Validation of a Human Immunoturbidimetric Assay to Measure Canine Albumin in Urine and Cerebrospinal Fluid

Abstract

The aim of this study was to validate an automated immunoturbidimetric assay used to quantify human albumin in urine and to accurately measure canine albumin concentrations in both urine and cerebrospinal fluid. The partial homology existing between human and canine albumin limited the accuracy of the human assays in measuring canine albumin without method modifications. Thus, the assay was modified by calibrating the analyzer with calibrators made in the laboratory containing known concentrations of canine albumin. To prepare the set of calibrators, the albumin concentration of pooled sera of healthy dogs was assessed in 5 replicates using the BromocresolGreen assay. Pooled samples were aliquoted and serially diluted to obtain the expected concentrations of albumin (0.5, 1, 5, 13, and 30 mg/dl) for establishing the canine calibration curve. Thereafter, the performance was assessed by analyzing canine urine and CSF The modified assay accurately quantified canine albumin in both specimens, as indicated by the following. Intra- and interassay variability was 0.92% and 2.74%, respectively; recovery was 99.66% and 99.07% in urine and 105.02% in CSF No interference was detected when hemolysate and glucose were added to urine. The test was linear within the verified range (0-225 mg/dl). These results demonstrate that the modified human albumin immunoturbidimetric assay can be a useful tool in the veterinary diagnostic laboratory. It is accurate and tends itself to automatization on chemistry analyzers.

Ratio of urinary protein to creatinine and albumin to creatinine in dogs with diabetes mellitus and hyperadrenocorticism

“…Dogs were considered hypertensive whenever systemic blood pressure was found ≥160 mmHg. The urine was assayed for U:P/C and U:A/C (Gentilini et al 2005). The data between groups were compared using the Mann-Whitney U test.…”

Clinicopathologic Features and Outcome Predictors of Leptospira interrogans Australis Serogroup Infection in Dogs: A Retrospective Study of 20 Cases (2001–2004)

“…The urinary albumin concentration was determined by an automated immunoturbidimetric assay g designed for humans and validated for dogs in the VCD laboratory. 16 A UAC .0.05 was considered abnormal. 17 Proteinuria was qualitatively evaluated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) h on frozen samples.…”

Evaluation of the effect of oral omeprazole on canine cerebrospinal fluid production: A pilot study

“…A calibration of the human nephelometric assay (BNII system, Kit N AS ALB, Siemens Healthcare) was deemed necessary because the monoclonal antibody against human albumin used in the assay shared only a partial cross-reactivity with canine albumin (Gentilini et al, 2005;Murgier et al, 2009). A calibration curve was constructed by diluting a solution of purified canine albumin (Canine Albumin Protein ab119814, Abcam) to concentrations varying between 1.6 and 100 mg/dL using 0.9% saline.…”