Q: How dangerous are kidney stones in a single kidney patient? My father is 70 years old. He has one kidney and has a previous history of stones. He had one last week. The doctors put a stent in his ureter, where the stone is, but there is another stone, which is not in the stent. Is he in great danger? He works out regularly and is in good health. The kidney was removed 10 years ago due to a small tumour, which was diagnosed very early and chemotherapy was required.

A:Kidney stones affect about 12% of men and 5% of women by the time they are 70 years old. Most of times, except causing pain, they do not result in significant morbidity. However, since you father has single kidney and has known history of stones, this issue deserves serious consideration. All steps must be taken to ensure that stones do not block the urinary tract which may lead to kidney failure. I am sure the urologist managing his condition must be looking into all aspects and therefore regular follow-up with your care-provider is very important. High Oxalate Foods to Avoid If you avoid the foods listed below you can reduce your oxalate intake. If you eat a large amount of foods on this list, eating less may be helpful.

• Chocolate
• Tea
• Spinach
• Beet tops
• Peanuts
• Almonds
• Pecans

• Dairy Products -For adults and children over 5
• Skim or 1% milk
• Low-fat yogurt
• Low-fat cheeses