetomegaglobulin is elevated, and the gonadal hyperplasia is low, indicating an organ system maturity disorder.
DNA synthesis and repair defect hypothesis (20%):
This seems to be the more widely accepted view. In recent years, cell culture has confirmed that the chromosomes of peripheral lymphocytes in patients with this disease are spontaneously broken, which is 40 times higher than that of normal people. This abnormal chromosome can cause signs of premature aging of hair and skin. Increased risk of complicated malignant tumors, and easy to be complicated by respiratory infections.
Autoimmune hypothesis (20%):
Kaufmann et al. found cytotoxic antibodies against thymus and nervous tissue in patients with this disease, and thought that these antibodies caused thymic dysfunction and neurological degeneration, respectively.
The prominent pathological changes of this disease are cerebellar cortical atrophy, Purkinje cells in the cerebellar cortex, granulosa cells and basket cells, and neurons in the deep cerebellum of the cerebellum are reduced. Neurons are also missing in the lower olivary of the medulla, and the spinal cord is thin. The myelin sheath of the wedge bundle is degenerated, and the anterior horn cells and ganglion cells are also damaged. Under the electron microscope, the endoplasmic reticulum cavity of Purkinje cells is enlarged, the particles are decomposed, the autophagic vacuoles increase, the electron density increases, and the lymphatic system It is often found that thymic dysplasia or deficiency, lack of Hassall body, unclear boundary between cortex and medulla, decreased lymphocyte count, increased epithelioid cells, lack of lymphoid follicles in spleen and lymph nodes, plasma cells, lymphocyte reduction, reticulate Endothelial cells increase, nearly half of patients with tumors, malignant lymphoma is common, followed by lymphocytic leukemia, also with intracranial glioma.
Other dilated capillary lines of the epidermal papillary venous venules, bronchiectasis and fibrosis in the lungs, ovarian hyperplasia, testicular stromal cells, fat cell infiltration in the liver portal, parenchymal cell swelling and vacuoles Denaturation and so on.
Prevention
Prevention of telangiectasia ataxia syndrome
Genetic disease treatment is difficult, genetic counseling should be carried out, preventive measures include avoiding close relatives marriage, carrier genetic testing and prenatal diagnosis and selective abortion to prevent the birth of children.
Early diagnosis and treatment of the sprinkler can prolong survival.
Complication
Complications of telangiectasia ataxia syndrome Complications, nystagmus, strabismus, mental retardation, lymphoma, breast cancer
With the development of the disease, a variety of symptoms and signs can occur, progressive cerebellar ataxia can be accompanied by gaze nystagmus, strabismus, eye movement difficulties, mask appearance, speech is unclear, mental retardation, etc., repeated respiratory infections are susceptible to B cells Lymphoma, leukemia, breast cancer and some endocrine diseases often die from chronic infections and tumors.
Symptom
Symptoms of telangiectasia ataxia syndrome Common symptoms Muscular atrophy dysarthria Intentional tremor Lung infection Subcutaneous fat atrophy Deep sensory disturbance Appetite loss Powerful eyeball tremor Closed eyes difficult to sign
Nervous system symptoms
The neurological symptoms of this disease are mainly cerebellar ataxia, which usually occurs in infancy. At first, it mainly affects the trunk and head. When the sick child begins to learn to walk, the gait is shaken, the legs are wide, and the upper limbs appear. Intentional tremor, closed eyes are difficult to sign positive, sick children often delay walking age, tendon reflexes weaken or disappear, tendon reflexes are flexive, most sick children may be accompanied by dance-like movements or hand-foot-motion, but may be The prominent cerebellar symptoms can be concealed, and there may be nystagmus and cerebellar dysarthria. Some children may have pseudo oculomotor nerve paralysis. When looking at the target, they often use the head, the neck and the blink, and other compensatory actions, physical and intelligent development. Hysteresis, most patients with post-pubertal symptoms of spinal cord injury, such as deep sensory disturbances and extensor tendon reflexes, can occur in adults with distal muscle atrophy, weakness and fasciculation.
2. Skin symptoms
Most patients have skin telangiectasia at 3 to 6 years old, and some cases exist at birth, but also late in puberty. The first site is the exposed part of the conjunctiva of the eye. Similar to conjunctivitis, it gradually disappears near the cornea and appears later. Frequently exposed or susceptible areas such as eyelids, bridge of the nose, cheeks, outer ear, neck, elbow fossa and armpits, skin may have brown spots, pigmentation or loss, hair dull, gray, due to facial subcutaneous Fat atrophy, skin elasticity is reduced, patients can present with a moderate scleroderma-like facial expression, in addition, chronic seborrheic blepharitis and seborrheic dermatitis are also common.
3. Other performance
Because patients often have low humoral immunity and cellular immune function, especially in patients with lack of secretory IgA, respiratory tract infections such as sinusitis, bronchitis and pneumonia, and otitis media may occur. Repeated pulmonary infection may cause extensive lung disease. Fibrosis, occurrence of clubbing (toe) and pulmonary insufficiency, etc., almost all of the sick children have sexual developmental disorders, usually do not appear secondary sexual characteristics, late stage of the disease due to limited mobility can occur after the spine, scoliosis, patients easy Malignant tumors occur, mainly malignant lymphoma, lymphocytic leukemia, etc., due to liver function involvement, loss of appetite.
Examine
Examination of telangiectasia ataxia syndrome
1. Percentage of lymphocytes in peripheral blood is reduced.
2. Immunoglobulin IgA, IgE deficiency or decrease.
3. Serum fetal globulin is higher than normal.
4. Cerebrospinal fluid examination is normal.
5. Myoelectricity shows a decrease in the amplitude of the nerve evoked potential, and in the late stage, the motor and sensory conduction velocity are slowed down.
6. X-ray examination Some patients may have chronic sinusitis or pneumonia, bronchiectasis and pulmonary fibrosis signs.
7. Cranial CT scan showed cerebellar atrophy and fourth ventricle dilatation.
Diagnosis
Diagnosis and differentiation of telangiectasia ataxia syndrome
diagnosis
According to the cerebellar ataxia in childhood, the ocular capillary conjunctival telangiectasia, repeated severe respiratory infections and other typical manifestations can be diagnosed, if the laboratory test confirms that the patient has low cellular and humoral immune function, the diagnosis is more reliable.
For some atypical cases, such as no telangiectasia; no or only history of mild respiratory infection; serum immunoglobulin is not low, or IgG is low, IgA not only does not lower but rises, etc., depends on detailed medical history, symptoms, signs A comprehensive analysis of the data such as laboratory tests can make a diagnosis.
Differential diagnosis
Early ataxia should be associated with acute infectious cerebellar ataxia, juvenile myeloid hereditary ataxia, hereditary multiple radiculitis neuritis, telangiectasia and cerebral hemangioma syndrome, cerebellum Retinal angiomatosis and other phase identification, pigmented plaque should be differentiated from nodular sclerosis, according to the clinical manifestations and laboratory characteristics of each disease identification is not difficult.
