DynaLIFEDX

Edmonton, Canada

DynaLIFEDX

Edmonton, Canada

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Chui L.,Provincial Laboratory for Public Health | Chui L.,University of Alberta | Li V.,Provincial Laboratory for Public Health | Fach P.,Anses French Agency for Food | And 8 more authors.
Journal of Clinical Microbiology | Year: 2015

Virulence markers in Shiga toxin-producing Escherichia coli (STEC) and their association with diseases remain largely unknown. This study determines the importance of 44 genetic markers for STEC (O157 and non-O157) from human clinical cases and their correlation to disease outcome. STEC isolated from a cattle surveillance program were also included. The virulence genes tested were present in almost all O157:H7 isolates but highly variable in non-O157 STEC isolates. Patient age was a significant determinant of clinical outcome.


Ahmed-Bentley J.,University of Alberta | Chandran A.U.,University of Alberta | Chandran A.U.,Royal Alexandra Hospital | Joffe A.M.,University of Alberta | And 5 more authors.
Antimicrobial Agents and Chemotherapy | Year: 2013

Overseas travel, as a risk factor for the acquisition of infections due to antimicrobial-resistant organisms, has recently been linked to carbapenemase-producing Gram-negative bacteria. Multiresistant Klebsiella pneumoniae, Escherichia coli, and Acinetobacter baumannii strains were isolated from a wound of a Canadian patient with a recent history of hospitalization in India. This resulted in the initiation of outbreak management that included surveillance cultures. Epidemiological and molecular investigations showed that NDM-1-producing K. pneumoniae ST16 and OXA-23-producing A. baumannii ST10 strains were transmitted to 5 other patients, resulting in the colonization of 4 patients and the death of 1 patient due to septic shock caused by the OXA-23-producing A. baumannii strain. The high rate of false positivity of the screening cultures resulted in additional workloads and increased costs for infection control and clinical laboratory work. We believe that this is the first report of an infection with carbapenemase-producing Gram-negative bacteria resulting in death attributed to a patient with recent foreign hospitalization. We recommend routine rectal and wound screening for colonization with multiresistant bacteria for patients who have recently been admitted to hospitals outside Canada. Copyright © 2013, American Society for Microbiology.


Higgins T.,DynaLIFEDx | Schnabl K.,DynaLIFEDx | Savoy M.,DynaLIFEDx | Rowe P.,DynaLIFEDx | And 2 more authors.
Clinical Biochemistry | Year: 2012

Introduction: Hemoglobinopathies and thalassemias together form the most common genetic disease in the world. Double heterozygosity, in which there is a hemoglobin variant, in both the α- and non-α globin chains, is very unusual. A novel double heterozygosity of the α chain variant HbQ India with the non-α chain HbD Punjab is described. Methods and materials: The index case is a 39. year old female of Indian origin. HPLC analysis using the Bio Rad β thalassemia method and electrophoresis at both alkaline and acid pH were performed. Results: HPLC shows four major bands and electrophoresis at alkaline pH shows 3 bands and 2 bands at acid pH. Discussion: Both the HPLC and electrophoresis at alkaline and acid pH are consistent for the double heterozygous hemoglobin variants HbQ India and HbD Punjab. Conclusion: This is the first literature report of the double heterozygosity of HbQ India/HbD Punjab. © 2011 The Canadian Society of Clinical Chemists.


Kulkarni K.,University of Alberta | Rowe P.,DynaLIFEDx | Christensen C.L.,DynaLIFEDx | Higgins T.,DynaLIFEDx
Clinical Biochemistry | Year: 2012

Introduction: Bisalbuminemia is a genetic condition in which an albumin variant is found in serum in addition to normal albumin. Methods and materials: Serum protein electrophoresis using the Sebia HYDRASYS electrophoresis system was performed on an 84. year old male. Results: Serum protein electrophoresis showed a single albumin band migrating faster than normal albumin. Conclusion: The presence of a homozygous albumin variant band, albumin Naskapi, is noted. © 2011 The Canadian Society of Clinical Chemists..


