1Department of Clinical Sciences, Faculty of Veterinary Medicine, Karaj Branch, Islamic Azad University,
2Department of Pathobiology, College of Veterinary Medicine, Lorestan University, Lorestan,
3Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Tehran,
Concurrent disorders with diabetes mellitus is one of the most challenging subject. Our knowledge of the most common concurrent disorders in diabetic dogs may be useful in diagnosis of these disorders and better treatment of diabetic dogs. In this study diabetes mellitus was diagnosed in a 7-year-old male German shepherd dog, based on clinical and laboratory findings. Following the diagnosis of diabetes mellitus, insulin therapy was started and blood glucose concentration reached to the accepted level. Eleven months later the dog was presented again with acute episodes of collapse and hypoglycaemia. The owner noted that there was no change in the animal’s routine insulin treatment programme and the dog had received his daily insulin injections. Further ancillary diagnostic tests were refused by the owner and the animal was humanely euthanized. Histopathological diagnosis was correlated with lymphoma. The association between diabetes mellitus and lymphoma has been reported in human medicine but the similar clinical condition has not been reported in veterinary literature.