Browsing Tag


Microbiology, Test Utilization

Clostridium difficile Two-Step Algorithm Testing

Spectrum Health Regional Laboratory is preparing to switch Clostridium difficile testing methods from solely using a molecular approach to a 2-step algorithm utilizing an Enzyme Immunoassay (EIA) that detects two C. difficile-specific proteins (glutamate dehydrogenase or GDH, and A/B toxin) with indeterminant EIA specimens reflexed to PCR (see flowchart below). It is estimated that approximately 90% of patients tested will be resolved by EIA and not require reflexive PCR testing. This algorithm decreases expenses to the patient by an average of 65% as compared to current testing without sacrificing result quality. Specimens will be batched for EIA testing at a frequency to ensure that results are available within 6 hours of receipt by the laboratory so that proper contact isolation precautions may be initiated when indicated. Continue Reading

Microbiology, Test Utilization

Enteric Pathogens by PCR replacing Stool Culture Orderable

Effective August 18, 2016, the Spectrum Health Regional Laboratory Microbiology Department will begin offering the Verigene® Enteric Pathogens Test, a new rapid molecular test that simultaneously detects and identifies the following pathogenic enteric bacteria, viruses, and toxins that commonly cause acute community-acquired diarrhea. Testing occurs directly from stool in Cary-Blair preservative with a 1 day turnaround time (2-3 days faster than current methods). Continue Reading

Advanced Technology Laboratory, Chemistry, Molecular Diagnostics

Hepatitis C Antibody Reporting Change

The Spectrum Health Laboratory is now reporting all Hepatitis C Antibody results as Negative or Positive only. (Hepatitis C Antibody, Screening; Hepatitis C Antibody, Diagnostic) The separate Low Positive result category has been eliminated.

The Laboratory has changed to a new Hepatitis C Antibody reagent which no longer includes the Low Positive result category in its product labeling (the FDA approved instructions which laboratories are required to follow). The Low Positive category was defined on the basis of old guidelines which indicated that results above a defined S/CO (signal/cutoff) value were considered to have a 95% or greater probability of being true positives and did not require RIBA confirmation. The RIBA confirmatory test has not been available for several years now. Current guidelines are that all positive Hepatitis C Antibody tests should be confirmed with a HCV RNA test. The Spectrum Health laboratory reflexes all positive antibody results to this test. A positive HCV RNA following a positive antibody result should be considered indicative of active HCV infection, and may be used as a baseline for antiviral therapy.

Any questions concerning this change in Hepatitis C Antibody reporting may be directed to Dr. Richard Horvitz in the Pathology department.

Immunochemistry, Test Utilization

Helicobacter Antibody Testing

Effective March 1, 2016, Mayo Medical Laboratories will no longer perform any Helicobacter Antibody (IgG, IgM, or IgA) testing. The Mayo Clinic has determined that Helicobacter antibody testing has a poor predictive value, and also has poor clinical sensitivity and specificity. While a negative antibody result suggests the absence of prior Helicobacter exposure, a positive result is not predictive of active Helicobacter infection. Furthermore, since antibody levels may remain positive for years following resolution of infection serologic testing cannot be used to distinguish active from past infection or document eradication of Helicobacter infection following treatment. See the full text of a recent Mayo Medical Laboratories Communique article on Helicobacter testing methods for further information on the various available tests for Helicobacter infection.

Effective as of the above date, the Helicobacter pylori Antibody IgM and Helicobacter pylori Antibody IgA tests will no longer be available through the Spectrum Health Laboratory. The Helicobacter pylori Antibody IgG test (#8596), which is performed in house, will continue to be available until further notice, but may be subject to further review at a later time. Some third party payers are now considering Helicobacter antibody tests to be medically unnecessary and no longer reimbursing for them.

The Helicobacter pylori breath test (#3013, available from the Spectrum Health Laboratory) and the Helicobacter pylori Antigen, Stool test (#4307, available as a send out to Mayo Medical Laboratories) are now considered the primary recommended tests for the diagnostic evaluation of suspected Helicobacter infection. Refer to the linked Mayo diagnostic algorithm for further information on recommended approaches to Helicobacter pylori diagnostic testing.

Any questions concerning these changes in Helicobacter pylori testing may be directed to Dr. Richard Horvitz in the Pathology Department.