Annular pancreas associated with diffuse chronic pancreatitis.

A patient with longstanding diabetes and renal failure presented with painless vomiting due to duodenal obstruction was found to have an annular pancreas. Initial operative evaluation, later pathologically confirmed, demonstrated involvement of not only the annulus, but also the entire gland by diffuse atrophic chronic pancreatitis. We speculate on the possible influence of the underlying diabetes and renal disease on the pathogenesis of the unusual generalized chronic inflammatory changes and the precipitation of duodenal obstruction in this patient.