Sarcoidosis of the nervous system

Introduction to nervous system sarcoidosis Sarcoidosis, also known as sarcoidosis, is a chronic granulomatous disease of unknown cause that can invade multiple organs throughout the body with the highest incidence of lung and lymph nodes. About 5% of patients with sarcoidosis invade the nervous system and show signs of neurological damage called neurosarcoidosis. Nervous system sarcoidosis can be recurrent. According to statistics, about one-third of patients may have recurrent disease, and non-recurrent neurological sarcoidosis accounts for about 68%. basic knowledge The proportion of sickness: 0.002% - 0.005% Susceptible people: no special people Mode of infection: non-infectious Complications: erythema, hemoptysis

Causes of nervous system sarcoidosis

(1) Causes of the disease

The cause of neurological sarcoidosis (neurosarcoidosis) is still not fully understood.

(two) pathogenesis

Sarcoidosis granuloma is most likely to invade the basal pia mater, thickening it, losing transparency, brown, with small plaques. Microscopic examination: multiple non-case granuloma uniformly distributed around the meningeal vessels Or granulomatous vasculitis, inflammation may involve the meningeal artery, vein, basilar artery and its branch of the outer membrane, less invasion of the middle layer of the blood vessels, intact intima, damage to the brain parenchyma is mostly on the screen, showing space-occupying lesions, lesions Can be single or multiple, the boundary with the surrounding tissue is unclear, a few can have an envelope, when the spinal cord is invaded, the appearance of the spinal cord can be normal, atrophy or similar intramedullary tumor, microscopic examination: dura mater, arachnoid, pia mater Gray matter and white matter may have granuloma infiltration, often accompanied by lateral cord and posterior cord demyelination. When peripheral nerve damage occurs, small vascular granuloma is mainly located in the small vessels of the epicardium and nerve space. With axonal degeneration and demyelination changes, when the muscles are involved, there is a granuloma infiltration of the endomysium and muscle fascia. In the early stage of the disease, the muscle fibers can be invaded, and extensive muscle fiber interstitial infiltration can occur later. Sexually replaced by connective tissue, the histological changes of neurological sarcoidosis are the same as those of other organs. They are non-caseous epithelial granulomas, mainly composed of epithelioid cells, accompanied by multinucleated giant cells and a small number of lymphocytes. In the giant cells, there are occasional inclusion bodies such as stellate or Schaumann bodies, which are free of cheese necrosis and negative for acid-fast staining. Silver staining shows that there are abundant reticular fibers in and around the nodules.

Nervous system sarcoidosis prevention

There are no better preventive measures for nervous system sarcoidosis. Early diagnosis and early treatment, while maintaining low-dose hormone maintenance during remission, may improve the prognosis.

Nervous system sarcoidosis complications Complications

In addition to the above manifestations of neurological damage, there may be skin, lymph nodes, lungs and other organ involvement, which may be characterized by skin nodular erythema, lymphadenopathy, cough, cough and hemoptysis.

Symptoms of Nervous System Sarcoidosis Common Symptoms Myalgia Dementia Nodules Tension Inability Consciousness Disorders Paraplegic Finger Ends Continue to... Peripheral Nerve Damage

Most of them are slow onset, the severity of symptoms of nervous system damage and the activity of nodular granuloma, the location and extent of the lesion.

1. Brain damage: Nervous system sarcoidosis mainly involves meninges, meninges, brain parenchyma, hypothalamus and pituitary gland, meningeal lesions, mainly chronic meningitis, patients with headache, vomiting, neck stiffness or companion Seizures, arachnoid arachnoid involvement, may have most of the brain damage, meningeal involvement often accompanied by hypothalamic, pituitary damage, may have diabetes insipidus, autonomic dysfunction and abnormal blood prolactin levels, brain Substantial damage is also common, mainly around the ventricle and ependymal involvement, manifested as single or multiple nodular granulomas, patients often have headache, vomiting, optic disc edema, hemiplegia, hemianopia, aphasia, multiple granuloma Damage can cause dementia, hydronephrosis often occurs in the ependymal membrane, less in the form of intracranial tumors, can be similar to meningioma and glioma, brain stem, cerebellar damage, nervous system knot Stroke-like patients with stroke-like performance are very rare, a few reports of TIA attacks, complete ischemic stroke and vascular inflammatory intracranial hemorrhage, many patients found that the disease Cerebrovascular granulomatous vasculitis, but no clinical manifestations of stroke, contrary diffuse encephalopathy sexual performance is slow, such as headaches, unconsciousness, seizures, dementia.

