Validation of a mobile clinical pathology laboratory for canine hematology and biochemistry

Abstract

Background: In clinical diagnosis and research, it is often essential to carry out laboratory tests that provide reliable results rapidly. However, in some circumstances, these tests are not available at the patient's location, leading to a delay before analysis that increases turnaround time and can cause pre-analytical errors. To this end, a new mobile laboratory van containing one hematology and one biochemistry benchtop analyzers was developed, and a validation study was performed under field conditions (i.e., after trips of varying distances) with canine specimens and quality control materials.

Results: Linearity was considered acceptable for all variables. Coefficient of variation was < 5% for biochemical variables and most hematological ones (0.0-8.11%) and imprecision was in line with the recommendations for all variables except for neutrophil count in the short-term imprecision. Observed total error for albumin with the quality control material was higher than allowable total error, secondary to a high bias. The comparison with the same model of analyzer showed significant bias for nearly all variables but observed total error remained lower than acceptable total error for all variables except for lymphocyte and reticulocyte counts.

Conclusion: Both analyzers exhibited acceptable performance in the mobile laboratory operating conditions, making them suitable for future use in the field.

Keywords: Benchtop analyzer; Biochemistry; Canine; Hematology; Laboratory van; Mobile laboratory; On-field; POCA; Validation study.

Fig. 1

Exterior (A) and interior (B) of the mobile laboratory van. The van is a fully operational laboratory equipped with many of the instruments and machines used in a conventional small-scale laboratory. These include a centrifuge, a refrigerator (+ 4 °C), two freezers (-20 °C and − 80 °C), a microbiological safety cabinet, a light microscope, an rapid stain kit, a tube agitator (Blood Tube Rocker 8-Tube, IDEXX Laboratories), one hematology analyzer (ProCyte Dx, IDEXX Laboratories), one biochemistry analyzer (Catalyst One, IDEXX Laboratories) both connected to the IDEXX VetLab Station (IVLS), one blood gas analyzer (VetStat, IDEXX Laboratories) and all the equipment needed for blood sampling including needles, syringes and blood collection tubes

Fig. 2

Passing-Bablok and Bland-Altman plots for selected hematological variables. On the Passing-Bablok plots (left), the thin gray line is identity line (y = x); the red line is the regression curve. On the Bland-Altman plots (right), the blue lines are the regression curve (solid line) with 95% CI (dotted lines) and 95%LoA (dashed lines).Abbreviations: CI, confidence interval; clin, in-clinic analyzer; HCT, hematocrit; HGB, hemoglobin concentration; LoA, limit of agreement; MCV, mean corpuscular volume; PLT platelet count; RBC, red blood cell count; RET, reticulocyte count

Fig. 3

Passing-Bablok and Bland-Altman plots for biochemical variables. On the Passing-Bablok plots (left), the thin gray line is identity line (y = x); the red line is the regression curve. On Bland-Altman plots (right), the blue lines are the regression curve (solid line) with 95% CI (dotted lines) and 95%LoA (dashed lines).Abbreviations: ALP, alkaline phosphatase; ALT, alanine amino transferase; Ca, calcium; CI, confidence interval; Clin, in-clinic; LoA, limit of agreement