I have kidney infection for about 1,5 year. For me most usefull were not many water - only 0,5-0,8 litre per day, no garlic, no onion, no radish, no broccoli and all cabage family in raw, only very well cooked, because they irritate kidney. No orange, no lemon, grapefruit and all citrus fruits and NO VITAMIN C and multivitamins with vitamin C!!!! because vitamin C irritates kidney!!!
You can try to eat only buckwheat all day, 2-3 days per week with 0,5 l parsley or horsetail tea, and after this day you will notice that your kidney responsive to food and some supplements ... so don't use in this buckwheat days even all supplements, except vitamin D because maybe some of them irritate kidney.
Also essential vitamin D (if your situations worsen, try larger doses - 10000 vitamin D per day), NAC (2*600 mg per day) (for my kidneys it's a miracle), necessary to stengthen immunity (one month echinacea, other month astragalus, siberian ginseng etc.) Q10
I don't eat meat and dairy, so I don't know if my kidney liked them or not, but sometimes I eat fish and eggs and my kidney like them. Also my kidney like apples.
My kidney didn't liked Pau'd'arco. I tried it for immunity, but two times after taking one capsule 500 mg, my kidney were in pain. Also be very careful with species - turmeric OK, but black pepper NO. Cloves - OK, ginger - OK.
For my very useful site for supplements is http://www.lifeextension.com/Protocols/Kidney-Urinary/Kidney-Health/Page-08
In this site I learnt about NAC and tried it. For my kidney NAC was very very useful - like miracle cure. Thanks to God. I bought the cheapest NAC from iherb.