"Such things are rarely looked at together. Neuros rarely see people with PA/B12def and don't recognised it. Coeliac is rarely looked at by neuros though it can cause some crossover symptoms. Gastric imbalances get referred to a gastro specialist, and cognitive problems are rarely traced "

Agree totally. Medical practice is so compartmentalised.
I have gone gluten free since diagnosis 3 months ago. I have had gluten intolerance for years and it lead to leaky gut syndrome and low B12 levels. I recently started on high doses of B12 along with coconut oil. Have experienced big improvement in all aspects of my PD symptoms since doing this.