The abdominal parasite Dioctophyma renale infesting the kidneys of dogs is known as the Giant kidney worm. They are among the largest internal parasites. The Giant kidney worms can grow up to 40 inches in length, even though the male worms are not as big as the females. The worms have blood-red color, and their eggs are brownish yellow and barrel-shaped. They are excreted along with the urine. Giant kidney worms are not commonly seen in pet dogs.
Dogs may get infected when they eat raw fish or frogs infected with these worms. When these are digested, and their remains reach the bowels of the dogs, the worms leave the bowels and make their way into the liver first and from there to the kidneys. If they do not reach the kidneys, they may just remain in the abdomen.
The worms may cause widespread destruction and tissue damage to the affected kidneys, in addition to causing severe blockage. The infection is more frequently seen in the right kidney. However, if it occurs in both the kidneys, it may lead to total kidney failure. The infestation within and outside the kidneys may also result in liver disease as well as inflammation and scar tissue development in the abdominal cavity. The scar tissue may appear as bands in the intestines. The dog may have pain in the abdominal area and where the kidneys are located. Other common symptoms include weight loss and increase in urination with traces of blood found in the urine.
The presence of the eggs of Giant kidney worms in the urine is a sure indication of this parasitic infestation. X-rays and ultrasound scans may help diagnose the disease in case the eggs are not observed in the urine. They can help determine the extent of damage also. Occasionally, exploratory surgery may be done to identify the infestation in the abdomen. If only one kidney is infected, the best option is to remove that kidney. The dog can live a normal life with the remaining kidney if it is healthy. The infection can be prevented by not allowing the dog to catch animals which may be carrying these parasites and preventing them from eating them raw. Apart from frogs and fish, certain worms, including earthworms, can pass on this parasitic infection to dogs.