Diagnosis and Treatment of Pulmonary Infection in Adults

While the idea of a pulmonary infection can sound incredibly scary, the reality is that most adults will experience these from time to time, in varying degrees of severity. Some infections clear easily, while others could persist and lead to chronic problems or indicate an underlying disease.

Fortunately, physicians can easily identify lung infections and treat them in most cases, and we will look at how they are diagnosed below. First, we will dive into why we get them in the first place, common symptoms, and more.

X-ray CT scan


Anyone can experience a lung infection – even otherwise healthy adults. However, some documented risk factors will increase your chances.

These common risk factors for lung infections include:

  • A history of smoking, past or present
  • Exposure to secondhand smoke
  • A history of asthma and/or allergies
  • Gastroesophageal reflux disease (GERD)
  • The presence of nasal polyps or a deviated septum
  • Malnutrition
  • Lack of vaccinations

While these are not the only risk factors when it comes to developing infections in the lungs, these are some of the most common. Patients with lung diseases such as COPD are especially at high risk for infections and have to monitor new symptoms closely with their physicians.


Pulmonary infections are a subset of a group known as respiratory infections. When we designate upper respiratory tract infections, we are talking about things that affect our noses, sinuses, and throats (for example, tonsillitis, sinus infections, and laryngitis are all upper respiratory infections).

When we move down to the airways and lungs, these infections are known as lower respiratory infections, including pulmonary infections (or lung infections). Among the most common are bronchitis and pneumonia, two illnesses that affect millions of adults each year.

The sources of the infections are typically bacterial or viral, but in some rare cases, the infection could be fungal. These infections can start in the airways and travel to the lungs; in some minor cases, they may clear on their own, and in other cases may require medical intervention or even hospitalization.

Chronic Lung Infections

In cases where infection does not clear with treatment, the patient may have a chronic lung infection, including Chronic Obstructive Pulmonary Disorder (COPD), bronchiectasis, or Cystic Fibrosis. These diseases are marked by a disability to remove or expel mucus, a loss of respiratory muscle strength and stamina, and general fatigue.

Smoking is a huge factor in chronic lung infections, and those with a damaged gag or swallowing reflexes (for example, after a stroke) are also at risk.

This is because the diminished gag and swallowing reflex increases the likelihood of aspiration, where food and drink intended for the patient’s esophagus make their way into the lungs, where they can create bacterial growth.

Chronic lung infections can be diagnosed in various ways, including blood and sputum tests and pulmonary function testing. Anyone suffering from chronic lung infections should be evaluated for the possibility of lung disease.


Many lung infections are short-term illnesses that can be treated effectively with rest and medication; they do not always indicate a serious disease. They are often associated with other viruses, such as a common cold or influenza.

Understanding the cause of the infection is key to treating it appropriately. (Spoiler alert: not all lung infections can be treated with antibiotics!)

When it comes to the root causes of the infections, we divide them into three categories:

  • Viral
  • Bacterial
  • Fungal

A viral pulmonary infection starts when a virus enters your body (such as influenza) and then attacks your lungs. This kind of respiratory viral infection cannot be treated by an antibiotic. In most cases, patients simply have to “tough it out,” though their physicians may advise over-the-counter medications for relief or prescribed antiviral medicine.

Diagnosis and Treatment of Pulmonary Infection in Adults

Bacterial infections in the lungs must be treated with antibiotics, on the other hand. When we think of bacterial infections that cause respiratory symptoms, mucus with a greenish or yellowish hue is one of the most telltale signs.

And the bacteria we think of most often at the root of such infections is streptococcus pneumoniae, the same bacteria that leads patients to develop “strep throat.” Many individuals also experience bacterial bronchitis at some point in their lives or even bacterial pneumonia.

A fungal pulmonary infection is less common, but it can be a serious risk for those with compromised immune systems due to conditions such as HIV. Fungal pulmonary infections can occur in damp or moldy environments where an individual is breathing in tiny spores, turning into a lung infection.

