Isolated kidney: The formation of the kidney requires the interdependence and complete development of the renal primordium located on the dorsal and lateral side of the body cavity before the embryo and the ureteric bud from the Wolffian duct. The absence of these two conditions will result in isolated kidney or renal hypoplasia. Bilateral renal hypoplasia or absence is rare. More common is unilateral renal hypoplasia or absence. Hypoplastic kidneys can cause back pain and hypertension. Venography shows that the outline and pelvis of the affected kidney are smaller and the contrast is blurred, often found incidentally. The clinical importance of unilateral renal hypoplasia or absence varies with the condition. If the other kidney has no other disease, it can maintain homeostasis and is often not discovered, but is often discovered when examined for other reasons. Imaging studies can confirm the diagnosis. It should be noted that in the treatment of kidney diseases, it is necessary to first determine whether the contralateral kidney is hypoplastic or absent, especially in the case of trauma, to avoid blindly resecting congenital isolated kidneys.
