Supernumerary kidneys- a rare anatomic variant

Abstract

Supernumerary kidneys are a rare congenital anomaly with fewer than 100 cases reported over the years. A fused supernumerary kidney is a still rarer entity. We present imaging findings in two cases of supernumerary kidneys--the first case is a spectacular image of four kidneys in one patient seen in an excretory phase of intravenous urogram with only four cases described in the literature. The second case is that of three kidneys (fused supernumerary) seen in another patient.

Ectopic supernumerary kidney. A casual finding

“…2,3 In our case there was no evidence of alterations in any of the studies carried out in relation to possible associated complications and/or congenital anomalies. Very few cases have reported congenital anomalies associated with the presence of 3 kidneys.…”

Computed tomographic and sonographic findings in a dog with duplex kidney, ureter duplex and ectopic ureterocele

“…If the renal parenchyma is completely or incompletely separated into 2 parts, the anomaly can be described as supernumerary kidney [3] [18]. The supernumerary kidney is also defined as having a separate arterial and venous drainage sometimes with a separate capsule.…”

“…Both poles of the malformed kidney were drained by a collective vascular supply and surrounded by a single continuous capsule with a fibrous band dividing the 2 poles. Given the fact of a common vascular supply, the most accurate term for the renal malformation in both cases might be a bilobed duplex kidney [18] [19].…”

A rare case of supernumerary fused and malrotated kidney

“…It is a very rare type of congenital renal anomaly with fewer than 100 cases reported since firstly described at 1656 (1). Embryological basis of supernumerary kidney is connected to the abnormal division of the nephrogenic cord into two metanephric blastemas which will form two kidneys (2).…”