Evaluation of the Alere Afinion™ AS100 for measuring the levels of C-Reactive Protein in an aged population.

Abstract

Introduction The Alere Afinion™ AS100 analyser is a compact bench-top, multi-assay, point-of-care (POC) analyser that provides valuable near patient testing at the point of care. It utilises the latest technology to measure C-Reactive Protein and other analytes to monitor patients’ disease progression. The main objective of the study was to evaluate the performance of the Alere Afinion™ AS100 analyser compared with a reference laboratory test method, ABX Pentra 400 for the measurement of C-Reactive Protein (CRP). Methods This study was a retrospective analysis in which stored serum samples obtained from a cross-sectional study referred to as Sexual Health, HIV infection and comorbidity with non-communicable diseases among Older Persons (SHIOP) were tested for the quantification of the CRP. The primary aim of SHIOP was to describe sexuality, sexual health and the comorbidity of HIV and sexually transmitted infections with chronic non-communicable diseases in adults aged ≥50 years in a setting of high HIV prevalence. Serum stored at -20 ⁰C from participants that consented to long term storage(n=183) was used to perform this evaluation. The serum samples were used to measure CRP on the Alere Afinion™ AS100 and ABX Pentra 400, respectively. Lin’s correlation coefficient was used to assess the agreement between the two analysers for the measurement of CRP. Risk factors associated with elevated CRP levels were assessed through this study. Results A total of 183 serum samples were tested in the study. The mean age of the study participants was 7.62 years (SD 8.15). Male participants were slightly older than female participants (61 vs 58years, p<0.05). Approximately 14.2% of study participants were above 70 years of age. The study population consisted of 77/183 (42%) Black South Africans and 106/183 (57.9%) Indians. The Alere Afinion™ AS100 was able to correctly classify (165/183) >90% of the CRP results when compared to the ABX Pentra 400. Bland-Altman analysis and linear regression analysis showed an excellent agreement (correlation concordance 0.97) between the two analysers. This study showed that being obese (Odds Ratio [OR]: 1.98, 95% Confidence Interval [CI]: 1.3616, 2.889, p<0.001) and having low HDL levels (OR: 1.64, 95% CI: 1.158, 2.307, p= 0.005) were the only significant risk factors that were associated with elevated CRP levels. Conclusion This study showed that the Alere Afinion™ AS100 can be used for the measurement of CRP in instances where CRP is greater than 5mg/L and this may enhance the process of patient care and management in low resource settings. Keywords: C-Reactive Protein (CRP), Affinion AS100, Sexual Health, HIV infection and comorbidity with non-communicable diseases among Older Persons (SHIOP), ABX Pentra 400.