Paragonimiasis

Introduction to Paragonimiasis Paragonimus swiftum (paragonimiasiswestermani) is also known as paragonimiasis, caused by paragonimus westermani (paragonimus westermani), clinical features of cough, cough and rust, peripheral blood eosinophilia, parasitic parasites Corresponding symptoms can be produced in other areas. basic knowledge Sickness ratio: 0.001%-0.002% Susceptible people: no special people Mode of infection: fecal spread Complications: pleural effusion

The cause of Paragonimiasis

(1) Causes of the disease

The adult is male and female, the body is hypertrophic, the living body is often stretched and deformed, the specimen is oval after fixation, the ventral surface is flat, and the back is more convex; the body length is about 7~12mm, the width is 4~8mm; the body surface is covered with small spines; the front end has a mouth The suction cup has a abdominal suction cup in the middle of the ventral surface. The intestine is spirally curved. A lobulated ovary is juxtaposed with the uterus behind the abdominal suction cup. A pair of branched testicles are juxtaposed to the left and right, between the two intestines at the back of the body. The yolk gland is developed, both sides of the worm body, the eggs are golden yellow, elliptical, 80-180m long, 40~60m wide, the front end is slightly wider, there is a flat egg cover, the egg shell is uneven, and there is a blast cell in the egg. And more than 10 yolk cells.

The life history of Pneumocystis sinensis is parasitic in humans and dogs, cats, pigs and other livestock, and in the lungs of tigers, leopards, wolf foxes and other beasts. The eggs produced are smashed out and are the first intermediate host. The snails are swallowed into the body, and the scorpion scorpion, the female thunder, and the thunder are developed and propagated at various stages, producing a number of cercariae, which escape from the snail and invade the second intermediate host crab, and the muscles and internal organs of the scorpion. The formation of cystic mites, human and other animal raw or semi-raw foods containing cystic rock crabs, sputum or stream can be infected, sacs into the intestines, mites escape, swimming in the body, to the lungs and other internal organs and subcutaneous, After the muscles and other parts develop into adults, they lay eggs and form cysts (Fig. 1).

(two) pathogenesis

After the cystic scorpion of Paragonimus sinensis in the small intestine of the host, it can cause punctiform hemorrhage on the serosa when it passes through the intestinal wall. When it enters the abdominal cavity, it can cause fibrinous inflammation of the peritoneum. Patients may have abdominal pain and diarrhea at this time. When the child's liver passes through the diaphragm and enters the chest, it can cause pleurisy and adhesions. A small number of worms can enter the liver, causing damage to the liver. A few worms continue to mature and lay eggs in the abdominal cavity. Many cysts and egg nodules are formed on the surface of the abdominal organs and the ventral surface of the diaphragm.

When the child enters the lungs, it can cause damage and hemorrhage of the lung tissue. The lesions often appear in caves or tunnels. There are blood in them, and the worms and eggs are often seen. The surrounding inflammation is not obvious. Infiltrating shadows with blurred edges can be seen, and inflammatory exudation occurs near the necrotic area of the lesion, mainly acidic granulocytes, and there are many neutrophils and small round cells, and gradually form an acidic granulocyte abscess. The granulation tissue is formed to form a thin film-like abscess wall, and the contents gradually become a fluid red-brown liquid. Several abscesses are connected together due to the movement of the worm body, and communicate with each other. The cut surface is multi-atrial cyst-like, and is more under the X-ray. Atrial cystic shadow, after the abscess content gradually turned into a brown viscous semi-flowing liquid, a large number of Charcotic crystals and eggs were observed under the microscope, the wall of the capsule became thicker due to the proliferation of a large number of granulation tissue, and the nostrils were macroscopic. Or spherical sac, there is usually only one worm in the human sac, nodular shadow can be seen under the X-ray, and the egg granuloma is often seen around the wall. When the worm is dead or metastasized, the contents of the abscess By It is absorbed and replaced with granulation tissue, and finally forms a scar or calcification. Under the X-ray, it is an induration or calcification shadow. The worm can also move from the lung tissue to the mediastinum, and move up along the root of the large blood vessel, along the internal carotid artery. The soft tissue passes up to the bottom of the skull, enters the cranial cavity and brain through the ruptured hole or jugular vein hole, and the worm body travels through the brain to form a cyst that communicates with each other. Adults and eggs can be found in the brain.

