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The Hemotoxins of Intestinal Parasites. A Critical Summary with Notes on Some Cases

1924; American Society of Parasitologists; Volume: 10; Issue: 3 Linguagem: Inglês

10.2307/3270874

1937-2345

Joseph Leidy,

Parasite Biology and Host Interactions

The mechanical and reflex disturbances produced by animal parasites in the intestinal canal and other organs of the body have long been recognized by pathologists and clinicians. The researches of economic parasitologists and the occasional reports by clinical observers indicate the presence of other factors deserving of further investigation. That certain parasitic worms secrete substances that effect the blood of their hosts deleteriously has been shown conclusively by the researches of Tallqvist, Schwartz, Schaumann and others. The broad tapeworm of man which is known to produce severe anaemia contains a hemolytic agent according to the experiments and researches of Schaumann and Tallqvist. Hookworms secrete a hemolysin and an anticoagulin according to Calmette and Breton, Loeb and Smith. The whipworm Trichuris apparently secretes a hemolysin according to the investigations of Whipple (1909) and Sarin (1913). In 1865 Kuttner cites a case of blood destruction cured by expelling ascarides. According to Filatoff (1897) Karaven cured a case of pernicious anemia by expelling ascarides from the intestine. Francois (1906) in the course of his investigation of miners found many cases of severe anemia in which hookworms were not present, but which showed numerous ascaris eggs in the feces, and Schwartz has shown that the anemia in hogs and horses is frequently associated with Ascaris lunbricoides infection. Two views as to the cause of parsitic anemia have been held by different authorities. One that the anemia results from depriving the host of blood by sucking the other through the secretion of a hemolysin, a hemotoxin hemolytic in character. Owing to the fact that the abstraction of blood by parasites appears to be inadequate as an explanation of the causes of anemia in parasitic diseases. and in tapeworm infections due entirely to the presence of parasites, the direct abstraction theory as applied to hookworm anemia is inapplicable. From the researches of Schwartz and others the view that hemolysins from parasites are of etiological significance in parasitic diseases appears to be entirely justified. Huber (1870) expressed the opinion that many symptoms put down to round worms are caused by a peculiar irritating matter which they