Patient with a past history of renal calculi presented with left flank pain. His creatinine was found to be 700 umol/L.
Bilateral hydronephrosis was seen with bilateral echogenic, shadowing masses within the renal pelvi consistent with renal calculi
Ureteric renal stones are often not seen by ultrasound, especially in the mid ureter. Stones are more likely to be seen if they are at the pelvi-ureteric or vesico-ureteric junctions. Within the kidney, small calcifications may be due to stones or calcified vessels, and perinephric fat is often brightly echogenic which can mimic or mask stones. Larger stones are easier to see.
As such, the utility of ultrasound in renal colic is often to look for the secondary signs, such as hydronephrosis (including minimal dilation or "fullness" of the collecting system) and differences in ureteric jets. In addition, ultrasound is very useful in excluding abdominal aortic aneurysm as a differential diagnosis.
The patient underwent stent insertion and his renal function recovered.