Point-of-care tests: where is the point?
Authors: Thomas Hänscheid, Maria Rebelo, Martin P Grobusch
Journal: The Lancet Infectious Diseases (2014)

A recurrent theme in the Review by Paul Drain and colleagues1Drain PK Noubary F Freedberg KA et al.Diagnostic point-of-care tests in resource limited settings.Lancet Infect Dis. 2014; 14: 239-249Summary Full Text Full Text PDF PubMed Scopus (488) Google Scholar is the dichotomy between point-of-care (POC) tests and their laboratory counterparts, which implies that these tests can be used outside the laboratory. Certainly, rapid diagnostic tests (RDTs) for malaria are an example of a POC test; however, loop-mediated isothermal amplification (LAMP) for malaria has also been touted as a possible POC test.2Cordray MS Richards-Kortum RR Emerging nucleic acid-based tests for point- of-care detection of malaria.Am J Trop Med Hyg. 2012; 87: 223-230Crossref PubMed Scopus (106) Google Scholar, 3Abdul-Ghani R Al-Mekhlafi AM Karanis P Loop-mediated isothermal amplification (LAMP) for malarial parasites of humans: would it come to clinical reality as a point-of-care test?.Acta Trop. 2012; 122: 233-240Crossref PubMed Scopus (87) Google Scholar This discrepancy raises an important question: where is the point of care? For example, GeneXpert (Cepheid, CA, USA) MTB/RIF needs basic laboratory infrastructure, shifting the POC from a remote area to a peripheral laboratory.4Pai NP Vadnais C Denkinger C Engel N Pai M Point-of-care testing for infectious diseases: diversity, complexity, and barriers in low- and middle-income countries.PLoS Med. 2012; 9: e1001306Crossref PubMed Scopus (442) Google Scholar By contrast, RDTs allow efficient diagnosis of malaria at the POC, even in remote communities, far away from laboratories or hospitals. Despite the analytical advantage of nucleic acid-based tests like LAMP, basic laboratory infrastructure is needed, meaning that it cannot be used at the same proximity to the POC as RDTs can. Authors of one review define the setting where POC tests can be used, ranging from home to community, health post, peripheral laboratory, and finally hospital.4Pai NP Vadnais C Denkinger C Engel N Pai M Point-of-care testing for infectious diseases: diversity, complexity, and barriers in low- and middle-income countries.PLoS Med. 2012; 9: e1001306Crossref PubMed Scopus (442) Google Scholar Malaria tests are deemed POC tests in four of these five categories. Oddly, this approach seems to turn almost any existing malaria diagnostic test into a POC test, and the POC into a so-called area of care, which is somehow contradictory in itself. The effect of this approach is the inflationary use of the term POC test because there is little, if any, difference to a standard laboratory-based test. Where or what is the POC for malaria patients, and what defines it? At least, tests would need to have some quantifiable degree of suitability for being a POC test? On the Foundation for Innovative New Diagnostics website,5Foundation for innovative new diagnostics, About us.http://www.finddiagnostics.org/aboutGoogle Scholar LAMP is categorised as a "district and sub-district level" test, whereas the term POC is mentioned in the context of RDTs. These questions are not mundane because the term point-of-care could be no longer useful. The term could even be misused in an attempt to capture increasingly competitive research funding or could misinform implementation strategies in times of tight budgets. In conclusion, and notwithstanding the many useful suggestions, criteria, and definitions provided, we believe that the otherwise highly valuable review by Drain and colleagues should have addressed this POC (point of consideration) more elaborately. We declare no competing interests. Diagnostic point-of-care tests in resource-limited settingsThe aim of diagnostic point-of-care testing is to minimise the time to obtain a test result, thereby allowing clinicians and patients to make a quick clinical decision. Because point-of-care tests are used in resource-limited settings, the benefits need to outweigh the costs. To optimise point-of-care testing in resource-limited settings, diagnostic tests need rigorous assessments focused on relevant clinical outcomes and operational costs, which differ from assessments of conventional diagnostic tests. Full-Text PDF