From Big Medical Encyclopedia

NEMATODOSES (nematodosis, the singular) — the diseases caused by nematodes — round helminths with the extended cylindrical and nesegmenti-rovanny body.

At the person the following Nematodoses are registered: abbreviatoz, akantokheylonematoz (see), ankilostomidoza (see), ascaridosis (see), brugioz (see), vukhererioz (see), gepatikolez, giatostomoz (see), infestation with Gongylonema (see), dioktofimoz (see), dirofilariasis, dracunculosis (see), loasis (see), lagokhilaskaridoz (see), mansonelliasis (see), metastropgilez (see), onchocercosis (see), singamidoz (see), strongyloidosis (see), telyazioz (see), ternidentoz, toksaskaroz (see), toksokaroz (see), tominksoz (see), trichinosis (see), trichuriasis (see), trikhostrongiloidoza (see), ezofagostomoz (see), enterobiosis (see).

Sometimes find larvae or young immature nematodes, it is not possible to define a look to-rykh definitely. In such cases they are called and din to nematodes and. Diseases of the person under the name anizakiaz, caused by implementation in a wall of a stomach, a caecum of larvae agamonematod are abroad described (identified as Ferranova sp.) and shown intestinal colic, fever, an eosinophilia, development of infiltrate, abscess of intestines, peritonitis.

Are known to Nek-rye N. (an ascaridosis, an enterobiosis) since ancient times. Parasitizing of ascarids, pinworms it is mentioned in Ebers's papyrus, in Hippocrates, Ibn-Sina, Aristotle's works. The main researches but anatomy, a systematics and biology of nematodes, on a pathogeny and clinic of nematodoses belong to 18, 19 and 20 centuries. The theory of spontaneous generation of helminths was refuted by P. S. of Pallas (1760) claiming that infection with helminthoses, including nekhmatodozam, happens at a proglatyvaniye of eggs of helminths to food and water. Opened for J. Pedzhet in 1835 trichinellas; J. Morganyi in the middle of 18 century described a trichuriasis; A. Dubini in 1838 — a dochmiasis, A. Normand in 1876 — a strongyloidosis, J. N. Demarquay in 1863 and Vukhe-rer (O. of E. H. Wucherer) in 1866 was found in the person of microfilarias. Gerbst (G. Herbst, 1848), Tsenker (F. Zenker, 1860) established that infection with a trichinosis occurs at the use of meat, invazi-ro bathing larvae of trichinellas.

A. Fedchenko (1869) proved that the person catches drakunkulezy at drink of the water containing Copepoda of the crustaceans infected with larvae of the activator of a parasitic worm. Munson (1878) revealed transfer of a vukhererioz through mosquitoes. S. P. Botkin (1884) noted value of neuroreflex influences in a pathogeny of ankilosto-mndoz. I. I. Mechnikov (1901), M. V. Veynberg (1907), K. I. Scriabin (1923) showed a role of nematodes as conductors of microbic flora in tissue of a human body. The allergic nature a wedge, manifestations of an early phase of nek-ry N. was shown by V. P. Bazhenov (1935) on the example of a trichinosis.

The most widespread N. are an ascaridosis, ankilostomidoz, a necatoriasis, a strongyloidosis, a trichuriasis, trikhostrongiloidoza, a trichinosis, an enterobiosis. All of them meet also within the USSR. Filariases are widespread in the tropical countries of Africa, Asia, Latin America and Oceania (vukhererioz, brugioz, a loasis, an onchocercosis, akantokheylonematoz). The majority of geonematodoses (activators — the nematodes developing without smeaa of owners) belongs to endemic to helminthoses (see). So, the ascaridosis, a trichuriasis, ankilostomidoza, a strongyloidosis are preferential widespread in areas with a warm and humid climate and are absent in a zone of permafrost, are rare in warm, but dry areas. A specific place is held by the enterobiosis widespread on all globe since infection with it occurs almost only in the conditions of the dwelling of the person. Distribution of the majority of bionematodoses (activators — the nematodes developing with participation of intermediate owners) depends on an area of intermediate owners, climate, a landscape of the area. So, filariases meet only in tropics where there are favorable conditions for life and reproduction of insects — intermediate owners of the activator, and also for development of larvae in them fi-lyariid. A trichinosis is carried to natural and focal diseases as it occurs not only at the person, but also wildings (a boar, a bear, a fox, etc.).

Activators H. of the person — parasitic nematodes (the Neina-thelminthes type, C. Nematoda). Nematodes parasitize also at animals and plants. Along with parasites there is a large number of the free living roundworms living in the soil and water.

