Pediatric Horseshoe Kidney

  • Etiology: Ascending kidneys hooked on inferior mesenteric vein leading to fusion of lower poles and anteriorly placed renal pelvis and ureters
  • Imaging:
    — Midline fusion of inferior poles of kidneys
    — Challenge is how to determine lengths of left and right kidney components
  • DDX:
  • Complications:
    — Prone to stasis or stone or infection or scarring
    — Ureteropelvic junction obstruction
    — Increased risk of bleeding secondary to blunt trauma due to isthmus anterior to spine
    — Increased risk of cancer
  • Treatment: None
  • Clinical:

Radiology Cases of Horseshoe Kidney

CT of horseshoe kidney
Axial (above) and coronal (below) CT with contrast of the abdomen shows the lower poles of the kidneys to be fused in the midline. There is mild hydronephrosis of both kidneys.
CT of horseshoe kidney
Axial CT with contrast of the abdomen shows the densely enhancing lower poles of the kidneys to be angulated medially (above) and to eventually fuse in the midline (below).
US and MAG3 scan of horseshoe kidney
Transverse midline US of the lower abdomen (above) shows renal parenchymal tissue in the midline just anterior to the spine representing the fused lower poles of both kidneys. MAG3 scan (below) shows radiotracer uptake in the bilateral kidneys as well as in their fused lower poles.