What is Neurocysticercosis?

Cysticercosis is a zoonotic parasitic disease that seriously endangers people's health. It is distributed in 27 provinces (municipalities, autonomous regions) of China, with a high incidence in Northeast, North China, Northwest, and Southwest. There are about 2 to 3 million cysticercosis patients in the country. Cysticercosis is a disease caused by the larvae of Ascaris lumbricoides parasitizing human tissues such as the brain and eyes. Brain invasion is the most common. Others can invade subcutaneous tissues, muscles, and eyes. Ascariasis patients are the only source of infection, with a high incidence of young adults. Cysticercus can live for up to ten years, so early diagnosis, early treatment and reduction of complications are needed.

Basic Information

English name

cysticercosis

Visiting department

Infectious Diseases

Common causes

Larvae of pork tapeworms parasite human tissues

Common symptoms

Increased intracranial pressure, focal nerve signs, epilepsy, mental disorders

Contagious

Have

way for spreading

Contaminated food and self-infection

Causes of cysticercosis

Cases have been reported throughout China. The three provinces in Northeast China and Yunnan, Guizhou, Henan, Hubei, Shandong, and Anhui are more common and endemic. The infection rate is related to the habit of eating raw pork, and there are also reports of infections caused by sacral cercariae contaminated by cutting boards and knives. The age of onset is mostly young, and many children are infected.

Pork tsutsugamushi is the only source of infection for cysticercosis. The worm eggs excreted from the feces of the patient are infectious to himself and the surrounding people. Therefore, the human body is not only the ultimate host of Swine Ascaris, but also an intermediate host. After the worm eggs enter the human intestine through contaminated food and self-infection, the six-claw pupae inside the eggs come out of the shell, enter the bloodstream through the intestinal wall, and cysticercosis (cysticercosis) occurs in different parts of the human body. Among them, cerebral cysticercosis is the most common.

There are three types of infections in human cysticercosis: endogenous autoinfection: that is, pregnancy segments or eggs return to the stomach due to reverse peristalsis such as vomiting; exogenous autoinfection: that is, the worm that contaminates the feces of the patient's fingers Eggs, and then infect themselves orally; exogenous allogeneic infection: cysticercosis was acquired by eating vegetables, raw water, and food that contaminated eggs.

Clinical manifestations of cysticercosis

The incubation period is about 3 months. Clinical manifestations should vary depending on the number of cysticercus, parasitic sites, and human reactivity. Those with mild infections can be asymptomatic, only found during autopsy. There are three types of cysticercosis according to the parasitic site of cysticercosis, cysticercosis of the eye, cysticercosis of the eye, and cutaneous cysticercosis.

Cerebral cysticercosis

Due to the different numbers and locations of cysticeras invading the skull, as well as the different developmental processes and deaths of cysticercosis, the clinical symptoms are complex and changeable. In a few cases, due to a large number of cysticercosis entering the brain, the onset was rapid, obvious mental and neurological disorders appeared, and even rapid death. Generally speaking, the nerve damage of this disease depends on the mechanical effects caused by the number and location of cysticercosis and the inflammatory and toxic reactions caused by cysticercosis. It manifests as increased intracranial pressure, focal nerve signs, epilepsy, and mental disorders.
According to clinical characteristics can be divided into the following types:

(1) Meningoencephalitis type Diffuse cerebral edema and reactive inflammation changes caused by a large number of infections. Clinical manifestations include mental abnormalities, generalized epilepsy, paralysis, aphasia, sensory disturbances, meningeal irritation, ataxia, and coma, which cannot be explained by focal brain damage.

(2) Epileptic seizures include major, minor, psychomotor, or limited seizures. The same patient can have more than two forms of seizures, and they can be easily converted. Diversity and ease of conversion are characteristic of this type of cysticercosis.

(3) Brain tumor type manifested as increased intracranial pressure, epilepsy, forced head position, paralysis and sensory disturbance.

(4) Spinal cord cysts invade the spinal canal and produce signs of spinal cord compression, such as motor, sensory, and defecation disorders below the lesion level.