Wei's paragonimiasis prevention

The key to preventing this disease is to eliminate raw habits such as raw food, half-life crabs, sputum and drinking raw water, thoroughly treat patients and sick animals, kill the main pests that are harmful to humans, change spitting and bowel habits, and raise Domestic ducks or breeding squid to eliminate the first intermediate host can cut off the relay route.

Wei's paragonimiasi complication Complications pleural effusion

Complications are common secondary infections, with pleural effusion.

Symptoms of Paragonimiasis Common Symptoms Abdominal Pain Diarrhea Difficulty Abdominal Tumors Weakness Night Sweat Pain Appetite Lack of Hematopoietic Pleural Adhesion

The incubation period varies from 2 to 15 days in the short and 1 to 3 months in the elderly. The disease is divided into acute and chronic phases.

1. In the acute phase, due to the entrance of the capsule to the intestine, through the action of the digestive juice, the aphid is released from the sac, penetrates the intestinal wall into the abdominal cavity, develops into the larva and moves away in the abdominal cavity, causing peritonitis and adhesion, 1~ Within 3 weeks, most of the worms passed through the chest, producing pleurisy, and finally entering the lungs, forming cysts, and developing into adults to lay eggs. Patients often develop chills, fever, and relaxation heat within 1 week of infection. Abdominal pain, diarrhea, sauce color stool, fatigue, night sweats, lack of appetite, chest pain, cough, asthma and other chest symptoms after 2 to 3 weeks, in addition, there may be urticaria, total white blood cells and eosinophilia.

2. Chronic period The typical symptoms of this period are cough, hemoptysis and phlegm, often jam-like or rotten peach-like. Chaco-Leiden crystals and a large number of eggs can often be found in the sputum. According to the main lesions and the location of the symptoms, the following type:

(1) Pulmonary type: The main lesions in the lungs are abscesses and cysts, mostly located in the transverse plane, the mediastinum or the shallow tissues of the lungs. The small cysts are rice grains, and the larger ones are 2 cm in diameter, among which the eggs can be found. Insects or adults, the typical clinical symptoms are cough, phlegm and blood stasis, often rust-like, jam-like or rotten peach-like, when the chest pain occurs, mostly in the intercondy or lower chest, a few may have difficulty breathing, asthma or pleural effusion, Signs are not obvious, chest X-ray examination can be seen in the early stage, the edge is blurred, the density is deepened by circular infiltrative shadow; the middle can be seen sharply rounded or oval, single or multi-room, cystic or substantial, varying in size Shadow; in the late stage, punctate or cord-like dense shadows of varying sizes, pleural adhesions and thickening, and pulmonary symptoms often coexist with other types.

(2) Abdominal type: When cysticercosis moves in the abdominal cavity, it can cause extensive inflammatory reaction and adhesion, and form cysts, scattered throughout or aggregated, making the surface of the peritoneum rough, colon and small intestine serosa congestion, dirty There are different degrees of adhesion between the device and the tissue, and there is little ascites. Clinically, there may be abdominal pain, diarrhea, vomiting, blood in the stool, occasional severe abdominal pain such as acute abdomen, and the abdomen may sometimes touch the nodules and masses.

(3) Intestinal type: mainly abdominal pain, diarrhea, mucus and bloody stools, and eggs can be found in the stool.

(4) Brain type: the brain lesions are mostly in the temporal lobe and occipital lobe, and can also affect the white matter and the inner capsule, the basal part and the lateral ventricle, which are more common on the right side. Local cysts can block the ventricle passage and form atrophy or enlargement of the ventricles. The optic nerve is compressed, etc., a large number of eggs are visible in the capsule, and sometimes the worm body is visible. The spinal cord lesion is more common in the plane below the 10th thoracic vertebrae, which may cause changes in the lesion due to the walking of the worm body, and clinically has a paroxysmal or persistent headache. Vomiting, epilepsy, aphasia, visual impairment, neck stiffness, Kelnigue's sign and Bruzinski's sign can be positive.

(5) Spinal cord type: mainly caused by spinal cord compression symptoms such as abnormal limbs and trunk, dyskinesia, paralysis, difficulty in urinating and defecation.

(6) Nodular type: Sometimes the child worm penetrates into the muscle and subcutaneous, develops into an adult, forms subcutaneous nodules and masses, and the mirror is a typical eosinophilic granuloma with a gray-yellow necrotic tissue in the center, including Charcot-Leiden. Crystals, can be found in eggs, children or adults, with subcutaneous and muscular nodules as the main performance, the following between the abdomen to the thigh, followed by the back, buttocks, perineum, etc., deep position, diameter 1.2cm Single or several connected, the quality is tough, can move, slightly tender, after the worm leaves, the nodular inflammation subsides, leaving a small fiber block.

