PubMed | University of Missouri, University of Toronto, DynaLIFE DX Diagnostic Laboratory Services, Emory University and Location Queen Beatrix Hospital
Type: | Journal: Clinica chimica acta; international journal of clinical chemistry | Year: 2016
Hemoglobin C, D Punjab, E or S trait can interfere with hemoglobin A1c (HbA1c) results. We assessed whether they affect results obtained with 12 current assay methods.Hemoglobin AA (HbAA), HbAC, HbAD Punjab, HbAE and HbAS samples were analyzed on one enzymatic, nine ion-exchange HPLC and two Capillary Electrophoresis methods. Trinity ultra(2) boronate affinity HPLC was the comparative method. An overall test of coincidence of least-squared linear regression lines was performed to determine if HbA1c results were statistically significantly different from those of HbAA samples. Clinically significant interference was defined as >7% difference from HbAA at 6 or 9% HbA1c compared to ultra(2) using Deming regression.All methods showed statistically significant effects for one or more variants. Clinically significant effects were observed for the Tosoh G8 variant mode and GX (all variants), GX V1.22 (all but HbAE) and G11 variant mode (HbAC). All other methods (Abbott Architect c Enzymatic, Bio-Rad D-100, Variant II NU and Variant II Turbo 2.0, Menarini HA-8180T thalassemia mode and HA-8180V variant mode, Sebia Capillarys 2 and Capillarys 3) showed no clinically significant differences.Several methods showed clinically significant interference with HbA1c results from one or more variants which could adversely affect patient care.
Bigras G.,University of Alberta |
Wilson J.,DynaLIFE DX Diagnostic Laboratory Services |
Russell L.,University of Alberta |
Johnson G.,DynaLIFE DX Diagnostic Laboratory Services |
And 2 more authors.
Cytopathology | Year: 2013
Objectives: Given the well-known poor reproducibility of cervical cytology diagnosis, especially for atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL), this study surveyed reproducibility in the assessment of individual cytomorphological features. Methods: One hundred and fifty cells or groups of cells, with a variety of morphological appearances, including normal cells, high-grade squamous intraepithelial lesion (HSIL), LSIL, ASC-US and ASC cannot exclude HSIL (ASC-H), were precisely marked on 150 different liquid-based cytological preparations. They were analysed by 17 observers who assessed 17 cytological features including nuclear features (chromatin texture, nuclear outline, nuclear shape, etc.), cytoplasmic features (cell shape, cytoplasmic staining, cytoplasmic clearing, etc.) and group characteristics (nuclear polarity, cellular density, etc.). A total of 43350 data scores were collected in a database using a web-based survey. Kendall's W and relative entropy indexes were utilized to compute concordance indexes of respectively ordinal and nominal variables. Results: Nuclear features have significantly lower reproducibility (0.46) compared with other cytological features (0.59). The feature with least agreement is assessment of chromatin texture. A small but significant difference in concordance was found between two subsets of observers with different levels of experience. Conclusion: Most previous studies assessing reproducibility of cytological diagnoses show, at best, moderate reproducibility among observers. This study focused on agreement regarding the presence of constituent morphological features used to recognize dyskaryosis and various grades of squamous intraepithelial lesions. A map of reproducibility indexes is presented that highlights, for daily practice or teaching, the robustness of features used for cytological assessment, recognizing that diagnosis is always based on a combination of features. © 2011 Blackwell Publishing Ltd.
PubMed | Calgary Laboratory Services, University of Alberta, DynaLIFE DX Diagnostic Laboratory Services and Regina QuAppelle Health Region
Type: Journal Article | Journal: Clinical biochemistry | Year: 2015
The World Health Organization and the American and Canadian Diabetes Associations approved HbA1c >6.5% as diagnostic for type 2 diabetes mellitus (T2DM). Hb variants and/or their chemically modified species can interfere with HbA1c measurements. We recently described a patient with Hb Wayne trait who was misdiagnosed with T2DM based on falsely elevated HbA1c. Hb Wayne is a clinically silent variant that exists as two isoforms: Hb Wayne I (Asn 139) and Hb Wayne II (Asp 139).Hemoglobinopathy investigation was performed by HPLC (Bio-Rad VARIANT-II), alkaline and acid electrophoresis (Sebia Hydrasis2), capillary zone electrophoresis (Sebia CAPILLARYS2) and DNA sequencing. HbA1c was measured by five methods.Hb Wayne eluted as two small fractions with retention times of 1.0 and 1.46min on the HPLC (Bio-Rad VARIANT-II). Alkaline gel and capillary electrophoresis showed two small bands migrating faster than HbA. Hb Wayne generated spuriously high results on the Bio-Rad VARIANT-II Turbo 2.0, no results on the Tosoh G8, and did not interfere with either the Sebia CAPILLARYS2 or immunoassays from Roche (tinaquant) and Siemens (Bayer DCA2000+). Based on the Hb Wayne HPLC profile of 3 patients, an algorithm was developed to facilitate its detection, which identified 9 additional patients with Hb Wayne trait.We characterize Hb Wayne by chromatographic and electrophoretic techniques and show the effect of Hb Wayne on five common HbA1c methodologies. We developed a quality assurance tool to assist in detecting Hb Wayne trait during HbA1c analysis on the Bio-Rad VARIANT-II Turbo 2.0.
