Polycystic kidneys: A reader last time wanted to know more about this disease. It's a disease where cysts grow in the kidneys, with symptoms of abdominal pain and blood in the urine, one reader responds. It could be hereditary, although one reader says that her sister's daughter has not developed them, so that may not be so. One reader is on diuretics, which seem to control the problem. A self-help approach is to avoid caffeine, suggests another reader, as this can increase the growth of the cysts. Another says that you should avoid excessively hot or spicy foods.