Congenital hydronephrosis in a crossbreed puppy

A six-week-old female Golden Retriever crossbreed was presented with abdominal distension. Palpation of the abdomen revealed an abdominal mass. A radiographic examination showed a swelling in the region of the kidneys, so ultrasonographic examination was performed and revealed a severe hydronephrosis of the left kidney. The right kidney and serum biochemical analysis were not markedly changed. Hydronephrosis always occurs secondarily to a partial or complete urinary tract obstruction. In this case, there was an ureterovesical junction obstruction (UVJO), which seemed to be idiopathic. Due to the severity of kidney alterations and the young age of the puppy, the anomaly was thought to be congenital. There are a few case reports about congenital hydronephrosis and its causes in veterinary literature. This article gives an overview about embryonic development and current knowledge in human medicine. The affected left kidney was removed and the bitch was spayed without any complications. The patient was released with an optimistic long-term prognosis. Unfortunately, she suddenly died three months after the operation. As the owners did not allow a post mortem examination, any thoughts about the cause of death remain purely speculative.