What To Know About Double Pneumonia—An Infection in Both Lungs

Bilateral Interstitial Pneumonia

Bilateral interstitial pneumonia is a serious infection that can inflame and scar your lungs. It’s one of many types of interstitial lung diseases, which affect the tissue around the tiny air sacs in your lungs. You can get this type of pneumonia as a result of COVID-19.

Bilateral types of pneumonia affect both lungs. In bilateral interstitial pneumonia, the tissue around your air sacs (interstitial tissue) get irritated and may fill with pus and other fluids. As the pneumonia gets worse, your lungs can develop permanent scars.

When interstitial tissue gets scarred, it may stiffen and make it hard for you to breathe. Your condition can quickly get worse, leading to respiratory failure.

Links to COVID-19

Infection by bacteria or viruses is one cause of pneumonia. Infected people cough or sneeze particles into the air that you breathe or onto surfaces that you touch. You can get pneumonia as a result.

The new coronavirus is also spread by contact with droplets spread into the air or onto a surface when someone who is infected coughs or sneezes. Most people who get it have only mild symptoms similar to a cold or the flu. But others end up with severe pneumonia as a complication of COVID-19.

Symptoms

Bilateral interstitial pneumonia symptoms often include:

• Fever
• Dry cough
• Shortness of breath
• Hard time breathing
• Fatigue

Warning signs of COVID-19 are similar.

Diagnosis

In people with serious COVID-19 symptoms, doctors may use CT scans to look for signs of pneumonia. These powerful X-rays show visual signs of damage to your lungs.

When people with bilateral interstitial pneumonia have CT scans, doctors can often see white patches they call “ground glass.” These are a sign of sores on the lungs.

If you have symptoms of interstitial lung disease but aren’t thought to have COVID-19, your doctor will start by giving you a physical exam. They may also give you some tests to rule out other problems. These include chest X-rays and CT scans as well as:

• Pulmonary function test. These tests measure how well your lungs are working. The doctor may ask you to exhale into a tube for this type of test.
• Bronchoscopy. In this test, your doctor inserts a long, flexible tube into your lungs to flush out your airways with saline solution. They’ll remove the fluid and examine it. They’re looking for high levels of white blood cells in your lungs. This is seen in about half of people with interstitial pneumonia.
• Biopsy. It’s not always necessary, but your doctor may remove a small piece of lung tissue during your bronchoscopy to test for signs of inflammation or scarring.

Treatment

While most cases of COVID-19 are mild, your doctor may prescribe an antiviral medicine to keep your symptom from getting worse. The antiviral that doctors prefer to use is a pill called ritonavir-boosted nirmatrelvir (Paxlovid) which has been given emergency use authorization from the FDA. Remdesivir (Veklury), which is given by IV is the only antiviral drug that has full FDA approval. A EUA has also been given to the antiviral molnupiravir (Lageviro) but that should only be used when the other treatments are not available.

If you get pneumonia as a result of the virus, your doctor may help you breathe by giving you oxygen through a mask or tubes. If it’s very serious, you might need a breathing machine.

If you’re diagnosed with interstitial pneumonia, your doctor may prescribe oral corticosteroids like prednisone. But they don’t work for everyone. They can also have lots of side effects.

Drugs that suppress your immune system may help, too. These include:

• Azathioprine (Imuran)
• Cyclophosphamide (Cytoxan)
• Mycophenolate mofetil (CellCept)
• Mycophenolic acid (Myfortic)
• Rituximab (Rituxan)

Some people take steroids along with one of these drugs.

Once your lungs are scarred, you can’t reverse the damage. But anti-fibrotic drugs like nintedanib (Ofev) and pirfenidone (Esbriet) help keep the scarring from getting worse.

Other treatments include oxygen therapy and pulmonary rehab, which includes breathing exercises to improve your lung strength. If nothing else works for you, you might need a lung transplant.

Prevention

To keep your lungs healthy, don’t smoke. To prevent any infection, including COVID-19:

• Wash your hands often with soap and water for at least 20 seconds.
• Avoid touching your hands, eyes, or mouth until you’ve washed your hands.
• Use hand sanitizer gels that are at least 60% alcohol if you’re not in a place where you can wash your hands.
• Stay away from others who are sick. Keep a safe distance when you go out.
• Stay home if you’re sick except to go to the doctor.

Show Sources

Case Reports in Medicine: “Acute Interstitial Pneumonia (Hamman-Rich Syndrome) as a Cause of Idiopathic Acute Respiratory Distress Syndrome.”

National Jewish Health: “Interstitial Lung Disease (ILD) Overview.”

Cleveland Clinic: “Nonspecific Interstitial Pneumonia,” “Pneumonia.”

Radiopaedia.org: “Coronavirus disease 2019 (COVID-19).”

American Journal of Roentgenology: “Relation Between Chest CT Findings and Clinical Conditions of Coronavirus Disease (COVID-19) Pneumonia: A Multicenter Study.”

Johns Hopkins Medicine: “Pulmonary Function Tests.”

CDC: “Coronavirus Disease 2019 (COVID-19): How to Protect Yourself,” “Information for Clinicians on Therapeutic Options for COVID-19 Patients.”

Radiology: “Artificial Intelligence Distinguishes COVID-19 from Community Acquired Pneumonia on Chest CT.”

What To Know About Double Pneumonia—An Infection in Both Lungs

Bilateral pneumonia affects both lungs and may be more serious than pneumonia in a single lung.

Updated on November 29, 2022
Medically reviewed by

Susan Bard, MD, is a board-certified general and procedural dermatologist with the American Board of Dermatology and a Fellow of the American College of Mohs Surgery.

