A renal scan is an examination that uses small amounts of radioisotopes injected into the bloodstream followed by the scanned images of the kidneys which are analysed by the computer to evaluate how well your kidneys are working. The test evaluates the size, position, shape, and filtering function of the kidneys.
Reflux is usually a congenital condition when urine goes back up the wrong way from the bladder towards the kidney, while the bladder is emptying. Often, people are unaware of its underlying presence though many times it results in recurrent urinary tract infection and injury to kidneys. If kidneys do get affected, this probably occurs very early in life, and possibly before birth. Sometimes, children with reflux kidney disease may have other abnormalities within the kidney or lower down- for example, impaired development of kidneys or narrowing or blockage of the urinary tract. Besides renal scan, one could perform a test called “micturating cystourethrogram”. It involves insertion of catheter into the bladder followed by injection of contrast liquid through the catheter into the bladder that will show up on X-ray pictures taken during urination effectively diagnosing presence of reflux disease. However, it doesn't give information about underlying kidney function. Many times, a congenital multi-cystic disease of kidneys is accompanied by an underlying reflux disease. Hence, it is important to evaluate the function of both the kidneys and also study the anatomy of urinary tract at an early age before planning further management. Both the procedures mentioned are safe enough to be performed at the current age as advised by your child’s doctor. The amount of radioactivity material injected for renal scan is no more than one receives getting a standard X-ray.