ICD 10 Coding Alert

Hint: Secondary Parkinsonism is different than Parkinson’s disease.

Coding Parkinson’s disease can be tricky because you need to select the correct ICD-10 code, be familiar with which CPT® codes are necessary, and correctly navigate the difference between Parkinson’s disease and secondary Parkinsonism.

Use these questions and answers to bolster your knowledge on coding Parkinson’s disease and secondary Parkinson’s disease correctly.

Define Parkinson’s for Clarity

Question 1: What is Parkinson’s disease?

Answer 1: Parkinson’s disease is a progressive disease of the nervous system. It primarily affects middle-aged and elderly people, and scientists believe it is associated with degeneration of the basal ganglia of the brain and a deficiency of the neurotransmitter dopamine.

Patients with Parkinson’s disease exhibit tremors in the extremities, jaw, and face, stiffness of the trunk, arms, and legs, swinging of arms during walking, and poor posture and balance. They move slowly, their speech and writing changes, they smile less, and they may have difficulty chewing, swallowing, and sleeping. They may become depressed and have mood changes.

Utilize These ICD-10 Codes for Parkinson’s Disease

Question 2: What ICD-10 code should I report for Parkinson’s disease?

Answer 2: You should report G20 (Parkinson’s disease) for Parkinson’s disease.

Other included diagnoses under G20 include the following:

• Hemiparkinsonism
• Idiopathic Parkinsonism or Parkinson’s disease
• Paralysis agitans
• Parkinsonism or Parkinson’s disease NOS
• Primary Parkinsonism or Parkinson’s disease.

Important: Code G20 has an Excludes1 note for G31.83 (Dementia with Parkinsonism), so report G31.83 if the surgeon documents dementia and Parkinsonism.

Distinguish Parkinson’s Disease from Secondary Parkinsonism

Question 3: What causes secondary Parkinsonism, and what ICD-10 codes should I report for secondary Parkinsonism?

Answer 3: Secondary Parkinsonism is similar to Parkinson’s disease; however, the symptoms are caused by certain medicines, a different nervous system disorder, or another illness.

You will turn to the following codes for secondary Parkinsonism:

• G21.0 (Malignant neuroleptic syndrome)
• G21.11 (Neuroleptic induced parkinsonism)
• G21.19 (Other drug induced secondary parkinsonism).
  Note: This diagnosis also includes other medication-induced Parkinsonism.
• G21.2 (Secondary parkinsonism due to other external agents)
• G21.3 (Postencephalitic parkinsonism)
• G21.8 (Other secondary parkinsonism)
• G21.9 (Secondary parkinsonism, unspecified).

Don’t miss: Each code for secondary Parkinsonism excludes dementia with Parkinsonism (G31.83), Huntington’s disease (G10), Shy-Drager syndrome (G90.3), and syphilitic Parkinsonism (A52.19).

Important: Since several of the secondary Parkinson’s ICD-10 codes direct you to report an additional code for adverse effects or to first code the drug or external agent causing the secondary Parkinsonism, you will want to make sure you carefully read all of the notes associated with these codes.