Primary Care Coding Alert

Question: A patient presented with an itchy, blistered rash on her skin, which she believed was caused by contact with a dog who had fleas. The provider’s exam notes indicated erythematous papules based on observation and a palpitation of the area. Should I code this with the ICD-10 signs and symptoms code for a rash?

Illinois Subscriber

Answer: The provider may render a diagnosis at any time on the basis of the exam. If that diagnosis appears in the note, then you should report it and not the signs or symptoms the patient presents with unless those signs and symptoms, per ICD-10 guideline 1.A.18.b, are not “routinely associated with that diagnosis.”

In this case, the provider has documented erythematous papules on the patient’s skin, which is far more specific than a rash. Additionally, the rash would be an associated symptom of the erythema, which by definition describes the redness associated with a rash.

Based on this analysis, your best bet would be to code L53.8 (Other specified erythematous conditions) for the diagnosis rather than reporting a more general sign and symptom code such as R21 (Rash and other nonspecific skin eruption) for this encounter.