Immunochemistry, Main lab, Test Utilization

Cyclic Citrullinated Peptide Antibody IgG

On June 27th 2017, Spectrum Health Regional Laboratory (SHRL) will be switching instrument/vendors that perform the Cyclic Citrullinated Peptide Antibody (anti-CCP) IgG assay.  We will be switching from the INOVA platform to the PHADIA-250 platform.

Method comparison studies showed that the results compare very well in terms of interpretation (NEGATIVE, EQUIVOCAL or POSITIVE); however, the numerical results do not compare due to assay differences. In fact the “U” reported by the INOVA (former) method was not U/mL but a dimensionless measure specific to that assay and not convertible to U/mL

NEW REFERENCE RANGE

Cyclic Citrullinated Peptide (CCP)
Antibody IgG
NEW REFERENCE RANGE
U/mL
Former Reference Range
U
NEGATIVE <7 <20
EQUIVOCAL 7-10
Recommended to retest
after 8-12 weeks
20-39
POSITIVE >10 40-59,
(strong >=60)

As with all laboratory testing, no tests should be ordered without consideration of the clinical history and presentation. In terms of Anti-CCP or Rheumatoid Factor (RF), clinical concerns of rheumatoid arthritis (RA) should drive the use of both Anti-CCP and RF tests.  Reported sensitivities for RA in both tests have been reported between 58 to 67% with specificity of antiCCP approximately 96% and RF 85%.  Of interest, over a 13 month period from February 2016 through February 2017, there were 3476 anti-CCP orders representing 3392 patients with only 239 reported as positive.

Questions, comments and inquiries about this test, or any other lab test, may be directed to Dr. David Alter using the “contact us” link above.

TEST INFORMATION

Cyclic Citrullinated Peptide Antibody IgG – SH code #7175, Epic Code #LAB, CPT Code #86200

Previous Post Next Post

You Might Also Like

No Comments

Leave a Reply

one × 5 =