Medizinische Klinik, Kantonsspital, Luzern.
Although excess fat deposition in the omentum and obesity have been suggested as possible predisposing factors for omental torsion, no previous descriptions of an association between the Prader-Willi syndrome and omental torsion have been found in the literature. We therefore report the case of a 6-year-old boy with Prader-Willi syndrome and primary torsion of the greater omentum.