2. Subcutaneous tissue and muscle cysticercosis

Patients often have subcutaneous or intramuscular cysticercosis nodules, distributed on the head and trunk, fewer limbs, nodules are round or oval, 0.5 to 1.5 cm in diameter, solid, can be pushed freely under the skin or muscle, no tenderness. Nodules can appear or disappear on their own.

3. Cysticercosis

Early, I felt that there were oval black shadows floating, stretching and deforming, and creeping shadows. In the later stage, due to the disturbance of the internal tissues and the formation of inflammation, vision can be significantly reduced or even blind.

Cysticercosis test

1. Blood and cerebrospinal fluid examination

Peripheral blood can be seen to increase the eosinophil count, cerebrospinal fluid with eosinophils and abnormal lymphocytes is of reference value.

2. Cysticercus complement binding test

Positive. It is rarely used today.

3. stool test

Finding nodules or worm eggs in feces is of diagnostic significance.

4. Waist wear

The intracranial pressure can be increased, and the cerebrospinal fluid cell count and protein content can be increased.

5. Imaging examination

Including X-ray, B-ultrasound, CT and MRI examinations and ventricular angiography, especially the latter two are of great value in the diagnosis of cerebral cysticercosis. CT can diagnose most of the active, inactive and mixed phases of cysticercosis, and the diagnosis of calcification is better than MRI. CT can show various types of active and metamorphic deaths. But its resolution is not as good as that of MRI. If the cystic cyst and cephalosacral imaging are not satisfactory, a clear diagnosis of the disease can not be made during the active period or metamorphosis and death. Blind administration can induce cerebral edema, intracranial hypertension or shock. Cerebral cysticercosis is divided into four phases: active phase, metamorphic death phase, inactive phase and mixed phase. MRI is of great value in guiding clinical treatment.

6. Immunological examination

(1) Antibodies test Indirect hemagglutination test, enzyme-linked immunosorbent assay (ELISA), etc. are performed on antigens and patient serum or cerebrospinal fluid after purification of porcine cysticercus fluid. The detection of specific IgG antibodies has high specificity and sensitivity. Both clinical diagnosis and epidemiological investigation have practical value, but there are false positives and false negatives in the ELISA test, and there are cross-reactions with hydatid disease.

(2) Monoclonal antibody (McAb) method Detects cysticercosis circulating antigen to diagnose cerebral cysticercosis.

Cysticercosis test

Have a history of intestinal roundworm, or roundworm eggs or segments found in the stool. Three major symptoms of epilepsy, intracranial hypertension, and mental disorders, or accompanied by visual impairment and subcutaneous nodules. The diagnosis was confirmed by immunological examination combined with imaging examination.

Cysticercosis treatment

Pathogen treatment

The results of experiments and clinical studies prove that praziquantel and albendazole are the main drugs against cysticercus. They are suitable for active and partially degenerative deaths. ; Inactive and partly cysticercus do not require anti-worm treatment. Praziquantel is mainly insecticidal, with fast efficacy and short course of treatment, but with large side effects. Albendazole mainly affects the normal metabolism of the worm body, with a mild drug effect, a slightly longer course of treatment, and less side effects.
The experimental treatment of cysticercium with methoxypyridazole showed that the efficacy was significantly better than praziquantel and albendazole, and no obvious side effects were seen. Probably the most promising drug for the treatment of cysticercosis, which has yet to be expanded clinically.

Symptomatic treatment

For those with increased intracranial pressure, 250ml of 20% mannitol injection can be given intravenously and dexamethasone is added for 3 consecutive days before the pathogen treatment is started. Epilepsy and allergic reactions should be dealt with accordingly.

3. Surgical treatment

Intraocular cysticercosis is recommended for surgical removal. If treated with praziquantel, the worm can cause an inflammatory response after killing, and increase the attention or impaired vision. Intracerebral cysticercosis, especially the third and fourth ventricle cysticercosis are mostly single, which can also be removed by surgery.