The body of nematodes — a spindle visible, threadlike, is more rare than other form, from 1 mm to 1 m long and more. The cuticle is multilayer, smooth or from cuticles yarny figuration. Under a cuticle there is a hypoderma and a layer of somatic muscles. Circulatory and respiratory systems are absent. The nervous system is presented near by a pharyngeal nervous ring with the departing longitudinal trunks. The alimentary system opens an actinostome and comes to an end with an anus (at females) or an opening of a foul place (at males). The actinostome is surrounded with the lips (not always) bearing eksteroretsep-Torahs. Sexual channels at males open in a foul place, at females — an independent sexual opening. Eggs can be various in a form, size and differ in unequal resistance to conditions of the environment. Parasites strike many bodies and fabrics. The ascarid (Ascaris lumbri-coides), a pinworm (Enterobius vermicularis), a threadworm (Trichoceplialus tri-chiurus), a nekator (Necator america-nus), ankylostomas (Ancylostoma duo-denale, A. braziliense), etc. live in various departments of intestines. Puberal trichinellas (Trichinella spiralis) parasitize in a mucous membrane of a small bowel, and their larva — in skeletal muscles. Dracunculus medinensis lives in hypodermic cellulose and synovial bags. Other types of nematodes parasitize in an eye (Loa loa), a pericardium and pararenal fabric (Acanthocheilonema perstans), in kidneys (Dioctophyme renale) etc.

Activators of geonematodoses develop without change of owners. Their eggs and larvae which are allocated with a stake of patients ripen to an invasive stage in the environment — the soil, water. Infection of the person with geonematodoses happens at a proglatyvaniye of mature (invasive) eggs and larvae of nematodes to particles of the soil, water, at contact with the contaminated objects. Larvae of ankylostomas can get into a body and through skin. Development of activators of bionematodoses is connected with change of owners. So, the vukhereriya in a stage of puberty parasitizes in limf, to system of the person, and its larva (microfilaria) circulate in blood. The intermediate owner of a vu-hereriya — nek-ry species of mosquitoes; during attack on the patient vukhe-reriozy they together with blood perceive larvae of this helminth. In a body of a mosquito of a larva develop, become invasive and at the subsequent krovososaniya-x mosquitoes are transferred to people. At a trichinosis the same individual consistently is at first a definitivny (final), and then intermediate owner since in a stage of puberty the trichinella parasitizes in a mucous membrane of a small bowel, and in a stage of a larva — in cross-striped muscles. Infection • bionematodo the deputy occurs differently. So, are infested by a dracunculosis (parasitic worm), swallowing with water of Copepoda of the crustaceans infected with larvae of a parasitic worm; infection with a trichinosis occurs at consumption of meat of the animal containing larvae of trichinellas; filariases catch at a sting intermediate owners — mosquitoes, gadflies, midges. N.'s distribution depends on the level of the general and sanitary culture of people, their professions and working conditions, a dignity. improvements of the inhabited places, the organizations to lay down. - professional, actions.

Nematodes cause a sensitization of an organism with development of the allergic reactions which are especially expressed at migration of larvae in fabrics, mechanically damage fabrics and bodies of the owner, break functions of an organism. At high intensity invasions (see) and intestinal localization they reduce absorption of feedstuffs and vitamins that causes development of anemia, burdens the course of other diseases, suppresses immunity, slows down development of children, reduces working ability of the person etc.

The changes observed in an organism at N. depend on localization patol, process; e.g., at a trichinosis it is noted allergic miositis (see), an encephalomeningitis (see. Encephalitis ), myocarditis (see), system vasculitis (see); at an ascaridosis, an enterobiosis, a trichuriasis, dochmiases signs of a gastroduodenit are found (see. Gastritis , Duodenitis ), a coloenteritis, inflammatory changes from other bodies and systems are more rare. At all N. changes of allergic character are observed: kruglokletochny and eosinophilic infiltration in various bodies and fabrics, at death of larvae in fabrics formation of granulomas.

The person is susceptible to infection with pathogenic nematodes at any age. Easier children catch. After a disease the temporary relative immunity which is shown decrease in intensity of a reinfestation, delay of development and reduction of longevity of nematodes, decrease in fertility of females, a phenomenon of self-release of patients from parasites develops.

The clinical picture H. is diverse. At localization of activators in intestines (e.g., an ascaridosis, an enterobiosis etc.) abdominal pains, dispeptic frustration are noted. At defeat (trichinosis) muscle pains arise activators of muscles. Defeat urinogenital and limf, systems, and also an organ of sight is observed at a filariasis. T1ri all N. the eosinophilia is noted. Sometimes N. proceed without symptoms.

