A 5-month-old female Rottweiler was referred because of a 5-week diarrhea and a sudden onset of a cardiac murmur auscultated by its veterinarian. Definitive diagnosis of bacterial endocarditis was based on ultrasonographic visualization of vegetative cardiac lesions and positive cultures of Enterococcus faecalis in blood and urine. Complicating findings were suppurative nephritis and renal infarction. Despite intensive supportive care, the endocarditis and clinical condition deteriorated and the dog had to be euthanized.