Supernumerary kidney
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
A supernumerary kidney is an additional kidney to the number usually present in an organism.
Pathophysiology
Supernumerary kidney often develops as the result of splitting of the nephrogenic blastema, or from separate metanephric blastemas into which partially or completely reduplicated ureteral stalks enter to form separate capsulated kidneys; in some cases the separation of the reduplicated organ is incomplete (fused supernumerary kidney).