- most common renal anomaly
- risk factor for kidney stones and transitional cell carcinoma of renal pelvis
- vast majority cases are sporadic
- frequently associated with many genitourinary abns and chromosomal conditions eg Down’s syndrome
- Usually asymptomatic, symptoms when there are eg kidney stones.
- formed by fusion across the midline of two distinct functioning kidneys at lower poles.
- They are connected by an isthmus.
- The normal ascent of the kidneys is impaired by inferior mesenteric artery (IMA) which hooks over the isthmus
- No treatment required and patient has normal life expectancy.