Neurology & Pain Management Coding Alert

Neurology & Pain Management Coding:

Remember Secondary Dx for These Huntington’s Patients

Question: A patient reports to the neurologist with a diagnosis of Huntington’s disease. Encounter notes indicate another diagnosis of dementia with anxiety. What is Huntington’s disease, and how many ICD-10-CM codes should I report for this patient?

Connecticut Subscriber

Answer: You’ll report a pair of diagnosis codes for this patient. First, use G10 (Huntington’s disease) to represent the patient’s Huntington’s disease. If the physician referred to the condition as Huntington’s chorea or Huntington’s dementia, you’d also use G10.

To represent the patient’s dementia with anxiety, you’ll choose one of the following codes, depending on encounter specifics:

  • F02.84 (Dementia in other diseases classified elsewhere, unspecified severity, with anxiety)
  • F02.A4 (Dementia in other diseases classified elsewhere, mild, with anxiety)
  • F02.B4 (Dementia in other diseases classified elsewhere, moderate, with anxiety)
  • F02.C4 (Dementia in other diseases classified elsewhere, severe, with anxiety)

In addition to dementia with anxiety, there are other disorders you should report along with G10 if the notes indicate that the patient suffers from them. In the notes beneath G10, ICD-10-CM instructs you to “Use additional code, if applicable, to identify:

  • “Dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-)
  • “Dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3)
  • “Dementia with psychotic disturbance (F02.82, F02.A2, F02.B2, F02.C2)
  • “Dementia without behavioral disturbance (F02.80, F02.A0, F02.B0, F02.C0)
  • “Mild neurocognitive disorder due to known physiological condition (F06.7-)”

More on Huntington’s: According to Mayo Clinic, “Huntington's disease causes nerve cells in the brain to decay over time. The disease affects a person’s movements, thinking ability and mental health.”

Chris Boucher, MS, CPC, Senior Development Editor, AAPC