Icontinence of urine and skin color change

Barney my 11year old westie has over the last few months start dribbling urine. To an extent that I have had to stop letting him upstairs and on the bed. - he obviously can't understand why all of a sudden there is a gate stopping him going upstairs. Thank God I have wooden floors downstairs. It doesn't happen all the time, but sometimes when he gets up from laying, there can be a damp patch or even alittle puddle. Took him to my vet - urine fine - no infection - bloods done - slight rise in liver function but otherwise ok - now going in for ultra sound and further bloods as now quering cushings disease, or bladder tumor or stone. he is also quering thyroid probs as his skin on his tummy and round by his tail has changed colour to black. He is quite happy, loving, eating and drinking normally and pooing normal. Has anyone had a dog with any of these problems and if so, what was done. many thanks

my old gsp had the odd dribble but not the fur colour change. Hers was just old age as she was 16/17 when it started.
If it is something that is going to be a regular occurrence you could get him a body band maybe?