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Immune thrombocytopenia (ITP) is the most common acquired primary hemostatic disorder in dogs. Immune thrombocytopenia less commonly affects cats but is an important cause of mortality and treatment‐associated morbidity in both species. Immune thrombocytopenia remains a diagnosis of exclusion for which diagnostic guidelines are lacking. Primary, or non‐associative, ITP refers to autoimmune platelet destruction. Secondary, or associative, ITP arises in response to an underlying disease trigger. However, evidence for which comorbidities serve as ITP triggers has not been systematically evaluated. To identify key diagnostic steps for ITP and important comorbidities associated with secondary ITP, we developed 12 Population Evaluation/Exposure Comparison Outcome (PECO) format questions. These questions were addressed by evidence evaluators utilizing a literature pool of 287 articles identified by the panelists using a structured search strategy. Evidence evaluators, using panel‐designed templates and data extraction tools, summarized evidence and created guideline recommendations that then were integrated by diagnosis and comorbidity domain chairs. The revised PECO responses underwent a Delphi survey process to reach consensus on final guidelines. A combination of panel expertise and PECO responses were employed to develop algorithms for diagnosis of ITP in dogs and cats, which also underwent 4 iterations of Delphi review. Comorbidity evidence evaluators employed an integrated measure of evidence (IME) tool to determine evidence quality for each comorbidity; IME values combined with evidence summaries for each comorbidity were integrated to develop ITP screening recommendations, which also were subjected to Delphi review. Commentary was solicited from multiple relevant professional organizations before finalizing the consensus. The final consensus statement provides clinical guidelines for the diagnosis of, and underlying disease screening for, ITP in dogs and cats. The systematic consensus process identified numerous knowledge gaps that should guide future studies. This statement is a companion manuscript to the ACVIM Consensus Statement on the Treatment of Immune Thrombocytopenia. [ABSTRACT FROM AUTHOR]

Background: In dogs, 6 single‐nucleotide polymorphisms (SNPs) have been described in the glucocorticoid receptor gene NR3C1a, 2 of which were nonsynonymous SNPs in exons 2 and 8. The clinical importance of these SNPs is unknown. Objectives: To investigate whether SNPs in NR3C1a are associated with clinical outcome in Cocker Spaniels with primary immune thrombocytopenia (pITP). Animals: Twenty‐four Cocker Spaniels with pITP presented to a referral center. Dogs were classified as slow (n = 11) or fast responders (n = 12) based on time required after initiating glucocorticoid treatment to achieve a platelet count >70 000/μL. Methods: Deoxyribonucleic acid was extracted from stored blood samples before amplification by PCR and sequencing of exons 2 and 8 of NR3C1a. Associations between genotype and clinical response variables were investigated. Results: Neither previously identified nonsynonymous SNPs were identified. The synonymous SNP NR3C1a:c.798C>T in exon 2 was found at an increased prevalence compared to a previous report. No difference was found in prevalence of any genotype at NR3C1a:c.798C>T between fast and slow responders (P =.70). Conclusions and Clinical Importance: None of the previously reported nonsynonymous SNPs in exons 2 and 8 of the NR3C1a gene were detected in our cohort of Cocker Spaniels with pITP. The synonymous SNP NR3C1a:c.798C>T in exon 2 was reported at a higher frequency than previously, but was not associated with outcome measures that estimated responsiveness to glucocorticoids. [ABSTRACT FROM AUTHOR]

Objectives: Prednisolone is a commonly used drug in cats and potential adverse effects include hyperglycaemia and diabetes mellitus. The aims of this study were to evaluate the frequency and investigate potential predisposing risk factors for the development of prednisolone-induced diabetes mellitus (PIDM) in cats. Methods: The electronic records of a tertiary referral centre were searched for cats receiving prednisolone at a starting dose of ⩾1.9 mg/kg/day, for >3 weeks and with follow-up data available for >3 months between January 2007 and July 2019. One hundred and forty-three cats were included in the study. Results: Of the 143 cats, 14 cats (9.7%) were diagnosed with PIDM. Twelve out of 14 cats (85.7%) developed diabetes within 3 months of the initiation of therapy. Conclusions and relevance: Cats requiring high-dose prednisolone therapy should be closely monitored over the first 3 months of therapy for the development of PIDM. [ABSTRACT FROM AUTHOR]

Background: Breed predispositions, survival, and prognostic factors have not been evaluated in dogs with nonregenerative immune‐mediated anemia (nrIMA). Hypothesis/Objectives: To describe clinicopathologic variables, evaluate their associations with survival, and determine breed predispositions for dogs with nrIMA. Animals Fifty‐nine client‐owned dogs with nrIMA. Methods: Referral hospital records were reviewed retrospectively for dogs with primary nrIMA (PCV ≤30%, corrected reticulocyte percentage (CR%) ≤1.0, bone marrow sampling with evidence of immune‐mediated destruction, and underlying causes excluded). Breed predispositions were evaluated by calculation of odds ratios in a case control study; prognostic factors by logistic regression in a cohort study. Results: Fifty‐nine dogs with nrIMA had a median PCV of 12% (interquartile range [IQR]: 10%‐17%) and CR% 0.1 (0%‐0.2%). At least ≥1 ACVIM IMHA diagnostic criteria were met by 35 dogs (59%). Whippets, Lurchers, and miniature Dachshunds were predisposed to nrIMA. Median survival time was 277 days (IQR: 37‐1925), with 3‐ and 12‐month survival rates 61% and 43%, respectively. Erythroid regeneration and remission were achieved by 88% and 62% of dogs, respectively. Corrected reticulocyte percentage >0.2 was associated with improved survival. Conclusion and Clinical Importance: Although there is overlap of clinical features between dogs with IMHA and nrIMA, the prognosis for those with nrIMA depends predominantly on the severity of reticulocytopenia. [ABSTRACT FROM AUTHOR]

Imerslund-Gräsbeck syndrome (IGS) or selective cobalamin malabsorption has been described in humans and dogs. IGS occurs in Border Collies and is inherited as a monogenic autosomal recessive trait in this breed. Using 7 IGS cases and 7 non-affected controls we mapped the causative mutation by genome-wide association and homozygosity mapping to a 3.53 Mb interval on chromosome 2. We re-sequenced the genome of one affected dog at ∼10× coverage and detected 17 non-synonymous variants in the critical interval. Two of these non-synonymous variants were in the cubilin gene (CUBN), which is known to play an essential role in cobalamin uptake from the ileum. We tested these two CUBN variants for association with IGS in larger cohorts of dogs and found that only one of them was perfectly associated with the phenotype. This variant, a single base pair deletion (c.8392delC), is predicted to cause a frameshift and premature stop codon in the CUBN gene. The resulting mutant open reading frame is 821 codons shorter than the wildtype open reading frame (p.Q2798Rfs*3). Interestingly, we observed an additional nonsense mutation in the MRC1 gene encoding the mannose receptor, C type 1, which was in perfect linkage disequilibrium with the CUBN frameshift mutation. Based on our genetic data and the known role of CUBN for cobalamin uptake we conclude that the identified CUBN frameshift mutation is most likely causative for IGS in Border Collies. [ABSTRACT FROM AUTHOR]