Vista 1500

Technical specifications for the analytical equipment used in CSF analysis have been outlined in the methods section of the 2017 manuscript by McCudden et al3 (link):
CSF-TP was analysed on three different instruments over the course of the 20 years included in the study as follows: Roche Hitachi 917, 1 January 1996 to 30 September 2001; Beckman Lx20, 30 September 2001 to 1 April 2009 and Siemens Vista 1500, 1 April 2009 to 1 December 2016. The Roche method is based on a benzethonium chloride turbidimetric analysis, whereas the Beckman and Siemens methods use a pyrogallol red-molybdate complex, which is measured at 600 nm. In all cases, analyses were performed according to the manufacturer’s directions.
Other laboratory values were measured on different instruments across the two decades included in the study. Serum creatinine, TP and CSF glucose were measured on the platforms described above for the same time frames; creatinine was measured by the Jaffe method from 30 September 2001 to 13 April 2013 and by the enzymatic method thereafter. CSF WCC and RCC counts were determined using the Beckman Coulter between 1996 and 2009 and the Sysmex XE5000 from 2009 to 2016. All laboratory analyses were determined according to the manufacturer’s instructions throughout the study in a routine clinical laboratory in an academic medical centre (The Ottawa Hospital).

The laboratory tools used in our institution are as follows: 1) arterial blood gas analyzer (RAPIDLab 1265; Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA); 2) CBC (ADVIA2120i, Siemens Healthcare Diagnostics Inc.); and 3) chemical electrolyte analyzer (VISTA 1500; Siemens Healthcare Diagnostics Inc.). According to our machine, the normal range of the concentration of serum chloride is 98 to 107 mmol/L. Above 107 mmol/L will be defined as hyperchloremia.

Serum total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C), triglycerides (TGs), glucose (Glu), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels were measured by the enzymatic procedures run on Siemens Vista 1500 instrumentation (Clinical laboratory of Richmond VA Medical Center). Serum insulin was measured by the sensitive ELISA sandwich assay method using Crystal Chem Ultra-sensitive mouse insulin ELISA kit (Elk Grove Village, IL, catalogue # 90080) according to manufacturer’s instruction. IR was assessed by using homeostasis model assessment of insulin resistance (HOMA-IR) score calculated as [glucose (mg/dl) x insulin (ng/ml) × 26 / 405]. Liver TC was measured by the enzymatic assay using the Cholesterol E Kit (FUJIFILM Wako Chemicals, catalogue # 999-02601). Infinity Triglycerides Kit (Thermo Fisher Scientific, catalogue # 22421) was used for liver TG measurement. Abcam free fatty acid (FFA) assay kit (catalogue # Ab65341) was used for the liver FFA measurements.