Eosinophilic Pneumonia: Causes, Symptoms, and Treatment
Medically reviewed by Sumiran Racherla, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Eosinophilic Pneumonia?
A pulmonologist (a lung doctor) usually leads care for eosinophilic pneumonia. Some cases are linked to other conditions, so an allergist (a doctor who treats allergies and immune problems) or a rheumatologist (a doctor who treats immune and joint diseases) may also help. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is eosinophilic pneumonia?
Eosinophilic pneumonia is a group of rare lung diseases. In these diseases, eosinophils build up in the lungs. Eosinophils are a type of white blood cell and are part of the immune system.
One type, acute eosinophilic pneumonia (AEP), starts suddenly, usually within 1 to 7 days. The other type, chronic eosinophilic pneumonia (CEP), develops slowly, over weeks or months.
Eosinophilic pneumonia may have no known cause, or it may be due to known causes such as medicines or things in the environment.
Symptoms
Common symptoms of CEP include shortness of breath, cough, tiredness, night sweats, low fevers, and weight loss without trying. Wheezing occurs in about half of people with CEP. Some people with CEP have asthma or a history of allergies.
AEP comes on suddenly. Symptoms can include fever, cough, trouble breathing, and chest pain.
AEP can quickly cause acute respiratory failure. This means the level of oxygen in the blood drops severely. It can happen within a few days or even within hours.
Causes and who gets it
Doctors do not know the exact cause of chronic eosinophilic pneumonia. The cause of acute eosinophilic pneumonia is also unknown in many people.
Smoking is linked to AEP. This is most often seen in people who just began smoking or started again after a break. It is also seen in people who recently smoked more.
Breathing in dust or smoke at work can trigger AEP.
Some cases are linked to medicines, such as certain antibiotics and NSAIDs (nonsteroidal anti-inflammatory drugs, a type of pain reliever). Some are linked to infections.
AEP affects males about twice as often as females. It occurs most often between ages 20 and 40.
CEP is twice as common in women as in men. It is extremely rare in childhood.
How doctors diagnose it
Doctors use your symptoms, your history, and an exam. They must also check for other causes, such as parasite infections or certain drugs.
A chest x-ray or CT scan, which is a detailed x-ray picture, can help confirm CEP. In CEP, x-rays generally show white patches in the outer parts of the lungs.
A test called bronchoalveolar lavage (BAL) is key to diagnosing AEP. A thin tube is passed down the windpipe into the lungs. A sterile liquid washes out cells, which are then studied. BAL can also help diagnose CEP.
In CEP, blood tests may show high levels of eosinophils or IgE, an antibody involved in allergies. In AEP, the blood eosinophil count is often not high at first.
AEP can be mistaken for pneumonia caused by an infection.
Treatment
People with CEP respond quickly, and often very well, to corticosteroids taken by mouth, such as prednisone. Corticosteroids are steroid medicines that lower inflammation. Improvement is often seen within one to two weeks.
CEP often comes back, especially if steroid treatment is stopped within the first 6 months. In some cases, even lowering the steroid amount can bring it back. Follow your doctor's instructions about steroid medicine. Many people need steroids for a long time, which can cause side effects.
People with AEP respond within days to corticosteroids, which are usually prescribed for two weeks. Doctors start steroids only after ruling out an infection as the cause. AEP does not come back after steroid treatment is stopped. The long-term outlook is excellent.
Many people with AEP need care in an intensive care unit for breathing support.
When to see a doctor
CEP can build slowly over weeks or months. See a doctor if a cough or shortness of breath keeps getting worse.
AEP can get worse within a few days or even within hours.
Call 911 or go to the emergency room if you have severe trouble breathing, chest pain or discomfort lasting two minutes or more, or fainting.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Such a doctor can review your symptoms, order first tests such as a chest x-ray, and help coordinate care with a lung specialist.
Common questions
Is eosinophilic pneumonia serious?
It can be. Acute eosinophilic pneumonia can quickly lead to acute respiratory failure, and many people need intensive care. With steroid treatment, the long-term outlook for AEP is excellent.
Does eosinophilic pneumonia come back?
It depends on the type. Chronic eosinophilic pneumonia tends to come back, especially if treatment is not kept up. A relapse can happen 10 years or more later. Acute eosinophilic pneumonia does not come back after steroid treatment is stopped.
What is the difference between acute and chronic eosinophilic pneumonia?
Acute eosinophilic pneumonia starts suddenly, while chronic eosinophilic pneumonia develops slowly. Acute eosinophilic pneumonia is more likely to cause acute respiratory failure, and chronic eosinophilic pneumonia does not progress to it. Chronic eosinophilic pneumonia comes back often and is often linked with asthma.
Can smoking cause eosinophilic pneumonia?
It may play a role in acute eosinophilic pneumonia. This is most often seen in people who just began smoking or started again after a break.
Sources
- National Organization for Rare Disorders (NORD) - Chronic Eosinophilic Pneumonia
- National Organization for Rare Disorders (NORD) - Acute Eosinophilic Pneumonia
- National Center for Biotechnology Information (PMC) - Acute and chronic eosinophilic pneumonia: an overview
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
