Intestinal worms is a helminthic disease caused by helminths – round and flat, less often annular and spiny-headed parasitic worms. Disease is characterized by a chronic course and systemic effects on the body with the development of abdominal, allergic, anemic syndromes, chronic toxicosis; lesions of the lungs, liver, biliary tract, brain, organ of vision. Laboratory (helminthoscopic, helmintholarvoscopic, serological) and instrumental (X-ray, endoscopy, ultrasound, etc.) methods are used in the diagnosis of intestinal worms. Treatment depends on the type of parasite and includes specific (anthelmintic) and pathogenetic therapy.
ICD 10
B65-B83 Intestinal worms
General information
Intestinal worms – helminthic infestations caused by various types of lower parasitic worms – helminths. Intestinal worms has a chronic course, accompanied by depletion of the body and a decrease in its natural defenses. In the structure of intestinal worms, the leading places belong to enterobiosis, ascariasis, hookworm, trichocephalosis and toxocarosis.
According to official statistics, the infestation of the USA population with intestinal worms is 1-2%, but in some regions it reaches 10% or more. The problem of the increase in the incidence is relevant not only for infectious diseases, but also for pediatrics, therapy, surgery, gastroenterology, urology and other practical medical areas.
Causes
To date, more than 250 pathogens of intestinal worms in humans are known; about 50 species of them are most common. Parasitic helminths in the human body are mainly represented by roundworms (Nematoda class) and flatworms (fluke class – Trematoda and tapeworms – Cestoidea); less often, human infection occurs with annelid worms (Annelida) and scrapers (Acanthocephala). Representatives of roundworms include pinworms, ascarids, trichinella, whipworm; tapeworms – bovine, pig and dwarf tapeworms, echinococci, broad tapeworm; suckers are feline and liver flukes.
The life cycle of helminths includes the stages of eggs, larval and sexually mature forms. Depending on the features of the development of parasitic worms and ways of infection, helminthic diseases are divided into biohelminthiasis, geohelminthiasis and contagious (contact) intestinal worms.
- Geohelminths are the majority of roundworms (nematodes). The stages of development of eggs and larvae of geohelminths take place in the soil under certain temperature and humidity conditions. Infection with geohelminthiasis occurs when personal hygiene is not observed, eating water contaminated with parasites, fruits, vegetables or contact with soil contaminated with feces. Geohelminthiasis includes such helminthic diseases as ascariasis, hookworm, trichocephalosis, strongyloidosis.
- Flukes and tapeworms (cestodes), as well as some types of nematodes, belong to the number of biohelminths. To reach the invasive stage, they need to change one or two intermediate hosts, which can be fish, crustaceans, mollusks, insects. Pathogens of biohelminthiasis enter the human body when eating meat or fish that has not undergone sufficient heat treatment, drinking raw water. Representatives of biohelminthiasis are diphyllobothriosis, clonorhosis, opisthorchiasis, teniosis, teniarynchosis, trichinosis, fasciolosis, echinococcosis.
- Contagious intestinal worms includes infestations transmitted from person to person through personal contact, through common toilet items, dishes, underwear or by self-infection. These are enterobiosis, hymenolepidosis, strongyloidosis, cysticercosis.
Classification
Disease is classified depending on the biological characteristics of helminths, the way of existence in the external environment, ways of infection, habitat in the human body. Taking into account the biological characteristics of pathogens, there are:
- nematodes (ascariasis, enterobiosis, trichocephalosis, hookworm, necatosis, etc.)
- cestodoses (teniosis, cysticercosis, hymenolepidosis, teniarynchosis, echinococcosis)
- trematodoses (opisthorchiasis, clonorchosis, schistosomiasis, fasciolosis).
According to the mode of existence of parasitic worms in the environment, geohelminthiasis, biohelminthiasis and contact intestinal worms are distinguished. Infection with intestinal worms can occur by food, water, percutaneous route. Depending on the localization of pathogens in the human body, intestinal worms is divided into:
- Intestinal. In the human intestine, pathogens of ascariasis, enterobiosis, ankylostomidosis, trichocephalosis, strongyloidosis, trichostrongyloidosis, diphyllobothriosis, teniosis, teniarinchosis, hymenolepidosis, etc. are parasitized.
- Extra-intestinal. Extra intestinal helminths can live in the liver, gallbladder, blood vessels, subcutaneous tissue. Extra-intestinal parasitoses include filariasis, dracunculosis, opisthorchiasis, schistosomiasis, fascioliasis, clonorchosis, paragonimosis, trichinosis, cystocerciasis, etc.
In addition, in accordance with the localization principle, there are lumen (including intestinal) and tissue (skin and visceral) intestinal worms.
Symptoms
The clinical picture is very motley and consists of a general reaction of the immune system in response to the invasion of parasites and organ-specific lesions. During intestinal worms, acute or early (from 2-3 weeks to 2 months) and chronic phases (up to several years) are isolated. The main pathological effects of helminths on the human body include toxic and allergic reactions, mechanical damage to organs and tissues, alimentary and vitamin deficiency, and a decrease in immunological competence.