The diagnosis is based on kliniko-epidemiological and a lab. data — results koprologiche-sky, larvoskopichesky and immunol, researches, blood test (see. Helmintologic methods of a research ).

N.'s treatment is carried out by protivone-matodozny drugs, to the Crimea piperazin, ditrazin, Naftamonum (alkopar), diphezyl, levamisole (decarice), Mebendazolum (Vermoxum), etc. belong. The choice of drug depends on a form H. (see in separate articles).

N.'s most has rather high-quality current, and timely treatment completely eliminates a disease. Lethal outcomes are possible, however, it is the most frequent at a trichinosis. The forecast serious at development of complications, napr, an elefantiaza at a vukhererioza, damages of eyes at an onchocercosis.

Prevention is provided with holding all-sanitary actions, planned treatment of the infested persons (see. Deworming ), fight against insects — intermediate owners (see. Disinsection ), protection against stings of insects, sanitary education, veterinary sanitary inspection (see) behind slaughter of the cattle.

Seldom found Nematodoses. Abbreviatoz — the helminthosis of a stomach, gullet and a small bowel caused by a nematode [Abbreviata caucasica (Linstow, 1902) Schulz, 1927]. The male has the size of 14,34 X 0,9 mm; a female — 24,74 X 1,18 mm. Eggs (0,062 X 0,042 mm) of an ellipsoidal form, contain a mature larva. Definitivny owners — a monkey, the person. Intermediate owners are various bugs and cockroaches. It is registered at people in the nek-ry countries of Africa (the Republic of South Africa, Uganda, etc.), Central America (Panama), in Asia (Israel). At monkeys — in Angola. In the USSR one case of an abbreviatoz in the Caucasus is described. The pathogeny and clinic are not studied. The diagnosis is made on the basis of detection of eggs in excrements.

Gepatikolez — helminthosis of a liver, the activator to-rogo is a nematode this. threadworms — Hepaticola hepatica (Bancroft, 1893) Travassos, 1915. The activator parasitizes hl. obr. at rodents, is more rare at dogs. It is described several cases of a gepatikolez at the person in India, the USA (including one, ended letalno) proceeding with abdominal pains, fever, an eosinophilic leukemoid test, a hepatomegalia, ascites. The diagnosis is made on the basis of detection of eggs of helminth in punctate from a liver.

Ternidentoz - the helminthosis caused by a nematode of Ternidens deminutus (Railliet et Henry, 1905). Occurs at natives of the nek-ry countries of Africa (Southern Rhodesia, Mozambique, Tanzania, etc.), it is frequent in combination with an ascaridosis, a trichuriasis and ankilostomidoza-m. Often find in monkeys in Africa and Asia. Parasitizes in intestines. Males (9,5 X 0,56 mm) and females (16 X 0,7 mm) by the size, size and a form have looking alike to ankilostomida!!. Eggs also remind eggs ankilostomid, but the big sizes (84 X 40 microns). Infection occurs during the swallowing invasive larvae. Having got into intestines, larvae are implemented into thickness of a mucous membrane, forming parasitic small knots. 6 — 8 days later they leave in a gleam of a gut again, are attached and gradually turn in the puberal helminths which are erythrophages. In an early phase of a disease there is a skin itch, urtikariya, an eosinophilia are observed. In a late stage — nausea, vomiting, abdominal pains, locks, ponosa, sometimes develops anemia. In cases of weak intensity of an invasion ternidentoz proceeds asymptomatically. The diagnosis is based on detection of eggs in Calais.

Bibliography: Davies A. Medicinal therapy of intestinal helminthoses, the lane with English, M., 1975; Kassirsky I. A., etc. Guide to tropical diseases, M., 1974; K. M. Mullet of iplot-nicknames N. N. Lectures on infectious and parasitic diseases, p.1, M., 1970; The Multivolume guide to microbiology, clinic and epidemiology of infectious diseases, under the editorship of H. N. Zhukova-Verezhnikov, t. 9, page 543, M., 1968; Bases of a nematodologiya, under the editorship of K. I. Scriabin, t. 1 — 28, M., 1949 — 1977; Podjyapol-Skye V.P. and Kapustin B. F. Helminthic diseases of the person, page 436, M., 1958; Smirnov G. G. Medical helminthology, L., 1959; Schultz R. S. and Gvozdev E. V. Bases of the general helminthology, t. 1, M., 1970; Manson’s tropical diseases, ed. by Ch. Wilcocks a. P. E. C. Manson-Bahr, Baltimore, 1972.

V. K. Karnaukhov; Yu. K. Bogoyavlensky (etiol.).