multilocular echinococcosis
Introduction
Introduction to multi-room hydatid disease Echinococcosis multilocularis is a disease caused by the parasitic human body of the larvae of the Echinococcus multilocularis, also known as alveolarechinococcosis (Ae), multi-atrial bag In the aspects of biology, epidemiology, pathology and clinical manifestations, both vesicular and cystic echinococcosis are significantly different. basic knowledge The proportion of illness: 0.003% Susceptible people: no special people Mode of infection: digestive tract spread Complications: portal hypertension, pleural effusion
Cause
Causes of echinococcosis
(1) Causes of the disease
1. Morphology: Aphis gossypii is slightly smaller than A. granulosus, adult is 1.3 to 3.0 mm long, 0.28 to 0.51 mm wide, and there are four or five segments. There are four suction cups on the head and two on the top. Small hooks, 13 to 34 in total, varying in size, ovary is divided into 2 leaves, located in the middle of the posterior segment of the segment, the uterus is curved, the end is inflated into a bag shape, or spherical, regardless of the lateral branch, and the echinococcosis There are 12 to 15 branches in the uterus. There are no lateral sacs in the uterus, and there are 300 eggs in the uterus. The number of testes in the mature segment is 26 to 36, which is the number of testes of the echinococcosis. ~65) Less, the genital holes are in the side edge of the front line, mostly irregular staggered openings, and one side opening is also visible.
(1) Bubble sputum: It is a spherical vesicle, which is a small vesicle that aggregates into different groups. The size and shape are different. The wall of the capsule is divided into the inner layer of the hair growth membrane and the outer layer. The hair growth membrane is rich in cells and the proliferation is active. Produces germ and original ganglion, no cells in the homogenous layer, no keratin, so unlike the cortex of the granules of the granules, the sac cavity contains a viscous gelatinous liquid, and there are many original horns, but the human It is not suitable for the host, so the balloon sac cavity usually does not contain the original head.
(2) Eggs: round or slightly elliptical, yellow, the embryonic membrane is radial stripes, contains six hooks, and is difficult to identify with other aphid eggs.
2. Life history: In the natural world, the fox, the wild dog, the wolf, etc. are the final hosts, and the rodents such as the voles, which are preyed by them, are intermediate hosts, and the echinococcosis is parasitic in the terminal small intestine, the gestation and the worm. The eggs are excreted in the feces, the rodents are infected by feeding the host feces, the ground beetles can act as transporting eggs, and the rodents can also be infected by the predatory beetles. People are eating vegetables or raw water containing eggs. Infected, the eggs in the small intestine hatch six hooks, the latter invaded the liver through blood, developed into a bulbous sputum, in the epidemic area of the disease, infected rodents are preyed by foxes or wild dogs, bubble bulbs The protoplast in the cavity develops into an adult in the small intestine.
(two) pathogenesis
The primary disease of the disease is located in the liver and can be disseminated to the lungs through blood transport, etc. The brain and other organs produce secondary or metastatic lesions. The pathological changes of the liver can be divided into giant type, nodular type and mixed type. The former is Main, giant lesions are pale yellow or grayish white, the surface is not flat, many dense small vesicles are visible, hard and non-enveloped, and the boundary with the surrounding liver tissue is unclear. The cut surface often shows central necrosis, which is worm-like. There are cavities, there are calcifications in the worms, so there is a sand-like sensation when the knife is cut. The globules are composed of numerous small vesicles. There are a lot of fibrous tissue spaces between the vesicles, which are like honeycombs. The capsules contain sticky gelatinous substances. The center of the worm body is often due to ischemic necrosis, disintegration and liquefaction, forming a cavity, and the wall of the cavity is uneven. It is like a stalactite or lava. The diameter of the cavity is different. It is difficult to distinguish it from liver cancer by the naked eye.
Under the microscope, numerous dense small vesicles can be seen in the spheroidal tissue, and the size and shape are different. In the human pathological specimen, the vesicles are composed of the hair growth membrane and the homogenous layer, but the original anterior segment is rare in the cystic cavity. Granuloma reaction: fibrous tissue hyperplasia, eosinophils, lymphocytes and plasma cells infiltration, and often foreign bodies giant cells, etc., forming a bulbous nodules.
1. Proliferation mode: the bulbous buds are mainly germinated and propagated, and the growth membrane of the mother sac protrudes outward through the homogenous layer, and the buds proliferate, producing new vesicles, that is, the vesicles and the vesicles and other unrestricted proliferation. Destroy the liver parenchyma, the vesicles can also proliferate into the cystic cavity, protruding in a spinous manner, extending to the vesicles against the wall, forming a diaphragm hyperplasia.
2. Metastatic route: A bulbous sputum resembles a malignant tumor and can be transferred or expanded from the liver to other organs:
(1) Invasive dilation: The bulbous sputum slowly grows unrestrictedly in the liver, can spread to the hepatic hilum, invade the diaphragm, break into the chest, or invade the inferior vena cava.
(2) Blood transport: After the buds of the bulbs are partially detached, the branches of the portal vein spread in the liver parenchyma to form multiple nodules. If the branches of the hepatic veins invade, the blood flows to the distant organs with the circulation of the body. Among them, lung and brain are mostly, the lung metastasis rate is about 20%, which is bilateral, with more right lower lung and brain metastasis accounting for 5%.
(3) Lymphatic metastasis: to the hilar and retroperitoneal lymph nodes.
Prevention
Multi-room hydatidosis prevention
(1) Strengthen health publicity and education so that the masses can understand and understand the hazards and prevention methods of multi-room hydatid disease. The epidemic area should conduct a general survey of the population, and use immunological tests and X-ray and B-ultrasound to find patients early so that they can be cured in time.
(2) Personal protection for the fox fur is not possible to control the wildlife in nature.
