MDS Alert

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

Coding Parkinson’s disease can be difficult because you must follow all of the coding notes in ICD-10 and understand the difference between Parkinson’s disease and secondary Parkinsonism. Parkinson’s disease, when coded correctly, should fall into the acute neurologic clinical category.

Check out these questions to bolster your knowledge about Parkinson’s disease.

First, 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. Scientists believe it is associated with degeneration of the basal ganglia of the brain and a deficiency of the neurotransmitter dopamine.

People who have 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.

You’re looking for evidence from a clinician of the diagnosis, but knowing the signs and symptoms is helpful as well.

Narrow Focus to These Codes

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 clinician 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) Note: This diagnosis is considered Return to Provider for the Patient-Driven Payment System (PDPM).
• 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.