No, nothing about kidney. Otherwise there could be some symptoms in urine..burning..urethral pain, nausea etc Seems acid reflux and that opinion strengthens. Coating has responded. Diarrhoea is due to Mandagni as also white tongue. I would say to my own patients to use herbs Bilva and Kutaja powders. These are not palatable but if you give mixed in yogurt or curd or buttermilk with a pinch of roasted cumin seeds powder ( optional for better results), twice a day, you will see results in a week. It will cleanse intestines of accumulated mucous and improve appetite and digestion. Drink warm water. Capsules of these herbs are also available globally. Two caps each may be poured in yogurt etc. For reflux additional Avipattikar powder may be given with water. It s bitter but fruitful. Once diarrhoea is controlled and appetite normal, no need to try for hydration. It will be automatically. All minerals will be replenished with these herbs. May be slow. But effective. These pure herbs are safe, economic and no side effects. It will correct back pain to some extent too. Otherwise massage with some liniment locally. Hope it will help you. Otherwise option is open for you to switch to toxic drugs and troublesome procedures. Wish your husband natural recovery.