My indoor cat poops all over the house

My 16 year old cat has gotten progressively worse pooing around the house. She goes to the bathroom on everything almost 3 times a day and smears the poo. She will use the litter box to pee, not poop, and only 3 years ago always used the box for everything and we use the same litter.
She does have kidney issues so I don't know if it's related. When she goes her butt gets swollen and dark pink, and we just had her in the vet for all anal gland gunk she expressed a week ago and was doing fine until this week. The vets said nothing about her going on the floor. I thought she had constipation but whether the poo is hard or soft she goes to the bathroom wherever she is sitting and rubs her butt on the floor as she is going which is ruining the house. I'm out of ideas what to do as she is getting worse and the vets haven't helped!

Cats with CKD are prone to constipation, which may explain why she's scooting and/or not using the box. Talk to your vet about adding a stool softener like miralax to see if that helps. Also what foods are you feeding her? Low phos wet foods? You could also add some probiotics to her food that should help with stool issues too. 

I agree completely with Missmimz.  I've had 3 kidney cats, and when they are constipated, they will keep trying to go wherever they are...in the box, or anywhere else in the house.  AND, they will scoot to try to help it along, or to clean off any hard little marble that might be stuck halfway out.  Believe me, been there.

The best thing we ever did was to start feeding an all wet diet with extra water added, AND add in a little bit of miralax twice a day.  Our Vet told us how much to use.  Once we did that, all constipation issues resolved and no more little "presents" were left around the house. 

Dry or moist poo, she always scoots across the floor. She gets dry and wet food but mostly eats wet, I've been giving a probiotic, and found out the hair ball treats I give cause her to go softer stool. She used to have loose stool constantly before her kidney issues now it's the opposite!

I have to look into kidney food if she will eat it.

When cats get older, moving around/ getting in the litter box gets harder. Maybe try putting more litter boxes around with lower sides so it's easier for her to get in/out. Also, do you have any other cats that might might be blocking her from entering into the litter box?

No cats blocking her from going in and like I said she pees in the box just fine.