The clinical features of this issue: migration, due to the worms or adults, often the old lesions disappear, new lesions appear, resulting in various symptoms, signs one after another, haunting, changeable, systemic symptoms are not obvious, most patients have normal diet Early common white blood cells and eosinophilia, brain and spinal cord type patients often have increased intracranial pressure during the acute phase of activity, a slight increase in the number of cells, and eosinophils, mild or moderate increase in protein, such as chronic patients The lesion is inactive, the cerebrospinal fluid is normal, and the complement fixation test is often positive.

Inspection of Paragonimiasis

1. Check the eggs, check the eggs in the feces and various body fluids, or see the eggs or worms in the subcutaneous nodule biopsy.

2. Immunological diagnosis

(1) Intradermal test: intradermal injection of 1:2000 paragonimiasi antigen 0.1ml forearm, 15~20min, pimple 12mm, blush 25mm is a positive reaction, can be used for screening examination.

(2) Complement binding test: The positive rate can reach 100%, but it has cross-reaction with the serum of clonorchiasis and leprosy patients. When the cerebrospinal fluid of patients with brain paragonimiasis is positive, it has specific diagnostic value.

(3) enzyme-linked immunosorbent assay: high sensitivity, high specificity, in addition, indirect red blood cell agglutination test, agar two-way diffusion, convective immunoelectrophoresis, immunofluorescence, radioimmunoassay, etc., can detect specific antibodies in serum.

(4) Spot-enzyme-linked immunosorbent assay (Dot-ELISA): This method was established in recent years to detect the corresponding antigen in the serum of a patient with a specific monoclonal antibody against Paragonimus, which has good characteristics and sensitivity.

Pulmonary and pleural lesions can be performed by chest X-ray examination. It is also helpful for cranial-type patients to have cranial radiographs, CT, MRI, and EEG.

Diagnosis and identification of Paragonimiasis

Diagnostic criteria

1. Clinically diagnosed patients who have lived in epidemic areas, have had a history of raw or semi-food crabs, crickets, shrimps or streams, and have one of the following clinical manifestations, should consider the possibility of this disease and conduct further examination.

(1) hemoptysis or jam-like sputum.

(2) Abdominal pain of unknown cause, abdominal mass, subcutaneous nodules, which have the characteristics of one after another.

(3) Unexplained headaches, hemianopia, hemiplegia, subarachnoid hemorrhage and other neurological symptoms, and the symptoms are variable.

(4) persistent eosinophilia.

(5) The chest radiograph has a single- or multi-room cystic shadow of broad bean.

2. Laboratory diagnosis

(1) Egg inspection: , feces and various body fluids to see the eggs, or subcutaneous nodule biopsy see eggs or worms, you can confirm the diagnosis.

(2) Immunological diagnosis:

1 Intradermal test: intradermal injection of 1:2000 paragonimitic antigen 0.1ml forearm, 15 ~ 20min, pimple 12mm, blush 25mm is a positive reaction, can be used for screening examination.

2 Complement binding test: The positive rate can reach 100%, but it has cross-reaction with the serum of clonorchiasis and leprosy patients. When the cerebrospinal fluid of patients with brain paragonimiasis is positive, it has specific diagnostic value.

3 enzyme-linked immunosorbent assay: high sensitivity, high specificity, in addition, indirect red blood cell agglutination test, agar two-way diffusion, convective immunoelectrophoresis, immunofluorescence, radioimmunoassay, etc., can detect specific antibodies in serum.

4 Spot-Enzyme-Linked Immunosorbent Assay (Dot-ELISA): This method has been established in recent years to detect the corresponding antigen in the serum of a patient with a specific monoclonal antibody against Paragonimus, which has good characteristics and sensitivity.

5 Other tests: Chest X-ray examination of lung and pleural lesions, cranial imaging of cerebrospinal patients, CT, MRI, EEG, etc. are also helpful.

Differential diagnosis

Pneumococcosis must be differentiated from tuberculosis, bronchiectasis, bronchitis and lung tumors; spinal cord trematode must be differentiated from spinal cord tumors, multiple radiculitis, poliomyelitis, syringomyelia; cerebral paragonimiasis must Encephalitis, tuberculous meningitis, primary epilepsy, identification of cerebral cysticercosis; intestinal and abdominal paragonimiasis with dysentery, tuberculous peritonitis, intra-abdominal tumor, chronic colitis and other causes of intestinal adhesions, intestinal obstruction Identification.

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