Petco Text Logo
Petco Pet Logo

My dog has a lump with yellow fluid. Is it spinal fluid or a cyst?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Large (61lb +) | Male | neutered | 10 years and 1 month old | 64 lbs

My diabetic dog is 10-yrs old and just presented with a fluid filled lump a couple of months ago. I finally stuck it to see what was inside and came back with a clear fluid with a slight yellow hue. I have two full 30 unit syringes that were filled at two different times, about two weeks apart cuz my dog's lump filled back up after being drained once. So, the darker syringe is older and has been sitting for a couple of weeks. Gross, ik. Is this spinal fluid or something else?

This question includes photos that may contain sensitive content. Click to view.

View more to consider that the photos may include sensitive content.

1 Answer

Most Helpful Answer

Image profile

Answered By Destini R. Holloway, DVM

Veterinarian

Published on December 5th, 2018

The fact that this has been there for so long, and the straw color to the fluid suggests that this is likely just a cyst. They tend to fill back up after being drained, but are usually benign. You wouldn't be able to drain spinal fluid from your pets skin. You can have the cyst surgically removed to resolve this for good or keep having it drained by your vet, since they can use sterile methods to prevent it from getting infected. If the discharge is ever reddish brown in color, then it is likely an abscess and requires antibiotics to resolve. I hope that Cocoa continues to do well. Best wishes and take care.

Vote icon

1Pet Parents found this answer helpful

image
Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Sponsored