The MSU VDL now offers a flow cytometric assay to detect IgG on canine RBCs to aid in the diagnosis of canine IMHA (test code 10642). Advantages of the flow cytometric assay over the Coombs' test include:

  • a lower detection limit for pathologic increases in RBC-IgG, and therefore increased diagnostic sensitivity for IMHA
  • a smaller sample volume requirement (0.5 mL)
  • the ability to test samples with RBC clumping/agglutination

Although this flow cytometric test detects only IgG, it is rare for dogs with IMHA to test positive for IgM, C3, and/or IgA without concurrent increases in IgG; therefore, the flow cytometric assay is expected to detect increased RBC IgG in the vast majority of dogs with IMHA.