Pathology/Lab Coding Alert

See what you can expect for payment, too.

When physicians order quantitative assays for therapeutic drug monitoring purposes, you’ll have some brand new codes to use beginning Jan. 1, 2014.

Read on to make sure your lab is ready to start using analyte-specific codes when the new year rolls around, in place of the more generic codes you’ve been using.

Know When to Use Therapeutic Drug Assay Codes

Not every drug test justifies reporting a code from the “therapeutic drug assays” CPT® section. You should reserve these codes for quantitative testing and turn instead to “drug testing” codes 80100-80104 for qualitative screening, according to Robin Miller Zweifel, MT (ASCP), a laboratory coding and billing compliance consultant in Niota, Tenn.

Physicians often order therapeutic drug assays to evaluate patients taking medications. The assays aid the physician in evaluating clinical scenarios, such as:

• Possible toxic concentration
• Subtherapeutic concentration resulting in lack of treatment response
• Change in patient’s clinical state
• Blood concentration change following dosage modification
• Patient compliance with medication regimen
• Potential drug interaction with co-medications

Learn the New Codes

CPT® 2014 introduces the following 10 codes in the therapeutic drug assay section:

• 80155 — Caffeine
  
• Physicians may prescribe this medication to treat apnea in premature infants
  
• 80159 — Clozapine
  
• This is an antipsychotic medication that physicians often monitor for patient compliance
  
• 80169 — Everolimus
  
• An immunosuppressant drug, physicians may order quantitative testing to evaluate organ rejection or infection
  
• 80171 — Gabapentin
  
• Physicians may monitor for therapeutic levels of this antiepileptic drug
  
• 80175 — Lamotrigine
  
• This is an anticonvulsant used in epilepsy and bipolar disorder that requires testing for therapeutic target levels
  
• 80177 — Levetiracetam
  
• Physicians may monitor serum concentration for anticonvulsant, especially patients with renal disease
  
• 80180 — Mycophenolate (mycophenolic acid)
  
• This test helps monitor immunosuppression in organ transplant patients
  
• 80183 — Oxcarbazepine
  
• Physicians may order this test to observe serum concentration for seizure control
  
• 80199 — Tiagabine
  
• Testing measures serum levels as adjunctive therapy for seizures
  
• 80203 — Zonisamide

Physicians may monitor serum levels as adjunctive therapy for seizures.

Check the Pricing Proposal

After receiving input from industry stakeholders at the annual Clinical Laboratory Fee Schedule (CLFS) public meeting earlier this year, CMS determined the basis of payment and posted the recommendations online, as explained by CMS meeting coordinator Glenn McGuirk.

Study the following table to see the CMS-recommended crosswalks and the current payment rate for those codes.

*National limit amount

The CMS payment recommendations for these new codes represent the view point of several presenters at the annual CMS meeting. For instance, specific crosswalks were recommended for the 10 new codes “based on existing drug codes that have similar analytical methods and clinical uses,” said Greg Root, speaking on behalf of the American Association for Clinical Chemistry.

Other commentators had urged CMS to use two methodology codes for the payment basis, as follows, depending on the new code test method:

• 82491 — Chromatography, quantitative, column (e.g., gas liquid or HPLC); single analyte not elsewhere specified, single stationary and mobile phase
  
• 82542 — Column chromatography/mass spectrometry (e.g., GC/MS, or HPLC/MS), analyte not elsewhere specified; quantitative, single stationary and mobile phase.
  

CMS followed this recommendation for 80199, but opted for similar drug codes rather than method codes for all other CPT® 2014 therapeutic drug assay code additions.

Update billing codes: For the 10 new anaylte-specific tests, most labs would currently report 80299 (Quantitation of drug, not elsewhere specified). Don’t forget to shift to the new, more specific codes when they go into effect on Jan. 1.