Abstract / Summary
Background/Objectives: Renal hypoplasia is the reduction in renal mass due to inadequate kidney development or blood supply. It is one of the more frequently misapplied terms in renal pathology, and it includes simple, oligomeganephronic, segmental, and cortical subtypes. Congenital anomalies of the kidney and urinary tract affect an estimated 1 in 500 live births. Few cadaveric studies have documented vascular anomalies, such as accessory renal arteries, thoroughly. This cadaveric case report aims to characterize the gross and histologic features of a markedly reduced left kidney size and compensatory enlarged right kidney encountered during routine cadaveric dissection, with attention to an accessory right renal artery arising from the common iliac artery. Methods: This cadaveric case report was conducted on a 95 year old male whole-body donor. Kidney length, width, depth, and weight were recorded bilaterally and compared to normative cadaveric datasets. Renal arteries and renal veins were measured for length and width. Ureter width was also noted. Coronal sections of both kidneys were examined. Hematoxylin and eosin-stained histologic sections of both kidneys were reviewed microscopically to characterize nephron architectures, tubulointerstitial changes, and glomerular status. Renal arteries were also analyzed histologically for atherosclerotic changes. Results: Bilateral kidneys were identified in their expected anatomic positions with marked size differences. The left kidney measured 6.0 cm in length, 1.8 cm in width at the mid-hilum, and 2.0 cm in depth at the mid-hilar level. The left kidney weighed 18.6 g. The right kidney measured 13.5 cm in length, 6.0 cm in width at the mid-hilar level, and 5.0 cm thick at the mid-hilar level. The right kidney weighed 155.3 g. The left kidney was supplied by a single renal artery and vein, while the right kidney demonstrated dual arterial supply. A primary right renal artery from the abdominal aorta and an accessory right renal artery from the right common iliac artery supplied the right kidney. The right ureter was mildly dilated compared to the left. Gross coronal sections of the left kidney showed defined renal pyramids and columns despite reduced size. The right kidney showed poorly defined pyramids and columns, dilated calyces, and multiple cortical cysts. Histologically, the left kidney showed normal architecture of intact nephrons with reduced overall number of functional units consistent with favoring simple hypoplasia. The right kidney showed diffuse “thyroidization” with interstitial inflammation, tubular atrophy, and glomerulosclerosis. Conclusions: This case documents marked anatomic and histologic asymmetry between paired kidneys alongside a congenital accessory renal artery arising from the common iliac artery. Identification of anomalous vascular supply, such as an accessory renal artery arising from the common iliac artery, is clinically relevant to surgical planning.