TRICHOCEPHALIASIS. 559 



to Askanazy. What Askanazy actually said was that he had isolated "an 

 iron containing pigment from the epithelial cells of the intestine of the 

 parasite." So far as we know, neither blood nor other positive evidence 

 of blood absorption has been found in Trichuris. 



These parasites do attach themselves to the intestinal wall during the 

 life of the host by transfixation and direct penetration by the head end, 

 and that these locations may show bright, hypertemic spots and become 

 eroded or even ulcerated, is proved beyond doubt. However, the lesions 

 formed by this action are not as a rule sufficient to explain the symptoms, 

 unless we accept some peculiar hemolytic or other toxic action of the 

 parasite. It is certain that the mechanical loss of blood from these 

 infections is not sufficient to account for the symptoms and a definite 

 toxic action has not been proved. The nervous symptoms and some of 

 the gastro-intestinal ones might be explained from the mechanical action 

 of the parasites by an hypothesis similar to that of Mayo's embryologic 

 formation used for the explanation of similar, symptoms in certain cases 

 of chronic appendicitis and gall bladder diseases. However, this is only 

 a hypothesis and does not account for the severe anaemia, which after all 

 is the important manifestation. The nature of the action of these para- 

 sites in producing disease has not been satisfactorily explained, but this 

 should not be accepted as proof of their commensalism. 



Pathology. — The general pathologic changes in fatal cases of trichocephaliasis 

 are severe, secondary anajmia. The special conditions are the presence of the worms 

 and certain changes at their points of attachment to the mucous membrane of the 

 bowel or appendix. Several changes have been described by different authors, 

 which in the main are hyperemia of the mucosa with hemorrhagic points ; erosions 

 and superficial ulceration of the mucous membrane, surrounded by areas of cell 

 infiltration ; and in some instances deep ulceration or other inflammatory reac- 

 tions extending to the muscular coat of the bowel. Several observers have shown 

 that the worms are attached to the mucous membrane during the life of the 

 patient. They attach themselves by transfixing a fold of mucous membrane, by 

 penetrating the glandular follicles, and by direct perforation, the head being- 

 embedded in the deeper layers of the bowel wall. After the death of the 

 patient, the worms detach themselves and at autopsy are usually found free in 

 the bowel. Several authors have demonstrated this direct attachment to the 

 intestine. Corroborative evidence is furnished by the fact that they do not 

 appear in the discharges even after violent purgation. The worms were not 

 passed in a number of cases of successful treatment, when the disappearance 

 of eggs from the faeces showed that they had been destroyed. In these instances 

 we can only assume that the parasites have been killed and remain attached to 

 the mucous membrane of the intestine after death. 



Incidence. — This is one of the most frequent of all parasitic infections of man 

 and Garrison has shown it to be the most prevalent in the Philippine Islands. 



Some of the statistics in percentages are as follows: 



French & Boycott (1905), London 7.8; (1887), Erlangen, 11.1; (1887), Erlan- 



gen (Insane), 100. Leukart (1887), Dresden, 2.5; (1887), Kiel, 32.2; (1879), 



Dublin, 90. Cobbold ( 1879), Greenwich, 69; ( 1877), Paris, 30. Davaine (1877), 



Naples, 100. Blanchard (1889), Bale, 23.6. Garrison, Ranson, and Stevenson 



79284 8 



