Cerebral paragonimiasis
Introduction
Introduction to brain paragonimiasis Paragonimiasis, also known as pulmonary paragonimiasis, is a zoonotic disease caused by parasitic worms and Paragonimus sinensis. Cerebral paragonimiasis is a disease caused by paragonimiasis invading the brain, and is generally more common in severely infected with paragonimiasis. basic knowledge The proportion of illness: 0.001% Susceptible people: more common in children and adolescents. Mode of infection: non-infectious Complications: epilepsy
Cause
The cause of cerebral paragonimiasis
(1) Causes of the disease
Paragonimiasis is named for the juxtaposition of male and female reproductive organs. More than 50 species are known, most of which are not pathogenic to humans. Parasitic worms and Paragonimus sinensis are the most widely distributed in China, and there are many infections. It is a major pest-causing species. Its adult, worm, and egg can parasitize the brain, spinal cord and other tissues to cause lesions. Paragonimus is more common. Adults are hermaphrodite, with mouth and abdominal suction cups. Parasitic in a variety of animals, human is the appropriate terminal host of Paragonimus vaginalis, the worm can develop into an adult in the human body, the main parasitic part is the lung, the eggs can be found in the host's sputum and feces, and The gonads are not suitable for parasitic on the human body. The worms are parasitic in the connective tissue or muscle, and the growth rate is slow and cannot mature.
The life history of Paragonimus: The eggs are discharged to the outside with the cockroaches or feces of the final host. After entering the water, they mature under 3 to 6 weeks under suitable conditions, hatching the edulis, and the edulis invade the first intermediate host, the freshwater snail, in the snail. The developmental proliferation process of the scorpion scorpion, the female thunder, and the thunder, develops into a scorpion in 2 to 3 months, and the scorpion invades from the snail and invades the second intermediate host crab or scorpion to form a sac, which is eaten by humans. Live crabs can be infected after the crab or cockroach.
(two) pathogenesis
The central nervous system damage of this disease is mainly caused by adult or larvae migration. The lesions caused by eggs are of little significance. In severe cases, the worms can follow the mediastinum, rise from the carotid artery, enter the skull through the ruptured hole, and the worm The body invades the brain from the bottom of the temporal lobe or occipital lobe. It can also invade the white matter, involving the internal capsule, the basal ganglia, the lateral ventricle, and occasionally invade the cerebellum. The lesion is more common in the right hemisphere, but it can also be moved to the contralateral side via the ventricle or corpus callosum. The pathological process of this disease is divided into three phases:
1. Infiltration period or tissue destruction period: Mechanical damage and hemorrhage caused by migration in the brain of the worm, meningitis caused by toxin stimulation, encephalitis, and sometimes granuloma with unclear borders.
2. Cyst or abscess stage: The brain tissue destroyed by the worm body gradually reacts, forming a capsule around the granuloma, and its central necrosis liquefaction forms a viscous liquid of blue-gray or special brown-gray, which can have worms and eggs.
3. Fibrous scar phase: In this period, the worm has died or migrated to other places, the cystic fluid is absorbed, the granulation tissue is fibrotic or calcified, the affected cortical or subcortical structure is atrophied, and the sulci and ventricles are enlarged.
Since the worm body can cause multiple injuries in the brain tissue, the pathological changes in the above stages can exist at the same time. In a few cases, the worm body can also invade the psoas muscle and the deep spinal muscle through the abdominal cavity and enter through the adjacent intervertebral foramen. The formation of cysts in the spinal cord cavity oppresses the spinal cord, causing movement, sensory disturbances, severe cross-sectional myelitis, and even paraplegia.
Prevention
Cerebral paragonimiasis prevention
Actively treat patients, strengthen health education in endemic areas, do not drink raw water, do not eat raw or half-lived crabs and clams.
Complication
Complications of cerebral paragonimiasis Complications
Cerebral paragonimiasis may be associated with increased intracranial pressure, complications such as epilepsy, and spinal cord type may have cross-sectional myelitis.
