Diphyllobothriasis

Diphyllobothriasis - a helminthiasis proceeding with signs of a primary lesion of a gastrointestinal tract and often accompanied by development of a megaloblastic anaemia.

Aetiology. Diphyllobothriasis originators concern group Pseudophylidea and total 12 kinds of fishworms, from which the fishworm wide (Diphyllobothrium latum) is the most widespread and studied (Unney, 1758, Lube, 1910). The length of the strobile consisting of the big number of segments (to 4000), reaches the Scolex in length of 3-5 mm has 2-9 m. the prodolgovato-oval form, is flattened from sides, on lateral surfaces - two clefts (bothrium) by means of which the parasite is attached to an intestine mucosa. Fishworm eggs widely oval, large (70 x 45 microns), with a two-planimetric cover, have on one pole a lid, on other - a hillock. Parasitizing in organs of the definitive master, fishworms excrete the unripe eggs which development descends in fresh-water reservoirs. The blastemal formed in egg (coracidium) leaves in water later 6-16 days. At temperature more low +15C0 coracidium from eggs do not leave, remaining teleorganic to 6 months After an ingestion fresh-water maxillopods coracidium in 2-3 weeks turn to procercoids. In an organism of the fishes, swallowing maxillopods, procercoids inpour into an internals and muscles where in 3-4 weeks educe in plerocercoids in length to 4 sm and having the generated scolex. In puberal fishworms plerocercoids turn in an organism of the definitive master.

Epidemiology. Diphyllobothriasis diffusion is bound to large fresh-water reservoirs. Its locuses prevail in Northern Europe, East Mediterranean, around Great Lakes the USA, in Canada and on Alaska. Infestation of the human descends at the use fresh, not enough the salted caviar and crude fish. Definitive masters of a fishworm wide are the human, dogs, cats, bears, foxes, pigs. Mediate masters - fresh-water maxillopods (a Cyclops, Diaptomus), additional - fresh-water fishes. Lifetime of a fishworm wide in a human body can reach 25 years, in an organism of a dog 1,5-2 years, cats - 3-4 weeks.

Pathogenesis. In development of clinical implications of disease play a role mechanical influence of helminths on an intestine side in a place of its affixion with development of an atrophy and necrosises; a boring of interoceptors with formation of vistsero-visceral reflex reactions and is excitatory-trophic disorders; allergic responses owing to a sensibilization of an organism of the master products of an exchange of a fishworm; an endogenous hypovitaminosis of cyancobalamin and Acidum folicum, resulting disturbance of absorption and synthesis by the macroorganism and a competition for them from a helminth.

Symptoms and flow. The incubation interval compounds from 20 till 60 days. The diphyllobothriasis can have both clinically demonstrative, and latent flow. Disease begins gradually. There is a nausea, is rarer - vomiting, pains in epigastriums or on all gaste, appetite decreases, the chair becomes unstable, there is a subfebrile condition. In cases of long flow of a helminthiasis at some patients there can come obstructive intestinal impassability because of a clump of a considerable quantity of helminths in a thin intestine. In parallel appear and signs of an astheno-neurotic syndrome (delicacy, fatigability, giddiness) and В12-deficit anemias accrue. Arise a pain and paresthesias in tongue, in serious cases it is observed Hunter's glossitis - presence in tongue of bright red, painful maculae, fractures. Later tongue papillas will atrophy, it becomes smooth, nitidous ("varnished"). The tachycardia, dilating of borders of heart, soft systolic hum on an apex, a nun's murmur, a hypotension becomes perceptible. The quantity of erythrocytes and haemoglobin sharply decreases, the colour indicator remains high, increase of an indirect bilirubin of blood serum, a relative lymphocytosis and a neutropenia, an ESR acceleration becomes perceptible. At a fresh invasion the eosinophilia can be taped. In a blood smear in a small amount megaloblasts, Jolly's bodies, rings Kebota, hyperchromatic macrocytes, polychromatophilous erythrocytes and erythrocytes with a basophilic stippling are found. The number of erythrocytes and quantity of haemoglobin remain with some patients within norm, but there are macrocytosis signs (Price-Jones curve alteration to the right). Expression of an anaemia depends on character of a food and life conditions. At serious flow of disease the funicular myelosis educes: unsharp paresthesias, disturbances of superficial and deep sensitivity.

The diagnosis and the differential diagnosis. In diagnostics the epidemiological anamnesis (stay in precinctive range, the use of the crude fish, the salted insufficiently caviar) is informative. Often sick reporting about abjection with a feces of parts of helminths. For a diphyllobothriasis abjection of scraps of a strobile that distinguishes it from an invasion tapeworms (bull and pork) is characteristic. The differential diagnosis between a diphyllobothriasis and Addison-Biermer anaemia is possible on the basis of definition in contents of stomach Castle's factor which at a pernicious anaemia is absent. The definitive diagnosis is established at detection in a feces of eggs of a helminth.