Doctors can often see a large hiatus hernia on a chest x-ray. Otherwise, people are given barium in a liquid before x-rays are taken (barium swallow). The barium outlines the esophagus, making abnormalities easier to see. Hernias can also be seen during an upper endoscopy.
The kidneys filter the blood to remove wastes and produce urine. The ureters, urinary bladder, and urethra together form the urinary tract, which acts as a plumbing system to drain urine from the kidneys, store it, and then release it during urination.
Blood supplied to the kidneys goes through a complex filtration process in order to remove toxic waste products from the blood. Chief among these waste products are urea and uric acid. If too many of these waste products are allowed to accumulate in the blood stream, this will result in life threatening illnesses.