Aspergillosis is one such infection, which happens as a result of breathing in Aspergillus spores. Most of us can do so without any problem; however, these spores could cause an issue for an immunocompromised individual. Antifungal drugs are used in treatment, and in some extreme cases of invasive fungal infections, surgery may also be required.

Chronic pulmonary aspergillosis is a rare but serious condition that is sometimes diagnosed after an individual has experienced unintentional weight loss over a period of time along with consistent cough, fatigue, and in most cases, another underlying condition, such as asthma, lung cancer, or tuberculosis.


While there may be some variation in symptoms based on the type of infection (viral, bacterial, or fungal), most pulmonary infections will present with the following common signs:


One of the most obvious signs of an infection is a fever, as this is your body’s built-in defense mechanism. A fever signals that your body is trying to fight off something. In many cases, it will go away on its own, but a high fever (more than 102 degrees) that lasts for more than three days is always a sign you need to see your doctor.


Cough with Mucus

If you have only a dry cough, it is unlikely you are experiencing a pulmonary infection. Instead, these illnesses are characterized by a “wet cough,” or one that produces mucus. In some cases, you may even find that you cough up some blood along with the mucus.

While a cough is one of the most bothersome characteristics of a pulmonary infection, it is another way your body tries to fight infection. The coughing is designed to expel mucus from your airways, which in turn will make it easier to breathe.

Achiness and Fatigue

It is not uncommon to experience achiness, especially in your chest and back, when you have a lung infection. Similarly, fatigue is a common symptom with any infection, as your body fights to heal itself. This is why rest is one of the most important things physicians emphasize for patients with pulmonary infections.

Chest pain of any degree should always be taken seriously and reported to your physician.

Wheezing and Shortness of Breath

When airways are inflamed, patients may hear a whistling sound as they breathe. Wheezing is a familiar sensation to asthma sufferers, but it will be jarring for those experiencing a lung infection for the first time. Even if the infection does not cause wheezing, it will likely cause shortness of breath in general.

Nasal Congestion

Lung infections are often accompanied by bothersome nasal congestion, so a runny or stuffy nose, along with sneezing, may be another symptom patients experience.

Lung Sounds

Wheezing is not the only sign that your lungs may be infected. Other sounds may come from your airways signaling the infection, including what is known as “crackling.” These sounds could also indicate the presence of lung disease, so you should always let your physician know if you hear new sounds from your lungs. Whooping cough is another example of an infection that presents with sounds from the chest, hence the name.

Bluish Skin or Lips

When your airways are inflamed, and you are not receiving enough oxygen, your lips or skin may start to look bluish, which is another telltale sign of a possible pulmonary infection.

If you are experiencing any or all of the symptoms outlined here, contact your doctor.


Once you let your doctor know about the symptoms you are experiencing, she will ask a number of questions to determine what may be causing the illness and to evaluate you for the potential of a more serious disease. These could include questions about exposure to environmental factors (such as pollution or secondhand smoke), any allergies, and travel history.

Your healthcare provider will check your temperature, listen to your chest with a stethoscope, check your vital signs, and may take a nasal swab as well.

In addition to these initial steps, some physicians may also:

  • Order a chest x-ray
  • Order blood tests
  • Check pulse oximetry (which measures the level of oxygen found in your blood)

Order blood tests


If your physician diagnoses a lung infection, your treatment will depend upon whether your infection is bacterial, viral, or (in rare cases) fungal.

A patient with a bacterial pulmonary infection will be treated with antibiotics; a viral infection will need to clear on its own, but the physician may be able to prescribe medications to ease symptoms.

Your doctor may also recommend some of the following measures to provide relief:

  • An over-the-counter fever reducer
  • Plenty of liquids to prevent dehydration
  • Sipping on hot tea
  • Using a humidifier


Any time you are experiencing shortness of breath, you should contact your doctor right away. While in many cases, a lung infection will clear up with a simple treatment plan, some of these symptoms could also indicate a more serious disease, such as COPD or lung cancer. Also, any immunocompromised patient should have symptoms evaluated by a medical professional immediately.