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Turvill JL, Turnock D, Cottingham D, Haritakis M, Jeffery L, Girdwood A, Hearfield T, Mitchell A, Keding A. The Fast Track FIT study: diagnostic accuracy of faecal immunochemical test for haemoglobin in patients with suspected colorectal cancer. Br J Gen Pract 2021; 71:e643-e651. [PMID: 33798091 PMCID: PMC8279659 DOI: 10.3399/bjgp.2020.1098] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/24/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The faecal immunochemical test (FIT) is now available to support clinicians in the assessment of patients at low risk of colorectal cancer (CRC) and within the bowel cancer screening programme. AIM To determine the diagnostic accuracy of FIT for CRC and clinically significant disease in patients referred as they were judged by their GP to fulfil National Institute for Health and Care Excellence guideline 12 (NG12) criteria for suspected CRC. DESIGN AND SETTING Patients referred from primary care with suspected CRC, meeting NG12 criteria, to 12 secondary care providers in Yorkshire and Humber were asked to complete a FIT before investigation. METHOD The diagnostic accuracy of FIT based on final diagnosis was evaluated using receiver operating characteristics analysis. This permitted a statistically optimal cut-off value for FIT to be determined based on the maximisation of sensitivity and specificity. Clinicians and patients were blinded to the FIT results. RESULTS In total, 5040 patients were fully evaluated and CRC was detected in 151 (3.0%). An optimal cut-off value of 19 µg Hb/g faeces for CRC was determined, giving a sensitivity of 85.4% (95% confidence interval [CI] = 78.8% to 90.6%) and specificity of 85.2% (95% CI = 84.1% to 86.2%). The negative predictive value at this cut-off value was 99.5% (95% CI = 99.2% to 99.7%) and the positive predictive value 15.1% (95% CI = 12.8% to 17.7%). Sensitivity and specificity of FIT for CRC and significant premalignant polyps at this cut-off value were 62.9% (95% CI = 57.5% to 68.0%) and 86.4% (95% CI = 85.4% to 87.4%), respectively; and when including all organic enteric disease were 35.7% (95% CI = 32.9% to 38.5%) and 88.6% (95% CI = 87.5% to 89.6%), respectively. CONCLUSION FIT used in patients fulfilling NG12 criteria should allow for a more personalised CRC risk assessment. FIT should permit effective, patient-centred decision-making to inform the need for, type, and timing of further investigation.
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Affiliation(s)
- James L Turvill
- Department of Gastroenterology, York and Scarborough Teaching Hospitals NHS Foundation Trust, York
| | - Daniel Turnock
- Department of Gastroenterology, York and Scarborough Teaching Hospitals NHS Foundation Trust, York
| | - Dan Cottingham
- Macmillan GP Cancer and End of Life lead, Vale of York Clinical Commissioning Group, West Offices Station Rise, York
| | - Monica Haritakis
- Department of Research and Development, York and Scarborough Teaching Hospitals NHS Foundation Trust, York
| | - Laura Jeffery
- Department of Research and Development, York and Scarborough Teaching Hospitals NHS Foundation Trust, York
| | - Annabelle Girdwood
- Department of Research and Development, York and Scarborough Teaching Hospitals NHS Foundation Trust, York
| | - Tom Hearfield
- Department of Research and Development, York and Scarborough Teaching Hospitals NHS Foundation Trust, York
| | - Alex Mitchell
- Department of Health Sciences, Faculty of Sciences, University of York, York
| | - Ada Keding
- Department of Health Sciences, Faculty of Sciences, University of York, York
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Benton SC, Symonds E, Djedovic N, Jones S, Deprez L, Kocna P, Maria Auge J. Faecal immunochemical tests for haemoglobin: Analytical challenges and potential solutions. Clin Chim Acta 2021; 517:60-65. [PMID: 33571484 DOI: 10.1016/j.cca.2021.01.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/14/2021] [Accepted: 01/27/2021] [Indexed: 12/24/2022]
Abstract
Quantitative faecal immunochemical tests for haemoglobin (FIT) are being used increasingly around the world in colorectal cancer screening programmes, and in patients presenting with lower bowel symptoms to determine who should proceed to further bowel visualisation investigations, usually colonoscopy. The clinical utility of FIT is well reported. There are a number of analytical challenges including pre-analytical variation, difficulty setting up external quality assessment schemes, access to third party internal quality control material and a lack of standardisation or harmonisation of FIT methods. Here we report the work of the International Federation of Clinical Chemistry FIT Working Group. We provide an overview of the main pre-analytical variables; discuss different approaches to external quality assurance of FIT; propose a solution to third party internal quality assurance materials and summarise the challenges of standardisation and harmonisation of FIT.
