Pediatric autosomal dominant cerebellar ataxia

Introduction

Introduction to autosomal dominant cerebellar ataxia in children There are many types of autosomal dominant cerebellar ataxia (autosomaldominantcerebellarataxia, ADCA). Pathological changes involve the cerebellum and its afferent and efferent pathways. In addition to cerebellar neuron loss, the spinal cord, pons, olive nucleus, basal ganglia, optic nerve, retina and peripheral neuropathy can also be seen. The clinical features are progressive torso support. Disorders, dysarthria, poorly resolved, intentional tremor and other simple cerebellar symptoms can also be seen in involuntary movements, visual or auditory disorders, extraocular muscle paralysis, pyramidal tract signs, paresthesia, cranial nerve palsy. Common combinations of various clinical symptoms: simple cerebellar sign, cerebellar sign and brain stem sign, cerebellar and basal ganglia syndrome, spinal cord or peripheral neuropathy, cerebellar sign and special sensation (auditory, visual) disorder, cerebellum and pituitary dysfunction, Cerebellar and myoclonic syndrome, cerebellum and increased cone tone. In recent years, several types of mutations in the trinucleotide repeat expansion, called dominant spinal cerebellar ataxia (SCA), have been found to be divided into more than 10 subtypes, with the most common CAG trinucleotide repeat extension. The following is only a discussion of the nucleus nucleus red nucleus pallidus Lewis nuclear atrophy, SCA-3 and its allelic disease Machado-Joseph disease. Machado-Joseph disease (MJD) is characterized by progressive degeneration of the motor system, that is, the cerebellar system, the pyramidal system, the extrapyramidal system, and the anterior horn motor unit have extensive degeneration. It is considered that MJD is the most common spinal cerebellar degeneration disease, and China also has Report (Zhou et al., 1997). basic knowledge The proportion of sickness: 0.00025% Susceptible people: young children Mode of infection: non-infectious Complications: chronic progressive extraocular muscle paralysis

Cause

Etiology of autosomal dominant cerebellar ataxia in children

(1) Causes of the disease

The disease is autosomal dominant.

(two) pathogenesis

The MJD gene is located on chromosome 14q32.1 and is a trinucleotide (CAG) repeat spread disease. Normal human CAG is 13 to 36 copies. The disease contains a normal allele and a 68-79 CAG. Copy extended alleles, Zhou et al. showed that the number of repeats of normal Chinese CAG was 14-40, and that of MJD patients was 72-86. There was no crossover between normal and patient, the number of CAG expansion and age of onset. In inverse proportion, the more the number of expansion, the earlier the onset, the early onset of genetics, the next generation is earlier than the previous generation, in addition, the dominant hereditary spinocerebellar ataxia type 3 (SCA-3) and the disease are Allelic diseases are caused by mutations in the MJD-1 gene, but are mainly found in adults, indicating that this mutation has significant clinical heterogeneity.

Cerebellar dentate nucleus and red nucleus degeneration, neuronal loss in the substantia nigra and striatum, degeneration of the pyramidal tract and surrounding motor units, and ultimately all motor system degeneration.

Prevention

Prevention of autosomal dominant cerebellar ataxia in children

Do a good job in the prevention and treatment of hereditary diseases.

Complication

Pediatric autosomal dominant cerebellar ataxia complications Complications chronic progressive extraocular muscle paralysis

There may be progressive extraocular muscle paralysis, exophthalmos, nystagmus, and peripheral muscular atrophy.

Symptom

Children with autosomal dominant cerebellar ataxia symptoms Common symptoms Ocular eye muscle tension reduction reflex abnormal gait instability dysarthria hearing impairment autosomal aberration

The onset is mostly in adolescence and adults. There are also those who are 5 years old. They have ataxia at the beginning of the disease, gait is unstable, and the difference is poor. The nystagmus, sputum reflexes are reduced or hyperthyroidism, muscle tension is reduced, from childhood. Patients often have dystonia as the first symptom, and there may be progressive extraocular muscle paralysis, exophthalmos, nystagmus, and common peripheral muscle atrophy in the elderly. It can also be seen in the facial muscles, fibrillation of the lingual muscles or movement of the hands and feet. MJD has obvious phenotypic heterogeneity. In the same family, some have main symptoms of dystonia, some are mainly ataxia or pyramidal tract, and others are muscle atrophy. Those who have a slower course of disease die in middle-aged and older people.

Examine

Examination of autosomal dominant cerebellar ataxia in children

A chromosomal examination can diagnose this disease.

EEG and neurological imaging examinations are routinely performed.

Diagnosis

Diagnosis and diagnosis of autosomal dominant cerebellar ataxia in children

According to family history, clinical manifestations and molecular genetic tests can be diagnosed.

Chromosome gene testing can be distinguished from autosomal recessive cerebellar ataxia.

Was this article helpful?

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.