General Surgery Coding Alert

Question: One of our surgeons treated a patient with an abscessed wound on his left ankle by debriding the site and ordering a culture to identify any possible infectious organism. The area treated was about 12 sq cm and the debridement was “superficial,” according to the op note. The lab reported that the infecting organism was Staphylococcus aureus. How should we code the case?

Arkansas Subscriber

Answer: The correct code for the procedure is 11042 (Debridement, subcutaneous tissue [includes epidermis and dermis, if performed]; first 20 sq cm or less). You have to distinguish this code from 11043 (Debridement, muscle and/or fascia [includes epidermis, dermis, and subcutaneous tissue, if performed]; first 20 sq cm or less) based on the depth of the debridement. Also, you have to know the treated surface area to code this case correctly.

“Be very specific about how deep [the provider] went and the square centimeters of the debridement,” advises Maggie M. Mac, CPC, CEMC, CHC, CMM, ICCE, president of Maggie Mac-Medical Practice Consulting in Clearwater, Fla. If the surgeon doesn’t detail this in the note, make certain you ask for an addendum to the note to substantiate the appropriate service to bill.

Diagnosis: You should report the patient’s condition as L02.416 (Cutaneous abscess of left lower limb). You’ll notice that ICD-10 has a text note following category L02 that directs you to “Use additional code to identify organism (B95-B96).”

In this case, you should report B95.61 (Methicillin susceptible Staphylococcus aureus infection as the cause of diseases classified elsewhere). Although you don’t indicate that the lab identified this organism as “methicillin susceptible,” code B95.61 includes “Staphylococcus aureus infection NOS as the cause of diseases classified elsewhere.” Because this S. aureus infection is “Not Otherwise Specified” (NOS) regarding drug resistance, B95.61 is the best code choice.