2024 ICD-10-CM Diagnosis Code G12.21

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

• Amyotrophic lateral sclerosis
• Amyotrophic lateral sclerosis plus syndrome
• Amyotrophic lateral sclerosis plus syndrome
• Amyotrophic lateral sclerosis plus syndrome
• Amyotrophic lateral sclerosis plus syndrome
• Amyotrophic lateral sclerosis plus syndrome
• Amyotrophic lateral sclerosis plus syndrome
• Amyotrophic lateral sclerosis type 1
• Amyotrophic lateral sclerosis type 10
• Amyotrophic lateral sclerosis type 3
• Amyotrophic lateral sclerosis type 4
• Amyotrophic lateral sclerosis type 6
• Amyotrophic lateral sclerosis type 7
• Amyotrophic lateral sclerosis type 8
• Amyotrophic lateral sclerosis type 9
• Amyotrophic lateral sclerosis with autonomic dysfunction
• Amyotrophic lateral sclerosis with cerebellar dysfunction
• Amyotrophic lateral sclerosis with dementia
• Amyotrophic lateral sclerosis with dementia
• Amyotrophic lateral sclerosis with dementia
• Amyotrophic lateral sclerosis with frontotemporal dementia
• Amyotrophic lateral sclerosis with multiple system atrophy
• Amyotrophic lateral sclerosis with parkinsonism
• Amyotrophic lateral sclerosis with spinocerebellar ataxia
• Amyotrophic lateral sclerosis, parkinsonism, dementia complex
• Amyotrophic lateral sclerosis, parkinsonism, dementia complex of Kii Peninsula
• Amyotrophic lateral sclerosis, parkinsonism, dementia complex of West New Guinea
• Autosomal dominant amyotrophic lateral sclerosis type 1
• Autosomal recessive amyotrophic lateral sclerosis type 1
• Juvenile amyotrophic lateral sclerosis
• Juvenile amyotrophic lateral sclerosis type 2
• Juvenile amyotrophic lateral sclerosis type 5
• Multiple system atrophy
• Restrictive lung disease
• Restrictive lung disease due to amyotrophic lateral sclerosis
• Synucleinopathy

Clinical Information

• Amyotrophic Lateral Sclerosis

  a degenerative disorder affecting upper motor neurons in the brain and lower motor neurons in the brain stem and spinal cord. disease onset is usually after the age of 50 and the process is usually fatal within 3 to 6 years. clinical manifestations include progressive weakness, atrophy, fasciculation, hyperreflexia, dysarthria, dysphagia, and eventual paralysis of respiratory function. pathologic features include the replacement of motor neurons with fibrous astrocytes and atrophy of anterior spinal nerve roots and corticospinal tracts. (from adams et al., principles of neurology, 6th ed, pp1089-94)

• Multiple System Atrophy

  a syndrome complex composed of three conditions which represent clinical variants of the same disease process: striatonigral degeneration; shy-drager syndrome; and the sporadic form of olivopontocerebellar atrophies. clinical features include autonomic, cerebellar, and basal ganglia dysfunction. pathologic examination reveals atrophy of the basal ganglia, cerebellum, pons, and medulla, with prominent loss of autonomic neurons in the brain stem and spinal cord. (from adams et al., principles of neurology, 6th ed, p1076; baillieres clin neurol 1997 apr;6(1):187-204; med clin north am 1999 mar;83(2):381-92)

• Restrictive Lung Disease

  decreased lung volume and inadequate ventilation due to parenchymal lung disorders (e.g., interstitial pulmonary fibrosis) or extrapulmonary disorders (e.g., scoliosis). patients present with shortness of breath and cough.

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

• Adult diagnoses - The Medicare Code Editor detects inconsistencies in adult cases by checking a patient's age and any diagnosis on the patient's record. The adult code edits apply to patients age range is 15–124 years inclusive (e.g., senile delirium, mature cataract).

Convert G12.21 to ICD-9-CM

• ICD-9-CM Code: 335.20 - Amyotrophic sclerosis
  Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
• ICD-9-CM Code: 335.21 - Prog muscular atrophy
  Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education

Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a nervous system disease that attacks nerve cells called neurons in your brain and spinal cord. These neurons transmit messages from your brain and spinal cord to your voluntary muscles - the ones you can control, like in your arms and legs. At first, this causes mild muscle problems. Some people notice:

• Trouble walking or running
• Trouble writing
• Speech problems

Eventually, you lose your strength and cannot move. When muscles in your chest fail, you cannot breathe. A breathing machine can help, but most people with ALS die from respiratory failure.

The disease usually strikes between age 40 and 60. More men than women get it. No one knows what causes ALS. It can run in families, but usually it strikes at random. There is no cure. Medicines can relieve symptoms and, sometimes, prolong survival.

NIH: National Institute of Neurological Disorders and Stroke

[Learn More in MedlinePlus]

Amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive disease that affects motor neurons, which are specialized nerve cells that control muscle movement. These nerve cells are found in the spinal cord and the brain. In ALS, motor neurons die (atrophy) over time, leading to muscle weakness, a loss of muscle mass, and an inability to control movement.

There are many different types of ALS; these types are distinguished by their signs and symptoms and their genetic cause or lack of clear genetic association. Most people with ALS have a form of the condition that is described as sporadic, which means it occurs in people with no apparent history of the disorder in their family. People with sporadic ALS usually first develop features of the condition in their late fifties or early sixties. A small proportion of people with ALS, estimated at 5 to 10 percent, have a family history of ALS or a related condition called frontotemporal dementia (FTD), which is a progressive brain disorder that affects personality, behavior, and language. The signs and symptoms of familial ALS typically first appear in one's late forties or early fifties. Rarely, people with familial ALS develop symptoms in childhood or their teenage years. These individuals have a rare form of the disorder known as juvenile ALS.

The first signs and symptoms of ALS may be so subtle that they are overlooked. The earliest symptoms include muscle twitching, cramping, stiffness, or weakness. Affected individuals may develop slurred speech (dysarthria) and, later, difficulty chewing or swallowing (dysphagia). Many people with ALS experience malnutrition because of reduced food intake due to dysphagia and an increase in their body's energy demands (metabolism) due to prolonged illness. Muscles become weaker as the disease progresses, and arms and legs begin to look thinner as muscle tissue atrophies. Individuals with ALS eventually lose muscle strength and the ability to walk. Affected individuals eventually become wheelchair-dependent and increasingly require help with personal care and other activities of daily living. Over time, muscle weakness causes affected individuals to lose the use of their hands and arms. Breathing becomes difficult because the muscles of the respiratory system weaken. Most people with ALS die from respiratory failure within 2 to 10 years after the signs and symptoms of ALS first appear; however, disease progression varies widely among affected individuals.

Approximately 20 percent of individuals with ALS also develop FTD. Changes in personality and behavior may make it difficult for affected individuals to interact with others in a socially appropriate manner. Communication skills worsen as the disease progresses. It is unclear how the development of ALS and FTD are related. Individuals who develop both conditions are diagnosed as having ALS-FTD.

A rare form of ALS that often runs in families is known as ALS-parkinsonism-dementia complex (ALS-PDC). This disorder is characterized by the signs and symptoms of ALS, in addition to a pattern of movement abnormalities known as parkinsonism, and a progressive loss of intellectual function (dementia). Signs of parkinsonism include unusually slow movements (bradykinesia), stiffness, and tremors. Affected members of the same family can have different combinations of signs and symptoms.

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Code History

• FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
• FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
• FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
• FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
• FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
• FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
• FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
• FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
• FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.