Streptococcus milleri Group Infection Associated with Digestive Fistula in Patients with Vascular Graft: Report of Seven Cases and Review

We described seven patients with Streptococcus milleri group aortic (six patients) or vena cava (one patient) graft infection secondary to a vasculo-digestive fistula. Time between vascular graft setting and first clinical signs varied from eight months to more than thirteen years. Six patients had fever. Three patients presented with recurrent fever for more than nine months and in two of these cases, delay before diagnosis was long because repeated blood cultures were sterile. Three patients had abdominal pain and/or digestive haemorrhage. Abdominal CT-scan S. milleri was not contributive for the diagnosis in four patients. Streptococcus anginosus was isolated in four patients, Streptococcus constellatus in three patients. One patient died before surgical management. The other six patients were cured by a surgical management associated with a prolonged antibiotic (lactams) treatment. S. milleri group graft infections are rare (or misdiagnosed) while we found only 4 similar cases in the English medical literature. We conclude that a peri-prosthetic infection secondary to a digestive fistula must be insistently searched (and blood cultures must be repeated many times) in any patient with an aortic (or any other vascular) graft presenting prolonged or recurrent fever or acute digestive symptoms.