Comparison of gel column agglutination with monoclonal antibodies and card agglutination methods for assessing the feline AB group system and a frequency study of feline blood types in northern Italy.

Background: A new commercial gel column agglutination system is reported to have high sensitivity in detecting cats with blood type AB.

Objectives: The aims of this study were to compare gel column agglutination and card agglutination methods for feline blood-typing and to determine the frequency distribution of feline blood types in northern Italy.

Methods: Blood-typing was performed on 120 cats using both a commercial gel column containing monoclonal antibodies (ID Gel-Test Micro Typing System) and a card agglutination method (RapidVet-H Feline). Results were confirmed with back-typing. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for the 2 methods. A second group of 140 Domestic Shorthair (DSH) cats was blood-typed using the gel column technique to determine the frequency distribution of feline blood types in northern Italy.

Results: The card agglutination method demonstrated poor sensitivity in identification of type-AB cats (61%) and was only 95% specific when identifying type-B cats. The gel column agglutination technique demonstrated 100% sensitivity and specificity for typing all 3 blood types (A, B, and AB). The frequency distribution study of 140 cats demonstrated that 127 (90.7%) cats were type A, 10 (7.1%) were type B, and 3 (2.1%) were type AB.

Conclusion: When blood-typing cats of breeds with a relatively high frequency of blood types B and AB, methods that use monoclonal antibodies for detection of blood types B and AB are recommended. Alternatively, blood type can be confirmed by more sensitive supplemental testing, such as back-typing. The high frequency of blood type A in DSH cats in northern Italy was comparable to previously reported frequencies in Italy and world-wide.