I just Googled this and saw a link to similar symptoms and those jerky treats from China! Has your friend been feeding these?
There is an excellent email list at Yahoo for kidney diets which would be helpful if your friend is prepared to give home-made meals to this dog. It's called K9KidneyDiet.
I fed the Turkey Jerky Treats about 4 years ago to my dog and he just about died. He walk was very weak. I rushed him to the Hospital and they started running tests. They have their own equipment.
He was in liver failure from a massive infection. They took him right in and started treatment. He was in the Hospital for about a week and then back to his ole self.
He is fine now and went on to complete his Championship. At the time it happened the Vets didn't know if he would make it.
I didn't know then they were shipping food from China. I won't eat or feed anything from there and read all of the labels. The new China labels are very fine and some vendors sat packaged in the USA. I won't buy from them either.
You might consider having your Vet run an ACTH Stim test to check for Addison's Disease. I have an Addisonian dog and his first symptoms started out with elevated kidney values....just a thought.