[Crossed renal ectopia discovered incidentally: about one case report].

Crossed renal ectopia is a rare congenital abnormality, in which the two kidneys are located in the same side. One of the ureters, whose length is adapted to the kidney seat, crosses the median line to implant in the bladder on the opposite side. Renal fusion of the two parenchymas is common and this abnormality is most often asymptomatic and fortuitously discovered. We report the case of a 36-year old patient with no previous pathological history, presenting with crossed renal ectopia incidentally discovered after acute cholecystitis complicated by perivescicular abscess. On the basis of this observation and of the data from the literature, we here discuss the etiopathogenic, clinical, radiological and therapeutic features of this malformation.