Otolaryngology Coding Alert

Despite CPT's revision of 95027, intradermal dilutional testing (IDT), commonly called skin end point titration (SET) testing, remains a sticky matter. But some expert answers on what's new, current guidelines, and coverage should clear your head. 1. What Is IDT? Knowing what these tests are is crucial to understanding how to report them. Otolaryngologists use intracutaneous, sequential and incremental tests to determine the safe starting dose for immunotherapy. IDT allows the physician to determine the lowest dilution that will produce a positive skin reaction. To identify the low point, the physician conducts repeated tests with different dilutions of the treatment allergen or allergen mixture. The first test contains a weak dilution, followed by a second test that is stronger, says Michelle Lutke, administrator for Greenley Oaks ENT in Sonora, Calif. The doctor increases the strength of all subsequent tests by the given factor, such as 10, until he identifies the "end point" the point at which the negative result becomes positive. "Generally, it takes three tests (dilutions) per allergen to determine the endpoint," according to HGS Administrators (HGSA), Pennsylvania's Medicare Part B carrier. 2. What Does the New Wording Change? The IDT concept has been around for a while without any major changes. But CPT recently revised the procedural code used to report the testing. Before 2003, 95027 referred to "skin end point titration" only. With CPT 2003, the definition expanded to "intracutaneous (intradermal) tests, sequential and incremental, with allergenic extracts for airborne allergens, immediate type reaction, specify number of tests." To eliminate physician and payer confusion regarding coding requirements and coverage of SET, the AMA changed the code to more properly describe the technique as IDT. Although the new definition changed the wording considerably, the meaning remains the same. The new definition clarifies one important aspect. You must now specify the number of tests. "Before the definition change, insurance companies would rarely recognize the number of tests without a battle," Lutke says. The wording change more accurately reflects the way offices perform IDT. 3. Are the Tests Stick- or Antigen-Based? Although CPT now requires you to report the number of tests, the definition does not specify what you should base the quantity on. Without further guidance from CPT, you may wonder whether dilutions, pricks, scratches, injections or allergens unlock the magic number of SETtests to report. But the number of tests refers to the sticks used, according to the American Association of Otolaryngologic Allergy (AAOA).

"Each stick is a separate test that the physician reads and measures for reaction," Lutke says. Therefore, you should bill for each test/stick within each antigen.

To reflect the quantity of tests that the otolaryn-gologist performs, record the number of sticks in the unit [...]