Not all lumps are bad news.
Merry came in today with a lump on her back.
Very quickly we were able to ascertain from a biopsy in house that it was not a tumor like she has had before but an infection.
The squiggly cells in the photo (from our microscope) are neutrophils that are attracted to body sites like the skin when there is a bacterial disease. Under higher power we could see bacteria most likely to be streptococcal or staphylococcal bacteria. This is called a superficial pyoderma or colloquially a hot spot.
Treatment: medicated shampoo Mediderm and antibiotics.

