Perspective 2019

10 PERSPECTIVE 2019 The use of biochemical testing to support clinical decision making has grown extensively. However, in some hospitals certain analytes are still not routinely tested in-house. Patient samples are sent away to a referral laboratory for analysis or are stored and batch tested once or twice a week. This means that it can take several weeks before a result is available. Treatment decisions often have to be made without the benefit of the analyte information, or potentially more invasive and costly procedures must be performed to help determine the most appropriate course of action. In these situations Point-of-Care (POC) testing can add significantly to the management of patients. By streamlining the diagnostic process it enables rapid triage, helping to ensure appropriate, more timely treatment decisions are made. In addition to the healthcare benefits, POC testing also offers patients the benefit of direct discussion of test results with their clinician and the determination of an appropriate treatment plan. These factors can significantly relieve patient anxiety that delays from traditional laboratory testing can cause. Rapid Drug Monitoring Serum trough levels for biologics are extremely useful in determining effective treatment, as these compounds are prone to either a primary loss of response or a loss of response over time. Historically testing has been performed by ELISA methods which necessitate batch testing in order to be cost efficient. Batch testing inevitably introduces a delay in obtaining the result which is compounded by the fact that few hospitals run the analysis themselves – most use a referral service which can add further delays of up to several weeks. Consequently patients may have been administered multiple further drug doses before the delivery can be optimised into the therapeutic window. In a poster presented by C. Rentsch1 at ECCO 2018, 77% of patients required dose adjustment based on the serum trough levels achieved after the first dose, with 51% requiring dose reduction and 26% requiring dose escalation. In the absence of timely trough level information these patients are likely to receive subsequent doses without the appropriate adjustment therefore compounding the situation. Anti-TNFα POC The BÜHLMANN Quantum Blue® Infliximab and Adalimumab assays enable rapid, individual testing of serum samples to give trough level results in about an hour. This allows proactive management of patients through adjustment of the next dose to a more appropriate level. Obtaining rapid results for serum drug levels not only enables optimisation of treatment, minimising loss of response and side effects but also saves valuable healthcare resources. The Quantum Blue TDM assays are simple to run and are read using a small bench top device. They can be performed in the laboratory or infusion clinic to give quantitative results in around an hour. Studies have shown that the results using the rapid method are comparable to the traditional laboratory ELISA test result2,3. Tests can be performed in the laboratory, but when performed by nurses in the clinic they still have a good correlation to the laboratory result [Figure1]3 . The total test time is ~ 1 hour (actual assay time is 15 minutes). This offers the opportunity for patients to come to their appointment and have bloods taken for analysis by the nurse in the infusion clinic. They can wait for the results and have their next drug dose optimised based on the test data. Are You Fed-up Waiting for Results? Get Answers Faster with Point-of-Care Testing “[Quantum Blue] is a good alternative for the conventional ELISA method for the measurement of IFX serum concentrations at trough in IBD.2” Strik et al. “This rapid test strategy has the potential to reduce patient risks and improve patient outcomes without negative cost implications1” Rentsch et al. “The test can accurately be performed by a nurse which means that TDM now can be moved from a distant laboratory to the near patient facility like the infusion centre and ensure correct dosing in IBD and other patients on IFX treatment.3” Lindsjo et al. Quantum Blue® Infliximab / Lay-user (µg/ml) Reference Laboratory (NRD, µg/ml) Figure 1: Correlation of the results obtained with the QB-IFX rapid test done by a nurse and a lab person. r = 0.92, p < 0.001