Comparing G6PD Tests Using Capillary Blood Versus Venous Blood

Correlation of G6PD Activity Across Different Sample Sources, and Different G6PD Testing Platforms

In this study we propose to determine the correlation in glucose-6phosphate dehydrogenase enzyme activity in capillary blood obtained from a finger stick versus a venous blood specimen. As secondary endpoints we will seek to correlate phenotype as determined by quantitative and qualitative G6PD test, genotype as determined by PCR and DNA sequencing with flow cytometry. The secondary endpoints are critical for the design of G6PD diagnostic test evaluation studies.

Study Overview

• Status: Completed
• Conditions: Glucose-6 Phosphate Dehydrogenase Deficiency
• Intervention / Treatment: Other: G6PD Test

Detailed Description

In this study we propose to determine the correlation in glucose-6 phosphate dehydrogenase enzyme activity in capillary blood obtained from a finger stick versus a venous blood specimen. We will also compare results of different G6PD tests with known G6PD genetic profiles. The results of the study will inform design of future G6PD diagnostic development & evaluations. This research will be conducted in MaeSot Thailand, where G6PD deficiency has a high prevalence. Study participants will be recruited into three groups of 50 volunteers per group: 50 G6PD-deficient individuals, 50 G6PD-normal individuals, and 50 G6PD-intermediate individuals. Following a written informed consent, participants will donate about 3 ml of venous blood and about 4 drops of capillary blood (fingerstick). There will be no direct benefit to research participants.

• Study Type: Interventional
• Enrollment (Actual): 150
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Thailand
  • Mae Sot, Thailand
    • Shoklo Malaria Research Unit (SMRU)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Previous G6PD test at SMRU clinic
• Patient willing to participate and sign informed consent form
• Patient willing to allow donated sample to be used in future research
• Subjects 18 years of age or older

Exclusion Criteria:

• patients with severe malaria or other severe illness
• Patients who received a blood transfusion in the last 3 months
• Patients who received primaquine in the past 1 month (this is to ensure that previous characterization of phenotype in the healthy subject has not been influenced by a recent hemolytic reaction)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
No Intervention: G6PD Testing; All subjects receive G6PD test	Other: G6PD Test; All subjects are tested by multiple G6PD tests; Other Names: Trinity spectrophotometric assay; Flow cytometry; CareStart; Florescent Spot Test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Correlation of capillary and venous blood results using Trinity quantitative G6PD test	Comparison of the performance of the Trinity quantitative test using capillary blood, vs the performance of the same test using venous blood.	Six months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Concordance between a flow cytometry-based G6PD test and the spectrophotometric gold standard	Percent agreement between the quantitative results of the flow cytometry assay and the quantitative results of the spectrophotometric assay.	six months
Categorical accuracy of a flow cytometry-based G6PD test against the spectrophotometric gold standard and genotyping	Using a predefined cutoff to categorize values from each quantitative test, determine percent agreement within each category between the two tests.	six months
Concordance between a qualitative G6PD test and the spectrophotometric gold standard	Compare sensitivity & specificity of qualitative results of the G6PD test and the categorical results of the quantitative spectrophotometric assay.	Six months
Categorical accuracy of qualitative G6PD test against spectrophotometric gold standard	Percent agreement between the qualitative G6PD test and the categorical results of the spectrophotometric gold standard	six months
Association between flow cytometry-based test and sample genotype	Determine accuracy of phenotypic results of flow cytometry assay against genetic profile.	Six months

Collaborators and Investigators

• Sponsor: PATH
• Collaborators: University of Oxford; Mahidol University
• Investigators: Principal Investigator: Francois Nosten, MD/PhD, Shoklo Malaria Research Unit, Mahidol Oxford Research unit; Study Chair: Gonzalo Domingo, PhD, PATH; Study Chair: Germana Bancone, PhD, Shoklo Malaria Research Unit, Mahidol Oxford Research unit; Study Chair: Sarah McGray, MPH, PATH

Study record dates

Study Major Dates

• Study Start: February 1, 2014
• Primary Completion (Actual): July 1, 2014
• Study Completion (Actual): December 1, 2014

Study Registration Dates

• First Submitted: February 14, 2014
• First Submitted That Met QC Criteria: February 19, 2014
• First Posted (Estimate): February 24, 2014

Study Record Updates

• Last Update Posted (Estimate): August 19, 2015
• Last Update Submitted That Met QC Criteria: August 18, 2015
• Last Verified: February 1, 2014

More Information

Terms related to this study

• Keywords: venous; Glucose-6 phosphate dehydrogenase deficiency; capillary; genotype phenotype correlation
• Additional Relevant MeSH Terms: Metabolic Diseases; Hematologic Diseases; Genetic Diseases, Inborn; Anemia; Carbohydrate Metabolism, Inborn Errors; Metabolism, Inborn Errors; Anemia, Hemolytic, Congenital; Anemia, Hemolytic; Glucosephosphate Dehydrogenase Deficiency
• Other Study ID Numbers: SMRU 1302