Multilocular echinococcosis

　　First, Etiology

　　1. Morphology The multilocular echinococcus is slightly smaller than the small granular echinococcus. The adult worm is 1.3-3.0 mm long and 0.28-0.51 mm wide. There are four to five proglottids. The scolex has four suckers. There are two rings of small hooks on the rostellum, totaling 13-34 in number, of varying sizes. The ovary is divided into two lobes, located in the middle posterior half of the proglottid. The uterus is curved, ending in a pouch-like or spherical shape, without lateral branches, differing from the uterus in the gravid proglottid of the small granular echinococcus, which has 12-15 branches. The gravid proglottid uterus has no lateral pouches, containing eggs, averaging 300. The mature proglottids contain 26-36 testes, which is fewer than the number of testes in the small granular echinococcus (45-65). The reproductive openings are all on the lateral margin before the midline, mostly irregularly interlaced, and sometimes unilateral.

　　(1) Hydatid cysts: They are spherical, consisting of a cluster of small vesicles of varying sizes and shapes. The vesicle wall is divided into the inner germinal membrane and the outer homogeneous layer. The germinal membrane is rich in cells and has active proliferation, producing buds and protoscoleces. The homogeneous layer contains no cells and no keratin, thus differing from the cuticle layer of the small granular echinococcus. The cavity contains thick, gelatinous-like liquid and many protoscoleces. However, humans are not its suitable host, so the hydatid cyst cavities usually do not contain protoscoleces.

　　(2) Eggs: They are round or slightly elliptical, yellow, with a radially striated chorion, containing oncospheres, and are difficult to distinguish from eggs of other tapeworms.

　　2. Life cycle This worm has foxes, wild dogs, and wolves as definitive hosts in nature, while rodents such as field mice are intermediate hosts. The multilocular echinococcus lives in the small intestine of the definitive host, and gravid segments and eggs are excreted with feces. Rodents become infected by foraging on the feces of the definitive host. The scarab beetle can act as a vector for the eggs, and rodents can also become infected by eating scarab beetles. Humans can become infected by accidentally ingesting vegetables or untreated water containing eggs. The eggs hatch into oncospheres in the small intestine, which then invade the liver via hematogenous spread and develop into hydatid cysts. In areas where the disease is endemic, infected rodents are eaten by foxes or wild dogs, and the protoscoleces in the hydatid cyst cavities develop into adults in the small intestine of the definitive host.

　　Second, Pathogenesis

　　This pathogen primarily affects the liver, and can spread to the lungs, brain, and other organs through hematogenous and other pathways, causing secondary or metastatic lesions. The pathological changes in the liver can be divided into macrolithic, nodular, and mixed types, with the former being the most common. Macrolithic lesions appear pale yellow or grayish white, with an irregular surface. Many dense small vesicles can be seen, which are hard, without a capsule, and have unclear boundaries with the surrounding liver tissue. The cut surface often shows central necrosis, resembling the appearance of termite infestation, with an empty cavity inside. There are calcified foci in the worms, giving a gritty feeling when cut. The hydatid cyst is composed of countless small vesicles, with a large amount of fibrous tissue separating them, resembling a honeycomb. The cavity contains thick, jelly-like substances. The central part of the worm often undergoes ischemic necrosis, liquefies, and forms an empty cavity. The wall of the cavity is uneven, resembling stalactites or lava, with varying diameters, making it difficult to distinguish from liver cancer by naked eye.

　　显微镜下，在泡球蚴组织中可见无数密集小囊泡，大小形状不一。在人体病理标本中可见囊泡由生发膜与匀质层组成，但囊腔中原头节罕见。虫体周围有肉芽肿反应：纤维组织增生，嗜酸性粒细胞、淋巴细胞与浆细胞浸润，并常有异物巨细胞等，形成泡球蚴结节。

　　1、增殖方式泡球蚴以外殖性芽生繁殖为主，母囊的生发膜通过匀质层向外突出，芽生增生，产生新囊泡，即子囊泡与孙囊泡等无限制地增生，破坏肝实质。囊泡也可向囊腔内增生，呈棘状突出，延伸至囊泡对壁，形成隔膜性增生。

