Drug-induced pulmonary pneumonitis and fibrosis

Drug-induced pulmonary pneumonitis and fibrosis

Drug-induced pneumonitis is a type of interstitial lung disease (ILD) caused by certain medications you might be taking. Pneumonitis is a general term used by health professionals to refer to infectious or noninfectious reasons for lung inflammation. Since this inflammation can lead to difficulty breathing, it’s important to identify the cause and find alternatives to the drugs or medical treatments responsible for it.

Causes of drug-induced pulmonary pneumonitis

Dozens of different medications can be responsible for the inflammation seen in the lungs of patients with pneumonitis. They range from cancer treatments to over-the-counter medications.

Drugs are known to cause pneumonitis to include:

• Several types of chemotherapy
• Medications for irregular heart rhythms
• Some antibiotics
• Radiation treatments to the chest can also cause pneumonitis.

Symptoms of Pulmonary Pneumonitis 

Symptoms may include any of the following:

• Bloody sputum
• Chest pain
• Cough
• Fever
• Shortness of breath
• Wheezing

Diagnosis

The healthcare provider will perform a physical exam and listen to your chest and lungs with a stethoscope. Abnormal breath sounds may be heard.

Tests that may be done include:

• Arterial blood gases
• Blood test to check for an autoimmune disorder
• Blood chemistry
• Bronchoscopy
• Complete blood count with blood differential
• Chest CT scan
• Chest x-ray
• Lung biopsy (in rare cases)
• Lung function tests
• Thoracentesis (if pleural effusion is present)

Drug-Induced Pulmonary fibrosis

Pulmonary fibrosis (PF) is part of a larger group of more than 200 interstitial lung diseases (also known as ILDs) that are characterized by inflammation and/or scarring in the lung. In ILDs, the injury and damage occur in the walls of the air sacs of the lung, as well as in the tissue and space around these air sacs. When an interstitial lung disease includes scar tissue in the lung, it is called pulmonary fibrosis.

Causes of drug-induced pulmonary fibrosis

Drugs that can cause pulmonary fibrosis include:

• the antibiotic nitrofurantoin
• anti-cancer drugs such as bleomycin
• cardiac medications such as amiodarone and
• biological therapies used for treating cancer and autoimmune diseases.

If you have pulmonary fibrosis, it is advisable to avoid these medications. Drug-induced pulmonary fibrosis can be an idiosyncratic reaction. 

Symptoms of drug-induced pulmonary fibrosis

The symptoms include: 

• Cough
• Breathlessness
• Fevers
• Fatigue
• joint pains

Diagnosis

When a doctor or other healthcare provider suspects that a patient has ILD, they will collect information about the patient’s medical and personal history, work and home environment, hobbies, and illness that may be present in the family). This can help a doctor identify exposures or other diseases that might have caused lung injury and scarring. 

The doctor will also often order the following tests:

• pulmonary function tests
• chest x-ray
• blood work
• high-resolution CT scan.

General Rating Formula for Interstitial Lung Disease (diagnostic codes 6825 through 6833):