ICD-10-CM Diagnosis Code J42 - Unspecified chronic bronchitis (original) (raw)

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Unspecified chronic bronchitis

ICD-10-CM Code:

J42

ICD-10 Code for:

Unspecified chronic bronchitis

Is Billable?

Yes - Valid for Submission

Chronic Condition Indicator: [1]

Chronic

Code Navigator:

J42 is a billable diagnosis code used to specify a medical diagnosis of unspecified chronic bronchitis. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2025 through September 30, 2026.

Unspecified diagnosis codes like J42 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

  1. Code Information
  2. Approximate Synonyms
  3. Clinical Classification
  4. Clinical Information
  5. Tabular List of Diseases and Injuries
  6. Index to Diseases and Injuries References
  8. Diagnostic Related Groups Mapping
  9. Convert to ICD-9 Code
  10. Patient Education
  11. Code History

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

CCSR Code: RSP008

Inpatient Default: Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

inflammation of the large airways in the lung including any part of the bronchi, from the primary bronchi to the tertiary bronchi.

a subcategory of chronic obstructive pulmonary disease. the disease is characterized by hypersecretion of mucus accompanied by a chronic (more than 3 months in 2 consecutive years) productive cough. infectious agents are a major cause of chronic bronchitis.

a species of coronavirus causing infections in chickens and possibly pheasants. chicks up to four weeks old are the most severely affected.

a member of coronaviridae which causes respiratory or gastrointestinal disease in a variety of vertebrates.

acute upper respiratory airways infection that results in the swelling of the larynx. it is usually caused by parainfluenza viruses. signs include a characteristic barking cough and stridor.

inflammation of the tracheobronchial tree.

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

References found for this diagnosis code in the External Cause of Injuries Index:

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

ICD-9-CM: 491.9

This is a direct match with no additional mapping qualifiers. The absence of a flag generally means the mapping is considered exact or precise. In other words, the ICD-10 code maps cleanly to the ICD-9 code without qualification, approximation, or needing multiple codes.

Chronic Bronchitis

What is chronic bronchitis?

Chronic bronchitis is a type of COPD (chronic obstructive pulmonary disease). COPD is a group of lung diseases that make it hard to breathe and get worse over time. The other main type of COPD is emphysema. Most people with COPD have both emphysema and chronic bronchitis, but how severe each type is can be different from person to person.

Chronic bronchitis is inflammation (swelling) and irritation of the bronchial tubes. These tubes are the airways that carry air to and from the air sacs in your lungs. The irritation of the tubes causes mucus to build up. This mucus and the swelling of the tubes make it harder for your lungs to move oxygen in and carbon dioxide out of your body.

What causes chronic bronchitis?

The cause of chronic bronchitis is usually long-term exposure to irritants that damage your lungs and airways. In the United States, cigarette smoke is the main cause. Pipe, cigar, and other types of tobacco smoke can also cause chronic bronchitis, especially if you inhale them.

Exposure to other inhaled irritants can contribute to chronic bronchitis. These include secondhand smoke, air pollution, and chemical fumes or dusts from the environment or workplace.

Rarely, a genetic condition called alpha-1 antitrypsin deficiency can play a role in causing chronic bronchitis.

Who is at risk for chronic bronchitis?

The risk factors for chronic bronchitis include:

What are the symptoms of chronic bronchitis?

At first, you may have no symptoms or only mild symptoms. As the disease gets worse, your symptoms usually become more severe. They can include:

Some people with chronic bronchitis get frequent respiratory infections such as colds and the flu. In severe cases, chronic bronchitis can cause weight loss, weakness in your lower muscles, and swelling in your ankles, feet, or legs.

How is chronic bronchitis diagnosed?

Your health care provider may use many tools to make a diagnosis:

What are the treatments for chronic bronchitis?

There is no cure for chronic bronchitis. However, treatments can help with symptoms, slow the progress of the disease, and improve your ability to stay active. There are also treatments to prevent or treat complications of the disease. Treatments include:

If you have chronic bronchitis, it's important to know when and where to get help for your symptoms. You should get emergency care if you have severe symptoms, such as trouble catching your breath or talking. Call your health care provider if your symptoms are getting worse or if you have signs of an infection, such as a fever.

Can chronic bronchitis be prevented?

Since smoking causes most cases of chronic bronchitis, the best way to prevent it is to not smoke. It's also important to try to avoid lung irritants such as secondhand smoke, air pollution, chemical fumes, and dusts.

NIH: National Heart, Lung, and Blood Institute

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