Cystic echinococcosis of the urinary and reproductive systems

　　1. Etiology

　　The Echinococcus granulosus parasitizes in the small intestine of dogs, and the eggs are excreted with feces, contaminating water sources, pastures, and other places. After humans accidentally ingest food contaminated with eggs, the eggs hatch into oncospheres in the duodenum. The oncospheres penetrate the intestinal mucosa, enter the capillaries, and enter the liver to develop into hydatids through the portal vein. If the oncospheres pass through the liver sinusoids, they can reach the lungs and develop into hydatids, so the incidence of liver and lung hydatid disease is relatively high. If there are still a few oncospheres passing through the pulmonary veins, they can reach the whole body through the systemic circulation, and all organs and tissues can be affected. The incidence of hydatid disease of the urogenital system in endemic areas accounts for about 2% to 5% of the total hydatid disease. The kidneys, bladder, spermatic cord, and testicles can all occur.

　　2. Pathogenesis

　　The oncosphere develops into an early hydatid cyst vesicle, gradually increases in size and forms an inner capsule with a germinal layer and a cuticle layer. The periphery of the hydatid is formed by the proliferative tissue of the intermediate host into a thick and tough fibrous tissue capsule, known as the outer capsule. The germinal layer of the inner capsule can produce a large number of germinal cysts, which fall into the cyst fluid and become daughter cysts. The daughter cysts can give rise to granddaughters. The germinal layer can also produce brood cysts, each containing 10 to 40 protoscoleces, which are free in the cyst fluid and called sand in the cyst. If the hydatid breaks or the operation is not careful, the sand can leak into the abdominal cavity and cause secondary hydatid disease.

　　1. Secondary infection due to a long history of hydatid disease, aging or degenerative changes in hydatids, malnutrition of hydatids; too many daughter cysts, insufficient cyst fluid, or due to hydatid rupture, etc., can cause secondary infection of hydatid cysts. At this time, the cyst fluid turns into purulent and forms acute renal abscess or encapsulated abscess in other tissues. If the inflammation is confined to the inside of the cyst by the fibrous tissue of the hydatid, the patient's systemic and local inflammatory reactions are relatively mild, and the main symptoms are general weakness, low fever, emaciation, anemia, and other chronic consumption manifestations. Severe infection can cause obvious systemic toxic reaction and local symptoms of acute abscess. The clinical manifestations of renal hydatid infection are similar to those of pyonephrosis or massive renal pelvis hydrops with infection, and attention should be paid to differentiation.

　　2. The hydatid cysts in the liver and other places can rupture due to trauma or puncture, and when they break into the abdominal cavity, they can cause severe abdominal pain and allergic symptoms. Due to the overflow of the cyst fluid, secondary hydatid cysts can be produced. If the cyst breaks into the intrahepatic bile duct, it can cause cholecystalgia and jaundice.

　　Cyst wall rupture can be caused by accidental trauma, infiltration of inflammation after infection, or misdiagnosis during diagnosis by puncture at the time of visit, and the clinical manifestations are very different depending on the degree of wall rupture and the location of the breach, mainly as follows.

　　If only the internal capsule ruptures, the overflowed fluid of the cyst is confined by the tough outer capsule, the internal capsule peels off and collapses, floating in the cyst fluid. At this time, due to the lack of nutritional supply to the hydatid, it undergoes denaturation and necrosis, eventually forming secondary infection.

　　If the outer cyst breaks, it can burst the inner cyst due to high intracystic pressure, causing the contents of the cyst to overflow into the surrounding tissues. Depending on the location of the cyst wall break, the path of cyst fluid overflow can be divided into three types:

　　(1) If the renal echinococcus breaks into the urinary tract, a large amount of cyst content enters rapidly, causing sudden renal colic and bladder irritation symptoms such as frequent urination, urgency, and dysuria. In severe cases, it can block the ureter, causing increased renal colic and radiation pain in the perineum. When the pressure in the proximal ureter increases to a certain level, these cyst contents can be excreted spontaneously. If the echinococcus breaks into the bladder, it can cause bladder irritation symptoms. At the same time, a large amount of visible white echinococcal cyst skin and small cysts are excreted.

