埃及血吸虫病

　　一、发病原因

　　雄虫长10～15mm，宽0.8～1.0mm。体表有微小结节覆盖，口吸盘与腹吸盘各一。雄在腹吸盘后两侧体表折叠，形成抱雌沟。有4～5个睾丸。雌虫细长，20mm×0.25mm。子宫内含虫卵20～100个。产卵500～3000个/d。成熟虫卵淡棕黄色，卵壳透明，尾端有一终末小棘（尾棘）为特征，从尿与粪便排出时，内含活动毛蚴。

　　中间宿主螺蛳各地不同。非洲为小泡螺属（bulinus），如截形小泡螺（B.truncatus），球形小泡螺（B.globosus）等。印度孟买南部为一种狭窄铁色螺（Ferrisiatenuis）；葡萄牙、摩洛哥为梅提扁卷螺（planorbariusmetidjensis）。

　　尾蚴体部呈圆形，内有五对穿刺腺，尾蚴从螺体逸出后在水中自由流动，在水中最长可生活3天，但大多在24h以内死亡。当人与疫水接触，尾蚴脱去尾部，借穿刺腺分泌物的作用，从皮肤侵入。此后，童虫又侵入小静脉→右心→肺血管→肝脏，在肝内门静脉发育成长，约经20天后为性成熟成虫。雌雄虫合抱逆血流移行至肠系膜下静脉，有时停留在直肠静脉内，但大多数成虫通过痔静脉与阴部静脉至膀胱与盆腔静脉丛产卵。少数成虫也可在直肠与肠系膜下静脉内产卵。从尾蚴侵入至成虫产卵为10～12周。

　　Second, pathogenesis

　　The lesions of schistosomiasis in Egypt are mainly caused by egg granulomas, and adult worms rarely produce lesions. The degree of lesion depends on the number of worms infected in the body (worm burden). Schistosoma haematobium parasitizes in the bladder and pelvic venous plexus, and the eggs it produces mainly deposit in the submucosal and muscular layers of the bladder and distal ureter, especially in the bladder trigone. When the eggs break into the bladder cavity, they are excreted in urine, which can cause hematuria, but most of the eggs deposit in the bladder wall to produce granulomatous lesions. The bladder neck is also a common site of lesions. Normally, the muscle of the bladder trigone is directly downward from a horizontal position, joining to the acrosome to become the posterior wall of the urethra. When the muscle of the bladder trigone contracts, the urethra moves backward, causing the bladder neck to be completely open for urination. If the muscle in this area is damaged by egg granulomas, causing fibrosis and atrophy, it will lead to bladder neck achalasia and urinary dysfunction. Bladder neck obstruction and bladder wall lesions can cause bladder deformation, producing diverticula. In addition, bladder lesions can cause mucosal hyperplasia, forming polyps; finally, irreversible fibrosis and calcification occur. The ureter or bladder neck can cause renal pelvis hydrops, secondary bacterial infection, and finally lead to renal failure.

　　Genital organ lesions, male patients can cause prostatic and glans lesions; in female patients, the cervix, vagina, and labia can also be involved, but it is less common.

　　In addition to the urogenital system, eggs can pass through the inferior mesenteric vein to the appendix, cecum, colon, especially the rectum, to produce lesions. Eggs can be excreted in feces. A small number of eggs can enter the liver from the portal vein, causing tuberculous granulomas and periportal fibrosis.

　　Pulmonary lesions, the eggs of schistosomiasis in Egypt can pass through the vesical veins, via the inferior vena cava into the lungs. A large number of eggs repeatedly embolize the small pulmonary arteries, causing necrotizing obstructive endarteritis, leading to pulmonary circulation obstruction and pulmonary hypertension. According to the post-mortem results in Egypt, about 30% of patients have pulmonary artery lesions. Due to the damage to the vascular middle layer and pulmonary hypertension at the proximal end of the pulmonary circulation obstruction, the pulmonary artery often presents as a vascular tumor-like expansion. Since the blockage is before the pulmonary microvessels and not in the microvessels or alveoli, it does not cause hypoxia or cyanosis, nor is it accompanied by myocardial injury.

　　Male patients can cause prostatic and glans lesions; in female patients, the cervix, vagina, and labia can also be involved, but it is less common. Tuberculous granulomas and periportal fibrosis, pulmonary lesions. In the late stage, complications such as right heart failure may occur. If urinary tract infection is not treated thoroughly after the occurrence, the bacteria are not completely killed and the medication is stopped, the remaining bacteria may still be潜伏 there. Once they encounter fatigue or a decrease in body resistance, the remaining latent bacteria will again multiply and reproduce, which is another cause of recurrent urinary tract infection. Patients with urinary tract infection may also have congenital malformations, obstructions, calculi, etc., which are also important causes of recurrent urinary tract infection.

