Pathology/Lab Coding Alert

Update therapeutic drug assay coding for RA patients.

With four additional CPT^® 2022 codes for unique analyte testing, your lab has four fewer reasons to deal with documentation and billing hassles associated with nonspecific codes.

Get familiar with the following new and revised codes, and learn how they might impact your lab coding this year:

• 80220 (Hydroxychloroquine)
• 82656 (Elastase, pancreatic (EL-1), fecal, qualitative or semi-quantitative; qualitative or semi-quantitative)
• 82653 (… quantitative)
• 83521 (Immunoglobulin light chains (ie, kappa, lambda), free, each)
• 83529 (Interleukin-6 (IL-6))

Add Hydroxychloroquine Therapeutic Drug Assay Analyte Code

Say goodbye to using 80299 (Quantitation of therapeutic drug, not elsewhere specified) when your lab performs a therapeutic drug assay for hydroxychloroquine. With the CPT^® 2022 code addition, you should now be reporting 80220 for the test.

This is a quantitative test that physicians may order to evaluate the therapeutic dose of hydroxychloroquine medication in the patient specimen. “Labs typically perform this analysis using an instrumented method such as liquid chromatography-tandem mass spectrometry (LC-MS/MS),” says William Dettwyler, MT-AMT, president of Codus Medicus, a laboratory coding consulting firm in Salem, Oregon.

Use: Originally used to prevent or treat malaria, clinicians may commonly prescribe hydroxychloroquine for patients with autoimmune conditions such as rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE).

EUA revoked: The Food and Drug Administration (FDA) initially granted emergency use authorization (EUA) for hydroxychloroquine to treat COVID-19 in certain hospitalized patients, but the agency revoked the EUA on June 15, 2020, and issued a summary report outlining serious heart rhythm problems and other safety issues surrounding the use of the drug in COVID-19 patients.

Medical necessity: Look for the ordering clinician to cite the medical reason for the test as an ICD-10-CM code or a narrative diagnosis that you can link to a diagnosis code. Medicare rules indicate coverage for conditions such as RA and SLE and for testing associated with retinopathy, which is a potential side effect of hydroxychloroquine treatment.

Check Out These Chemistry Section Changes

When you report chemistry tests for interleukin-6 (IL-6), immunoglobulin light chains such as kappa or lambda, or quantitative elastase, you now have specific codes to report the service.

Lab methods for these tests commonly involve immunoassay, so you may have been reporting these tests with a nonspecific chemistry code such as 83520 (Immunoassay for analyte other than infectious agent antibody or infectious agent antigen; quantitative, not otherwise specified).

Pancreatic elastase: In addition to new code 82653 for quantitative fecal pancreatic elastase (EL-1), CPT^® 2022 revises 82656 for qualitative or semi-quantitative EL-1, making it a parent code for new code 82653.

EL-1 is an enzyme produced by the pancreas that helps break down proteins, fats and carbohydrates during digestion. Because EL-1 is secreted in feces, the fecal EL-1 test can help evaluate pancreatic insufficiency, which may be involved in conditions such as diabetes, cystic fibrosis (CF), inflammatory bowel disease (IBD), or pancreatic inflammation or tumors.

“Having separate codes to distinguish whether the test is quantitative or qualitative/ semi-quantitative will be helpful for labs to accurately report their work,” Dettwyler says.

Immunoglobulin light chain: Clinicians may order tests for free kappa and lambda in a serum specimen to aid in diagnosis or treatment monitoring for plasma-cell disorders such as multiple myeloma (MM) and amyloidosis (AL). You can now turn to 83521 for the tests instead of an unlisted code such as 83520.

An abnormal level of free (unbound) serum light chain proteins such as kappa and lambda may indicate an overabundance or deficit of plasma cells that produce the proteins. These proteins combine with heavy light chains to form antibodies.

Physicians typically order both free kappa and free lambda and use the ratio of the two light chains for diagnostic purposes. “Two assays are necessary to separately quantify kappa and lambda free light chains and generate that ratio, and that’s why the new code references ‘each,’” according to David Parker, PhD, from Precision for Medicine, representing The Binding Site at the annual Clinical Laboratory Fee Schedule public meeting (presentation available at https://downloads.cms.gov/media/audio/gmt20210624-130002_clfs-annua_1920x1080.mp4 )

Do this: Report 83521 x 2 when your lab tests for kappa and lambda.

IL-6: Physicians may order an interleukin-6 test to help evaluate inflammation in a number of clinical situations, and CPT^® 2022 provides 83529 to describe the procedure.

IL-6 is a cytokine (small protein) involved in the body’s immune response and may be elevated in cardiovascular disease, some autoimmune disorders such as RA, and some infections. IL-6 testing has proved beneficial in identifying severe inflammation in COVID-19 patients to help clinicians evaluate risks associated with ventilator use.