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Affiliation(s)
- Sally C Benton
- Clinical Biochemistry, Royal Surrey County Hospital/NHS Bowel Cancer Screening South of England Hub, Berkshire and Surrey Pathology Services, Guildford, Surrey, UK
| | - Erin Symonds
- Bowel Health Service, Flinders Medical Centre, Bedford Park, South Australia, Australia; Cancer Research, Flinders Health and Medical Research, Flinders University, Bedford Park, South Australia, Australia
| | - Natasha Djedovic
- Clinical Biochemistry/NHS Bowel Cancer Screening London Hub, London North West University Healthcare NHS Trust, UK
| | - Samantha Jones
- Weqas, Cardiff and Vale University Health Board, Cardiff, Wales, UK
| | - Liesbet Deprez
- European Commission, Joint Research Centre (JRC), Geel, Belgium
| | - Petr Kocna
- Laboratory of Gastroenterology, Institute of Medical Biochemistry and Laboratory Diagnostics, 1st.Medical Faculty of Charles University and General University Hospital, Prague, Czech Republic
| | - Josep Maria Auge
- Clinical Chemistry and Molecular Genetics Department, Hospital Clinic, Barcelona, Catalonia, Spain
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Piggott C, Carroll MRR, John C, O'Driscoll S, Benton SC. Analytical evaluation of four faecal immunochemistry tests for haemoglobin. Clin Chem Lab Med 2020; 59:173-178. [PMID: 32692692 DOI: 10.1515/cclm-2020-0251] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 06/29/2020] [Indexed: 12/21/2022]
Abstract
Objectives Faecal immunochemical tests (FIT) for haemoglobin (Hb) are being used in the investigation of colorectal cancer. These tests use antibodies raised to the globin moiety of human Hb. Here, four automated quantitative FIT systems (HM-JACKarc, NS-Prime, OC-Sensor PLEDIA and SENTiFIT 270) are evaluated analytically to confirm whether the performance of the systems meet the manufacturers' claims. Methods Assessment of the analytical performance of the FIT systems was undertaken using Hb lysates, real patient samples and external quality assessment (EQA) samples. This analytical assessment focused on detection characteristics, imprecision, linearity, prozone effect, recovery and carryover. Results All four methods demonstrated good analytical performance, with acceptable within- and between-run imprecision, good recovery of f-Hb and limited carryover of samples. They also all show good linearity across the range of concentrations tested. The results of EQA samples showed different variations from the target values (-52 to 45%), due to the absence of standardisation across the different methods. Conclusions All four systems are fit for purpose and have an analytical performance as documented by their manufacturers.
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Affiliation(s)
- Carolyn Piggott
- NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, England, UK.,Berkshire and Surrey Pathology Services,Royal Surrey County Hospital, Guildford, England, UK
| | - Magdalen R R Carroll
- NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, England, UK.,Berkshire and Surrey Pathology Services,Royal Surrey County Hospital, Guildford, England, UK
| | - Cerin John
- NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, England, UK.,Berkshire and Surrey Pathology Services,Royal Surrey County Hospital, Guildford, England, UK
| | - Shane O'Driscoll
- NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, England, UK.,Berkshire and Surrey Pathology Services,Royal Surrey County Hospital, Guildford, England, UK
| | - Sally C Benton
- NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, England, UK.,Berkshire and Surrey Pathology Services,Royal Surrey County Hospital, Guildford, England, UK
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Fraser CG, Benton SC. Detection capability of quantitative faecal immunochemical tests for haemoglobin (FIT) and reporting of low faecal haemoglobin concentrations. Clin Chem Lab Med 2019; 57:611-616. [PMID: 29995629 DOI: 10.1515/cclm-2018-0464] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/05/2018] [Indexed: 01/25/2023]
Abstract
Faecal immunochemical tests for haemoglobin (FIT) are widely used in asymptomatic population screening for colorectal (bowel) cancer. FIT are also used to assist with the assessment of patients presenting with lower abdominal symptoms. Quantitative FIT allow the generation of numerical estimates of faecal haemoglobin (f-Hb) concentrations. There is now great interest in "low" f-Hb concentrations in these clinical settings: in consequence, knowledge of the detection capability is very important for f-Hb concentration examinations. There are a number of current problems associated with the reporting of low f-Hb concentrations and wide misunderstanding of the metrological aspects of examinations of f-Hb at low concentrations. These would be solved if the detectability characteristics of f-Hb concentration examinations, namely, the limit of blank (LoB), limit of detection (LoD) and limit of quantitation (LoQ), were generated, validated and used in reporting systems exactly as recommended in the EP17-A2 guideline of the Clinical Laboratory Standards Institute. LoB and LoD are statistical concepts, but the LoQ depends on definition of analytical performance specifications (APS). In this Opinion Paper proposals for interim APS are made, based on the current state of the art achieved with examinations of faecal samples. It is proposed that LoQ is determined at an examination imprecision of CV≤10% using faecal samples naturally positive for Hb rather than faeces spiked with haemolysate. Detailed proposals for reporting f-Hb data at low concentrations are also made.