Estey M.P.,DynaLIFEDx | Estey M.P.,University of Alberta | Rodriguez-Capote K.,DynaLIFEDx | Rodriguez-Capote K.,University of Alberta | And 2 more authors.
Clinical Biochemistry | Year: 2015

Objectives: To investigate the underlying cause of unexpectedly low HbA1c results (3.3-3.5%) obtained by HPLC in three siblings undergoing routine screening for type 2 diabetes mellitus. Design and methods: HbA1c was measured using an alternate method based on a different analytical principle (the Siemens DCA 2000. + immunoassay). Hemoglobin fractionation was performed by HPLC on the BioRad Variant II, gel electrophoresis at acid and alkaline pH on the Sebia Hydrasys 2, and capillary electrophoresis on the Sebia Capillarys 2. Sequencing of the beta globin gene was also conducted. Results: HbA1c analysis by immunoassay gave significantly higher results, ranging from 5.2-5.5%. Hemoglobin fractionation by HPLC showed an abnormal peak comprising approximately 43% of total hemoglobin, suggesting the presence of a beta chain hemoglobin variant. Gel electrophoresis at alkaline pH revealed a very unusual pattern, with 3 abnormal bands migrating with Hb F, between Hb F and Hb S, and slightly cathodal to Hb S. A single band in the Hb A position was seen on gel electrophoresis at acid pH. Capillary electrophoresis revealed two abnormal peaks, comprising 42% and 5% of total hemoglobin. Sequencing of the beta globin gene showed heterozygosity for Hb Hirose (beta 37(C3) Trp>Ser), an extremely rare variant with a substitution at the α1β2 interface. Conclusions: We describe the chromatographic and electrophoretic properties of Hb Hirose, and demonstrate that this rare variant causes falsely low HbA1c results on the BioRad variant II Turbo 2.0. Recognition of this interference is crucial in order to prevent reporting erroneous results. © 2015 The Canadian Society of Clinical Chemists.


Barakauskas V.E.,DynaLIFEDx | Barakauskas V.E.,University of Alberta | Lam G.Y.,University of Alberta | Estey M.P.,DynaLIFEDx | Estey M.P.,University of Alberta
Critical Reviews in Clinical Laboratory Sciences | Year: 2014

Celiac disease is a complex immune-mediated disorder that is triggered by ingestion of gluten and related proteins in genetically susceptible individuals. Under conditions of increased intestinal permeability, gluten-derived peptides can travel across the intestinal epithelium and undergo deamidation catalyzed by the tissue transglutaminase (TTG) enzyme. This renders them immunogenic in individuals expressing specific human leukocyte antigen (HLA) DQ heterodimers. The resulting immune response is characterized by the production of antibodies against both deamidated gliadin peptides (DGP) and TTG, generation of pro-inflammatory cytokines and activation of cytotoxic T cells. This response damages the intestinal epithelium resulting in the wide range of gastrointestinal and systemic symptoms observed in those with celiac disease. Celiac disease diagnosis has traditionally been based on biopsy and histological examination of the small intestine. While this approach is still considered the gold standard, it is invasive and susceptible to both false-positive and false-negative results. Several laboratory tests have become available to aid in the diagnosis and monitoring of celiac disease, and are the focus of this review. These include serological tests for celiac disease-specific antibodies such as anti-endomysial antibodies, anti-TTG antibodies and anti-DGP antibodies of both the immunoglobulin A (IgA) and immunoglobulin G (IgG) class, genetic tests to elucidate HLA DQ status and ancillary tests such as total IgA. While some have suggested that laboratory tests may replace intestinal biopsy in specific circumstances, others maintain that this procedure remains a critical component of celiac disease diagnosis. We review the analytical methodology, strengths, weaknesses, diagnostic performance and clinical utility of the various laboratory tests for celiac disease. Potential future markers and tests that are now considered obsolete are also discussed. Current clinical practice guidelines for the diagnosis and management of celiac disease from the European Society for Pediatric Gastroenterology, Hepatology and Nutrition, the American College of Gastroenterology and the World Gastroenterology Organisation are summarized, and important differences between these guidelines are highlighted. © 2014 Informa Healthcare USA, Inc.


Estey M.P.,DynaLIFEDX | Estey M.P.,University of Alberta | Belletrutti M.,University of Alberta | Rodriguez-Capote K.,DynaLIFEDX | And 2 more authors.
Clinical Biochemistry | Year: 2015

Objectives: 1)To investigate the presence of hemoglobin Constant Spring (HbCS) in a patient with severe microcytic anemia who had previously been diagnosed with alpha thalassemia minor.2)To assess the stability of HbCS post blood collection by high performance liquid chromatography (HPLC). Design and methods: Hemoglobin fractionation was performed by HPLC immediately after specimen collection using the β-thalassemia Short Program on the BioRad Variant II. To assess HbCS stability, the patient's specimen was re-analyzed over a 17. day period. Results: HPLC analysis showed a low abundance peak with chromatographic properties consistent with HbCS. Presence of this hemoglobin variant was confirmed by electrophoresis and gene sequencing. HbCS remained detectable by HPLC for 17. days after specimen collection, with minimal degradation. Conclusions: Our results suggest that HbCS is stable many days after blood collection. Consequently, it is not necessary to analyze specimens immediately after collection when assessing the potential presence of this hemoglobin variant. © 2015 The Canadian Society of Clinical Chemists.


