1
|
Brukner I, Resendes A, Eintracht S, Papadakis AI, Oughton M. Sample Adequacy Control (SAC) Lowers False Negatives and Increases the Quality of Screening: Introduction of "Non-Competitive" SAC for qPCR Assays. Diagnostics (Basel) 2021; 11:diagnostics11071133. [PMID: 34206413 PMCID: PMC8305439 DOI: 10.3390/diagnostics11071133] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/15/2021] [Accepted: 06/20/2021] [Indexed: 01/15/2023] Open
Abstract
Sample Adequacy Control (SAC) has critical analytical, clinical and epidemiological value that increases confidence in a negative test result. The SAC is an integral qPCR assay control, which ensures that all pre-analytical and analytical steps are adequate for accurate testing and reporting. As such, a negative SAC with a negative result on pathogen screen specifies that the result should be reported as inconclusive instead of negative. Despite this, many regulatory approved tests do not incorporate SAC into their assay design. Herein, we emphasize the universal value of SAC and offer for the first time, a simple technical strategy to introduce non-competitive SAC which does not interfere with the limit of detection for the screened pathogen. Integration of SAC can provide key benefits towards identifying, isolating, quarantining and contact tracing infected individuals and in turn can improve worldwide efforts in infection control.
Collapse
Affiliation(s)
- Ivan Brukner
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; (A.R.); (A.I.P.)
- Faculty of Medicine, McGill University, Montreal, QC H3A 0G4, Canada;
- Correspondence: (I.B.); (M.O.); Tel.: +1-514-8038782 (I.B.); +1-514-3408222 (ext. 22662) (M.O.)
| | - Alex Resendes
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; (A.R.); (A.I.P.)
| | - Shaun Eintracht
- Faculty of Medicine, McGill University, Montreal, QC H3A 0G4, Canada;
| | - Andreas I. Papadakis
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; (A.R.); (A.I.P.)
| | - Matthew Oughton
- Faculty of Medicine, McGill University, Montreal, QC H3A 0G4, Canada;
- Correspondence: (I.B.); (M.O.); Tel.: +1-514-8038782 (I.B.); +1-514-3408222 (ext. 22662) (M.O.)
| |
Collapse
|
2
|
Watson EJ, Templeton A, Russell I, Paavonen J, Mardh PA, Stary A, Pederson BS. The accuracy and efficacy of screening tests for Chlamydia trachomatis: a systematic review. J Med Microbiol 2002; 51:1021-1031. [PMID: 12466399 DOI: 10.1099/0022-1317-51-12-1021] [Citation(s) in RCA: 139] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Screening women for lower genital tract infection with Chlamydia trachomatis is important in the prevention of pelvic inflammatory disease, ectopic pregnancy and infertility. This systematic review aims to state clearly which of the available diagnostic tests for the detection of C. trachomatis would be most effective in terms of clinical effectiveness. The review included all studies published from 1990 onward that evaluated diagnostic tests in asymptomatic, young, sexually active populations. Medline and Embase were searched electronically and key journals were hand-searched. Further studies were identified through the Internet and contact with experts in the field. All studies were reviewed by two reviewers and were scored by Irwig's assessment criteria. Additional quality assessment criteria included a documented sexual history and recording of previous chlamydial infection. The reviews were subjected to meta-analysis and meta-regression. The 30 studies that were included examined three types of DNA-based test--ligase chain reaction (LCR), PCR and gene probe--as well as enzyme immuno-assay (EIA). The results showed that while specificities were high, sensitivities varied widely across the tests and were also dependent on the specimen tested. Pooled sensitivities for LCR, PCR, gene probe and EIA on urine were 96.5%, 85.6%, 92% and 38%, respectively, while on cervical swabs the corresponding sensitivities of PCR, gene probe and EIA were 88.6%, 84% and 65%. Meta-analysis demonstrated that DNA amplification techniques performed best for both urine and swabs in low prevalence populations. We conclude that nucleic acid amplification tests used on non-invasive samples such as urine are more effective at detecting asymptomatic chlamydial infection than conventional tests, but there are few data to relate a positive result with clinical outcome.
