Keeping track of all the different potential allergens that may be causing a patient’s skin rash is challenging enough. But when you add the complexity of different kinds of dermatitis tests that a dermatologist can perform, it’s enough to cause a coder to break out in a rash herself. The variety and complexity of allergy tests can certainly lead to coding mishaps — but understanding the codes and having clear documentation can help clear things up.

The tests that dermatologists commonly perform to learn the source of a patient’s allergic dermatitis include scratch tests and patch tests. Knowing what code to use means understanding what each test does, and how.

Count Each Allergen in Scratch Tests

Procedure: Percutaneous tests

AKA: Scratch tests, prick tests, puncture tests, Multi-Test

Codes: 95004 (Percutaneous tests [scratch, puncture, prick] with allergenic extracts, immediate type reaction, including test interpretation and report by a physician, specify number of tests) and 95010 (Percutaneous tests [scratch, puncture, prick] sequential and incremental, with drugs, biologicals or venoms, immediate type reaction, including test interpretation and report by a physician, specify number of tests).

In these tests, the dermatologist applies test solutions of possible allergens to scratches or shallow punctures of the skin. The code you report will depend on the type of solutions applied — allergenic extracts, such as dust, cat dander, and molds (95004), or antibiotics, biologicals, stinging insects, and local anesthetic agents (95010).

Dermatologists usually want to test several substances at once (often in blocks of eight), and each substance counts as a separate test, notes Pamela Biffle, CPC, CPC-P, CPC-I, CCSP, CHCC, CHCO, owner of PB Healthcare Consulting and Education Inc. in Watauga, Texas. Be sure to code for each allergen administered by putting the number in the “units” field of your claim form.

Hidden trap: Code...