Dear mmkhan
Sorry to see your mother is having such troubles.
It is extremely difficult to find proper remedy via the internet postings.
Some remedies that help kidney are cantharis,berb.v,cal carb. apis
In Ayurveda there is a mineral pitch called ' shilajit' that may help.
Also drinking much watermelon juice pure pressed by hand.
The sores can be helped via external application of calendula ointment.
Calendula is a homeopathic remedy but in this case it comes in a topical gell,creme.(made from marigold flowers you have many in india)

I have given you dr. Banerjea's email address he has many clinics in india have you contacted him?

The internet posting of suggestions is not a proper method of treatment mmkhan,i know you are trying to help your mother but she is in a critical time of illness,please be carefull not to waist time by experimentation.
My urgent suggestion is to take her to a classical homeopath ,if important organs are failing that is not a good sign !!!!!!!!!!!!!!!!!!!!
Best to you
Gina Tyler