CYSTIC DISEASE OF THE URINARY TRACT IN MAN 75 



Lubarsch 1 has attributed the formation of the cysts to degeneration 

 of these. This hypothesis does not account for the presence in the 

 cysts of the kidney of bodies and material similar to those found in 

 the ureteral cysts, nor does it account for the intense inflammatory 

 action, accompanied by cyst-formation, at the neck of the_ bladder. 

 The view that the bodies in the cysts of the urinary tract were 

 protozoa appears to have originated with the late T. S. Cobbold, 

 formerly well known as helminthologist to the Middlesex Hospital. 

 Cobbold's view was recorded by the late W. B. Hadden (Trans. 

 Path. Soc., vol. xxxiv., p. 237). The contents of some sub- 

 capsular renal cysts that occurred in a case of multiple sarcoma 

 were submitted to Cobbold, who pronounced them to be ' psoro- 

 sperms,' and there was in the Society a tradition to the effect that 

 Cobbold regarded certain bodies in the sarcoma-tissue also as 

 psorosperms. I never thought that the oval bodies were coccidia in a 

 strict sense, but I did come to the conclusion that not only the oval 

 and other bodies, but also the albuminous material in which they 

 are embedded, were sporozoa of some kind. The late von Kahlden 2 

 regarded them as myxosporidia. It must be confessed that the 

 colloid-like basis of the cyst-contents, with the contained bodies, as 

 shown in Figs. 22 and 26, bear a resemblance to some of the myxo- 

 sporidia. On this supposition the whole contents of a cyst would 

 be one amoeboid myxosporidian and the oval bodies pansporo- 

 blasts. But the typical spores of the myxosporidia are wanting. 

 Without arguing the matter in further detail, 1 may say that I still 

 regard the whole of the cyst-contents, together with the oval bodies, 

 as protozoa ; and this for many reasons, two of which are first, 

 the improbability of any process of degeneration being capable of 

 causing both nucleus and cytoplasm of the cells lining the cysts 

 to swell equally to form the large oval bodies ; and, second, 

 the evidence that both the oval bodies and the albuminous sub- 

 stance subdivide into smaller amoeboid bodies, such as are 

 shown in Fig. 25, a. To what class of the protozoa they should 



1 Lubarsch, Archiv.fur Microskop. Anat., 1893, P- 33- 



2 Von Kahlden, Zeigler's Beitrage, 1894. 