Collapse
Affiliation(s)
| | | | - Ian Russell
- Department of Obstetrics and Gynaecology, Aberdeen University, Aberdeen, Scotland, *Department of Health Sciences and Clinical Evaluation, University of York, York, UK, †Department of Obstetrics and Gynaecology, Helsinki University, Helsinki, Finland, Department of Clinical Bacteriology, University of Uppsala, Uppsala, Sweden, §Ambulatorium fur Pilzinfektionen, Vienna, Austria and ∥Department of Obstetrics and Gynaecology, Oslo University Hospital, Oslo, Norway
| | - Jorma Paavonen
- Department of Obstetrics and Gynaecology, Aberdeen University, Aberdeen, Scotland, *Department of Health Sciences and Clinical Evaluation, University of York, York, UK, †Department of Obstetrics and Gynaecology, Helsinki University, Helsinki, Finland, Department of Clinical Bacteriology, University of Uppsala, Uppsala, Sweden, §Ambulatorium fur Pilzinfektionen, Vienna, Austria and ∥Department of Obstetrics and Gynaecology, Oslo University Hospital, Oslo, Norway
| | - Per-Anders Mardh
- Department of Obstetrics and Gynaecology, Aberdeen University, Aberdeen, Scotland, *Department of Health Sciences and Clinical Evaluation, University of York, York, UK, †Department of Obstetrics and Gynaecology, Helsinki University, Helsinki, Finland, Department of Clinical Bacteriology, University of Uppsala, Uppsala, Sweden, §Ambulatorium fur Pilzinfektionen, Vienna, Austria and ∥Department of Obstetrics and Gynaecology, Oslo University Hospital, Oslo, Norway
| | - Angelika Stary
- Department of Obstetrics and Gynaecology, Aberdeen University, Aberdeen, Scotland, *Department of Health Sciences and Clinical Evaluation, University of York, York, UK, †Department of Obstetrics and Gynaecology, Helsinki University, Helsinki, Finland, Department of Clinical Bacteriology, University of Uppsala, Uppsala, Sweden, §Ambulatorium fur Pilzinfektionen, Vienna, Austria and ∥Department of Obstetrics and Gynaecology, Oslo University Hospital, Oslo, Norway
| | - Babil Stray Pederson
- Department of Obstetrics and Gynaecology, Aberdeen University, Aberdeen, Scotland, *Department of Health Sciences and Clinical Evaluation, University of York, York, UK, †Department of Obstetrics and Gynaecology, Helsinki University, Helsinki, Finland, Department of Clinical Bacteriology, University of Uppsala, Uppsala, Sweden, §Ambulatorium fur Pilzinfektionen, Vienna, Austria and ∥Department of Obstetrics and Gynaecology, Oslo University Hospital, Oslo, Norway
| |
Collapse
|
3
|
Abstract
Abstract
Over the past several years, the development and application of molecular diagnostic techniques has initiated a revolution in the diagnosis and monitoring of infectious diseases. Microbial phenotypic characteristics, such as protein, bacteriophage, and chromatographic profiles, as well as biotyping and susceptibility testing, are used in most routine laboratories for identification and differentiation. Nucleic acid techniques, such as plasmid profiling, various methods for generating restriction fragment length polymorphisms, and the polymerase chain reaction (PCR), are making increasing inroads into clinical laboratories. PCR-based systems to detect the etiologic agents of disease directly from clinical samples, without the need for culture, have been useful in rapid detection of unculturable or fastidious microorganisms. Additionally, sequence analysis of amplified microbial DNA allows for identification and better characterization of the pathogen. Subspecies variation, identified by various techniques, has been shown to be important in the prognosis of certain diseases. Other important advances include the determination of viral load and the direct detection of genes or gene mutations responsible for drug resistance. Increased use of automation and user-friendly software makes these technologies more widely available. In all, the detection of infectious agents at the nucleic acid level represents a true synthesis of clinical chemistry and clinical microbiology techniques.
Collapse
Affiliation(s)
| | | | - David H Persing
- Division of Clinical Microbiology, Department of Pathology and Laboratory Medicine, Hilton Bldg. 470, Mayo Clinic, 200 First St., SW, Rochester, MN 55905
| |
Collapse
|