408 DISEASES OF THE KIDNEYS 



The life cycle of the Dioctophyme renale is not entirely 

 known. The ovum is expelled from the body of the host, 

 and undergoes further development in water or damp soil. 

 It requires some time for these changes to take place (from 

 three to six months). The embryo may live and be active 

 after one year to eighteen months. The embryo is 240 

 microns long and 14 microns broad, cylindrical, and gradually 

 tapering posteriorly; the head is pointed, mouth terminal 

 and not provided with papillae, but with a small projection 

 which no doubt serves the embryo as an organ of penetration. 

 The intermediate host has not been fully determined. The 

 dog takes the embryo into the intestinal tract, where it 

 undergoes further development, and the embryo migrates to 

 the organs and tissues. It may also be introduced into the 

 urinary passages direct. The favorite seat is the kidney, 

 although it may be found in the abdominal cavity, liver, etc. 

 There still exists some doubt as to the exact method of migra- 

 tion of the embryo. 



The parasite after reaching its destination, develops and 

 produces marked changes in the pelvis of the kidney, and in 

 a number of instances completely destroys the organ. In 

 cases of early invasion there will be found inflammation with 

 hemorrhages, and purulent material. More advanced cases 

 will reveal a secondary inflammation with destruction of the 

 renal tissue, often transforming the kidney into a sac with 

 thick walls. The worm or worms will be found coiled up in 

 this sac. The number of parasites found will vary. In 

 most cases only one; in others two or more, even as high as 

 four have been found. 



Symptoms.— There may be no symptoms during life. In 

 a case of the author's in which four parasites were found, and 

 the renal tissue completely destroyed, the dog showed no 

 symptoms. The worms were found on autopsy. The animal 

 was in excellent condition and apparently in the best of 

 health. However, in some cases, symptoms are observed. 

 Severe pain, restlessness, nervousness and even rabiform 

 phenomena have been observed. The dog may show spinal 

 curvature due to pain on the affected side. The general 

 condition is often interfered with, the animal becoming 



