The Streck HbA1c-Cellular® Control: Intact Red Blood Cells for Hemoglobin A1c Testing

Wednesday, May 8, 2013

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Please see our Clinical Diagnostics section to find manufacturers that sell these products

Diabetes is a chronic disease resulting from lack of insulin (type 1 diabetes mellitus [DM]), or the combination of insulin resistance, insufficient insulin, and abnormal glucagon secretion (type 2 DM). Of the patients with DM, only 5% to 10% have type 1; the remaining 90% to 95% have type 2 DM. The complications of untreated and poorly controlled diabetes ultimately lead to kidney disease, peripheral and cardiovascular disease, and neuropathy. Unfortunately, the rates of diabetes and prediabetes continue to increase in the United States. The Centers for Disease Control and Prevention estimated that in 2011 nearly 26 million people aged 20 years or older in the United States had diabetes, and 79 million had prediabetes.1

Blood Glucose Control Plus the Diagnosis of DM

As the red blood cells circulate, the hemoglobin within the cells becomes bound to glucose from the plasma. This nonenzymatic process occurs over the lifetime of the cell, a mean of 120 days. Because the measurement of glycated hemoglobin A (HbA1c) reflects plasma glucose levels over the previous 2–3 months, HbA1c testing has emerged as the best way to monitor how well a patient’s DM is being controlled. With standardization of the assay, the 2009 International Expert Committee Report on the Role of the HbA1c Assay in the Diagnosis of Diabetes and the American Diabetic Association have affirmed that HbA1c testing can also be used for the diagnosis of DM.2,3

HbA1c analyzers are available in several formats, each of which rely on one of several testing methods, including HPLC, immunoassay and boronate-affinity-based methodologies, or, for point-of-care devices, chromatography. Calibration and QCs are required for HbA1c testing. If samples of known concentrations (the QCs) produce the expected results, then the patient’s results are validated. The best QC materials are those that are “patient-like.” In HbA1c testing, which requires whole blood samples, the most patient-like materials include intact blood cells.

Streck, Inc. (Omaha, NE) offers the CE-marked* HbA1c-Cellular®, which the company claims is the first HbA1c control available with intact red blood cells. The control checks the entire HbA1c procedure, including the step of lysing the red blood cells. The product is a ready-to-use liquid control with an open-vial stability of 30 days and a closed-vial stability of 180 days when refrigerated. The HbA1c-Cellular is appropriate for immunoassay and ionic exchange HPLC methodologies. A free quality control program is included.

The HbA1c-Cellular control is appropriate for several immunoassay and HPLC systems, including:

  • ARCHITECT® c Systems (Abbott, Abbott Park, IL)
  • ADAMS™ A1c HA-8160 (A. Menarini Diagnostics, Barcelona, Spain)
  • UniCel® DxC 600/800 (Beckman Coulter®, Fullerton, CA)
  • D-10/Variant II™/Variant II™ Turbo (Bio-Rad®, Hercules, CA)
  • Dimension® Series (Siemens, Erlangen, Germany)
  • VITROS® 5,1 FS/5600 (Ortho Clinical Diagnostics, Rochester, NY)
  • cobas INTEGRA®/6000/c 311 (Roche Diagnostics, Mannheim, Germany)
  • Tosoh G7/G8/A1c 2.2 Plus (Tosoh Bioscience, Tokyo, Japan).

Streck also offers the A1c-Cellular in cap-pierceable vials. This configuration allows automatic sampling for HbA1c analyzers with these capabilities and offers a number of advantages over other controls on the market:

  • Pierceable cap allows closed-vial testing
  • One lot of controls for up to 6 months of testing
  • Plastic vials for increased employee safety
  • No sample cups or external dilution for some systems.

Another Streck product is the A1c-Cellular Linearity, which the company says is the only commercially available HbA1c linearity/calibration verification material with intact red blood cells. The A1c-Cellular Linearity allows for assessment of the accuracy and linear reportable range of the HbA1c parameter. It tests the entire HbA1c procedure, including red blood cell lysis.

The assay includes instrument-specific target values and expected ranges for immediate results. It can be used for:

  • ARCHITECT c Systems (Abbott)
  • UniCel DxC 600/800 (Beckman Coulter)
  • D-10/Variant II/Variant II Turbo (Bio-Rad)
  • Dimension Series (Siemens)
  • VITROS 5,1 FS/5600 (Ortho Clinical Diagnostics)
  • cobas INTEGRA/6000 (Roche Diagnostics)
  • Tosoh G7/G8 (Tosoh Bioscience).

The A1c-Cellular Linearity is available in a five-level set with plastic cap-pierceable vials. Data can be submitted to Streck for a linearity report at no additional charge.

*The HbA1c-Cellular is also licensed for sale in Canada.

References

  1. U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 2011. National diabetes fact sheet: national estimates and general information on diabetes and prediabetes in the United States, 2011. Available at http://www.cdc.gov/diabetes/pubs/pdf/ndfs_2011.pdf. Accessed May 4, 2013.
  2. International Expert Committee. International Expert Committee report on the role of the A1C assay in the diagnosis of diabetes. Diabetes Care2009, 32, 1327–34.
  3. American Diabetes Association. Diagnosis and classification of diabetes mellitus. Diabetes Care2010, 33 (Suppl 1), S62–9.

Please see our Clinical Diagnostics section to find manufacturers that sell these products