ED Coding and Reimbursement Alert

Question: We recently saw a toddler in the ED who presented with a severe case of diaper rash. We ordered a strep test, which came back positive, so the provider diagnosed the patient with perianal strep infection. The ED physician chose A49.1 in the patient’s electronic medical record, but I don’t think that’s the correct code as the specific site of the infection, the patient’s anal area, is known. So, my question is this: What is the correct way to code this?

Oregon Subscriber

Answer: Since you know the site of the strep, A49.1 (Streptococcal infection, unspecified site) does appear to be the wrong choice. The Excludes1 note that accompanies all the ICD-10 Chapter 1 (A00-B99) codes seems to back up your opinion as it states that these codes exclude “certain localized infections — see body system-related chapters.”

The note points you in the direction of using a code from the Diseases of the Skin and Subcutaneous Tissue Chapter, where you will find L22 (Diaper dermatitis). This code would be a more appropriate choice, as it locates the skin as the site of the infection.

You can then add a code from the B95.- (Streptococcus, Staphylococcus, and Enterococcus as the cause of diseases classified elsewhere) group to pinpoint the cause of the infection. The most likely code would be B95.0 (Streptococcus, group A …), as group A beta-hemolytic streptococci are the usual cause of perianal streptococcal dermatitis (Source: www.aafp.org/afp/2000/0115/p391.html). However, test results may indicate otherwise, so you could possibly use another code, such as B95.5 (Unspecified streptococcus …), if the strain remains unknown.