　　(2) If the echinococcus breaks into the abdominal cavity, it can cause an acute generalized peritonitis. At the same time, due to the absorption of a large amount of heterologous proteins, anaphylactic shock may occur. Although timely antishock treatment and surgical treatment can temporarily save the patient's life by removing the cyst fluid in the abdominal cavity and removing the echinococcus, the disseminated implantation of the exogenous oncosphere in the abdominal cavity can cause hundreds of secondary multiple abdominal echinococcosis several months later, leading to widespread adhesions of abdominal organs and eventually leading to cachexia due to chronic consumption.

　　(3) If the echinococcus breaks into the extraperitoneal space, the cyst fluid can accumulate along the psoas muscle in the iliac region, forming secondary echinococcosis or secondary infection.

　　Living and historical records in areas with echinococcosis outbreaks, especially close contact with dogs and sheep.

　　1. The main symptoms of renal echinococcosis patients are renal mass, back pain, hematuria, and pyuria. It often occurs as a single mass in one kidney, and most often occurs at the lower pole of the kidney. It can occur with liver and lung echinococcosis. When the cyst breaks into the renal pelvis or calyx, the scurf-like substance containing cysts and inner layer fragments enters the urine, causing acute renal colic, frequent urination, urgency, and dysuria. Secondary infection can cause fever, increased back pain, hematuria, and pyuria. The rupture of the cyst into the peritoneal cavity can cause severe peritonitis.

　　2. Bladder echinococcosis mainly manifests as frequent urination, dysuria, urgency, cloudy urine, and the excretion of urine containing a scurf-like substance with cysts and inner layer fragments.

　　3. Patients with spermatic cord or testicular echinococcosis may have spherical masses locally, with positive transillumination test, similar to hydrocele.

　　The typical signs of echinococcal cysts are smooth surface during palpation, hardness and elasticity, and a tingling sensation when knocked. The renal echinococcus can be palpated as a smooth, well-defined, and painless mass in the upper abdomen or腰部.

　　The fundamental method for the prevention and treatment of echinococcosis is 'Prevention First', and publicity and education are the foundation for carrying out preventive work. The life cycle of the small grain echinococcus mainly occurs in the dog-sheep cycle chain. The detection rate of small grain echinococcus in sheep dogs in the epidemic areas is 30% to 60%, and the infection rate of echinococcosis in sheep flocks reaches 40% to 90%. Therefore, in epidemic areas, it is necessary to kill wild dogs, and for sheep dogs, the drug bait containing 50 to 100 mg of praziquantel should be administered according to the dog's weight once a month. This can cause death before the mature stage (40-50 days) of the small grain echinococcus, thereby eliminating the eggs of the intermediate host that cause infection.

　　Inspection and quarantine should be carried out for slaughtered sheep and beef, and the internal organs with water泡-like appearance should be buried deeply. It is absolutely forbidden to feed dogs to prevent the infection of the original head of the definitive host. Prevent the contamination of pastures and water sources by canine feces, do not drink unboiled water, wash hands before meals, clean the tableware, maintain personal and environmental hygiene, and persistently carry out scientific preventive work to achieve the goal of controlling the spread of echinococcosis in the population.

　　1. Blood test

　　Eosinophil count increases.

　　2. Urine examination

　　When the echinococcus breaks into the urinary tract, white powdery fragments can be seen in the urine, and the protoscoleces of echinococcus can be detected.

　　3. Serological tests

　　Tests such as indirect red blood cell agglutination test (IHA) and enzyme-linked immunosorbent assay (ELISA) are helpful for diagnosis.

　　4. Casoni intradermal test (ID)

　　It is a valuable diagnostic method. The method is to inject 0.1-0.2ml of specially processed cyst fluid into the antecubital skin, and observe the redness and induration of the skin reaction. The positive rate can reach about 90%, with high specificity and sensitivity of indirect red blood cell agglutination test, and few false positive reactions.

　　5. Ultrasound

　　Ultrasound can detect clear marginal anechoic areas, sometimes with petal-like septa or honeycomb-like light bands; sometimes, there may be a 'double-wall sign'. Bladder ultrasound examination shows a round anechoic liquid dark area with clear boundaries, rough cystic walls, and larger echinococcal cysts may show a 'double-wall sign'.

