Fetal accessory renal arteries and other renal anomalies

Background: Human kidneys develop from intermediate mesoderm, in three successive stages; pronephros, mesonephros and metanephros. The definitive kidney, which is derived from metanephros occupy sacral region initially, which ascent later, reaching the adult position by 9th week. It receives blood supply from different sources during its development and ascent. Accessory renal arteries are widely studied in adults while the same in fetuses is an understudied topic. Aims and Objectives: The present study was carried out to find out the percentage of accessory renal arteries in fetuses and associated positional congenital anomalies with it. Materials and Methods: Fifty fetuses of gestational ages ranged from 14 to 40 weeks were collected from the department of Obstetrics and Gynecology, with prior permission from Head of the department and Dean. Results: The study showed a higher percentage of accessory renal arteries in fetuses (30%) and in 2 out of 50 fetuses dissected (4%), accessory renal arteries were found to be associated with positional anomalies. One was a case of bilateral ectopic kidney whereas the other was a horseshoe kidney (HSK). Lobulation were seen in most of the kidneys and 3 cases of bilateral accessory renal arteries without any obvious anomalies were noted. Conclusion: As the advancement in prenatal diagnostic techniques, screening for accessory renal arteries in fetuses can provide a clue for associated congenital renal anomalies. Knowledge on vascular variation in fetuses will help pediatric surgeons in planning abdominal surgeries in new born and children of early ages, where vascular anatomy may be different than in adults.