Radiology Coding Alert

Question: The physician saw an HIV-positive patient for treatment of numerous chronic mouth ulcers. What's the rule on coding the condition before or after the HIV diagnosis? Also, should I code the patient as asymptomatic HIV status?

Indiana Subscriber

Answer: There's two important questions at play here. The first addresses the proper sequencing of the diagnosis codes for mouth ulcers and human immunodeficiency virus- (HIV) positive status. The second relates to addressing whether or not you should consider the mouth ulcers as a related condition to the patients' HIV-positive status. The ICD-10-CM guidelines state:

"If a patient with HIV disease is admitted for an unrelated condition (such as a traumatic injury), the code for the unrelated condition (e.g., the nature of injury code) should be the principal diagnosis. Other diagnoses would be B20 followed by additional diagnosis codes for all reported HIV-related conditions."

Based on these guidelines, the question then becomes - are the mouth ulcers a result of the patient's HIV status? According to one peer-reviewed study in the Canadian Journal of Infectious Diseases, "Patients with human immunodeficiency virus (HIV) infection often suffer from persistent, painful ulcers that commonly occur on the soft palate, buccal mucosa, tonsillar area or tongue, which are referred to as aphthous ulcers." In addition to ulcers, numerous oral manifestations are common results of an HIV-positive compromised immune system.

While this description seems to justify coding the ulcers as a related condition, you ultimately should leave this designation up to the discretion of the provider. The provider's distinction here is important - as it will determine both the sequencing of the codes and the correct code to submit for HIV-positive status. If the provider decides that the conditions are interlinked, then you will code as B20 (Human immunodeficiency virus [HIV] disease) followed by K12.0 (Recurrent oral aphthae). If the provider determines that the diagnoses are not associated, then you will code as K12.0 followed by Z21 (Asymptomatic human immunodeficiency virus [HIV] infection status).