Response to letter regarding "ACVIM consensus statement on pancreatitis in cats".

Dear Editors,

Thank you for giving us the opportunity to respond to Dr Törner's and Dr Aupperle‐Lellbach's letter. We would like to start by apologizing for not citing 1 of their papers in the consensus statement. This certainly was not done with any ill intent. However, the consensus statement included 209 references and the panel had to choose which references to include. The consensus statement was limited to 10 000 words for the final document, which we were only able to reach by repeatedly cutting material. Also, in contrast to what is stated by Dr Törner and Dr Aupperle‐Lellbach, the focus of this consensus statement is not, and was not intended to be, the diagnosis of pancreatitis in cats, but rather a holistic summary of the disease. Thus, many details in all of the sections had to be omitted.

We would like to explain our decision not to include the reference by Törner et al. This study investigated the association of feline pancreas‐specific lipase (fPLI) concentrations with underlying histopathology, and we felt that it underscored the existing literature with respect to pancreatitis in cats, and did not add new information. In addition, the study by Törner et al focused on fPLI concentrations in cats with neoplastic diseases of the pancreas, which are rare in cats and were not the focus of our statement. While we did acknowledge in the cytology section that pancreatic adenocarcinoma can be difficult to differentiate from primary pancreatitis, as neoplasia is often associated with an inflammatory reaction, we did not repeat the same statement for serum diagnostics.

The panel would like to apologize for citing reference 100 for the statement about the analytical validation failure of the fPLI assay by Laboklin. As correctly stated by Dr Törner and Dr Aupperle‐Lellbach, the only reference that reported on the failure of analytical validation of the fPLI assay by Laboklin was reference 103, which as the authors of the letter correctly point out, was written in German with an abstract in English. However, we do not feel that this fact is relevant as 3 panel members were able to read the paper in detail in the original German and the tables of this paper together with the abstract would have provided detailed information about this study for all panel members. To the panel's knowledge, there has been no publication that has reported on adjustments to this assay or a detailed analytical validation. The reference by Törner et al does provide some summary data on the analytical validation of this assay, but allows no determination of the modifications to the assay or the details of the analytical validation of the assay, as no raw data were provided.

The statement concerning discordance of the 1,2‐o‐dilauryl‐rac‐glycero‐3‐glutaric acid‐(6'‐methylresorufin) ester (DGGR) assay with serum fPLI was simply based on Cohen's kappa coefficient of 0.7 reported in the study by Oppliger et al and was appropriately cited. The panel felt that no further discussion was needed as a value of 0.7 for 2 assays that supposedly measure the same analyte demonstrates discordance.

The panel agrees with the authors of the letter about the limited gold standard nature of histopathology (ie, when changes are identified on histopathology a diagnosis of pancreatic inflammation can be made; however, changes may be localized and thus the diagnosis may be missed), which is what was stated in the consensus statement. However, as is the case in humans and in dogs, a histopathologic diagnosis of acute pancreatitis in cats is usually limited to patients that die of the disease or, as may be the case in dogs and cats, are euthanized, as the collection of a biopsy is often not in the best interest of the patient.

Finally, the panel also agrees with the authors of the letter that no single diagnostic test should be blindly trusted when arriving at a diagnosis of pancreatitis, which is why the panel concluded the consensus statement by stating that: “Pancreatitis is amenable to antemortem diagnosis by integrating all clinical and diagnostic information available.”

In summary, the letter by Dr Törner and Dr Aupperle‐Lellbach highlights many of the statements that were made in our consensus statement. However, we do respectfully disagree that the consensus statement did not fulfill the requirements for a consensus statement. Eight recognized experts from 3 continents, representing 4 disciplines, both from private practice and from academia met for more than 40 working hours (in person and through Zoom meetings) and repeatedly discussed every sentence in this statement. Potential conflicts of interest were appropriately disclosed, both before accepting participation on the panel and during presentation and publication. Is the final product perfect? Certainly not. Will it lead to further discussion? Obviously and thankfully so!

Thank you!