The causative bacterial agent of cat scratch disease has been identified as Bartonella henselae. In the past, complicated silver stains and/or PCR were used to identify and confirm this agent. This monoclonal Cat Scratch antibody aids to identify Bartonella henselae in formalin-fixed, paraffin-embedded (FFPE) tissues. Cross-reactivity tests were performed on 12 Bartonella henselae strains, 11 Bartonella quintana strains, 2 Bartonella bacilliformis strains and 1 B. elizabethae, 1 B. grahamii, 1 B. taylorii, 1 B. doshiae and 1 B. vinsonii strains. Reactivity was only obtained with Cat Scratch antibody (Bartonella henselae).