(3) Eliminating foxes and eradicating voles are the main measures to eradicate the source of infection. In the implementation, attention should be paid to burning or deep burying animal corpses. Wild dogs should also be killed or controlled. For domestic dogs, they should be dewormed regularly.
Same as cystic echinococcosis, mainly food hygiene and enhanced management. Residents in educational epidemic areas avoid close contact with dogs and foxes, and personal protection when fox skin is stripped. The control of wild animals in nature is still not realized.
Complication
Multi-room echinococcosis complications Complications , portal hypertension, pleural effusion
Can be complicated by portal hypertension, a small number of patients with a small amount of pleural effusion.
Symptom
Symptoms of multiple echinococcosis common symptoms abdominal mass loss, fatigue, abdominal pain, liver enlargement, jaundice, hemoptysis
The incubation period is very long. From infection to onset, it is generally 20 years or more. The disease course of multi-room hydatid disease is long, with invasive progressive characteristics. There is no clinical symptom in the early stage. It is only found in the liver B-type ultrasound screening.
1. Liver multi-room hydatidosis: The main symptoms of patients at the time of treatment are upper abdominal pain or (and) mass, which can be divided according to clinical manifestations:
(1) Simple hepatomegaly: The clinical symptoms vary depending on the size of the lesion and the size of the lesion. The top of the right lobe of the liver is a good site. The posterior medial side of the liver is swollen upwards, raising the diaphragm, sometimes the liver is not ribbed, and the abdominal pain can be radiated. To the right shoulder and back, the lesion is located in the left lobe of the liver. The upper part of the disease appears as an upper abdominal mass, which is easy to find. The general condition of the patient depends on the length of the disease. The extent of the intrahepatic lesion varies, and the light is generally good. Or both leaves have extensive lesions, and the patient has systemic symptoms such as fatigue and weight loss.
(2) obstructive jaundice type: bulbar sputum lesions involving the hepatic hilum, compression of the common bile duct caused by obstructive jaundice, jaundice is progressive, often accompanied by skin itching, loss of appetite and other gastrointestinal symptoms.
(3) Giant liver nodular type, or liver-like type, mainly manifested as upper abdominal mass, local uplift, extreme left and right lobe of the liver, respectively, under the assist margin and about 10cm under the xiphoid, hard, surface It can be used to treat multiple nodules of different sizes. The liver B-ultrasound and CT scan showed that most of the whole liver was destroyed, while the other leaf showed a significant compensatory increase, and the latter was soft.
2. Lung multi-room hydatidosis: lung lesions can be eroded by the right lobe lesions to the liver, or caused by blood transfer, clinical symptoms are mainly small hemoptysis, chest X-ray examination shows the size of both lungs Not limited to nodular lesions, 0.5 ~ 1.5cm size, more in the middle and lower part, a small number of patients with a small amount of pleural effusion.
3. Cerebral echinococcosis: The main clinical symptoms are localized epilepsy or hemiplegia, but depending on the lesion, CT scan of the brain can be seen in the temporal lobe or (and) occipital honeycomb low-density lesions, brain-type patients Accompanied by obvious liver and lung multi-room hydatidosis.
Examine
Multi-room hydatid disease examination
Eosinophils in blood are slightly increased, liver function tests are mostly normal, only a small number of patients with advanced liver disease, serum alanine aminotransferase and alkaline phosphatase increase, albumin decreased, globulin increased, white / globulin The ratio is 1.
Most of the hydatid skin tests were positive, and a few skin tests were negative. Most of the serum hydatid ELISAs were positive.
1. Liver B-ultrasound examination: Both can show uneven hepatic mass, internal structure disorder, irregular edge, necrotic liquefaction dark center in the center of the mass, and spotted strong echo calcification.
2. Liver CT scan: visible irregularly low density area with irregular contours, no obvious boundary, common necrotic cavity and plexus calcification in the center, large necrotic cavity wall is uneven, different from hydatid cyst It is a pseudocystic echinococcosis.
Diagnosis
Diagnosis and diagnosis of multiple echinococcosis
Diagnostic criteria
1 Epidemiological history: The patient is from a prevalent area, or has lived in an epidemic area for a long time, has a close contact with dogs, foxes, etc., or a hunting hunter who kills foxes and strips their fur.
2 clinical symptoms: liver enlargement and pain: the abdomen has a lump, hard, surface nodules, B-ultrasound or CT examination of the boundary of the unclear substantial lesions, has important reference value for diagnosis.
3 Immunological test: Most of the hydatid skin test is positive, and often strong positive reaction; occasionally negative skin test, serum ELISA and Em2 antigen and Eml8 antigen detection of blood antibody test, its specificity and sensitivity are higher With less cross-reaction, it can be used to identify vesicular and cystic echinococcosis.
Differential diagnosis
Multi-room hydatidosis needs to be identified with the following conditions:
1 primary liver cancer: Hepatic multi-room hydatid disease is often misdiagnosed as liver cancer in non-endemic areas, even in the case of surgical exploration, it is difficult to identify by naked eye, the primary liver cancer has a short course, the disease deteriorates quickly, serum The alpha-fetoprotein test is positive, the diagnosis of hepatic polyhepatic hydatidosis is very important, and the epidemiological history is very important. The intradermal test of the hydatid is simple and easy. Combined with the characteristics of B-ultrasound and CT scan imaging, it can be identified.
2 Echinococcus granulosus: In some endemic areas in China, such as Ganzi Autonomous Prefecture, Sichuan, there is a mixture of cystic and multi-room hydatidosis. The symptoms of echinococcosis are painless lumps in the abdomen. Most patients with rickets have abdominal pain, liver is hard, the surface is uneven, there are nodules, B-ultrasound and CT images are significantly different, easy to distinguish.
