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My dog has a painful white back lump and bloody diarrhea. What's wrong?

Updated On September 23rd, 2025

Pet's info: Dog | Border Collie | Male | unneutered | 2 years and 2 months old | 45 lbs

Hard lump in his back. White. Looks like little white dots around his hair follicles. Doesn't like when I touch it. Diarrhea today with blood.

1 Answer

Most Helpful Answer

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Answered By Destini R. Holloway, DVM

Veterinarian

Published on February 20th, 2019

Poor guy. The hard lump is hard to say what it is without a photo. It could be a condition called folliculitis or even a pustule (infected pocket). However, with bloody diarrhea, I would highly recommend taking Merlo in to your vet to get him examined and stool tested. Lots of things can cause loose bloody stool including: parvovirus infection, pancreatitis (usually causes vomiting as well and decreased appetite), stress colitis, etc. Once Merlo is examined, the vet will likely put him on a short course of antibiotics and probiotics at the very least for the loose stool. The hard lump will have to be examined first to determine what, if anything, needs to be done for this as well. I hope that your furry friend Merlo gets these issues resolved soon! Best of luck and take care.

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