Renal colic

Renal colic, also known as ureteric colic, is a type of abdominal pain commonly caused by obstruction of ureter from dislodged kidney stones. The most frequent site of obstruction is the vesico-ureteric junction (VUJ), the narrowest point of the upper urinary tract. Acute obstruction and the resultant urinary stasis (disruption of urine flow) can distend the ureter (hydroureter) and cause a reflexive peristaltic smooth muscle spasm, which leads to a very intense visceral pain transmitted via the ureteric plexus.