　　The incubation period ranges from 10 to 12 weeks from the invasion of the cercariae to the appearance of eggs in the urine.

　　1. Acute stage:In the areas where the disease is prevalent, most patients have recurrent infections, so acute stage symptoms are rare. Only a few patients have systemic symptoms such as fever, headache, and fatigue. Urticaria is common, and there may be abdominal pain and enlargement of the liver and spleen. The blood count shows a significant increase in eosinophils. The clinical manifestations are similar to those of acute Japanese schistosomiasis, but they are milder.

　　2. Chronic stage:Early symptoms are painless hematuria at the end of urination, which may last for several months or years without other symptoms. However, later, symptoms of chronic cystitis such as frequent urination and dysuria may gradually appear, leading to difficulty in urination, urinary tract obstruction, renal pelvis hydronephrosis, retrograde bacterial infection, and eventually leading to renal failure.

　　Cystoscopy can reveal sand spots (sandypatches) on the bladder wall formed by a large number of egg granulomas, proliferative inflammatory changes, and papillary growth, as well as stones composed of uric acid, oxalic acid, and phosphates. In Egypt, 83.1% of bladder cancer patients have schistosomal lesions, so schistosomiasis mansoni may induce carcinogenesis. These patients are generally younger, around 40 years old, and mostly squamous cell carcinoma that is completely differentiated; metastasis is rare and occurs late.

　　(1) Symptoms of the liver and intestines: They are much less frequent and severe than those of Japanese schistosomiasis, appearing later. They are mainly caused by granulomas around the colon and portal vein due to egg deposition. Eggs are excreted in the feces of patients with diarrhea and dysentery. Symptoms such as liver and spleen enlargement and liver fibrosis are generally mild.

　　(2) Symptoms of the respiratory system: They are relatively rare, with patients complaining of fatigue, dizziness, headache, palpitations, and pain in the anterior chest area. About 1/3 of patients may experience fainting after exertion. Chest X-ray examination shows significant expansion of the pulmonary artery, and electrocardiogram shows a tall P wave and hypertrophy of the right ventricle. In the late stage, right heart failure may occur due to obstructive pulmonary heart disease. Since there is no myocardial injury, it occurs relatively late. According to Egyptian reports, only 0.8% to 1% of patients develop pulmonary heart disease, and schistosomal pulmonary heart disease accounts for only 4% of the total number of heart disease patients.

　　(3) Symptoms of the reproductive system: Male patients may develop inflammation of the prostate due to egg deposition, leading to hardness. Sometimes, a large number of eggs can be found in seminal fluid. The eggs reach the spermatic cord veins via the mesenteric venous anastomoses, which can cause changes in the spermatic cord and epididymis. Due to the fibrosis of the tunica vaginalis, the lymphatic vessels of the scrotum become blocked, resulting in poor回流, which can cause the glans penis to appear like a skin tumor. The symptoms of female patients are generally less obvious, and there may be changes in the cervix, vagina, and labia, as well as rare inflammation of the fallopian tubes and uterus.

　　1. Source of infection: Patients are the source of infection. In addition, although macaques and chimpanzees have natural infections, they do not play a role in the transmission of the disease.

　　2. Modes of transmission: The eggs in the urine and feces of patients contaminate water sources such as rivers and ponds, where snails become infected and release cercariae. The latter mostly侵入the skin or mucous membranes. The mode of infection is essentially the same as that of Japanese and Manson schistosomiasis.

　　3. The susceptibility of the population is higher among farmers, with no difference between men and women. Women are susceptible to infection when washing clothes in the river, and children are susceptible when bathing or swimming. The infection rate is highest in the age group of 16 to 20 years old. In addition, in some endemic areas, water source pollution and contact with infectious water caused by religious and customs also increase the chance of infection.

　　1. Eosinophils are significantly increased in blood pictures, and the eggs with tail spines can be found in urine. After centrifuging the last few drops of urine, the eggs can be found by direct smearing. Urine sedimentation hatchery, in 10 minutes to 2 hours, the cercariae can be seen.

　　2. Direct tissue sampling from the bladder scope for histological examination, in which a large number of eggs can be found by the pressure film method.

　　I. Schistosomiasis dietary therapy

　　1. Acute schistosomiasis

　　For patients with liver and spleen damp-heat, 1500 grams of Strychnos nux-vomica, 100 grams of kernel of Junci, 300 grams of rhizome of Rubia cordifolia, 300 grams of Spatholobus suberectus, and 10 grams of realgar. The other four ingredients are ground into powder, the Spatholobus suberectus is decocted to make pills as large as pepper seeds, and beeswax is used as the coating. Take 20 grams a day, divided into two doses. This recipe has the effect of clearing heat, promoting diuresis, and detoxifying.

