Schistosomiasis is a chronic disease caused by active activity in the human body of parasitic worms. Annually, treatment of this pathology is required for more than 200 million people.
general information
Schistosomiasis is a fairly serious disease provoked by blood flukes of the genus Schistosoma. During the period of introduction of parasites into the body, a person develops dermatitis, which is later complicated by fever, intoxication, damage to the intestine or the genitourinary system itself. The clinical picture in this case is due to the development of an immunoallergic reaction to flukes eggs.
Parasites penetrate the human body, usually during the most common agricultural or industrial activity as a result of contact with water contaminated by them. Adolescent and young children are most susceptible to the disease due to non-observance of basic rules of personal hygiene or bathing in dirty water. The World Health Organization is actively struggling with this problem by providing preventive treatment several times a year.
In total, two forms of schistosomiasis are distinguished: intestinal and urogenital. It is about the latter that we will discuss in more detail in this article.
What is genitourinary schistosomiasis?
This is a helminthic disease with a predominant lesion of the genitourinary system. This pathology is common in northern Africa, in Egypt, Saudi Arabia, Lebanon and Syria. In our country there are no proper environmental conditions for the functioning of schistosomes.
Infection occurs through direct contact with water, where these parasites live. After their introduction into the human body, an infected person gradually develops an allergic reaction in the form of itching, rash. During the migration of helminths throughout the body, general malaise, fever, and headache are noted. These signs are characterized by genitourinary schistosomiasis.
Causes
Symptoms of the disease appear immediately after the ingestion of the parasite Schistosoma haematobium. The length of the male body does not exceed 15 mm. Its front part has a cylindrical shape, there are many suction cups on it. The body length of a female can reach 20 mm.
The parasite penetrates the skin of people bathing / working in water. Also, cases of infection after drinking low-quality drinking water are known. Schistosoma haematobium rushes through the blood vessels and even the lymphatic organs to the organs of the small pelvis, where it lays eggs in the lumen of the veins. Further, they penetrate through the vascular wall into the membrane of the bladder, and in some cases into the genitals. From there, subsequently, together with urine, they are brought out. Scientists suggest that the eggs of these parasites can also be transmitted during sexual intercourse.
In residents of epidemically hazardous areas, these parasites can be found in the genitals. However, specialists in this field can not yet prove the existence of a connection between spontaneous abortion and helminth activity.
They can live from three and up to about 10 years in the body. Cases have been reported where parasite eggs were transmitted by contact by a person infected about 30 years ago.
Pathogenesis of the disease
Urogenital schistosomiasis is a very interesting disease that has always attracted the attention of scientists around the world. Infection occurs during direct contact of a person with water infected with parasites. The pathogenesis of this ailment is based on toxic-allergic reactions that occur as a result of the breakdown of helminths waste products. Edema develops in the skin around the places of introduction of the larvae, and so-called infiltrates, consisting mainly of leukocytes and lymphocytes, form during their migration.
The eggs of parasites “live” a certain cycle of their development in the body of mollusks to the stage of cercariae, which already enter the human body through the skin. Here they very quickly mature and turn into schistosomules. Then the parasites penetrate into the peripheral veins, where they gradually degenerate into mature individuals. Fertilized females go to the organs of the genitourinary system, lay their eggs here. Some of them are excreted together with urine and feces directly into the external environment.
Epidemiology
Genitourinary schistosomiasis is prevalent mainly in subtropical and tropical areas, deprived of high-quality water and proper sanitary conditions for living. According to experts, currently about 90% of people with this diagnosis are located on the African continent.
The disease usually affects poor rural communities. Women using contaminated water in their homework are also at risk. Urogenital schistosomiasis in children and adolescents in these regions is no exception. Due to inadequate hygiene and constant contact with contaminated water during bathing, they are especially at risk of getting sick.
The constant migration of the population and the movement of refugees contribute to the penetration of the disease into new areas. As people’s desire to explore unfamiliar countries increases, more and more tourists are diagnosed with the disease today.
Clinical picture
What are the signs of urogenital schistosomiasis (symptoms)? Both treatment and diagnosis of the disease are impossible without the presence of a characteristic clinical picture.
The incubation period averages from 10 to 12 weeks. At the time of penetration of the parasite through the skin, a person notes slight discomfort, as if injected with a needle. During the period of helminth migration, allergic reactions develop in the form of dermatitis with severe itching, rashes throughout the body. Symptoms of intoxication of the body also occur (headache, anorexia, increased sweating). In some cases, the liver and spleen increase in size. However, far from always such signs are accompanied by genitourinary schistosomiasis. Symptoms of the disease, or rather the degree of their severity, depend on the individual sensitivity of the person and the severity of invasion.
At the end of the acute and the beginning of the chronic stage of the pathology, hematuria often appears, which is accompanied by the release of blood during urination. Patients, as a rule, complain of general malaise, fever up to 37 degrees, pain in the area of the bladder. In addition, the liver and spleen increase even more in size. Such symptoms are associated with the introduction of parasites into the tissues of organs.