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Affiliation(s)
- Callum G Fraser
- Centre for Research into Cancer Prevention and Screening, University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, Scotland, UK
| | - Sally C Benton
- NHS Bowel Cancer Screening Programme, Southern Hub, Royal Surrey County Hospital NHS Foundation Trust, Guildford, Surrey, UK
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Turvill J, Mellen S, Jeffery L, Bevan S, Keding A, Turnock D. Diagnostic accuracy of one or two faecal haemoglobin and calprotectin measurements in patients with suspected colorectal cancer. Scand J Gastroenterol 2018; 53:1526-1534. [PMID: 30621475 DOI: 10.1080/00365521.2018.1539761] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND The role of faecal biomarkers in patients at 'high risk' of colorectal cancer (CRC) is not yet defined. Pre-analytical factors, such as heterogeneity of biomarker distribution within faeces, may influence their optimisation in clinical practice. We undertook to determine whether repeat or combined biomarker testing improves diagnostic accuracy for CRC or clinically significant disease. METHODS Patients referred with suspected CRC provided two separate faecal samples each for faecal immunochemical testing (FIT) and faecal calprotectin (FC) prior to investigation. Diagnostic accuracy of FIT and FC were evaluated based on final diagnoses. RESULTS Five hundred fifteen patients completed a full colorectal evaluation. The optimal cut-off for CRC using a single FIT was ≥12 µgHb/g faeces (84.6% sensitivity, 88.5% specificity). For two FIT, the cut-off was ≥43 µgHb/g faeces if either and ≥2 µgHb/g faeces if both were positive. There was no advantage in their diagnostic accuracy compared with a single FIT. FC had a lower diagnostic accuracy for CRC than FIT, which was not improved by repeat FC. No benefit was identified with FIT-FC combined. For CRC, significant adenomatous polyps and organic enteric disease combined, FIT and FC performed similarly to each other but were poorer predictors (AUC 0.677 and 0.660). There was no uplift in diagnostic accuracy when the tests were repeated or combined. CONCLUSION This study supports using a single FIT at a cut-off close to that recommended by NICE DG30 to improve diagnostic accuracy for 'two-week wait' patients referred with suspected CRC.
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Affiliation(s)
- James Turvill
- a Department of Gastroenterology , York Teaching Hospital NHS Foundation Trust , York , UK
| | - Samantha Mellen
- b Department of Clinical Biochemistry , York Teaching Hospital NHS Foundation Trust , York , UK
| | - Laura Jeffery
- b Department of Clinical Biochemistry , York Teaching Hospital NHS Foundation Trust , York , UK
| | - Sarah Bevan
- b Department of Clinical Biochemistry , York Teaching Hospital NHS Foundation Trust , York , UK
| | - Ada Keding
- c Department of Health Sciences, Faculty of Sciences , University of York , York , UK
| | - Daniel Turnock
- b Department of Clinical Biochemistry , York Teaching Hospital NHS Foundation Trust , York , UK
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Auge JM, Rodriguez C, Espanyol O, Rivero L, Sandalinas S, Grau J, Jimenez W, Castells A. An evaluation of the SENTiFIT 270 analyser for quantitation of faecal haemoglobin in the investigation of patients with suspected colorectal cancer. Clin Chem Lab Med 2018; 56:625-633. [PMID: 29150989 DOI: 10.1515/cclm-2017-0605] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/09/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND An evaluation of SENTiFIT® 270 (Sentinel Diagnostics, Italy; Sysmex, Spain) analyser for the quantitation of faecal haemoglobin (f-Hb) was performed. METHODS The analytical imprecision, linearity, carry over and f-Hb stability were determined. Evaluation of the diagnostic accuracy was performed on 487 patients. RESULTS Within-run and between-run imprecision ranged 1.7%-5.1% and 3.8%-6.2%, respectively. Linearity studies revealed a mean recovery of 101.1% (standard deviation, 6.7%) for all dilutions. No carry over was detected below 7650 μg Hb/g faeces. Decay of f-Hb in refrigerated samples ranged 0.2%-0.5% per day. f-Hb in patients with advanced colorectal neoplasia (ACRN) (colorectal cancer [CRC] plus advanced adenoma [AA]) were significantly higher than from those with a normal colonoscopy. Sensitivity for ACRN at f-Hb cutoffs from 10 to 60 μg Hb/g faeces ranged from 28.9% (95% confidence interval [CI], 21.7%-37.2%) to 46.5% (95% CI, 38.1%-55%), the specificity ranged from 85% (95% CI, 82.3%-87.3%) to 93.2% (95% CI, 91.2%-94.8%), positive predictive values for detecting CRC and AA ranged from 11.6% (95% CI, 7.6%-17.2%) to 20.6% (95% CI, 13.3%-30.3%) and from 34.7% (95% CI, 28.1%-42%) to 42.3% (95% CI, 32.4%-52.7%), respectively, and the negative predictive value for ACRN ranged from 90.2% (95% CI, 87.9%-92.2%) to 88.4% (95% CI, 86%-90.4%). Using two samples per patient sensitivity increased with a slight decrease in specificity. CONCLUSIONS The analytical and clinical performances of SENTiFIT assay demonstrate a specific and accurate test for detecting ACRN in symptomatic patients and those undergoing surveillance.
