Multicenter comparison of automated procalcitonin immunoassays

Abstract

ObjectivesA multicenter study to compare results of BRAHMS Kryptor PCT with those obtained using four BRAHMS-partnered procalcitonin (PCT) automated immunoassays (DiaSorin Liaison, BioMérieux Vidas, Roche Cobas E601 and Siemens Advia Centaur) and the Diazyme immunotubidimetric assay implemented on four clinical chemistry platforms (Abbott Architect c16000, Siemens Advia 2400, Roche Cobas C501 and Beckman Coulter AU5800).Design and methodsOne hundred serum samples from in-patients with PCT values between 0.10 and 58.7 ng/mL were divided into aliquots and tested with the nine different reagents and analyzers. BRAHMS PCT Kryptor results were used as reference.ResultsCompared to BRAHMS PCT Kryptor, significant differences in results were observed on Vidas, Advia Centaur, Architect, Cobas C501 and AU5800. However, the correlation coeffiecients (r) with BRAHMS PCT Kryptor were between 0.899 and 0.988. The mean bias was less than ±1.02 ng/mL, except for Vidas (2.70 ng/mL). The agreement at three clinically relevant cut-offs was optimal: between 83–98% at 0.50 ng/mL, 90–97% at 2.0 ng/mL, and 98% at 10 ng/mL. The comparison of Diazyme PCT across the four clinical chemistry analyzers yielded high correlation coefficients (r between 0.952 and 0.976), a mean bias less than ±0.9 ng/mL, acceptable agreement at 0.5 ng/mL (>82%), and high concordance at the 2.0 ng/mL (>97%) and 10 ng/mL (>98%) cut-offs.ConclusionsThe methods and applications evaluated in this multicenter study are aligned with BRAHMS PCT Kryptor and can be used for predicting the risk of progression to systemic inflammation in patients with bacterial infections using the conventional PCT diagnostic thresholds.

Diagnostic Accuracy of Procalcitonin Compared to C-Reactive Protein and Interleukin 6 in Recognizing Gram-Negative Bloodstream Infection: A Meta-Analytic Study

“…In our subgroup analysis, we failed to get exact age and sex information from some of the studies, which hindered the analytical process going further [21,26,31,33,36,37,40,41,54]. Our results assessing the performance of different PCT assays were in line with previous studies which demonstrated equivalence among 3 different PCT assays (Kryptor, Vidas, or Elecsys/-Cobas), as the threshold and accuracy were suggested consistent across these three tests in our study [55,56]. A study comparing recent popular PCT assay systems showed the results from these systems correlated well, but their regression lines varied considerably.…”

Procalcitonin measurement to screen medullary thyroid carcinoma: A prospective evaluation in a series of 2705 patients with thyroid nodules

“…Notably, even if differently available PCT immunoassays produce consistent analytical result several studies have been carried out to evaluate the analytical performance and the possible implications on clinical classification of patients using different methods. 36 Overall, the published studies showed a satisfactory analytical alignment between BRAHMS PCT Kryptor and the other methods (r ≥ .9) with good agreements (>80%) in patient classification at the 3 conventional diagnostic thresholds for diagnosis of bacterial infections 0.50, 2.0 and 10 ng/mL, 37 but the unavoidable modest analytical bias between different IMAs suggests the use of the same method for longitudinal patient monitoring. In addition, no data on agreement between different methods are available in patients carrying thyroid nodules and MTC.…”

Analytical Evaluation of the New Beckman Coulter Access Procalcitonin (PCT) Chemiluminescent Immunoassay

“…The results of the comparison study with BRAHMS PCT-sensitive Kryptor were especially surprising and favorable. Overall, the correlation coefficient was excellent (i.e., r = 0.999; p < 0.001) and the bias extremely limited, lower than 5% (i.e., 3.2%), and thus even better than those frequently observed when comparing other methods using the same BRAHMS anti-PCT monoclonal antibodies [12,13,16,17]. Identical conclusions can be made for diagnostic agreement at the three clinical decision thresholds, whereby global agreement between Access PCT and BRAHMS PCT-sensitive Kryptor was always ≥98%, again, better than comparative methods based on BRAHMS anti-PCT monoclonal antibodies.…”

“…The well-established value of PCT measurement in many infectious conditions and across a kaleidoscope of healthcare settings has strongly contributed to development of analytical techniques for its measurement [11]. More specifically, a large number of fully-automated immunoassays have become commercially available during the past decade, employing different assay formats (i.e., enzymatic, luminescent, fluorescent, chemiluminescent and turbidimetric immunoassays) [12][13][14][15][16][17][18][19]. Since the clinical management of patients with severe infections and/or sepsis is always critical and time-dependent, the availability of fully-automated PCT immunoassays is now virtually unavoidable, and these techniques enable an excellent balance between high throughput, short turnaround time, low sample volume (which is always crucial in critical patients needing repeated blood collections) and reasonable costs.…”