Acute phase
In the acute period, the main manifestations are due to the toxic-allergic effect of parasitic worms on the body. Patients have fever, skin rash, muscle pain, lymphadenopathy. Abdominal syndrome (dyspepsia, abdominal pain), pulmonary syndrome (dry cough, bronchospasm, shortness of breath), hepatolienal syndrome (enlargement of the liver and spleen), asthenovegetative syndrome (apathy, fatigue, sleep disorders, irritability) often develops.
The chronic phase
In the chronic phase of intestinal worms, organ-specific lesions predominate, mainly due to mechanical traumatization of the helminth parasitization site. Thus, dyspeptic disorders and abdominal pains are determining during intestinal worms. Violation of the absorption processes in the intestine is accompanied by polyhypovitaminosis, a progressive decrease in body weight. Iron deficiency anemia is a frequent companion of intestinal worms. With massive helminthic invasion, rectal prolapse, the development of hemorrhagic colitis, intestinal obstruction is possible.
In the chronic phase of intestinal worms, occurring with a predominant lesion of the hepatobiliary system, mechanical jaundice, hepatitis, cholecystitis, cholangitis, pancreatitis may occur. In the case of migration of pinworms with enterobiosis, the development of persistent vaginitis, endometritis, salpingitis is possible.
The chronic stage of strongyloidosis proceeds with the formation of gastric and duodenal ulcers. With trichinosis, the cardiovascular system (myocarditis, heart failure), respiratory organs (bronchitis, bronchopneumonia), central nervous system (meningoencephalitis, encephalomyelitis) can be affected. Due to the invasion of lymphatic vessels by filariasis with filariasis, lymphangitis, lymphedema of the extremities with edema of the mammary glands and genitals often develops. With echonococcosis, cysts of the liver and lungs occur, with suppuration of which complications in the form of purulent peritonitis or pleurisy are possible.
Against the background of intestinal worms in children and adults, the effectiveness of preventive vaccination and revaccination decreases, as a result of which the necessary protective level of immunity is not achieved. In the presence of concomitant diseases, intestinal worms modify and aggravate their course. The outcome of intestinal worms may be recovery (with natural death or expulsion of the helminth) or residual phenomena, often with disabling consequences.
Diagnostics
Based on clinical and epidemiological data, intestinal worms is mainly diagnosed already in the chronic stage. To identify the causative agent of intestinal worms, special laboratory methods are used: microhelminthoscopic (scraping for enterobiosis), helminthoscopic (examination of feces for worm eggs), helmintholarvoscopic, serological (ELISA), histological coprology. Feces, vomit, duodenal contents, sputum, urine, blood, skin biopsies, etc. can serve as the test material for the detection of eggs, larvae or fragments of mature individuals of helminths.
In intestinal worms, skin-allergic tests with helminth antigens may be informative. In order to identify and assess the severity of organ-specific lesions, instrumental diagnostics is widely used: Ultrasound of the liver, pancreas, FGD, colonoscopy, endoscopic biopsy, radiography and CT of internal organs, liver scintigraphy.
Treatment
A holistic approach to the treatment consists of etiotropic and post-syndrome therapy. Specific treatment involves the appointment of anthelmintic drugs, taking into account the type of helminth and the stage of invasion. The effectiveness of deworming is evaluated by the results of repeated parasitological examination. For etiotropic therapy of intestinal worms, the following groups of drugs are used:
- anti-hematodose (albendazole, levamizole, befenia hydroxynaphtoate, piperazine, pyrantel, etc.)
- anti-cestodose (niclosamide, albendazole)
- antitrematodose (tetrachloroethylene, hexachlorparaxylene, bithionol)
- drugs of a wide spectrum of action (mebendazole).
In intestinal worms, antibacterial drugs, enterosorbents, enzymes, probiotics, etc. are added to the main treatment. Symptomatic therapy of intestinal worms may include the appointment of antihistamines, intravenous infusions, vitamins, cardiac glycosides, NSAIDs, glucocorticoids. With echinococcosis, the main method of treating patients is surgical intervention (operations for cyst / liver abscess, echinococcectomy).
Prevention
Prevention of geohelminthiasis is carried out by hygienic education of the population, environmental protection from fecal contamination, instilling rules of personal hygiene in children. In terms of preventing the spread of biohelminthiasis, the deworming of domestic animals, veterinary and sanitary control over the sale of meat products, careful heat treatment of meat and fish plays an important role. In the prevention of contact intestinal worms, the main importance is the rupture of the mechanism of transmission of pathogens in organized, mainly children’s, collectives. It is advisable to carry out seasonal drug prevention of intestinal worms in families (for example, albendazole), regular parasitological examination of children and risk groups.