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Affiliation(s)
- Josep M Auge
- Biochemistry and Molecular Genetics Department, Biomedical Diagnostic Center, Hospital Clinic, C/Villarroel 170, 08036 Barcelona, Spain
| | - Cristina Rodriguez
- Gastroenterology Department, Hospital Clinic, University of Barcelona, Barcelona, Spain; and IDIBAPS, CIBERehd, Barcelona, Spain
| | - Oihana Espanyol
- Biochemistry and Molecular Genetics Department, Biomedical Diagnostic Center, Hospital Clinic, Barcelona, Spain
| | - Liseth Rivero
- Gastroenterology Department, Hospital Clinic, University of Barcelona, Barcelona, Spain; and IDIBAPS, CIBERehd, Barcelona, Spain
| | - Silvia Sandalinas
- Biochemistry and Molecular Genetics Department, Biomedical Diagnostic Center, Hospital Clinic, Barcelona, Spain
| | - Jaume Grau
- Unit of Evaluation, Support and Prevention, Hospital Clinic, Barcelona, Spain
| | - Wladimiro Jimenez
- Biochemistry and Molecular Genetics Department, Biomedical Diagnostic Center, Hospital Clinic, Barcelona, Spain
| | - Antoni Castells
- Gastroenterology Department, Hospital Clinic, University of Barcelona, Barcelona, Spain; and IDIBAPS, CIBERehd, Barcelona, Spain
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Carroll MR, John C, Mantio D, Djedovic NK, Benton SC. An assessment of the effect of haemoglobin variants on detection by faecal immunochemical tests. Ann Clin Biochem 2018; 55:706-709. [PMID: 29792044 DOI: 10.1177/0004563218778716] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Background Faecal immunochemical tests (FIT) for haemoglobin (Hb) are being used in the investigation of colorectal cancer. These tests use antibodies raised to the globin moiety of human Hb. Where the globin structure is abnormal or reduced, it is possible that antibody binding, and thus Hb-detection may be affected. Methods Lysates prepared from whole blood samples of patients with known variants were diluted in manufacturer-specific buffer to 10, 100 and 500 μg Hb/g faeces. These samples were analysed on four FIT analysers and the results compared with samples with no known variant present (normal samples). Results The results from this study show that of 20 variants tested, three showed a decrease in detection by all four analysers. These were β-thalassaemia major and two fetal cord blood samples. Conclusions Of 20 common Hb variants studied, 17 did not affect detection of Hb by the FIT systems tested. Hb variants leading to a reduction in the presence of a globin chain caused a reduction in Hb detection; in such cases, cancers could be missed.
