Helminthiases / / April 27, 2016
Ascaridosis (Lat.), Ascariasis (Eng.), Ascaridiose (fr.), Ascaridiosis (App.).
Ascariasis - helminthiasis occurring in the early phase of allergic phenomena in later - preferably with gastrointestinal disorders.In the last phase, severe complications requiring emergency surgery.Distributed everywhere except in areas of permafrost, deserts and dry steppes.
Etiology and epidemiology
Pathogen - round worms Ascaris lumbricoides.Female 24-40 cm in length, the male -. 15-25 cm male rear end bent into a hook.The eggs of Ascaris size 0,05-0,07X0,04-0,05 mm.There are also "unfertilized eggs" (egg cell) size 0,05-0,1X0,04-0,06 mm.
Ingestion man mature eggs of Ascaris of them in the small intestine hatch into larvae, which are introduced into the blood vessels of the portal vein system and are recorded in the liver.They penetrate into the hepatic vein, inferior vena cava, the right heart and pulmonary circulation.In the lungs the larvae out of the blood vessels in the bronchial tubes, moving up to the larynx
source ascariasis is the only person in the gut which are parasitic females and males of Ascaris.One female lays a day about 240,000 immature eggs that are in the feces of the patient stand out.Ripening takes place eggs in the soil.Infection ascariasis is usually carried out by ingestion of mature eggs of worms contaminated vegetables, berries, fruit, soil particles.Infestation ascariasis is particularly high in areas where the soil gardens fertilized human faeces.
Pathological anatomy and pathogenesis
Ascaris injure the intestinal wall, causing hyperemia, hemorrhage, and sometimes even death.Movement of adult ascarids in the intestine, it is accompanied by cramps, worms cause irritation of nerve endings in its wall and toxic-allergic influence their metabolism products, can lead to acute intestinal obstruction.Spastic intestinal obstruction may occur and if it contains only a single roundworm.When askaridoznoy ileus violations occur vascularization its walls, the appearance in it necrosis, perforation, in some cases with helminths stepping into the abdominal cavity and the development of peritonitis.
penetration of ascarids in the liver leads to cholangitis, creating favorable conditions for secondary bacterial infection with the development of suppurative processes in the bile ducts and liver parenchyma itself.It should, however, always used to read the possibility of cases of post-mortem zapolzaniya ascarids in the liver.
in the pancreas when it Ascaris infestation occur hemorrhage, necrotic processes.Described the presence of small nodules with helminth eggs.The penetration of ascarids in the genitourinary organs is due to the close anatomical connections of the gut, often observed in chronic inflammatory processes, as well as after some operations (transplant ureters into the colon, etc.).
The clinical course ascaridosis distinguish two phases - early and late.The first is related to the migration of Ascaris larvae, the second - with helminths parasitizing the intestine.
In the early phase of ascariasis sometimes flows were obliterated.In other cases, there are marked malaise, cough, dry or with sputum production, which sometimes has a small admixture of blood.Subfebrile temperature is usually, at least 38 ° C and above normal in some patients.A number of patients in the lung marked dry and wet wheezing.In some patients there is a dry or eosinophilic exudative pleurisy.Occasionally increased liver and spleen.The skin often appear rash urticaria.Develops conjunctivitis.
X-ray examination revealed pulmonary infiltrates, which can be single or multiple, point-and occupying an entire lung lobe.Typically, the diameter of 2.5-4 cm. These are called eosinophilic infiltrates, as they are characterized by blood eosinophilia up to 60-80% with the normal amount of white blood cells or moderate leukocytosis.ESR is usually normal, rarely increased.Hold infiltrates from a few days to 2-3 weeks.In some patients, they disappeared, they reappear.
late (intestinal) ascaridosis phase sometimes occurs in the erased form that does not guarantee against serious complications.Most patients complain of fatigue, change in appetite (usually fall), nausea, rarely vomiting, abdominal pain, sometimes wearing cramping in nature.Some patients have diarrhea, while others - constipation or diarrhea alternating with constipation.
In the study of gastric contents of about 50% of patients revealed a decrease of acidity up to ahilii, 20%, on the contrary, the acidity increased.Described dizenteriynopodobnye, cholera and typhoid-like syndromes, however, should take into account the possibility of combining ascaridosis infectious diseases.From the nervous system in ascariasis common headache, dizziness, mental fatigue.
In some patients, reduced blood pressure.Sometimes asthmatic bronchitis.
Recognition of ascariasis in the early phase of the disease based on clinical, serological tests positive, the discovery of Ascaris larvae in the sputum.In the late phase of the disease is crucial to the discovery of Ascaris eggs in stool, appearing here 2-3 months after infection.The presence in the intestines of some males proved the determination in the urine of the patient volatile fatty acids or intestinal fluoroscopy, when the background of the contrast mass roundworm can be seen as a bright stripe width 0.4-0.6 cm
treatment,forecast and prevention
Specific treatment of ascariasis in the early phase is unknown.In severe form of the disease used antihistamines.In late (intestinal) phase usually use piperazine.
piperazine administered 2 times a day with an interval between doses 2 hours in single doses of 1.5-2 Treatment continued for 2 consecutive days.Laxative allowed only if constipation.In adults, and school children ascariasis treatment can be carried out by a single destination in a daily dose piperazine.In preschool children, this method is not sufficiently effective.
Ascariasis should be recognized as a dangerous disease as serious and even fatal complications can crop up with him.
fight against ascariasis is carried out by mass and routine inspection and treatment of the population, health improvement of populated areas.Inspect to ascariasis is necessary in all patients who undergo surgery.Fruits and Vegetables, edible raw, wash and scald with boiling water.Roundworm, isolated from the patient, boiled, or burned, boiling water is poured feces.