Symptom
Cerebral paragonimiasis symptoms common symptoms abdominal pain hallucinations diarrhea calcifications paraplegia spinal cord compression
The first symptoms after infection with paragonimiasis are abdominal symptoms, such as abdominal pain, diarrhea, etc.; then pulmonary symptoms, lasting for the longest, coughing, rust-like sputum, chest pain, etc., brain lesions occur after 2 to 12 months The symptoms are very dangerous and need to be dealt with in time. Generally, they can be divided into two types: brain type and spinal type:
1. Brain type: The brain type patients in the epidemic area can be as much as 2% to 5%, especially in children and adolescents. It is often the case that a large number of cysts are swallowed once or in succession, and the worms in the brain are destroyed. The brain tissue forms cysts, and the worms can also swim and walk, causing multiple lesions, forming multiple cysts, such as invasion of the basal ganglia, internal capsule or thalamus and other parts, the consequences are more serious, due to the variable range of lesions, symptoms It is often seen that it affects the location of brain tissue and pathological changes. Headache, epilepsy and motor neurological disorders are common, and its clinical manifestations are as follows:
(1) symptoms of increased intracranial pressure, headache, vomiting, vision loss, optic disc edema, etc., more common in early patients.
(2) inflammatory symptoms, chills, fever, headache, meningeal irritation, etc., are also more common in the early days.
(3) irritative symptoms, epilepsy, headache, visual hallucinations, abnormal limbs, etc., mostly due to the lesion close to the cortex.
(4) brain tissue destruction symptoms, paralysis, feeling disappeared, aphasia, hemianopia, ataxia and so on.
These symptoms usually appear later, brain type patients in the process of healing can form calcifications in the brain, the discovery of cerebral calcification, combined with clinical and CT findings, help to locate the diagnosis, these patients are difficult to get from the sputum, feces The eggs were found in the gastric juice, but the immunological examination was still positive.
2. Spinal cord type: less common, mainly due to the invasion of the dura mater into the spinal canal to form an epidural or intradural cyst-like lesion, the lesions are mostly in the 10th thoracic vertebrae, clinically mainly the spinal cord compression site The following sensorimotor disorders, such as limb weakness, difficulty in movement, sensory defects (such as numbness in the limbs or numbness in the saddle area), also have low back pain, sciatica and incontinence or difficulty such as cross-sectional myelitis symptoms, and gradually Aggravated, and finally paraplegia occurred.
In the endemic areas, there are raw foods or half-food crabs, cockroaches, and people who have eaten raw water. They have coughs and rust-colored sputum in their medical history. Following unexplained headaches, vomiting, seizures and convulsions should be considered. may.
Examine
Examination of cerebral paragonimiasis
White blood cells and eosinophils often increase, in the acute phase, white blood cells can reach 40 × 109 / L (40,000 / mm3), eosinophils can be as high as 80%, sputum, feces and any body fluid and tissue biopsy specimens found in paragonimiasis Adults, larvae or eggs are the strong evidence for diagnosis. Eosinophils can be found in cerebrospinal fluid, protein content is increased, and eggs can be detected. In the stage of tissue destruction, bloody cerebrospinal fluid can still occur during cyst formation. Cerebrospinal fluid pressure is increased, protein is increased, and others are normal. This cerebral spinal fluid variability is one of the characteristics of this disease.
Immunological examination currently used in the skin test, enzyme-linked immunosorbent assay (ELISA), spot enzyme-linked immunosorbent assay, complement binding assay, etc., the positive rate can reach 98%, also has considerable specificity, There are different degrees of cross-reaction to schistosomiasis, clonorchiasis, ginger worm and other parasitic diseases. The complement fixation test of cerebrospinal fluid has a specific diagnostic value for this disease.
Cranial radiography, CT, cerebrovascular and myelography can detect lesions and obstruction. CT scan images show cerebral edema in the acute phase. The brain parenchyma can be seen in different sizes of low-density edema, varying degrees of cerebral ventricle. After the cystic period, there is a high-density space-occupying lesion, but the boundary is unclear, and the enhanced scan lesion is enhanced; the fibrous scar is characterized by calcification, and the M1-image shows a T1-weighted central high signal or the like. Signals, peripheral low-signal lesions, T2-weighted lesions showed low-signal lesions around the central high-signal. It has been reported in foreign countries that MRI is more likely to detect lesions in the cerebral hemispheres than CT.
Diagnosis
Diagnosis and diagnosis of cerebral paragonimiasis
Differential diagnosis:
1. Other cerebral parasitic diseases such as echinococcosis, cerebral cysticercosis, cerebral amoebiasis, and toxoplasmosis, mainly rely on epidemiological characteristics, specific immunodiagnosis and typical imaging examination the difference.
2. Non-parasitic infectious diseases of the brain such as encephalitis, brain abscess, brain tuberculosis, etc.
3. Non-infectious diseases of the brain such as cerebral infarction, cerebral vascular malformation, tuberous sclerosis and multiple sclerosis.
4. Brain tumors and brain metastases.