　　2. Early schistosomiasis

　　Pomegranate peel 9 grams, curcuma 3 grams, finely ground together. Take 10 water caltropes, decoct the juice for taking the medicine. This recipe has the effect of expelling worms, soothing the liver, and promoting diuresis.

　　3. Nausea and vomiting, dizziness in patients with schistosomiasis treated with antimonials

　　Prune 25 grams, licorice 10 grams, tangerine peel 20 grams. Add an appropriate amount of water, decoct and take the juice. This recipe has the effect of harmonizing the stomach and stopping vomiting.

　　4. Others

　　Red bean 30 grams, carp 1. Kill the carp, remove the gills, scales, and internal organs, cut into pieces, put into the pot, add washed red beans and other seasonings and water, boil, then simmer over medium heat until the fish is cooked. Do not add salt and drink the soup. This recipe has the effect of diuresis and detumescence.

　　II. What should schistosomiasis patients eat:

　　Pumpkin seeds

　　1. Function and indication:

　　Used for tapeworm disease and schistosomiasis.

　　2. Nutritional value:

　　The seeds of Luffa cylindrica, a vine of the Cucurbitaceae family. Luffa is also known as pumpkin, melon, or rice melon. It is cultivated in all parts of China. The mature fruits are harvested in summer and autumn, the seeds are collected after peeling the fruit, removing the flesh, and drying or roasting. The seed shell is usually removed before eating, and it is called pumpkin seed kernel.

　　3. Properties:

　　(1) Sweet in taste and neutral in nature. It can replenish the spleen and Qi, promote lactation, moisten the lungs, and expel worms.

　　(2) Contains abundant fatty acids (glycerides of linoleic acid, oleic acid, etc.), protein, carotene, vitamin B1, B2, C, cucurbita seed amino acid, and other components.

　　(3) Has a significant anthelmintic effect on tapeworms and roundworms, with paralytic effects on the middle and posterior segments of beef tapeworm or pork tapeworm. It can also inhibit and kill the larvae of Schistosoma japonicum in experimental mice, with a stronger effect on females. The effective ingredient of this anthelmintic is water-soluble cucurbita seed amino acid.

　　4. Uses:

　　Used for spleen deficiency and malnutrition, emaciation and weakness; spleen deficiency edema; postpartum insufficient lactation;百日咳, cough with dry throat; tapeworm, roundworm, and schistosomiasis.

　　5. Dosage:

　　Chew raw, eat fried, grind into powder, or decoct into a decoction.

　　Cucurbita seed can be used to treat schistosomiasis, but it must be taken in a large dose.

　　Diet should be easy to digest and rich in nutrition.

　　Third, what is bad for the body of female schistosomiasis patients:

　　Avoid spicy, greasy, hard and rough foods.

　　Medication treatment:

　　Praziquantel is a commonly used drug for treating schistosomiasis, effective against Schistosoma haematobium, Schistosoma japonicum, and Schistosoma mansoni. 40mg/kg, taken once or in two doses. Nifurtimox is effective against Schistosoma haematobium and Schistosoma mansoni. Dosage: 0.25mg/kg, taken in two doses, course of treatment: 7 days. However, Nifurtimox has many side effects, can cause psychiatric symptoms, and it is best to take diazepam 2.5mg, 3 times a day, to alleviate adverse reactions. Trichlorfon (Dichlorvos) is an organophosphorus preparation that has a cholinesterase inhibitory effect, which can paralyze Schistosoma haematobium. Dosage: 150-200mg, suppository, once a day, inserted 8-10cm into the rectum from the anus, lying in a head-down, buttocks-up position for half an hour, for 3 consecutive days; or oral, 5-15mg/kg body weight, once every 2 weeks, for a total of 2 times; or intramuscular injection, 100-150mg per day, course of treatment: 3 days. Surgical treatment: Ureterovesical anastomosis can be used to treat early ureteral wall stricture that has been narrowed again due to poor long-term efficacy after bladder scope dilation or ureteral orifice incision; if the middle segment below one ureter is too long and narrow, a segment of ileum can be used to replace one ureter and anastomose with the contralateral ureter; if both ureters are narrowed, a segment of ileum can be used to make a 'Y' shaped anastomosis to replace both ureters; if both ureters are obstructed and acute anuria occurs, emergency cystoscopy and ureteral catheter drainage should be performed; if catheterization fails, emergency nephrostomy drainage should be performed; if there is purulent kidney or renal dysfunction, renal nephrostomy drainage should be performed first for a period of time until renal function recovers, and then further treatment should be considered; if drainage does not help renal function recovery, renal resection should be considered again; excision of the contracted scar of the urethra can relieve the stricture of the bladder neck. Colpoplasty or ileocystoplasty can be used to treat contracted bladder. When bladder cancer occurs, radical cystectomy should be performed.