I don't mind answering. I gave the simplified version. Her body would not accept nutrition via the stomach, the upper intestine (jejunum, a J-tube) or intravenously (TPN). While the doctors were unable to diagnose anything more than gastroparesis (think "gastric paralysis") we (the family) suspect that there was a deeper systemic problem that the medical system would never have caught. Perhaps she had a disease that is extremely rare or as yet unidentified. Everything about it was atypical.
Right. It was so weird to see her get sick every time she started a bag of TPN. They tried different formulas, even exotic ones from overseas that were new to the market (and very costly).
My theory is that her body rejected nutrition in general and that the gastroparesis was just a symptom rather than a cause.
I've got a truly crazy level of food sensitivities and my mother was just about as badly off--and that makes me think of a slightly different theory that has worried me and I suspect applies to your wife:
Rather than rejecting nutrition in general the scenario that concerns me is reacting badly to something essential. All it would take is one component, not all nutrition.
To date I have reliable sources of carbohydrates and amino acids, but fatty acids are another matter. I have never found a source of highly purified fatty acids and as far as I can tell not even the TPN formulas are made that way.
I don't have gastroparesis issues but while AFIAK it was never labeled that my mother would react that way to eating something wrong. I can easily picture her getting sick from TPN containing something she was sensitive to.
It's not something that would have been of much priority for the doctors to test--if you can't tolerate all of the ingredients there's no value to knowing you can tolerate some. As far as I can tell your survival time eating no fat is a lot less than your survival time not eating, period. (If you're not eating your body draws on fat stores, thus providing fat. If you're eating but no fat the body doesn't draw on fat stores and bad things happen.)
