Boxer dog

Hello Vets. I have an almost 4 year old boxer named Pearl. Health history: she suffers from severe environmental allergies, but they are well controlled with immunotherapy & medication. She has had some issues with anal glands spontaneously expressing (while sleeping) since she was a puppy, it has improved with high fiber dog food. Last December, she had an Acanthomatous Ameloblastoma (CAA) on her gum, it was caught early & removed. Last week, I noticed a white bump, about the size of a pin head on her rectum when she was pooping. It’s on the skin on the inside of her rectum, so you can only see it at that time. I took her to the vet yesterday, and he did feel the bump & said it was hard. She was put on 10 days of clindamycin in case it’s an anal gland issue. If it’s still there in 10 days, we go back and will schedule to have it removed. I really like my vet and trust him, but I thought in a case like this, it might be helpful to get more than one opinion, as it seems like it might be a little bit of an unusual situation. Any insight would be greatly appreciated, thank you for your time!

Hello!  I'm a little bit uncertain as to what this is but I can see where your vet is coming from - they are giving antibiotics and time, which may be enough to get rid of any pustules (ie superficial bacterial skin lumps) and so prevent an unnecessary biopsy.   Failing that and if the lump isn't reducing, they may decide to biopsy to be completely sure that it isn't something unpleasant.  I also wonder whether demodex might occasionally present like this - if the part that you are showing me is external? - and if I wasn't sure then I might be tempted to check with a friendly pathologist (we vets do this all the time in case there was something else that they reccommended).  Wishing you the best of luck and please do let me know how Pearl gets on!