ECHINOCOCCUS DISEASE 539 



of Demantke, Lehne and Klehmet. The echinococcus is usually unilocular. 

 The right heart is more frequently implicated than the left. The seat of the 

 parasite is the heart muscle, and here it attains its growth. For the most 

 part its course is marked by no symptoms, at least of parasitism. The condi- 

 tions are different, however, if the distended cyst grows into the cardiac 

 cavities and bursts its sac. The symptoms of cesto-embolism in this case 

 do not differ decidedly from emboli as the result of thrombi. According to 

 the size and extent of the embolus, according to its benign or malignant 

 (putrid) composition, and according as the smaller or larger vessels are ob- 

 structed, the disturbances due to emboli of cestodens show varying charac- 

 teristics. We should digress too far if we further discussed these extremely 

 complicated conditions. Death often results suddenly without preceding symp- 

 toms. In some cases there are antecedent signs of disease of the heart and 

 of the lungs; in other cases death takes place after a long illness with com- 

 plications such as perforation and embolism of daughter-cysts. 



In emboli into the greater circulation the perforating cyst is usually situ- 

 ated in the left heart, or the cysts develop from a pulmonary echinococcus 

 which has burrowed into the pulmonary vein. Death, as a rule, occurs sud- 

 denly. It may be readily understood that such cases as these are rarely 

 under clinical observation for a long time; the disease is found at the autopsy 

 in cases where death has occurred suddenly. 



Echinococcus of the blood-vessels and lymph-vessels as well as of the peri- 

 cardium is extremely rare. 



Echinococcus of the liver is the form most frequently met with. In the 

 Mecklenburg statistics they amounted to 69 per cent, of all observed cases, 

 in the Pomeranian statistics to 67.33 per cent. They are for the most part 

 unilocular, rarely multiple. They are found in all parts of the liver, but 

 most frequently in the right lobe. When centrally situated the cyst grows 

 but slowly, while echinococei peripherally situated give rise to great enlarge- 

 ment of the organ, even to six or seven times its normal size. The liver 

 substance is ruptured, and the cyst appears with single and multiple semi- 

 globular elevations upon the surface. If the echinococcus develops upon the 

 convex surface it forces the diaphragm far up into the pleural cavity, aud 

 causes compression of the lung and displacement of the heart. 



Occasionally the echinococcus penetrates the diaphragm and extends into, 

 or perforates into, the pleural cavity or the bronchi. When the cyst spreads 

 into the abdominal cavity, it causes displacement of the stomach and intes- 

 tines. It occasionally adheres to these organs, and, finally, ruptures into 

 them; or, in the absence of adhesions, it may perforate the abdominal cavity. 

 This is, however, rare. In such cases fatal peritonitis is the immediate con- 

 sequence, while with rupture into the stomach, intestines, etc., ultimate recov- 

 ery is possible. The paths which the echinococei may make for themselves 



are numerous. .14^ + 



Echinococei of smaller size often produce no symptoms, or, at least, not 

 for a long time. Usually only with increasing growth does the parasite mani- 

 fest its presence. Symptoms are at first local, such as a sense of pressure, 

 of heaviness, or occasionally pain. Frequently echinococei of considerable size 



