Presentation
Work up for hematuria.
Patient Data
The lower poles of both kidneys are seen pointing medially and fused across the midline by an isthmus of functioning renal tissue, with anteriorly malrotated hila denoting horseshoe kidneys. Normal parenchymal thickness and density of both kidneys are evident.
A 23 mm stone (330HU) is present at the right renal pelvis, and a 13 mm stone (339HU) is evident at the left renal pelvis, causing mild hydronephrosis. Additionally, a 15 mm simple cortical cyst is noted at the left kidney.
Smudging of the fat planes is seen surrounding the superior mesenteric vessels and their branches within the root of the small bowel mesentery, accompanied by several prominent mesenteric lymph nodes, most compatible with mesenteric panniculitis.
The hepatic attenuation value is less than that of the spleen, suggesting fatty liver.
A peripheral, dense, spotty enhancing mass, approximately 90×75 mm in diameters, is seen at the right liver lobe, on early post contrast phase. In the equilibrium phase, the attenuated areas spread through the mass and fill in. Features are most compatible with hemangioma.
Case Discussion
Horseshoe kidneys are the most common type of renal fusion anomaly. They render the kidneys susceptible to trauma and are an independent risk factor for developing renal calculi and transitional cell carcinoma of the renal pelvis.