This decreases surface area, increases osmotic fragility, and increases the likelihood that these cells will be captured and destroyed by the spleen. The attachment of M. haemofelis to red blood cell membranes is often associated with positive Coombs test results, meaning IgG antibodies have become bound to red blood cells, marking them for destruction. For the most part, the anemia seen in M. haemofelis infection is a result of extravascular erythrophagocytosis by macrophages in the spleen, liver, lungs, and bone marrow.[1]