Hi
I cant be sure from what you describe but it is possible she has some congenital abnormality i.e she was born with a urinary system that is not normal and so leaks all the time. One such example of this would be a condition called an ectopic ureter. This is an abnormality of the tube that normally runs from the each kidney to the bladder and it ends in an abnormal location. The cure is surgical and the ureter needs to be relocated into the bladder. That is a complicated specialist piece of surgery but often successful. I would expect your vet could refer your dog to a specialist for a further assessment for this.
Cathy Wickenden BVet Med MRCVS
Barton Lodge Veterinary Centre
1 Midland Road, Hemel Hempstead, Hertfordshire, HP2 5BH
Tel: 01442 216048 24 hours
[
www.bartonlodgevets.co.uk]