　　2、转移途径泡球蚴类似恶性肿瘤，可从肝脏转移或扩张至其他器官：(1)浸润性扩张：泡球蚴在肝内缓慢地无限制生长，可波及肝门，向上侵犯膈肌，破入胸腔，或向后侵犯下腔静脉。(2)血运播散：泡球蚴增生芽部分脱落后，经门静脉分支在肝实质内扩散，形成多发性结节，若侵入肝静脉分支，则随体循环血流播散至远处器官，其中以肺与脑居多。肺转移率约为20％，为双侧性，以右下肺为多。脑转移约占5％。(3)淋巴转移：至肝门与腹膜后淋巴结。

　　可并发门脉高压症，少数患者并发胸腔小量积液。门静脉高压症的形成是肝小叶内纤维组织增生和肝细胞再生，由于增生纤维索和再生肝细胞结节(假小叶)的挤压，使肝小叶内肝窦变窄或闭塞，以致门脉血不易流入肝小叶的中央静脉或小叶下静脉，血流淤滞，门脉压就增高。门脉高压症可引起侧支循环开放、脾肿大和脾功能亢进以及腹水等三大临床表现，其他尚有蜘蛛痣、肝掌和肝功能减退的表现。

　　潜伏期很长，从感染至发病一般在20年或以上，多房棘球蚴病病程长，具隐袭进行性特点，早期无临床症状，仅在肝脏B型超声波普查时发现。

　　1、肝多房棘球蚴病：患者就诊时主要症状为上腹隐痛或(与)肿块，根据临床表现可分为：

　　(1)单纯肝肿大型：临床症状视病变部位与大小而异，肝右叶顶部为好发部位，肝脏背后内侧向上肿大，抬高膈肌，有时肝脏肋下未能扪及，腹痛可放射至右肩背部，病变位于肝左叶者，病种早期即出现上腹肿块，易于发现，患者一般情况视病程长短，肝内病变范围大小而异，轻者一般情况尚好，重者肝脏整叶或两叶均有广泛病变，患者有乏力，消瘦等全身症状。

　　(2) Obstructive jaundice type: The hydatid lesion involves the porta hepatis, compressing the common bile duct to cause obstructive jaundice, which is progressive and often accompanied by skin itching, decreased appetite, and other gastrointestinal symptoms.

　　(3) Macrohepatic nodular type, or known as the hepatocellular carcinoma-like type, mainly manifested as an abdominal mass in the upper abdomen, locally prominent, with both liver lobes extremely enlarged, about 10 cm below the costal margin and xiphoid process, hard in texture, and multiple nodules of different sizes can be palpated on the surface. Liver ultrasound and CT scan show that most of the entire liver lobe is destroyed, while the other lobe shows significant compensatory enlargement, with a softer texture.

　　2. Pulmonary polycystic echinococcosis:Pulmonary lesions can be caused by the erosion of the right lobe of the liver across the diaphragm to the liver, or due to hematogenous metastasis. Clinical symptoms are mainly slight hemoptysis. Chest X-ray examination shows nodular lesions of different sizes in both lungs, 0.5-1.5 cm in size, more in the middle and lower parts, and a small number of patients have concurrent small amounts of pleural effusion.

　　3. Brain polycystic echinococcosis:The main clinical symptoms are focal epilepsy or hemiplegia, but they vary depending on the site of the lesion. Cranial CT scan shows honeycomb-like low-density foci in the temporal or (and) occipital lobes, and brain-type patients are all accompanied by obvious polycystic echinococcosis in the liver and lungs.

　　Mainly it is about food hygiene and strengthened management, educating residents in the epidemic area to avoid close contact with dogs and foxes, and doing personal protection when preparing fox skins. It is still not possible to control wild animals in nature.

