Internal Medicine Coding Alert

Plus: Count every test to get the money your physician is due.

When your internist conducts a patch test and follow-up for a patient, don't let some of the calculations slip past your notice. Count each patch and any extra E/M services to round out a complete claim.

Include Office Visit Code

A new patient comes with a red, itchy rash on his arm. The internist makes an initial diagnosis of non-specified contact dermatitis (692.9, Contact dermatitis and other eczema; unspecified cause). The physician then applies patch tests and asks the patient to return in 48, 72, and 96 hours for readings.

Code it: Because your physician applied the patch test, you'll report 95044 (Patch or application test[s] [specify number of tests]). You'll also bill for any E/M service the internist provided for the patient. Because you're filing a claim for a new patient, select the appropriate E/M code from 99201- 99205 (Office or other outpatient visit for the evaluation and management of a new patient ...).

Modify it: Append modifier 25 (Significant, separately identifiable evaluation and management service by the same physician on the same day of the procedure or other service) to your E/M code to notify the payer that the physician performed an initial evaluation that led her to complete patch testing on the patient. You can only consider reporting modifier 25 when coding an E/M service, Janet Palazzo, CPC, a coder in Cherry Hill, N.J., says.

Count Every Unit

When conducting a patch test, the physician applies several patches on the patient to test for his reaction to various allergens. Payers consider each test as an individual procedure, so you should calculate accordingly when billing.

Tip: Bill your units in block 24G of the CMS-1500 form according to the number of allergens tested, says Lori Lemond, CPC, coding supervisor for Arizona Medical Clinic in Peoria, Ariz. Educate staff to double check the number of units on the charge ticket, and educate your physician to document the correct units. Front-desk staff can also help by asking the internist how many patch tests she administered.

Report Multiple E/M for Follow-Up

Just as you report 95044 for each patch test applied, you'll submit an E/M code for each patch test checked.

Because the physician is now seeing an established patient, select your E/M code from 99211-99215 (Office or other outpatient visit for the evaluation and management of an established patient ...).

Exception: If a nurse or physician assistant reads the patch tests, steer clear of higher-level E/M codes. Report 99211 as long as the physician is on-site when the staff member reads the results.

The physician should be able to make a more definitive diagnosis once she reads the patch test results. Possibilities could include:

• 692.4 -- Contact dermatitis and other eczema; due to other chemical products
• 692.81 -- ... due to cosmetics
• 692.0 -- ... due to detergents
• 692.3 -- ... due to drugs and medicines in contact with skin
• 692.89 -- ... other.