Effective today, there will be changes to assays for Lyme Disease antibodies and Helicobacter pylori IgG antibodies.

For the Lyme Disease testing, we will continue offering options for acute disease (less than four weeks from onset of disease symptoms) or chronic disease. The change is to an assay for total Lyme antibodies that is available 7 days a week with 2 hour turnaround time upon receipt in laboratory. Testing detects infection caused by both European and North American strains of Borrelia.

Helicobacter IgG testing is changing to a mailout to reference laboratory. Orders for this testing have declined nationwide following recommendations by the American Gastroenterology Association and American College of Gastroenterology against routine use of this testing, with multiple assay vendors deciding to pull the assay from the US market.

Details on the tests are as follows:

Test Name	Epic #	Reflex if positive*	Reference range (antibody index)
LYME DISEASE AB - ACUTE DISEASE	LAB7769	Western blot IgG and IgM	Negative: <= 0.8 Equivocal: 0.9 – 1.0 Positive: >= 1.1
LYME DISEASE AB (LATE DISEASE)	LAB7770	Western blot IgG	Negative: <= 0.8 Equivocal: 0.9 – 1.0 Positive: >= 1.1
HELICOBACTER PYLORI ANTIBODIES, IGG	LAB8917	None	Per reference laboratory

*Reflex for positive or equivocal Lyme tests are referred to reference laboratory for Western blot analysis. For the acute panel, if either IgG or IgM screen is positive, there is automatic reflex to Western blot for IgG and IgM. The CDC does not recommend performing Lyme IgM Western Blot testing on patients with signs or symptoms of greater than 30 days' duration, rationalizing a different approach to confirmatory testing for acute and late disease. No testing is recommended for patients with erythema migrans.

Questions should be directed to Matthew Krasowski, MD, PhD, medical director of the Clinical Chemistry Laboratory (384-9380, matthew-krasowski@uiowa.edu).