Renal disorders in newborns can be congenital or acquired. They are detected prenatally in about 1% of fetuses by ultrasound and in newborns by physical exam or autopsy in less than 1% and 7-9% respectively. Early diagnosis is important to prevent complications. Prenatal diagnosis is usually by ultrasound detecting signs of obstruction. Clinical manifestations vary by type and severity of abnormality and can include dysmorphic features, abdominal masses, ascites, failure to palpate kidneys, and hypertension. Acute renal failure is defined as a creatinine over 1.5 mg/dL and can be functional, intrinsic, or obstructive in nature. Causes include inadequate perfusion,