A pneumonia diagnosis can be a scary thing to hear—it means that you have an infection in your lungs that is causing inflammation and fluid buildup, and it can result in distressing symptoms, like chest pain, fever, and shortness of breath.

When giving a diagnosis of pneumonia, healthcare providers may tell you whether you’ve got a bacterial or viral infection, whether it’s in different spots of the lung, and if it’s confined to a single lung or has taken up residence in both.

Pneumonia that affects both lungs is colloquially known as “double pneumonia,” but healthcare providers are more likely to call it “bilateral pneumonia.” And while double or bilateral pneumonia doesn’t differ too much from pneumonia that affects a single lung, when the infection, inflammation, and fluid affect a larger area of the lungs, it is likely to be more serious.

Here’s what you need to know about pneumonia that affects both lungs, including the most common symptoms, the likeliest causes, and the treatment options healthcare providers typically use.

Definition of Double Pneumonia

Double or bilateral pneumonia is a term used when there’s inflammation caused by an infection in the air sacs in both lungs, Thomas Monaco, MD, assistant professor of pulmonary and critical care medicine at the Baylor College of Medicine, told Health.

The parts of the lungs that are affected by pneumonia—either bilateral (double, or both lungs) or unilateral (single, or one lung)—are called the alveoli. Alveoli are the small, balloon-shaped air sacs in the lungs that move oxygen into and carbon dioxide out of your bloodstream.

When those air sacs become infected and inflamed, they begin to fill up with fluid or pus, according to the National Heart, Lung, and Blood Institute (NHLBI). That, in turn, can cause all of those unwelcome symptoms like cough, fever, chills, and difficulty breathing.

Symptoms

There’s no real difference in the type of symptoms of double pneumonia versus pneumonia that affects a single lung, Raymond Casciari, MD, a pulmonologist at St. Joseph Hospital in Orange, California, told Health. But because double pneumonia affects both lungs, it may feel more severe. “With single pneumonia, you can get chest pain, but it will only be on one side,” Dr. Casciari said and added, “With double, it may be on both sides.”

Generally speaking, the most common symptoms of pneumonia, per the NHLBI, include:

• Chest pain when you breathe or cough
• Chills
• Cough with or without mucus
• Fever
• Low oxygen levels in your blood, measured with a pulse oximeter
• Shortness of breath

Some people with pneumonia may also experience other symptoms like headache, muscle pain, fatigue, nausea, vomiting, and diarrhea, NHLBI says.

Pneumonia is usually caused by bacteria, viruses, or fungi—and that’s true whether you have double or single pneumonia, Dr. Casciari said. However, Dr. Casciari added that viral infections are usually more likely to show up in both lungs.

“The list of infections that can cause pneumonia of both lungs is long, but viral infections are a common offender,” Dr. Monaco said, citing SARS-CoV-2, or the virus that causes COVID-19, as a prime example.

Dr. Monaco noted a type of bacteria that can also lead to double pneumonia. “There are also a group of atypical bacteria [Mycoplasma pneumoniae] that cause pneumonia, a less severe, more mild case of the illness,” Dr. Monaco said.

Another form of bacteria—Legionella pneumophila—is also known to affect both lungs quite extensively, Reynold Panettieri, MD, a pulmonary critical care expert, and director of the Institute for Translational Medicine and Science at Rutgers University, told Health.

But it’s not always about the type of microbe that caused the infection—a person’s underlying risk factors matter too, Shweta Sood, MD, a pulmonologist and assistant professor of clinical medicine at Penn Medicine, told Health. The following factors, per the NHLBI, can raise your risk of having more severe pneumonia:

• Being a smoker
• Being a heavy drinker
• Having heart disease
• Having lung diseases, like asthma or chronic obstructive pulmonary disease (COPD)
• Being immunocompromised
• Being very young or very old
• Having another underlying disease, like diabetes or cancer

Treatment

Treatment usually depends on what caused your pneumonia in the first place, Dr. Sood said. Here’s a breakdown of possible treatments:

• Antibiotics: “If someone is relatively healthy and they get bacterial pneumonia, we can usually treat them as an outpatient with antibiotics,” Dr. Sood said. In more severe cases, you’ll need IV antibiotics in the hospital.
• Rest: Healthcare providers usually recommend rest and fluids if you have viral pneumonia. If you have viral double pneumonia, you may not need any medication, Dr. Panettieri explained.
• Antivirals: In severe situations, an antiviral medication like remdesivir may help, Dr. Casciari said.
• Antifungals: An antifungal medication can help treat fungal pneumonia, Dr. Sood said. And, like antibiotics, if you have a more severe form of double pneumonia, you may be given the medication through an IV.
• Breathing support: “Patients with pneumonia in both lungs are more likely to need supplemental oxygen or possibly support from a mechanical ventilator,” Dr. Monaco added.

As far as prognosis goes, it’s important to note that pneumonia is one of the top 10 causes of death in the United States, per the Centers for Disease Control and Prevention—and “it’s serious, but even worse when it involved both lungs,” Dr. Casciari cautioned.

When To See a Healthcare Provider

If you develop double pneumonia, though, don’t panic. “Fortunately, most patients with pneumonia will recover without any long-lasting effects,” Dr. Monaco said.

If you do begin to feel any of the symptoms most commonly associated with pneumonia, it’s best to let a healthcare provider know. Healthcare providers will want to take a thorough look if you come in with symptoms of pneumonia.

Symptoms that signal an emergency include severe trouble breathing, a very high fever, or extreme chest pain. If you are feeling any of these symptoms, seek medical care immediately.