|Fluid Specimens (ascitic, pleural effusions)|
|Tissue biopsies/aspirates (of affected organ or lymph node)|
|EDTA-blood as is, purple-top tube|
Fecal Specimens/swabs (for exclusion of acute enteric feline coronavirus infection)
This PCR test detects mRNA of the M gene of all known feline coronavirus strains in any sample; however, for diagnosis of FIP, only the detection of mRNA outside of the intestinal tract is indicative since active replication of the virus in circulating mononuclear cells is typical for FIP. In contrast, non-FIP feline coronavirus strains replicate in the intestinal tract, but not in blood mononuclear cells.