A multicenter retrospective study assessing progression of biliary sludge in dogs using ultrasonography.

BACKGROUND: Biliary sludge (BS) frequently is identified on ultrasonographic examination and is described as incidental. It is hypothesized that biliary stasis and hypersecretion play a role in both BS and gallbladder mucocele (GBM) formation. Recent studies have documented similarities in composition of BS and GBM, and there are several examples of progression from BS to GBM in the veterinary literature. OBJECTIVES: To assess the relationship between the presence of BS and later development of GBM in dogs, over time periods >12 months. ANIMALS: A total of 154 dogs with BS and ultrasonographic follow-up >12 months. METHODS: Medical records were retrospectively collected from 9 UK-based referral centers for all available time points. A semiobjective scoring system was used to track volume of BS within the gall bladder (GB) over time. RESULTS: Twenty dogs developed GBM during the study period. Shetland Sheepdogs (odds ratio [OR], 40.99; 95% confidence interval [CI], 3.61-465.95; P = .003) and Border Terriers (OR, 11.66; 95% CI, 3.28-46.63; P < .001) were independent risk factors for the development of GBM. Non-gravity-dependent BS (NDBS) was noted to form before GBM development in 9/20 dogs, and breeds at-risk for GBM were more likely to have NDBS. Odds for the development of GBM increased with BS score. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with NDBS may be at risk for the development of GBM and a stratified BS scoring system could allow for semiobjective monitoring over time, particularly in at-risk breeds.

Validation and determination of a reference interval for canine HbA1c using an immunoturbidimetric assay.

BACKGROUND: Hemoglobin A1c (HbA1c) provides a reliable measure of glycemic control over 2-3 months in human diabetes mellitus. In dogs, presence of HbA1c has been demonstrated, but there are no validated commercial assays. OBJECTIVE: The purpose of the study was to validate a commercially available automated immunoturbidimetric assay for canine HbA1c and determine an RI in a hospital population. METHODS: The specificity of the assay was assessed by inducing glycosylation in vitro using isolated canine hemoglobin, repeatability by measuring canine samples 5 times in succession, long term inter-assay imprecision by measuring supplied control materials, stability using samples stored at 4°C over 5 days and -20°C over 8 weeks, linearity by mixing samples of known HbA1c in differing proportions, and the effect of anticoagulants with paired samples. An RI was determined using EDTA-anticoagulated blood samples from 60 nondiabetic hospitalized animals of various ages and breeds. Hemoglobin A1c was also measured in 10 diabetic dogs. RESULTS: The concentration of HbA1c increased proportionally with glucose concentration in vitro. For repeat measurements, the CV was 4.08% (range 1.16-6.10%). Samples were stable for 5 days at 4°C. The assay was linear within the assessed range. Heparin- and EDTA-anticoagulated blood provided comparable results. The RI for HbA1c was 9-18.5 mmol/mol. There was no apparent effect of age or breed on HbA1c. In diabetic dogs, HbA1c ranged from 14 to 48 mmol/mol. CONCLUSIONS: The assay provides a reliable method for canine HbA1c measurement with good analytic performance.