basal nucleus calcification
Introduction
Introduction to basal calcification Basal calcification, idiopathic basal gangliacalcification (IBGC), also known as Fahr disease, was first reported by Fahr (1930). Calcification of bilateral symmetry basal ganglia caused by multiple causes is called bilateral symmetry basal calcification syndrome or Fahr syndrome. The calcification of globus pallidus and caudate nucleus is more common in the elderly, and normal people can also appear. Calcium spots appear after 40 years old. Most people think about physiology, no clinical significance, but if the early X-ray film of the skull found basal calcification should be considered abnormal. In addition to basal calcification, there is cerebellar calcification. With the popularity of CT scans in China, the discovery of calcification of basal ganglia has increased significantly. Some are calcified on one side of the basal ganglia, but most are calcified on both sides of the basal ganglia basic knowledge The proportion of illness: 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: dementia
Cause
Basal nucleus calcification etiology
(1) Causes of the disease
The cause is unknown and is currently considered to be mainly related to the following factors:
Genetic factors (20%):
Mostly distributed, there are also reports of familial morbidity, showing autosomal recessive or dominant inheritance. Gene chain inheritance is a phenomenon similar between biological parents and offspring, and between offspring individuals. Genetics generally refers to the phenomenon that the traits of the parent are expressed in the next generation, but genetically refers to the phenomenon that the genetic material is passed from the upper generation to the offspring.
Exogenous toxicants (15%):
Activation of glutamate receptors in the brain produces neurotoxic effects leading to calcium deposition. The relative ability of an exogenous chemical to cause damage after it contacts the body or enters a susceptible part of the body.
Abnormal iron and calcium phosphate metabolism (18%):
It plays an important role in the pathogenesis of Fahr disease.
Immunity factor (10%):
Immune factors may also cause basal calcification.
(two) pathogenesis
Fahr disease is currently considered to be a neurodegenerative disease, and the mechanisms associated with the cause are as follows:
Genetic factor
Geschwind et al. investigated a significant genetic predisposition and found that the age of onset of patients was earlier than that of the first generation. The 24 patients in the family were detected by microsatellite DNA polymorphism markers and found D14S1014, D14S75, D14S306 on the long arm of chromosome 14. There is a significant linkage relationship, suggesting that genetic factors play a significant role in the occurrence of this disease, some patients may be associated with other hereditary diseases, the most common is pseudohypoparathyroidism type 2, refractory anemia.
2. Exogenous toxicants
It activates glutamate receptors in the brain and produces excitatory neurotoxic effects, which cause calcium to deposit in certain brain regions. Someone injected ibotenic acid into the basal nucleus of rats, and after 3 weeks in hypertrophy Calcium deposits are found in the cells. The main components are calcium and phosphorus. They can also contain sulfur, aluminum, silicon, etc., which are similar to the pathological changes of this disease.
3. Iron and calcium phosphate metabolism abnormalities
Some familial patients have significant iron metabolism disorders, such as decreased serum ferritin levels, decreased serum iron and iron binding capacity, iron deposition in liver, spleen, bone marrow, and brain biopsy, mainly caused by iron transport defects, and some patients appear Primary hypocalcemia may be associated with hypoparathyroidism and cerebellar calcification.
4. Immunity factors
Some patients with rheumatoid arthritis in the young people, found that the erythrocyte sedimentation rate increased significantly, CRP, RA factors, anti-nuclear antibodies also increased, some cases of biopsy found inflammatory cell infiltration around the calcium spots.
The main pathological changes: bilateral basal ganglia (cylakoid nucleus, lenticular nucleus) visible calcification plaque, sometimes involving the cerebellar dentate nucleus and cerebral cortex, plaques are mostly located in the outer cytoplasm of the vascular cells, a few are located in the synapses of glial cells Brain biopsy can show a large number of poorly differentiated astrocyte proliferation, and even astrocytoma, mainly located in the early calcification plaque formation area or large calcification plaque, the plaque is mainly composed of glycoprotein, calcium salt and iron. Dementia patients with Fahr disease are different from Alzheimer's disease and Pick disease, characterized by lack of senile plaques; a large number of neurofibrillary tangles in the neocortex of the brain; calcareous deposits; moderate to severe demyelination and nerve fiber hyperplasia in some white matter; Meynert nucleus can be seen in mild to moderate neuronal loss.
Because the acidic mucopolysaccharide is deposited in the glial cells or in the peripheral region of the cells, non-calcium circles are formed, which are mainly distributed around the blood vessels, and finally invade the blood vessel wall, and then calcium salt deposition of hydroxyapatite occurs, and a small amount of iron is formed. It can also be deposited.