During the passage of eggs through the wall of the bubble, spot hemorrhages and hyperemia of the mucous membrane are possible. As a result of such mechanical damage, the infection often joins the pathological process, which entails the development of cystitis. Inflammation can spread up the ureters directly to the kidneys.
Urogenital schistosomiasis in the absence of timely treatment can go into the chronic stage. The defeat of the ureters is characterized by a decrease in their distal regions, which entails stagnation of urine, the formation of stones and the development of pyelonephritis. The late stage of the disease is characterized by the appearance of organ tissue fibrosis and its calcification. In this kind of situation, helminth eggs are calcified. The shape of the bladder changes, intravesical pressure rises. In especially serious cases, schistosomiasis can lead to disability and even premature death.
In men, the pathology is often accompanied by fibrosis of the seminiferous tubules, and in the fair sex - by multiple ulcerations of the vaginal mucosa.
Establishing diagnosis
Recognition of the urogenital schistosomiasis is carried out on the basis of clinical data (urticaria, weakness, general malaise, dysuric disorders).
According to experts, the most intensively parasite eggs are excreted in the urine around noon. However, to detect them, a daily dose of urine is usually examined. Initially it is defended in high banks, the packed liquid is then drained, and the precipitate itself is centrifuged. Then a microsporia sediment is carried out. Determination of the presence of larvae in the urine is carried out according to a similar scheme.
In some cases, the doctor may prescribe a biopsy of a piece of bladder mucosa. In addition, cystoscopy and radiography are used to assess the condition of the genitourinary tract. Such diagnostic measures can reveal thinning of blood vessels, deformation of the mouths of the ureters, polypous growths.
Essential therapy
Treatment and prevention of schistosomiasis are carried out exclusively in a hospital. Patients, as a rule, are recommended "Praziquantel" or "Azinox" in a daily dose of 40 mg / kg twice a day. The effectiveness of these funds, according to experts, is 80-95%. Important in the treatment of this pathology belongs to symptomatic therapy to improve the functioning of the affected systems of internal organs. In the event of a secondary infection, antibiotics are prescribed. In severe cirrhosis, polyposis, surgical intervention is recommended.
Note that Praziquantel is an effective and at the same time inexpensive drug that can defeat all schistosomatoses (bilharzioses). Treatment with this tool is also indicated for children and adolescents. Despite the fact that after a course of therapy there is a chance of re-infection, the risk of developing a severe form of the disease can still be reduced and even prevented.
The prognosis for using the above drugs is usually favorable.
Possible complications
An important condition for combating this pathology is timely treatment. Urogenital schistosomiasis otherwise threatens the development of very unpleasant complications. These include the following diseases: pyelonephritis, chronic renal failure. In addition, this pathology is considered a true precancer, since squamous bladder cancer often develops against the background of a chronic inflammatory process.
Preventative measures
How to prevent urinary schistosomiasis? Treatment, causes, symptoms of this disease are described above in this article. Below we list its main preventive measures.
- Timely identification and subsequent treatment in inpatient settings of patients.
- Prevention of penetration of schistosome eggs into water bodies.
- The destruction of mollusks through molluscocides.
- Use of special irrigation systems.
- Wear protective clothing during direct contact with contaminated water.
- Water treatment (filtration, boiling) before use.
- Settlement in reservoirs of predators that destroy mollusks.
- Centralized water supply to the regions.
- Active health education with the population living in the respective regions.
Particular attention is recommended to tourists who come from areas where urinary schistosomiasis is common. Symptoms of the disease should alert everyone. This is a clear reason to seek help from an appropriate specialist. Only in this way can the further spread of the infection be prevented and literally save a person's life.
WHO’s strategy to combat this disease is aimed primarily at reducing the incidence through periodic treatment with Praziquantel. This kind of therapy is intended for all people at risk (all those who live in endemic areas).
The frequency of such treatment depends solely on the prevalence of the infection. In areas with a high transmission of the disease, an annual repeat of the course of therapy is often required, and over several years.
The proposed treatment allows you to overcome schistosomiasis of the genitourinary system in the early stages and prevent its transformation into a chronic form in already infected people. Currently, the main obstacle to the implementation of the program described above is limited access to medicines, and more specifically to Praziquantel. According to available information, in 2012 it was received only by 14% of people who really need treatment.
Conclusion
This article provided information on the topic "Genitourinary schistosomiasis: causes, symptoms, diagnosis and treatment." WHO experts are actively working on the prevention of tropical diseases that have been forgotten by modern society, which include the pathology we described. Despite the diversity of such ailments, they have common features that allow them to persist in poverty.
Schistosomiasis is a fairly serious disease, which is diagnosed more and more every year. However, compliance with basic hygiene rules and timely treatment can forget about this problem forever.
We hope that all the information presented in this article will be really useful for you. Be healthy!