What advice do you offer to patients with recurrent nephrolithiasis who are on a tube feeding diet and seeking stone prevention guidance?

As always, it is important to know their stone composition, so that you tailor the invention appropriately. Regardless, I have seen many such patients with calcium oxalate stones. It is important to get detailed information about their tube feeding formula and dosing, because tube feedings can vary quite substantially in their nutrient content, as well as oxalate content. The University of Wisconsin group has published oxalate contents of many common tube feeding formulations (Kristina Penniston is one of the authors), so frequently a change in the product used can make a substantial difference. Absent finding their particular product in that article, I favor whey based products over soy or nut based (typical protein sources) to avoid high ...

That is an interesting question. I do not remember encountering such a patient. The first thing I would like to know is the composition of the patient's previous stones. I would then work with my nutrition colleagues to modify the tube feedings to make the urinary milieu unfavorable to that stone type. If the stone type is unknown, I would simply increase the fluid content of the tube feedings to provide an intake of fluid to a minimum of two quarts.

Stephen B. Erickson, MD