　　1. Isolate as an infectious disease, eat semi-liquid or light food.

　　2. Avoid close contact with dogs, or regularly deworm domestic dogs and treat sick dogs.

　　3. Wash hands frequently, do not drink unboiled water, and do not eat raw vegetables.

　　4. Strengthen and popularize health education.

　　5. Implement registration management and strict control of stray dogs for domestic dogs.

　　6. Strictly manage the market and family slaughterhouses to prevent domestic dogs from contacting hydatid-infected organs.

　　Eosinophil count is slightly increased in blood, liver function tests are mostly normal, but in a few late-stage patients due to widespread liver lesions, serum alanine aminotransferase and alkaline phosphatase levels are elevated, albumin is decreased, globulin is increased, and the albumin/globulin ratio ≤ 1. The hydatid skin test is mostly positive, and most of the serum hydatid ELISA is positive in those with negative skin tests.

　　1. Liver ultrasound examination:All can show heterogeneous liver masses within, with disordered internal structure, irregular edges, and a necrotic liquefied dark area in the center of the mass. There are also punctate hyperechoic calcification foci.

　　2. Liver CT scan:Irregular and heterogeneous low-density areas can be seen, without clear boundaries. The center often has necrotic cavities and nodular calcification foci. The walls of large necrotic cavities are uneven, different from hydatid cysts, and are called pseudocystic hydatid disease.

　　First, food therapy recipe:

　　1. Loofah seeds Take an appropriate amount of black loofah seeds, peel and take the kernel, take with warm water on an empty stomach. 50 seeds each time, once a day. It can relieve roundworms. Indicated for ascariasis, abdominal pain around the umbilicus, intermittent pain, loss of appetite, yellowish and emaciated face, itching of the nostrils, and spots on the face.

　　2. Cabbage pepper powder 5 grams of carrot seeds, 5 grams of Sichuan pepper powder. Roast the carrot seeds slightly, grind into powder, mix with Sichuan pepper powder, and take on an empty stomach twice a day. It can invigorate the spleen and expel roundworms. Indicated for ascariasis, abdominal pain around the umbilicus, epigastric discomfort, nausea and vomiting, yellowish and emaciated face.

　　3. Peach leaf juice drink 60 leaves of fresh peach leaves. Clean the fresh peach leaves, crush them, and pour boiling water over them. Take the dregs together. It can relieve roundworms. Indicated for ascariasis, abdominal pain around the umbilicus in children, itching of the nostrils, poor appetite, dribbling of saliva during sleep, yellowish and emaciated face.

　　4. Pepper and mung bean powder 4 large grains of pepper, 4 large grains of mung bean. Grind into fine powder, take with wine. It can relieve roundworms and pain. Indicated for ascariasis, sudden onset of pain in the epigastrium and right rib, pain radiating to the back and right shoulder, and often accompanied by vomiting of roundworms, abdominal pain around the umbilicus at ordinary times, yellowish and emaciated face, and occasional itching of the nostrils.

　　5. Xiangfeizi 150 grams of Xiangfeizi. Roast the Xiangfeizi and chew it finely on an empty stomach in the morning. It can relieve roundworms. Indicated for ascariasis, pain around the umbilicus, intermittent pain, epigastric discomfort, yellowish and emaciated face.

　　6. Maimi decoction 10 grams of Sichuan pepper, 15 grams of black plum. Boil in water, take one dose twice a day, and take it in divided doses. It can relieve roundworms. Indicated for ascariasis, pain around the umbilicus, itching of the nostrils, dribbling of saliva during sleep, yellowish and emaciated face, or sudden severe pain in the epigastrium and right rib, nausea and vomiting, restless and uneasy.

　　7. Boil 250 grams of sesame straw, 50 grams of chive white, and 30 grams of black plum. Take the three ingredients in a decoction on an empty stomach, one dose twice a day, for 3 days. It can relieve roundworms. Indicated for ascariasis, frequent pain around the umbilicus, itching of the nostrils, dribbling of teeth during sleep, poor appetite, yellowish and emaciated face, nausea and vomiting.

　　Second, what should the patient eat less of?

　　1. Eat less food that is prone to produce gas, such as radish, sweet potato, beans, etc., and eat less oily foods.

　　What should the patient eat more of?