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Affiliation(s)
- Magdalen Rr Carroll
- 1 NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, UK.,2 Berkshire and Surrey Pathology Services, Royal Surrey County Hospital, Guildford, UK
| | - Cerin John
- 1 NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, UK.,2 Berkshire and Surrey Pathology Services, Royal Surrey County Hospital, Guildford, UK
| | - Debbie Mantio
- 3 Haemoglobinopathy Screening Laboratory, The Doctors Laboratory, Central Middlesex Hospital-->, London, UK
| | - Natasha K Djedovic
- 4 Northwick Park Hospital, NHS Bowel Cancer Screening Programme London Hub, London, UK
| | - Sally C Benton
- 1 NHS Bowel Cancer Screening Programme Southern Hub, Royal Surrey County Hospital, Guildford, UK.,2 Berkshire and Surrey Pathology Services, Royal Surrey County Hospital, Guildford, UK
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Mellen S, de Ferrars M, Chapman C, Bevan S, Turvill J, Turnock D. Evaluation of sample stability for a quantitative faecal immunochemical test and comparison of two sample collection approaches. Ann Clin Biochem 2018. [DOI: 10.1177/0004563218766393] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Background Faecal immunochemical testing is increasingly being used to triage symptomatic patients for suspected colorectal cancer. However, there are limited data on the effect of preanalytical factors on faecal haemoglobin when measured by faecal immunochemical testing. The aim of this work was to evaluate the stability of faecal haemoglobin in faeces and to compare two methods of faecal haemoglobin sampling for faecal immunochemical testing. Methods Six patients provided faeces for faecal haemoglobin measurement which were transferred into specialized collection devices at baseline and at 1, 2, 3 and 7 days after storage at either room temperature or 4°C. A total of 137 patients returned both faeces transferred into the specialized collection device and faeces in a standard collection pot. A quantitative immunoturbidometric method was used to measure faecal haemoglobin and results were compared categorically. Discrepant results were assessed against diagnosis. Results Faecal haemoglobin concentration declined rapidly within a day of storage at room temperature but results remained ≥10 μg Hb/g faeces in 5/6 patients after two days. A faecal haemoglobin result ≥10 μg Hb/g faeces was obtained in 4/6 patients after storage for seven days at 4°C. Results obtained when patients used specialized collection devices were significantly different from results obtained when faeces was transferred into the specialized collection device in the laboratory. Conclusion There is considerable heterogeneity in the sample stability of faecal haemoglobin; therefore, samples should be transferred rapidly into specialized collection devices to prevent false-negative results. Use of collection devices by patients can lead to false-positive results compared with their use in a laboratory.
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Affiliation(s)
- Samantha Mellen
- Department of Clinical Biochemistry, York Teaching Hospital NHS Foundation Trust, York, UK
| | - Maria de Ferrars
- Department of Clinical Biochemistry, York Teaching Hospital NHS Foundation Trust, York, UK
| | - Claire Chapman
- Department of Clinical Biochemistry, York Teaching Hospital NHS Foundation Trust, York, UK
| | - Sarah Bevan
- Department of Clinical Biochemistry, York Teaching Hospital NHS Foundation Trust, York, UK
| | - James Turvill
- Department of Gastroenterology, York Teaching Hospital NHS Foundation Trust, York, UK
| | - Daniel Turnock
- Department of Clinical Biochemistry, York Teaching Hospital NHS Foundation Trust, York, UK
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Effects of Fecal Sampling on Preanalytical and Analytical Phases in Quantitative Fecal Immunochemical Tests for Hemoglobin. Int J Biol Markers 2017; 32:e261-e266. [DOI: 10.5301/ijbm.5000265] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/22/2017] [Indexed: 12/18/2022]
Abstract
Background Information on preanalytical variability is mandatory to bring laboratories up to ISO 15189 requirements. Fecal sampling is greatly affected by lack of harmonization in laboratory medicine. The aims of this study were to obtain information on the devices used for fecal sampling and to explore the effect of different amounts of feces on the results from the fecal immunochemical test for hemoglobin (FIT-Hb). Methods Four commercial sample collection devices for quantitative FIT-Hb measurements were investigated. The volume of interest (VOI) of the probes was measured from diameter and geometry. Quantitative measurements of the mass of feces were carried out by gravimetry. The effects of an increased amount of feces on the analytical environment were investigated measuring the Hb values with a single analytical method. Results VOI was 8.22, 7.1 and 9.44 mm3 for probes that collected a target of 10 mg of feces, and 3.08 mm3 for one probe that targeted 2 mg of feces. The ratio between recovered and target amounts of devices ranged from 56% to 121%. Different changes in the measured Hb values were observed, in adding increasing amounts of feces in commercial buffers. Conclusions The amounts of collected materials are related to the design of probes. Three out 4 manufacturers declare the same target amount using different sampling volumes and obtaining different amounts of collected materials. The introduction of a standard probes to reduce preanalytical variability could be an useful step for fecal test harmonization and to fulfill the ISO 15189 requirements.
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Lippi G, Plebani M. Opportunities and drawbacks of nonstandard body fluid analysis. ACTA ACUST UNITED AC 2017; 55:907-909. [DOI: 10.1515/cclm-2016-0862] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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