From Big Medical Encyclopedia

ENTEROBIOSIS (enterobiosis; Greek enteron a gut + bios life + - osis) — the helminthosis of the person caused by pinworms.

The disease was known still to Hippocrates and Aristotle. Ibn-Xing in «A canon of medical science» recommended to treat this disease of a bitter wormwood and men's fern. The activator is for the first time described by K. Linney in 1758

E. it is widespread everywhere. According to Peters (W. Peters, 1978), total number having this helminthosis in the world exceeds 350 million persons.

Etiology. Entero-bius vermicularis activator (L. 1758) Leach, treats 1853 type of roundworms (see Roundworms), to a class of roundworms of Nemato-da, a suborder of Oxyurata, the Okhu-uridae family. Pinworms — small nematodes of white color.

Length of a female is 9 — 12 mm, length of a male

is 2 — 5 mm. On the head end

of Fig. 1. The scheme of a structure of pinworms (and — females,

6 — a male): 1 — an actinostome; 2 — vesicles; z — a gullet; 4 — a bul-beads; 5 — a uterus;

6 — an anus; 7 — a sexual opening.

parasites (fig. 1) short kutikulyarny educations of an oval form — the so-called vesicles symmetrized on both sides are had. The tail end of a male is spiralno bent on the belly party. The tail end of a female is awl-shaped pointed. The actinostome passes into a long gullet, on the tail to-rogo there is a spherical or pear-shaped expansion — bulbus, being border between a gullet and intestines. Existence of a bulbus in back department of a gullet — a characteristic sign of all representatives of a suborder of Oxyurata. Bulbus of a gullet and a vesicle form the prisasyvatelny device providing fixing of adult helminths on a wall of a gut of the person. Intestines of parasites represent the direct tube which is coming to an end with an anus near the back end of a body.

Eggs of pinworms of oblong, a little asymmetric form (fig.

of Fig. 2. Microdrug of egg of a pinworm.

2). The size of eggs

is 50 — 60 X 20 — 30 microns.

Infection of the person occurs at a proglatyvaniye of the mature eggs containing larvae of helminth. Larvae are exempted from a cover of egg in a duodenum, go down in a lean and ileal gut where they several times fade and 14 — 15 days later after infection turn into puberal pinworms in a lower part of a small bowel. Puberal pinworms parasitize usually in a caecum, and at an intensive invasion — in lower parts thin and upper parts of a large intestine.

Males usually perish after fertilization of females. In a uterus of a mature female from 5 to 17 thousand eggs collect. The uterus of a pinworm filled with eggs, stretching to the big sizes, squeezes and shifts bulbus a gullet, breaks its prisasyvatelny action. Females lose ability to be fixed on a mucous membrane of a gut and under the influence of a vermicular movement quickly go down to a rectum. Females the active movements move along a wall of a rectum and creep out of an anus, is more often in evening and night time when the outside sphincter of an anal orifice is a little weakened. Having got on wet skin of perianal area, pinworms can creep in her limits. Postponement of eggs happens preferential in perianal folds, on border of skin and mucous membrane, in 4 — 6 hours of egg ripen to an invasive stage, in them larvae of helminth form. After an otkladka of eggs of a female perish. Longevity of a female in intestines makes 3 — 4 weeks.

Epidemiology. The only source of an invasion is the person sick with an enterobiosis. Eggs, as a rule, are found on perianal folds. Only sometimes adult females of pinworms can be found in excrements, with to-rymi they are removed to the environment. Eggs are capable to develop at f 22 — 40 ° (optimum temperature 35 — 37 °). At t ° 41 — 42 ° they perish within several minutes, at f no more than 7 days survive,

and at t ° — 15 ° perish in 40 — 50 min. At humidity lower than 70% development of eggs stops.

Infection occurs generally through hands of the patient, to-rye become soiled eggs of pinworms at

a pochesyvaniye of pruritic places. Eggs of pinworms can get on bed and underwear, from there — on a floor, objects of use, to food, and also to be brought in a nose and in a mouth in the course of breath and then to be swallowed. In this regard the infested persons often are exposed to repeated infections. AA. it is most eurysynusic among the children attending kindergartens and pupils of elementary grades of school. At children of babyhood and at adults E. meets seldom.

Pathogeny. The major pathogenetic factors at E. mechanical impact of larval stages of pinworms and puberal individuals on tissues of intestines, and also toxic and allergenic influence on an organism of the owner of products of exchange and disintegration of parasites are. The mechanical irritation and impact of secrets and ekskret of helminths on a mucous membrane of ileocecal area leads to disturbance of motor and secretory function of a stomach and intestines, development of inflammatory changes — a typhlitis, appendicitis, a proctosigmoiditis, etc. An allergy at E. it is shown by an eosinophilia of blood, eosinophilic infiltration of a wall of intestines. The enterobiosis is constantly accompanied by dysbacteriosis, to-ry leads to the raised susceptibility of the infested persons to intestinal infections. Having combed penetration of a bacterial flora through the skin injured as a result perianal area, promotes development of dermatitis. Pinworms can migrate in a vulva and a vagina that leads to development of a vulvovaginitis (see).

