Furthermore, many laboratories in low-resource settings may not meet CLIA or similar regulatory standards for proficiency testing, incorporation of standardized controls, etc. But certification under these frameworks is not the same as FDA approval. Compliance with CLIA requires validation and quality assurance for all laboratory tests used in clinical care, including “laboratory-developed tests.” The Clinical and Laboratory Standards Institute (CLSI) also issues “Guidelines-CLSI Molecular Diagnostic Methods for Infectious Diseases” ( CLSI, 2015). CLIA laboratories are certified by inspection by an agency such as the College of American Pathology. It sets minimum standards under which all clinical laboratories operate. In the United States, a regulatory framework, the Clinical Laboratory Improvement Amendments (CLIA), guides clinical laboratory testing. National Institute of Standards and Technology, the World Health Organization (WHO), and various nongovernmental organizations) have not yet done so for most of the new molecular technologies. In addition, the entities that normally certify and/or approve such tests (e.g., the U.S. Because of this lack of standardization, the same assay run in two different labs may yield different results, and confirmatory testing is slow and costly. Chiu reviewed some areas in which standards for molecular testing are lacking, particularly for environments that are not highly regulated: positive and negative controls, platforms, analytical performance, target pathogens, and reference databases.
Second, performance assessment, validation, and regulatory approval of many of these methods are challenging, especially if the work is performed outside of highly controlled clinical laboratory environments, which may not be available in low-resource settings. One participant noted, for example, that the cost of one PCR kit equals about 1 year’s salary for a lab worker in low-resource settings. First, these methods are more expensive than classical techniques. Chiu continued, molecular testing also has significant disadvantages. Molecular methods also offer faster turnaround time and do not require large sample volumes. Because such molecular-based testing enables performance of diagnostics with noninfectious inactivated pathogens, the need for costly and complex BSL-3 or -4 containment is obviated for diagnostic work on very hazardous pathogens. They do not rely on culture-based amplification, which is important because many pathogensĪre not culturable.
The pathogens are inactivated for testing, so handling them is safer than in methods that require the use of infectious live organisms, decreasing the potential for occupational exposures. Molecular diagnostic tests offer some advantages for low-resource settings.
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