Sore between ears

Hello, our French Bull dog, has developed something in between his ears.  Originally it looked like something sticky was stuck in his fur so I used my finger nail again his fur to scrape it out. Nothing sticky came out but his fur did. It just fell out. We then noticed it was spreading and this morning it looks more like this!   Very hard to see, but it's almost got a yellow sticky discharge which is actually in the fur around it to. It seems to be getting worse. We have been washing it with warm salt water. We will be taking him to a vet on Monday, but does anyone know what it could be? I doubt it is this, but he caught his dew claw in a blanket 2 weeks ago, and went to the get it pulled off at the vets, and had an injection in a similar area between his ears/neck Possible infection from that?   Thanks Joe

Hello!   Between the ears would be an odd place to give an injection; usually they are given in the scruff further back.  This looks closer to the ear. Injection infections shouldn't happen as the needle used is usually sterile these days, although they can occur rarely eg if bugs are carried from the fur on the way in.  I can't remember seeing one but can't completely rule it out as this is not my patient (and certainly can't rule it in). I wonder if this is something I call 'wet dermatitis,' an infection that spreads superficially across the skin oozing pus.  It is often hard to know what started it; scratching the area over the ear canal due to possible ear inflammation (bugs in dogs nails then enter the skin) is a popular assumption in this location. If that is what's going on, it can spread outwards very rapidly so is best seen sooner rather than later.   Treatment is often topical these days, with genuine antibiotic and antifungal shampoos (not the same as antibacterial shampoos from the pet shop), although some vets do give oral meds. Other possibilities might include chemical splashes or fight wounds / cat scratch wound etc. Your emergency vet will let you know if you call them how soon they want to see this. Bathing in salt water sounds like a good idea as long as chemicals are definitely not involved. Best of luck