[Diagnosis of a retroperitoneal BCG abscess in an infant. Case report and review of the literature].

We report on a Tunesian boy who was 1 year and 9 months of age and suffered from a large retroperitoneal Bacillus Calmette-Guerin (BCG) abscess. We specially emphasise the accurate diagnosis achieved by the interpretation of the sonographic results in association with the patient's anamnesis. The outcome of abdominal x-ray and contrast-enhanced CT is outlined. The diagnostic approach as well as the disease are described with reference to the literature.