Accuracy of the IDEXX SediVue Dx analyzer for quantifying RBC and WBC indices in the urine sediments of cats and dogs compared with manual microscopic evaluations.

BACKGROUND: The IDEXX SediVue Dx (SediVue) is an automated, in-clinic urine sediment analyzer for veterinary patients. The bias between the results from manual microscopy and the SediVue is currently unknown. OBJECTIVES: To assess the diagnostic accuracy of the SediVue, we aimed to determine the bias between the SediVue (index test) and manual microscopy (reference standard) for the quantification of RBCs and WBCs in urine. METHODS: Urine remnant samples were collected from cats and dogs that contained RBCs (n = 462) and WBCs (n = 510). Retrospective analysis of results from urine sediment examinations using both manual microscopy (using a KOVA and DeciSlide system) and the SediVue (1.0.1.3) was performed. Bias was determined with Bland-Altman plots. SediVue-captured images from high-bias samples were reviewed, and biases were compared. RESULTS: The median bias for semi-quantitative RBC and WBC counts was determined for RBC and WBC counts. The cutoffs were RBC ≤ 5/HPF, 0.3; RBC 5.1-10/HPF, 10.1; RBC 10.1-20/HPF, 10.6; and RBC > 20/HPF, 28.93; WBC ≤ 5/HPF, 0.1; WBC 5.1-10/HPF, 2.2; WBC 10.1-20/HPF, 9.4; and WBC > 20/HPF, 26.6. High bias between the methods was identified in 98 samples (21.0%) with RBCs and 77 samples (15.7%) with WBCs. Reviewer-based enumeration of the SediVue-captured images decreased the percentage of samples with high bias to 17.3% for RBCs and to 11.4% for WBCs. CONCLUSIONS: Bias in the RBC and WBC counts between manual microscopy and the SediVue was unlikely to impact clinical interpretations in a majority of cases. Although reviewer enumeration of SediVue-captured images reduced observed bias, inherent differences between methodologies appeared to have a larger impact on the bias.

Use of Margarine for the Successful Removal of Polyisobutylene in an Anhinga (Anhinga anhinga) and Great Blue Heron (Ardea herodias).

Two great blue herons (Ardea herodias) and an anhinga (Anhinga anhinga) were presented to the Wildlife Center of Texas with extensive plumage soiling from polyisobutylene (PIB), a synthetic rubber polymer used in manufacturing. All animals were provided supportive care and sedated for evaluation for hematologic and plasma biochemical values; one of the great blue herons was critically ill, based on the diagnostic evaluations and died approximately 24 hours after admission. On postmortem examination, it was diagnosed with coelomic migration of Eustrongylides species resulting in verminous peritonitis that was likely the primary cause of its poor condition and death, rather than the PIB exposure. Standard decontamination efforts with commercial liquid dish soap were unsuccessful. Application of margarine was used to emulsify the PIB on the remaining 2 birds and was followed by standard wash protocols for successful removal. These animals were successfully released after decontamination. The use of margarine for decontamination of PIB is unreported and could prove useful in future decontamination events in birds and other wildlife when traditional methods to remove hydrocarbon compounds are unsuccessful.

Comparison of the performance of the IDEXX SediVue Dx® with manual microscopy for the detection of cells and 2 crystal types in canine and feline urine.

BACKGROUND: Microscopic evaluation of urine is inconsistently performed in veterinary clinics. The IDEXX SediVue Dx® Urine Sediment Analyzer (SediVue) recently was introduced for automated analysis of canine and feline urine and may facilitate performance of urinalyses in practice. OBJECTIVE: Compare the performance of the SediVue with manual microscopy for detecting clinically relevant numbers of cells and 2 crystal types. SAMPLES: Five-hundred thirty urine samples (82% canine, 18% feline). METHODS: For SediVue analysis (software versions [SW] 1.0.0.0 and 1.0.1.3), uncentrifuged urine was pipetted into a cartridge. Images were captured and processed using a convolutional neural network algorithm. For manual microscopy, urine was centrifuged to obtain sediment. To determine sensitivity and specificity of the SediVue compared with manual microscopy, thresholds were set at ≥5/high power field (hpf) for red blood cells (RBC) and white blood cells (WBC) and ≥1/hpf for squamous epithelial cells (sqEPI), non-squamous epithelial cells (nsEPI), struvite crystals (STR), and calcium oxalate dihydrate crystals (CaOx Di). RESULTS: The sensitivity of the SediVue (SW1.0.1.3) was 85%-90% for the detection of RBC, WBC, and STR; 75% for CaOx Di; 71% for nsEPI; and 33% for sqEPI. Specificity was 99% for sqEPI and CaOx Di; 87%-90% for RBC, WBC, and nsEPI; and 84% for STR. Compared to SW1.0.0.0, SW1.0.1.3 had increased sensitivity but decreased specificity. Performance was similar for canine versus feline and fresh versus stored urine samples. CONCLUSIONS AND CLINICAL IMPORTANCE: The SediVue exhibits good agreement with manual microscopy for the detection of most formed elements evaluated, but improvement is needed for epithelial cells.