To Chris Perry: >We have a six year old female ferret who seems to have an enlarged spleen... >we are worried about not having the surgury if she needs it, and worried as >well about putting her through a life threatening surgury if not necessary >at all.... The vast majority of enlarged spleens are benign problems that do not threaten your ferret's health, however, about 5% overall can be due to tumors, the most common being lymphosarcoma. 95% of splenic enlargements are due to a massive proliferation of red and white blood cell precursors. This change is due to the presence of a chronic smouldering infection, the most common of which is gastric infection with a bacteria called Helicobacter mustelae (which almost every ferret has). Usually, this problem is worked up by examining the animal and seeing if other signs of a chronic infection are present - bloodwork, and occasionally, an aspirate of the spleen itself with a needle, which can be examined under the microscope. That often gives you at least a preliminary diagnosis of hematopoiesis vs. lymphosarcoma. I generally recommend splenic removal only if a) the animal has become lethargic due to the presence of the enlarged spleen, and b) an infection is not identified. Removal of the spleen in ferrets is a relatively simple operation, and they tolerate life without spleens better than any other type of animal.... Bruce Williams, DVM, DACVP Chief Pathologist, AccuPath Dept. of Veterinary Pathology [log in to unmask] Armed Forces Institute of Pathology [log in to unmask] [Posted in FML issue 1721]