Recent information regarding clinical leptospirosis in Europe is sparse in comparison with information about this disease in the United States and certain other countries. A retrospective study describing seven clinical cases of dogs diagnosed with leptospirosis on the basis of a MAT (Microscopic Agglutination Test), serology or autopsy at the Department of Medicine and Clinical Biology of Small Animals, Ghent University between Januarv 2003 and October 2005 is presented. All the dogs had non-specific clinical signs and presented with acute renal failure, with or without signs of liver insufficiency and/or bleeding tendencies. In the three dogs in which a MAT was performed, the highest antibody titers were found against Leptospira serogroup Pomona (n=2) and Javanica (n=1). It is recommended to treat every patient with clinical signs and laboratory abnormalities of acute renal failure without a known cause with penicillin derivatives until specific testing confirms or rules out leptospirosis.