536 THE ANIMAL PARASITES IN MAN 



the characteristic lobulated tumor disappears. Decided displacements of the 

 organs of the neck may develop in such cases. Confusions may arise from 

 echinococci which are situated in the muscle itself or that have developed in 

 the thyreoid gland. In three cases after successful extirpation death resulted 

 from secondary hemorrhage. 



Echinococcus of the thyreoid gland is rare. Henle reports 18 cases ; in 

 three other cases the diagnosis is questionable. Vitrac has collected 31 re- 

 ports of echinococcus of the thyreoid. Another case is reported by Posadac. 

 The echinococcus is usually unilocular and may attain the size of a fist. In- 

 creasing growth causes atrophic conditions of the glandular tissue. The con- 

 sequences of displacement, that is, compression, of the neighboring organs, 

 in which particularly the trachea, the esophagus and the recurrent laryngeal 

 nerve are to be considered, may be serious. Suppuration of the cyst is fre- 

 quent. The sac surrounding the echinococcus becomes adherent by inflamma- 

 tion to the adjacent areas, and these are to a certain extent involved in the echi- 

 nococcus sac, so that this represents only a part of the echinococcus. This 

 enlargement results in increased erosion of the surrounding areas in which the 

 trachea particularly may be implicated. Adhesions to the muscles and the 

 skin are less frequent. The echinococcus grows very slowly. Its form is usu- 

 ally globular. The difficulty in respiration which occurs, to which difficulty 

 in deglutition and paralysis of the recurrent laryngeal nerve may be added, 

 causes the patient to consult a physician. The diagnosis can rarely be made 

 with certainty. Early operation improves the prognosis decidedly. Accord- 

 ing to Henle wide opening of the sac is most frequently advisable, as enuclea- 

 tion is often very difficult. If this operation be attempted, it is not always 

 possible to spare the recurrent laryngeal nerve which may be situated in the 

 wall of the sac. 



A case of echinococcus of the larynx has been described by Schiissler. 



Primary echinococcus of the pleura is rare. Maydl and Winzerling have 

 collected 30 cases from literature. In these the echinococcus was situated 

 either between the pleura pulmonalis and the costal pleura, in the pleural cav- 

 ity, or external to the pleura costalis. Much more frequent are secondary 

 pleural echinococci which have ruptured into the pleural cavity from neigh- 

 boring organs. 



The echinococcus is usually found upon the right side, surrounded by a thin 

 wall of connective tissue. It generally attains great dimensions. In the 

 main the symptoms differ but little from those of a pleurisy with effusion. 

 The patients complain of stitch in the side and an irritative cough, accom- 

 panied by scant mucus expectoration. Fever is absent. If the echinococcus 

 is large it leads to dilatation of the affected side of the thorax, frequently giving 

 a flaring shape to the lower part of the thorax, with retardation or immobility 

 m respiration. Percussion reveals a more or less extensive area of dulness, 

 frequently bow-shaped. Absence or diminution of the respiratory murmur 

 and of fremitus is noted; occasionally bronchial respiration is present. In 

 small cysts egophony and bronchophony are observed. Neisser quite prop- 

 erly emphasizes as characteristic the conspicuous proximity of normal and 

 abnormal auscultatory phenomena. In right-sided disease, the liver is dis- 