Battochio A.,University of Alberta |
Mohammed S.,University of Alberta |
Winthrop D.,University of Alberta |
Lefresne S.,University of Alberta |
And 4 more authors.
American Journal of Clinical Pathology | Year: 2010
Mutational analysis of c-KIT or PDGFRA has become an important laboratory assay for patients with gastrointestinal stromal tumors (GISTs) because the results are useful in predicting the responsiveness to imatinib. To assess the diagnostic usefulness of denaturing high-pressure liquid chromatography (DHPLC) in this setting, we performed DHPLC and DNA sequencing to study exons 9, 11, 13, and 17 of c-KIT and exons 12 and 18 of PDGFRA in 54 consecutive cases of GIST collected from a single population. Most (40/54 [74%]) carried c-KIT mutations, and 7 (13%) carried PDGFRA mutations. These results were similar to those described in the literature. It is important to note that DHPLC was found to be highly sensitive, detecting all of the mutations in these 6 exons that were identified by DNA sequencing. Our data suggest that DHPLC is a costeffective, rapid, and sensitive test for screening for mutations of c-KIT and PDGFRA in GISTs. © American Society for Clinical Pathology.
PubMed | University of Alberta, DynaLIFE DX Diagnostic Laboratory Services and Alberta Health Services
Type: Journal Article | Journal: Clinical biochemistry | Year: 2015
To report the finding of a novel double heterozygous hemoglobinopathy, the coinheritance of Hb Fontainebleau (-chain variant) with HbD-Punjab (-chain variant) discovered upon investigation of unexplained microcytosis in an infant.Hemoglobinopathy investigation was performed by high performance liquid chromatography (HPLC) using the -thalassemia Short Program on the Bio-Rad Variant II(TM) followed by gel electrophoresis at alkaline and acid pH (Sebia Hydrasys 2 Electrophoresis System) and molecular diagnostic testing. This study complied with our institutional board ethics requirements.HPLC and electrophoresis suggested a complex - and -chain hemoglobinopathy with presumptive identification of the beta Hb variant as Hb D-Punjab. DNA sequencing analysis revealed the presence of a double heterozygous status for Hb Fontainebleau/Hb D-Punjab.In this paper we report the coinheritance of Hb Fontainebleau with Hb D-Punjab.
Rodriguez-Capote K.,DynaLIFE Dx Diagnostic Laboratory Services |
Rodriguez-Capote K.,University of Alberta |
Estey M.P.,DynaLIFE Dx Diagnostic Laboratory Services |
Estey M.P.,University of Alberta |
And 7 more authors.
Clinical Biochemistry | Year: 2015
Objectives: To report the finding of a novel double heterozygous hemoglobinopathy, the coinheritance of Hb Fontainebleau (α-chain variant) with HbD-Punjab (β-chain variant) discovered upon investigation of unexplained microcytosis in an infant. Design and methods: Hemoglobinopathy investigation was performed by high performance liquid chromatography (HPLC) using the β-thalassemia Short Program on the Bio-Rad Variant IITM followed by gel electrophoresis at alkaline and acid pH (Sebia Hydrasys 2 Electrophoresis System) and molecular diagnostic testing. This study complied with our institutional board ethics requirements. Results: HPLC and electrophoresis suggested a complex α- and β-chain hemoglobinopathy with presumptive identification of the beta Hb variant as Hb D-Punjab. DNA sequencing analysis revealed the presence of a double heterozygous status for Hb Fontainebleau/Hb D-Punjab. Conclusions: In this paper we report the coinheritance of Hb Fontainebleau with Hb D-Punjab. © 2015 The Canadian Society of Clinical Chemists.
PubMed | University of Alberta and DynaLIFE DX Diagnostic Laboratory Services
Type: Journal Article | Journal: Clinical biochemistry | Year: 2016
To determine the optimum storage temperature for serum allergen specific IgE antibodies (sIgE) to common food and inhalant allergens.Patient sera with sIgE concentrations 0.7kIUMinimal effects on specimen stability were noted for all sIgE analyzed under the three storage conditions tested in this study. All changes observed in sIgE concentrations were related to the assay variability and not to sample deterioration.Serum allergen specific IgE concentrations are stable at all temperatures studied for up to 17days.