Cembrowski G.S.,University of Alberta | Tran D.V.,University of Alberta | Higgins T.N.,DynaLIFEdx
Clinical Chemistry and Laboratory Medicine | Year: 2010

Background: Most estimates of biologic variation (sb) are based on periodically acquiring and storing specimens, followed by analysis within a single analytic run. We demonstrate for many intensive care unit (ICU) tests, only patient results need be statistically analyzed to provide reliable estimates of sb. Methods: Over 11 months, approximately 28,000 blood gas measurements (including electrolyte panels and glucose) were performed on one of two Radiometer ABL800 FLEX analyzers (Radiometer, Copenhagen, Denmark) from 1676 ICU patients. We tabulated the measurements of paired intra-patient blood samples drawn within 24 h of each other. After removal of outliers, we calculated the standard deviations of duplicates (SDD) of the intra-patient pairs grouped in 2-h intervals: 0-2 h, 2-4 h, 4-6 h, ... 20-22 h and 22-24 h. The SDDs were then regressed against the time intervals of 2-14 h; extrapolation to zero time represents the sum of sb and short-term analytic variation (sa). Results: Substitution of experimentally derived analytic error permitted the calculation of coefficient of variation (biologic) (CVb) (100 sb/mean): pH, 0.3%; pCO2, 5.7%; pO2, 13%; Na+, 0.6%; K+, 4.8%; Cl-, 0.8%; HCO3 -, 3.2%; iCa++, 2.4%; and glucose, 10.3%. The CVb of the electrolytes very closely matches the lowest estimates obtained in the usual manner. Conclusions: Derivation of the ratio of biologic to analytic variation indicates that the ABL800 is extremely suitable for ICU testing. This analysis should be extended to other point of care instrument systems. © 2010 by Walter de Gruyter Berlin New York 2010.


PubMed | DynaLIFEDx
Type: Case Reports | Journal: Clinical biochemistry | Year: 2012

Hemoglobinopathies and thalassemias together form the most common genetic disease in the world. Double heterozygosity, in which there is a hemoglobin variant, in both the - and non- globin chains, is very unusual. A novel double heterozygosity of the chain variant HbQ India with the non- chain HbD Punjab is described.The index case is a 39 year old female of Indian origin. HPLC analysis using the Bio Rad thalassemia method and electrophoresis at both alkaline and acid pH were performed.HPLC shows four major bands and electrophoresis at alkaline pH shows 3 bands and 2 bands at acid pH.Both the HPLC and electrophoresis at alkaline and acid pH are consistent for the double heterozygous hemoglobin variants HbQ India and HbD Punjab.This is the first literature report of the double heterozygosity of HbQ India/HbD Punjab.


PubMed | DynaLIFEDx
Type: Journal Article | Journal: Critical reviews in clinical laboratory sciences | Year: 2014

Celiac disease is a complex immune-mediated disorder that is triggered by ingestion of gluten and related proteins in genetically susceptible individuals. Under conditions of increased intestinal permeability, gluten-derived peptides can travel across the intestinal epithelium and undergo deamidation catalyzed by the tissue transglutaminase (TTG) enzyme. This renders them immunogenic in individuals expressing specific human leukocyte antigen (HLA) DQ heterodimers. The resulting immune response is characterized by the production of antibodies against both deamidated gliadin peptides (DGP) and TTG, generation of pro-inflammatory cytokines and activation of cytotoxic T cells. This response damages the intestinal epithelium resulting in the wide range of gastrointestinal and systemic symptoms observed in those with celiac disease. Celiac disease diagnosis has traditionally been based on biopsy and histological examination of the small intestine. While this approach is still considered the gold standard, it is invasive and susceptible to both false-positive and false-negative results. Several laboratory tests have become available to aid in the diagnosis and monitoring of celiac disease, and are the focus of this review. These include serological tests for celiac disease-specific antibodies such as anti-endomysial antibodies, anti-TTG antibodies and anti-DGP antibodies of both the immunoglobulin A (IgA) and immunoglobulin G (IgG) class, genetic tests to elucidate HLA DQ status and ancillary tests such as total IgA. While some have suggested that laboratory tests may replace intestinal biopsy in specific circumstances, others maintain that this procedure remains a critical component of celiac disease diagnosis. We review the analytical methodology, strengths, weaknesses, diagnostic performance and clinical utility of the various laboratory tests for celiac disease. Potential future markers and tests that are now considered obsolete are also discussed. Current clinical practice guidelines for the diagnosis and management of celiac disease from the European Society for Pediatric Gastroenterology, Hepatology and Nutrition, the American College of Gastroenterology and the World Gastroenterology Organisation are summarized, and important differences between these guidelines are highlighted.

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