A 57-year-old man presented with periodic arthralgias, myalgias, fever and clubbing of his toes. On the basis of skeletal scintigraphy and radiological examinations he was diagnosed with hypertrophic osteoarthropathy (or Pierre Marie-Bamberger syndrome). Elaborate diagnostic work-up did not reveal any underlying cause, specifically no pulmonal abnormalities, malignancies or infections. Only when he later presented at the accident and emergency department with signs of an upper gastro-intestinal bleeding, did a new CT scan reveal an aorto-enteric fistula caused by aortic graft infection. The infected vascular prosthesis was surgically replaced and a duodenal defect was closed. Sepsis and multiorgan failure occurred postoperatively, from which the patient largely recovered. At follow up, scintigraphic re-examination of the bones showed that the hypertrophic osteoarthropathy associated with the periost reactions had almost disappeared completely, and the clubbing of the toes was less. One of the rarer causes of clubbing toes and watchglass nails is infected vessel prostheses, as illustrated by this case. In patients with hypertrophic osteoarthropathy and symptoms of general malaise rarer or unusual causes should also be considered in order to prevent a severe complications.