[Retroperitoneal actinobacteriosis caused by Haemophilus actinomycetemcomitans]

A 15 years old boy was admitted to the hospital for high fever, and a four month history of abdominal pain and weight loss. Clinical examination showed painful swelling of the left lumbar region. A retro peritoneal mass was revealed by tomodensitometry. There was a marked biological inflammatory syndrome without bacteriological evidence of infectious disease. Final diagnosis was performed by surgery showing a big abscess. Bacteriological culture of pus was positive for a Haemophilus actinomycetemcomitans.