Try an enzyme cleaner like Nature's miracle.

I woke up last week to my cat pissing IN my bed, while I was still in it.
Blankets caught most of it but some did seep through to the mattress.  I
poured Nature's Miracle on the wet spots and then aimed a fan at it.  By the
time I got home from work, it was completely dry.  I have used this on the
mattress before, and the first time a lot of urine got through and it took a
couple of days to dry.  I put my nose right up to the area that had been
soiled, and I can't smell anything.  I'm sure my cats probably can, but to
me there's nothing noticable.

--
Liz

Home depot sells a powder called "capture".  Dampen the spot, scrub in
the powder, let it dry completely.  Vacuum out with an attachment or a
shop vac.  Repeat if needed.

If it happens again, dont use detergents, just sop up what you can with
paper towels, then use the capture.

Beth

Water and vinegar will do it.

Java