[Excruciating flank pain: "acute renal colic"].
The classic presentation of acute renal colic is the sudden onset of very severe pain in the flank primarily caused by the acute ureteral obstruction. The diagnosis is often made on clinical symptoms only, although confirmatory exams are generally performed because many others significant disorders may present with symptom of flank pain that mimics renal colic. Life threatening emergency such as abdominal aortic aneurysm must be ruled out. While non contrast CT has become the standard imaging modality, in some situations, a plain abdominal radiograph associated with a renal ultrasound or a contrast study such as intravenous pyelogram may be preferred. Hematuria is frequently present on urine analysis. The usual therapy represented by analgesic and nonsteroidal anti-inflammatory drugs should be started as soon as possible. Size and location of the stone are the most important predictors of spontaneous passage. Uncontrolled pain by medical therapy, fever, oligo-anuria suggest complicated stone disease. Such conditions require emergency treatment by drainage or stone extraction. Although recurrent stone rate is important, extensive metabolic explorations are not recommended after an uncomplicated first episode. Nevertheless fluid intake is encouraged and a stone chemical analysis should be performed whenever possible.