Pathological anatomy. Fixings of pinworms on a mucous membrane of a wall of intestines in it result semi-lunar deepenings with desquamation of an epithelium, punctulate hemorrhages, petechias, erosion, micronecroses. In a mucous membrane of intestines find infiltrates from neutrophilic leukocytes, lymphocytes, eosinophils. Through a blemished surface of a mucous membrane helminths are capable to be implemented into deeper tissues of intestines where around them granulomas from epithelial, colossal cells and eosinophils form. At E. the hyperplasia of the lymphoid device comes to light went. - kish. path.

Immunity. A susceptibility of people to E. high. At most of patients relative immunity develops, it is more rare does not develop at all that leads to repeated repeated infections and a long current of an invasion. At individuals infection does not conduct to a course of a disease that the witness

about their resistance to an invasion as a result of immunity can - stvovat or natural immunity to E. Boley rare infection of adults is defined by existence a gigabyte rather. skills, than age immunity.

Clinical picture. At a number of persons, infested by pinworms, AA. proceeds asymptomatically. At an intensive invasion in 2 — 3 days after infection there are abdominal pains, nausea, an unstable chair, the general weakness, increased fatigue, irritability, the sleep is interrupted. Upon completion of puberty of females of pinworms, at their vypolzaniye from an anus and the beginning of process of a yaytsekladka the itch in perianal area develops. The itch can be constant, painful. Children become whimsical, uneasily sleep, lose flesh. Their appetite is reduced, disorders of function amplify went. - kish. path. In blood the moderate eosinophilia comes to light, for a cut the wavy current is characteristic: each rise in level of eosinophils testifies to new infection. At a rektoromano-skopiya small erosion on a mucous membrane of a rectum, strengthening of the vascular drawing quite often come to light.

The most frequent complications E. cracks and eczema in perianal area, at girls (is more rare at women) — a vulvovaginitis are. Children sometimes have a bed wetting (see).

The diagnosis is based on a wedge, a picture and results a lab. researches. Use a method of scraping from perianal folds, the Gim-melfarba method and Graham's method with a cellulose adhesive tape (see. Helmintologic methods of a research). Examinations are conducted in the morning, before commission of a toilet, or in the evening, before going to bed. Triple inspection in

1 — 3 day is necessary at least. The diagnosis confirms also detection of the pinworms who are creeping out of an anal orifice outside during an evening or night itch.

Differential diagnosis is carried out with a number of the diseases which are also followed by an itch in perianal area — with a diabetes mellitus (see a diabetes mellitus), dysfunctions of a thyroid gland, hemorrhoids (see), ulcers and fistulas of a rectum (see), a senile itch (see the Itch skin) and SP-

perform Treatment in vanki-number, Kombantrinum, Mebendazolum and piperazin. Vankin appoint once inside after food at the rate of 5 mg! kg. Due to a possibility of a reinfestation treatment is reasonable to repeat 2 — 3 times at an interval of

2 weeks. Efficiency of treatment exceeds 90%.

Kombantrinum is accepted after food once at the rate of 10 mg! kg. In 2 and 4 weeks treatment is repeated.

Mebendazolum is appointed once during food to children at the age of 2 — 10 years in a dose of 0,025 — 0,05 g, to children 10 years and adult — 0,1 g are more senior. For fixing of success treatment is repeated in 2 and 4 weeks.

Drugs of piperazin (sulfate, adipate, citrate) are appointed according to the identical scheme: 2 — 3 five-day bucketed cycles of 5 days. A daily dose for children at the age of 1 year — 0,4 g; 2 — 3 years — 0,6 g; 4 — 6 years — 1 g; 7 — 9 years — 1,5 g; 10 years are also more senior — 2 g. The daily dose is divided into 2 — 3 receptions.

The first control examination is conducted in 2 weeks, the second — in 3 weeks, the third — in 4 weeks after treatment. At inefficiency of the carried-out treatment it is repeated, but not earlier than in 2 weeks after the termination of the first course of treatment.

Forecast favorable.

Prevention consists in identification and treatment of patients, and also in the prevention of infection of healthy faces. Children in preschool institutions, personnel of these institutions and school students of 1 — 4 classes inspect on an enterobiosis once a year. It is necessary to wash hands before food and after visit of a toilet. To the patient E. it is recommended in the mornings and evenings to be washed away by water with soap then to clean nails and carefully to wash hands; to sleep in pants (underpants), to-rye it is necessary to change, boil or iron daily the hot iron. Trousers, skirts also iron the iron, bed linen is ironed by each

2 — 3 days. Cleaning of premises needs to be made wet rags, to-rye later cleaning it is necessary to boil. The dignity is of great importance. - a gleam, work among the population.

Bibliography: Alekseeva M. I. and Lysenko A. Ya. Comparative efficiency and portability of treatment of an enterobiosis vaniny, Kombantrinum and Vermoxum, Medical parazitol., t. 49, No. 5,

page 34, 1980; Helminthoses of the person, under the editorship of F. F. Soprunov, M., 1985; D e-in and with And. Medicinal therapy of intestinal helminthoses, the lane with English, M., 1975; The Multivolume guide to microbiology, clinic and epidemiology of infectious diseases, under the editorship of H. N. Zhukova-Vereshnikov, t. 9, page 581, M., 1968.

M. I. Alekseeva.