Prevention
Basal nucleus calcification prevention
It is currently believed that Fahr disease is a neurodegenerative disease, prevention is related to the cause, and there are genetic backgrounds. Preventive measures include avoidance of close relatives, genetic counseling, carrier genetic testing, prenatal diagnosis and selective abortion to prevent children. Born.
Early diagnosis, early treatment, and intensive clinical care are important for improving the quality of life of patients.
Complication
Basal calcification complications Complications dementia
Some patients have mental disorders. Dementia is one of the most common clinical manifestations of the disease. Early manifestations of mental decline, mostly occult, followed by memory, language, time and spatial orientation.
Symptom
Basal nucleus calcification symptoms Common symptoms Intelligent decline obsessive-compulsive behavioral dementia calcification, apathy, manic depression, cerebellar ataxia, mental disorder, bilateral hand and foot
1. Familial cases are more frequent than puberty or early adulthood, with early hereditary signs, some patients with rare genetic diseases, such as pseudohypoparathyroidism type 2, refractory anemia, multiple autoimmune Endocrine gland diseases, etc., mainly manifested in various dyskinesias, such as torsion spasm, unilateral or bilateral acromegaly, tremor and ataxia, etc. Parkinson syndrome and torsion spasm with prominent muscle rigidity can be seen. Motility, hand and foot hyperactivity can disappear completely with the course of the disease, leaving only the symptoms of Parkinson syndrome.
2. Parathyroid hypofunction or pseudohypoparathyroidism associated with abnormal calcium and phosphorus metabolism accounts for about 2/3 of the basal ganglia calcification.
Fahr syndrome caused by primary hypoparathyroidism, long course of disease, multiple episodes of hand and foot convulsions, dance, hand-foot or Parkinson's disease-like manifestations, cerebellar ataxia or a small number of patients with bilateral Limb pyramidal tract sign positive, diagnosis of primary hypoparathyroidism should be consistent with: no history of trauma or thyroid surgery, hypocalcemia, hyperphosphatemia, chronic seizures of hand and foot "twitching" history.
3. Some patients have mental disorders, such as depression, mania, compulsive behavior, aggressiveness, irritability, apathy, gender inversion, paralysis, etc. Dementia is one of the most common clinical manifestations of the disease, but different types of Fahr disease dementia In Alzheimer's disease and Pick's disease, it is a mixture of the two, the early performance of mental decline, mostly occult, followed by memory, language, time and spatial orientation loss.
Examine
Examination of basal calcification
1. Serum calcium content is normal, but with hypoparathyroidism or pseudohypoparathyroidism, serum calcium is reduced, and there is clinical manifestation of low calcium.
2. Blood routine, biochemistry, cerebrospinal fluid routine examination without specificity.
3. Drugs, trace elements and biochemical tests help to diagnose the cause.
4. CT examination
It can be seen that the symmetry basal ganglia calcification >800mm2 is an important diagnostic criterion for the disease. The cerebellar dentate nucleus and cerebral cortex may also have calcified plaques.
5. MRI examination
The brain basal ganglia and some gray matter T2WI high signal, with dementia can be seen in the bilateral semi-oval center area high signal, SPECT examination found that bilateral basal ganglia cerebral blood flow is significantly lower than the cerebral cortex, blood flow reduction degree and disease severity is positive ratio.
Diagnosis
Diagnosis and identification of basal calcification
Diagnostic criteria
According to the symptoms of dyskinesia, with mental disorders, mental decline, CT, MRI can be seen bilateral bilateral basal nucleus symmetric calcification, a family history more support for diagnosis.
Actively looking for the cause, specifically for the idiopathic or some special causes of Fahr syndrome, Moskowitr (1971) proposed a new diagnostic criteria for Fahr disease:
1CT or X-ray film has bilateral basal nucleus symmetric calcification;
2 no clinical manifestations of pseudohypoparathyroidism;
3 serum calcium, phosphorus in the normal range;
4 renal tubules respond normally to thyroxine;
5 no infection, poisoning and other causes;
6 with or without family history.
The basal calcification found in the cause is Fahr syndrome.
Differential diagnosis
1. Hypoparathyroidism and pseudohypoparathyroidism are the most common causes of Fahr syndrome. Patients with reduced serum calcium levels, hand, foot and ankle, convulsions, pseudohypoparathyroidism type 2 is a rare familial Inherited diseases, in addition to signs and symptoms of hypoparathyroidism, there are obvious bone and body development disorders.
2. Childhood intracranial infection can cause basal ganglia calcification, Bobek et al reported 2 cases of childhood meningoencephalitis, a series of clinical symptoms of basal calcification.
3. The main cause of neonatal Fahr syndrome is birth injury, severe hypoxic ischemic encephalopathy, intrauterine asphyxia, etc., which can cause a series of manifestations of Fahr syndrome within a few months, and the history can be identified.
