ICD 10 Coding Alert

Question: Our pediatrician recently saw an infant that presented with a severe case of diaper rash. She ordered a strep test, which came back positive, so the pediatrician diagnosed the patient with perianal strep infection. The provider chose A49.1 in the patient’s electronic medical record (EMR), 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?

Maine Subscriber

Answer: While we would strongly encourage you to discuss the rationale behind this diagnosis with your provider, A49.1 (Streptococcal infection, unspecified site) does, for the reason you suggest, seem 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.