Cobas 311

The CSF samples were submitted to the Auburn University, College of Veterinary Medicine clinical pathology laboratory for cytologic analysis within approximately 1 hour of collection, as previously recommended.
² (link) Samples were evaluated for color, transparency, total protein concentration (TPC), total nucleated cell count (TNCC), and red blood cell count (RBCC). The TNCC and RBCC were obtained using a manual hemocytometer (Hausser Scientific, Horsham, Pennsylvania, USA). Total protein concentration was determined using a biochemical analyzer (Cobas 311, Roche Diagnostics, Indianapolis, Indiana, USA). A board‐certified clinical pathologist performed cytologic evaluation of the samples and was blinded to the study details and sampling technique used.

Calprotectin was measured in all fecal extracts using the fCal turbo assay on a Roche Cobas 311 chemistry analyzer as previously validated for feline specimens [43 (link)]. Briefly, fecal extracts were incubated with proprietary reaction buffer and mixed with polystyrene nanoparticles that had been pre-coated with polyclonal anti-human calprotectin antibodies. Agglutination by binding of fCal increases sample turbidity and was measured at 546 nm and 800 nm, and the fCal concentration was determined by interpolation from the calibration curve [42 ,43 (link)]. The assay has a working range from 3–2000 μg/g for feline samples, and samples with a fCal concentration >2000 μg/g were re-assayed in a 1:1000 dilution.

Fasting plasma samples were obtained from study participants after an overnight fasting on first day of hospitalization. Serum cholesterol, triglycerides (TG), HDL-C, and low-density lipoprotein cholesterol (LDL-C) were measured by enzymatic colorimetric method with commercially available kit (COBAS 311, Roche Diagnostics GmbH, Mannheim, Germany). Serum concentrations of glucose were determined enzymatically using the hexokinase method (Roche Diagnostics GmbH, Mannheim, Germany). The particle-enhanced immunoturbidimetric method with Behring BN-100 Nephelometer (Behring Diagnostics, Frankfurt, Germany) was used to measure C-reactive protein (CRP). Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT), creatinine, and uric acid were assessed by using a commercial biochemistry analyzer (Roche p800 Modular, Roche Diagnostics, Indianapolis, IN, USA).