Dear Editors,We read with interest the paper by Estruch et al "Utility of the combined use of 3 serologic markers in the diagnosis and monitoring of chronic enteropathies in dogs," 1 the results section of the abstract of which would suggest that an assay based on combined measurements of OmpC (ACA), canine calprotectin (ACNA), and gliadinderived peptide (AGA) is useful to differentiate chronic enteropathy/ inflammatory bowel disease (CE/IBD) and non-IBD gastrointestinal disorders. 1 However, in the materials and methods section, the differentiation of dogs with primary gastrointestinal disease from those with some forms of secondary gastrointestinal disease is described,

Intestinal lymphangiectasia was first described in the dog over 50 years ago. Despite this, canine IL remains poorly understood and challenging to manage. Intestinal lymphangiectasia is characterized by variable intestinal lymphatic dilation, lymphatic obstruction, and/or lymphangitis, and is a common cause of protein-losing enteropathy in the dog. Breed predispositions are suggestive of a genetic cause, but IL can also occur as a secondary process. Similarly, both primary and secondary IL have been described in humans. Intestinal lymphangiectasia is definitively diagnosed via intestinal histopathology, but other diagnostic results can be suggestive of IL. Advanced imaging techniques are frequently utilized to aid in the diagnosis of IL in humans but have not been thoroughly investigated in the dog. Management strategies differ between humans and dogs. Dietary modification is the mainstay of therapy in humans with additional pharmacological therapies occasionally employed, and immunosuppressives are rarely used due to the lack of a recognized immune pathogenesis. In contrast, corticosteroid and immunosuppressive therapies are more commonly utilized in canine IL. This review aims toward a better understanding of canine IL with an emphasis on recent discoveries, comparative aspects, and necessary future investigations.

Background The relationship between the development of SHPT and ionized magnesium (iMg) concentrations in blood of dogs with chronic gastrointestinal (GI) disease and abnormally low 25(OH)D is undefined. Objectives Evaluate relationships between ionized magnesium (iMg), PTH, ionized calcium (iCa), and 25(OH)D in dogs with chronic enteropathy (CE) with or without protein‐losing enteropathy (PLE) and abnormal 25(OH)D. Determine whether dogs with CE or PLE, decreased 25(OH)D and SHPT have differences in iMg, iCa, or 25(OH)D when compared to dogs that do not have SHPT. Animals Fifty dogs with CE +/− PLE and abnormally low serum 25(OH)D. Methods Retrospective search of submissions database at a veterinary diagnostic laboratory for vitamin D profiles submitted in years 2017 to 2020. Cases were excluded if supplemented with Ca, Mg, or vitamin D. Spearman correlation was performed to evaluate relationships between iMg, PTH, 25(OH)D, and iCa. Ionized Mg, iCa, and 25(OH)D concentrations were compared between dogs with SHPT and those with normal PTH concentrations. Results Concentrations of iMg were weakly negatively correlated with PTH (rho, −.31; P = .03), and weakly positively correlated with serum 25(OH)D (rho, .34, P = .02) and iCa (rho, .42, P = .003). Ionized magnesium concentrations were lower in dogs with abnormally low 25(OH)D and SHPT compared to dogs with abnormally low 25(OH)D and normal parathyroid hormone concentrations (P = .01). Conclusions and Clinical Importance Hypomagnesemia might contribute to alterations in iCa and parathyroid hormone in dogs with CE +/− PLE and abnormally low 25(OH)D.

Background A panel of IgA‐based serologic assays might aid in the diagnosis of chronic enteropathy (CE) in dogs, a syndrome encompassing conditions such as food‐responsive enteropathy, immunosuppressant‐responsive enteropathy, and inflammatory bowel disease (also referred to as chronic inflammatory enteropathy). However, it is unclear whether these biomarkers discriminate between CE and other types of primary intestinal disorders. Objectives To evaluate a diagnostic panel that measures serum concentrations of IgA directed against OmpC (ACA), canine calprotectin (ACNA), and gliadin‐derived peptides (AGA) in dogs with well‐characterized intestinal diseases. Animals Fifty‐five dogs with primary intestinal disease. Methods Serum ACA, ACNA, and AGA concentrations were measured in 30 dogs with CE and 25 dogs with other intestinal diseases (non‐CE population), including histoplasmosis, parasitism, E . coli ‐associated granulomatous colitis, and lymphoma. Serum IgA concentrations were compared among populations, and sensitivities and specificities were calculated using laboratory‐provided cut‐points. Results Twenty‐six of 30 (87%) CE dogs and 21 of 25 (84%) non‐CE dogs had abnormal concentrations (intermediate or high) of at least 2 markers; these proportions were not significantly different ( P = .99). A serum ACA concentration ≥15 EU/mL was 86.7% (95% confidence interval [CI], 69.3%‐96.2%) sensitive and 24.0% (95% CI, 9.4%‐45.1%) specific for CE diagnosis. High AGA concentrations were observed in 16 of 25 (64%) non‐CE dogs. Conclusions and Clinical Importance The evaluated serologic markers were poorly specific for CE diagnosis, which raises concerns that their use in clinical practice might lead to misdiagnoses and delayed or even detrimental treatments in dogs with non‐CE intestinal diseases.

Objectives: To assess platelet function via the Multiplate analyser in dogs undergoing laparoscopic liver biopsy for diagnosis of chronic hepatopathy.Materials and MethOds: Twenty-seven client-owned dogs were prospectively enrolled. Before laparoscopic liver biopsy, whole blood impedance platelet aggregometry via the Multiplate analyser was performed. Buccal mucosal bleeding time was performed in 23 of 27 dogs. Tissue factor-activated thromboelastography was also performed, in addition to plasma-based coagulation testing. Descriptive statistics were calculated and the prevalence of platelet function abnormalities and results of other biochemical and coagulation testing were reported.results: Seventeen (63%) of 27 dogs had evidence of decreased platelet function as assessed by aggregometry, with all 17 dogs having decreased responsiveness to adenosine diphosphate, and 11 of 17 dogs demonstrating decreased responsiveness to arachidonic acid. Based on maximum amplitude, most dogs were classified as normocoagulable on thromboelastography (15/25; 60%). Other frequent coagulation abnormalities included increased D-dimers (20/27;74%), thrombocytopenia (11/27; 41%), hypofibrinogenemia (4/27; 15%), and decreased antithrombin (4/27; 15%). clinical significance: Decreased platelet function as assessed by whole blood impedance aggregometry was common in dogs with chronic liver disease. Further study is necessary to determine whether this finding is repeatable or indicative of increased bleeding risk.