We just dealt with the same thing for my two pugs ages 2 and 6. They developed the sores almost at the same time last summer and after a ton of research and trips to the vet we have gotten a pretty fair hold on the problem. First we tried all kinds of medication and antibiotics, but none of it seemed to work. The poor babies were miserable and they would even chew at their feet. Finally we took the younger one to the vet to get a biopsy. The vet agreed we didnt need to test both pugs because whatever we were dealing with was the same issue for both dogs. And we tested our younger one because we were told he could take the abuse a little easier. Anyway after testing we got the results back about a week later and they were cancer free which was expected. The vet put our dogs on a strict diet as we found out our food had some ingridients such as wheat,corn,soy that probably were not helping. We switched to blue buffalo. Expensive but worth it.
I think the real change has come mainly from the cleaing regimet we follow now also as directed by our vet. At first for a period of 2 weeks we washed their paws with a mixture of 4 Tb spoons white vinegar per gallon of purified water each morning and made sure to dry their feet very well to avoid breeding more infection. At the end of the first week the little pussy nobs between the toes began to collapse and the smell even went away. By two weeks they were all but gone and now after a month we are in the clear. Of course after the first 2 wks we slowed the treatment down to once every 2 days. Our vet said we would never be completely sure why our dogs developed this, but he was sure the food we had them on wasn’t sufficient and probably hurt their immune system which didnt help one bit. Also our dogs spend most of the day outside in the Summer and this can be bad as it promotes wet paws which can breed infections easier. Well at the end of the day all dogs and circumstances are different, but it sounded like you have the same prblem as we did so thought maybe I could help. – Sara and Bob