　　6. X-ray

　　KUB plain film shows enlargement of the renal shadow, with a mass outline protruding from the renal margin. Sometimes, there may be linear calcification shadows at the edge of the mass. Excretory and retrograde urinary tract imaging shows compression, deformation, and displacement of the renal pelvis and calyces, narrowing and elongation of the renal pelvis and calyces. When the cyst breaks into the renal pelvis, the contrast agent spills into the cyst, showing multiple circular filling defects. The contrast agent flows along the space between the daughter cysts, forming a rain-like sign. At the same time, hydronephrosis of the affected kidney may be seen, with poor or no contrast enhancement.

　　7. CT shows multiple cystic changes in the kidneys

　　The cyst wall is thick, with clear edges, and may have the 'cyst within a cyst' sign. Sometimes, there may be unique honeycomb-like separation images, which are helpful for diagnosis. If there are too many daughter cysts, they compress each other and are contained within the mother cyst, the CT shows a wheel-shaped or honeycomb-like arrangement of septa, which is a characteristic image of renal echinococcosis. Bladder CT shows a clear margin cystic mass on the bladder wall with uniform density. When containing daughter cysts, it presents as a 'cyst within a cyst' sign.

　　1. What foods are good for the body with urinary and reproductive system echinococcosis

　　Pay attention to nutritional intake in diet, eat more light foods such as vegetables and fruits, and supplement necessary vitamins and trace elements, such as eating more cucumbers, bitter melon, and purslane.

　　2. What foods should be avoided for urinary and reproductive system echinococcosis

　　Try to avoid drinking strong alcohol, eating spicy foods, and avoid fatty, fried, moldy, and preserved foods.

　　1. Drug treatment has been used in experimental research on the use of chemical drugs such as mebendazole (tetrachloromethazole), praziquantel, and albendazole (propylthiouracil) for the treatment of hydatid disease, which has achieved the effect of killing the protoscoleces and damaging the germinative layer of the hydatid cyst sac, but has not yet achieved the purpose of cure, so it can be used as a preventive measure for the recurrence of transplantation before and after surgery, and for the control treatment of disseminated multiple hydatid disease that cannot be cured by surgery.

　　2. Surgical excision is currently the only effective treatment method. Early detection and early surgery can perform partial nephrectomy or complete inner sac excision when the organ has not atrophied, thus avoiding total nephrectomy to preserve functional organ tissue. The surgical principle is to remove the hydatid cyst, prevent the leakage of cyst fluid to contaminate the peritoneal cavity, reduce the outer sac cavity, and prevent postoperative infection. There are three surgical methods:

　　(1) Total cystectomy: The outer sac of the hydatid cyst is a fibrous tissue formed by the hyperplasia of organ tissue, although it has no boundary line with the organ, it can still be stripped off or excised along the outer sac wall, or excised together with the diseased organ tissue. For large hydatid cysts with a long history, long-term compression of the organ tissue atrophy, losing function, it is advisable to perform complete excision of the hydatid cyst in the kidney or testicle.

　　(2) Complete excision of hydatid cyst: On the outer sac wall projecting from the surface of the organ, slowly and skillfully cut, gradually reaching the innermost layer of the outer sac wall, relying on the tension of the hydatid cyst itself, the remaining thin layer of the outer sac wall is ruptured, at this time, the hydatid cyst will automatically swell out from the rupture, and the rupture must be blocked with fingers to prevent the hydatid cyst from protruding to prevent explosion. Since the hydatid cyst wall is extremely fragile, it is forbidden to use sharp instruments to touch it, quickly cut the outer sac incision to one-third of the diameter of the hydatid cyst, and make a cruciate incision to enlarge the incision, lift the open outer sac, inject water and use fingers to separate the fibrous adhesions between the inner and outer sacs, and the hydatid cyst can slowly come out from the outer sac.

　　(3) Hydatid puncture excision: According to the 'tumor-free surgery' operation principle, first use gauze to protect the lesion, separating it from the surrounding abdominal organs, puncture and aspirate the cyst fluid with a three-way needle, inject 20% saline to dehydrate and destroy the protoscoleces, lift and cut open the outer sac, and remove the collapsed hydatid cyst and daughter cysts.

　　After the hydatid cyst is completely or punctured excised, an empty cavity occupied by the hydatid cyst remains in the kidney. The treatment method for this cavity is to clean the cavity sac wall, invert and suture to reduce the closure cavity, and for larger cavities, part of the outer sac wall can be cut off, sutured to close the cavity, and a closed tube for closed drainage can be placed.