　　1. Drink more water, eat more foods rich in dietary fiber, such as grains, nuts, fresh vegetables and fruits, such as celery, chive, spinach, banana, peach, strawberry, etc.

　　The above information is for reference only, please consult a doctor for details.

　　First, traditional Chinese medicine treatment methods for multilocular echinococcosis

　　1. Hydatid disease affecting the liver

　　Symptoms manifestation: A painless mass in the upper right abdomen, firm and smooth to the touch, with a cystic sensation, accompanied by epigastric and abdominal fullness, oppression and pain under the right rib, possible ecchymosis on the edge of the tongue, white coating, and wiry and涩 pulse.

　　Indications and effects: Expel worms, soothe the liver, soften hardness and disperse nodules.

　　Prescription: Chaihu Shugan Powder. Add Leiwan, Bimiao, Tuber melo, fried Shanyao, etc.

　　2. Hydatid disease affecting the lung

　　Symptoms manifestation: dry cough in attacks, lasting for a long time without stopping, chest fullness and oppression, or sometimes coughing blood, shortness of breath, dry throat and dry mouth, chest X-ray examination shows circular or multi-circular lumps in the lungs with clear and smooth edges, red tongue with little coating, and thin and rapid pulse.

　　Function and indication: kill parasites, clear the lung, moisten the dryness, and relieve cough.

　　Prescription: Loubei Yangying Decoction plus Leiyao, Bimiao, Luhufang, etc.

　　3. Hydatid cyst affected by the lung

　　Symptom manifestation: severe headache, fixed and unchanging, prominent skull, vomiting continuously, or sudden fainting, tetanic convulsions, vomiting foam from the mouth, or paraplegia, pale tongue with white slippery fur, wiry and slippery pulse.

　　Function and indication: kill parasites, reverse, calm the wind, and resolve phlegm.

　　Prescription: Banxia Baizhu Tianma Decoction plus Huai Niuxi, Daidongshi, Leiyao, Bimiao, etc.

　　4. Antiparasitic and anti-itching method

　　Pinworm powder: Ruanzhong, Dahuang, in a ratio of 8:1, ground into fine powder, 1-1.5g each time, taken 3 times a day, before each meal, for 5-6 days, a course of treatment, can be used for 1-2 courses. If there is damp-heat in the lower burner, drugs such as Cangzhu, Huangbai, Kuxing, Bai Bu, and Difuzi can be taken internally.

　　Second, Western medical treatment methods for multilocular echinococcosis

　　Treatment mainly relies on surgery, so it is necessary to strive for early diagnosis and to perform surgery before the onset of compressive symptoms or complications. Many patients often miss the opportunity for radical surgery when they seek medical attention only after the onset of obvious symptoms such as cirrhosis, jaundice, and portal hypertension.

　　1. During the operation, the cyst fluid should first be aspirated with a fine needle, and care should be taken to prevent the leakage of the cyst fluid, and then the inner cyst should be removed. The inner cyst and the outer cyst have only slight adhesion, which is easy to peel off, and can often be removed intact. Before removing the hydatid cyst, 2% formaldehyde (formalin), 0.01% hydrogen peroxide, 1% iodine solution, 0.05% hypochlorous acid, or 25% glycerin can be injected into the cyst to kill the protoscoleces, and the efficacy of the latter four is better than that of formaldehyde, and the toxicity of hydrogen peroxide and glycerin is also low.

　　2. Use mebendazole (thiophanazole) 40-200mg/kg per day for a total of 16-48 weeks to treat echinococcosis, and all patients can tolerate it; but some people, after taking the drug for 3 months, still obtain positive results when the cyst fluid is taken for animal inoculation, so it is considered that the blood concentration of the drug after oral administration is low, and its efficacy is still difficult to determine, and it is currently only used as an auxiliary treatment for surgical therapy.

　　3. Albendazole (thiabendazole) has a high concentration in tissues and within the hydatid cyst, 10-40g/kg per day, taken orally in two doses, with a course of 30 days, and its efficacy is still satisfactory.