2. Spinal cord damage: less common, spinal cord lesions of the nervous system sarcoidosis are mostly subacute or chronic lesions, with local granulomatous infiltration and local occupying performance is more common, clinical manifestations of low back pain, leg pain, weakness, feeling Decreased or missing, paraplegia, dysfunction, etc., spinal MRI has a high value in the diagnosis of spinal cord injury.

3. Peripheral nerve damage: In patients with neurological sarcoidosis, spinal nerve involvement is the most common, as high as 6% to 18%, can appear in the absence of systemic sarcoidosis, clinically acute, subacute or recurrent It can be manifested as mononeuritis, polyradiculopathy, Guillain-Barre syndrome, symmetric polyneuropathy, etc. Cerebral nerve damage is more common in facial nerve damage, which can be expressed as peripheral facial paralysis. , hearing impairment, visual impairment and eye movement disorders.

4. Muscle system damage: It is reported that the muscle damage of this disease is characterized by granulomatous polymyositis, clinically asymptomatic, or manifested as muscle weakness, muscle atrophy, myalgia, muscle nodules, to the trunk muscle The proximal limb muscle damage is dominant, and electromyography can help to find subclinical evidence of muscle damage.

Examination of nervous system sarcoidosis

1. Lumbar puncture CSF examination: often showed abnormalities, the number of white blood cells increased significantly, mainly lymphocytes, protein content increased, about 20% of patients have CSF sugar content decreased, IgG index in CSF can sometimes increase, with or without oligoclonal Band, most of the CSF angiotensin I converting enzyme (SACE) increased.

2. Serum angiotensin I converting enzyme is obviously increased, and it has high value for the diagnosis of nervous system sarcoidosis, but it is not unique to this disease. Other diseases such as multiple sclerosis, Guillain -Barre syndrome, Behcet's disease, neurodegenerative diseases, etc. may also increase, but not as obvious as nervous system sarcoidosis.

3. Electromyography: changes in peripheral nerve damage can be found, most of which show a mild to moderate sensation, a decrease in motor conduction velocity, and a normal or light to moderate decrease in the amplitude of the mixed muscle action potential and sensory nerve action potential.

4. Most of the cerebral angiography is normal, only occasionally there is the manifestation of vasculitis. The brain CT often shows a slight increase in the density of the lesion. After the contrast agent is strengthened, the lesions are uniformly enhanced, and there may be edema around, MRI on the nervous system. The diagnosis of sarcoidosis is highly sensitive, showing a T2-weighted high-signal change in the white matter around the ventricle. The T1-weighted image is mixed with multiple signals. In the case of meningeal lesions, intensive scanning reveals meningeal enhancement.

5. Radionuclide 67 gallium (67Ga) scan has a high diagnostic value for sarcoidosis, and can detect lung lesions early. Some scholars believe that the combination of 67Ga scan and serum angiotensin I converting enzyme for the diagnosis of sarcoidosis The accuracy rate is 80% to 90%.

6. Biopsy of the meninges and brain tissue or peripheral nerves can be clearly diagnosed.

Diagnosis and diagnosis of nervous system sarcoidosis

If the nervous system sarcoidosis occurs on the basis of systemic sarcoidosis, the general diagnosis is not difficult. If the only manifestation of sarcoidosis or sarcoidosis granuloma first invades the nervous system, it often causes misdiagnosis. Unknown central nervous system, peripheral nerve and muscle system damage and endocrine dysfunction and other symptoms can be explained, especially in young adult patients, clinically highly suspected of possible neurological sarcoidosis, such as skin, lymph nodes , the history of pulmonary nodules, should consider the possibility of this disease, should be performed for lumbar puncture examination CSF, as well as MRI, CT, 67Ga scan and serum angiotensin I conversion enzyme determination, meningeal and brain tissue and peripheral nerve biopsy pathology It is an important basis for the diagnosis of this disease.

It should be differentiated from other chronic aseptic meningitis, multiple sclerosis, intracranial space-occupying lesions, cerebral parasitic diseases and cysticercosis (cysticercosis).

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