A case report of Dioctophyma renale infection in a stray dog from Tabriz city, Iran

Introduction: Dioctophyma renale is one of the most important members of the family Dioctophymatidae, known as Giant Kidney Worm due to its large size. Infection to this nematode is occurred in a wide range of mammalian types and most of the climate in the temperate regions of the world. Infection reports of wild carnivorous, domesticated dogs and also sporadic reports of abnormal hosts such as humans are available. Case report: In the fall of 2015, a mixed race, male, adult (approximately 5 years old) and stray dog was purchased to the anatomy laboratory of the department of the basic sciences of the faculty of veterinary medicine, University of Tabriz, Iran. After dissecting and handling the internal organs, the right kidney appeared to be abnormal at the anatomical and histological features. To find the etiology, a longitudinal cut was taken to the involved kidney and it was found a large hank of worm inside of kidney. Immediately, the cut kidney was transmitted to the department of Parasitology. After isolating and measuring the dimensions of the worm and scrutinizing the important characteristics of the parasite morphology, the findings were: the presence of one brownish-red nematodes with 38 cm in length, 6 mm in width and a massive destruction of the kidney wall remained a thin layer of kidney parenchyma. After comparing the morphometric and morph anatomic characteristics with valid keys, the parasite was diagnosed as Dioctophyma renale. It should be noted that the animal was relatively skinny and because it had been merely purchased to be dissected, so, the clinical and laboratory examinations were not performed. Conclusion: Up to now, this nematode has been chronologically reported from donkey (Kerman), stray dogs and jackals (Tonekabon), human (East Azerbaijan Province), domestic dogs (Fuman and Tehran), fox (Caspian seashore) and recently from a dog (Hamadan) in Iran. By looking for the literature, the infection to this nematode is still present in Iran, and most findings are resulted as case or accidental reports. Therefore, a large-scale field survey seems to be necessary at least on the population of Iranian dogs.