Despite preventive vaccines and antibiotic therapy, pneumonia remains a common illness throughout the world. Approximately 2 million to 3 million cases of pneumonia occur annually among adults and children in the United States, according to the Merck Manual 146.

Most cases of pneumonia occur due to a viral or bacterial infection of the small lung airways and air sacs. It’s important to recognize the symptoms of pneumonia to enable early treatment and reduce the possibility of serious complications.

Bronchial Pneumonia Definition

Your lungs consist of five regions called lobes, two in the left lung and three in the right. Medical professionals frequently categorize pneumonia based on the pattern of lung involvement seen on chest X-ray.

With bronchial pneumonia (also known as bronchopneumonia), the infection involves multiple patchy areas of one or both lungs. This contrasts with lobar pneumonia, in which the infection remains confined to a single lung lobe.

Although the distinction between bronchial and lobar pneumonia proves useful in determining possible underlying causes, the symptoms that occur with both types of pneumonia mirror one another.

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Common Pneumonia Symptoms

Pneumonia symptoms vary with a person’s age and the cause and severity of the infection. Common symptoms include cough, fever, shortness of breath, fatigue and chest discomfort.

Infants, toddlers, seniors and people with weak immune systems due to illness or medication use tend to experience more severe symptoms compared to others with pneumonia.

1. Cough

It probably comes as no surprise that cough tops the list of pneumonia symptoms. The infection triggers inflammation in the air sacs and small airways as well as increased mucus production and an accumulation of pus. These factors stimulate the cough reflex.

Bacterial pneumonia typically causes a productive cough, meaning one that involves coughing up thick, sticky phlegm. The mucus often appears yellowish and sometimes contains streaks of blood.

In contrast, people with viral pneumonia and certain types of mild bacterial pneumonia typically experience a dry, hacking cough often accompanied by wheezing.

2. Fever

Bacterial pneumonia commonly causes a fever of 102 degrees Fahrenheit or greater, often accompanied by chills, shivering and/or cold sweats. With viral pneumonia, fever tends to be low grade (101.3 degrees Fahrenheit or less) or absent, as noted by the Family Practice Notebook website 24. With viral pneumonia, the fever commonly precedes the development of lung-related symptoms.

Notably, young infants and seniors with pneumonia sometimes do not develop a fever. In fact, some experience an abnormally low body temperature. This occurs due to a propensity for disordered temperature regulation among people in these age groups.

3. Breathing Difficulty

The excess mucus production and pus accumulation that occurs with pneumonia often interferes with the exchange of oxygen and carbon dioxide between the lungs and bloodstream. This leads to breathing difficulty that manifests as abnormally fast breathing and/or a sensation of shortness of breath, also known as air hunger.

Shortness of breath frequently leads to anxiousness and distress with extensive pneumonia as people struggle to get enough air. With severe cases, a reduced blood oxygen level can lead to mental symptoms like confusion, agitation or irritability.

4. Fatigue

People with pneumonia often experience fatigue, especially with a bacterial infection. The lack of energy and weakness result from a combination of factors, including immune system chemicals released into the bloodstream, disrupted sleep due to coughing and increased energy utilization caused by working harder to breathe and fighting the infection.

5. Chest Discomfort

Coughing due to pneumonia often triggers chest discomfort. Chest muscle soreness caused by frequent, hard coughing feels much like the muscle soreness in the arms or legs after an overzealous workout.

Sharp chest pain experienced when taking a deep breath or coughing — known as pleuritic chest pain — develops when the infection irritates the thin sac that encases the lung. This complication, however, occurs only in some cases of pneumonia.

Less Common Symptoms

Pneumonia sometimes causes other, less common symptoms. Bronchial pneumonia in particular often develops after a cold, bronchitis or influenza. As such, the more common symptoms of bronchial pneumonia already discussed can be preceded by a runny nose, nasal stuffiness, sneezing, throat soreness, headache and/or body aches.

Digestive system symptoms can also occur with pneumonia, especially among infants and young children. These include nausea with or without vomiting, abdominal discomfort and/or diarrhea.

With severe pneumonia, a markedly reduced blood oxygen level can lead to bluish discoloration of the lips, fingernails and toenails.

Pneumonia Symptoms in Infants and Toddlers

Infants and toddlers with pneumonia often present with less obvious symptoms than older children and adults. Although cough and fever occur commonly, they do not reliably distinguish pneumonia from less serious airway infections, such as a cold.

These symptoms along with a rapid breathing, however, strongly suggest pneumonia, as reported in a 2010 American Family Physician review article 23. Other possible symptoms of pneumonia in infants and young children include 34:

• Reduced or poor feeding
  
• Unusual fussiness, irritability and/or reduced activity level
• Obvious inward movement of the chest muscles (known as retractions) as the child works harder to breath
• Fewer wet diapers due to dehydration and decreased urination

Read more: How to Differentiate Between Bronchiolitis and Pneumonia in Children

Diagnosis

Symptoms often point to a diagnosis of pneumonia, which is usually confirmed by findings on the physical examination. When listening to the lungs with a stethoscope, findings include decreased breath sounds and a crackling noise heard over the affected areas. The doctor also often taps gently on the chest, listening for dullness that indicates fluid in the lungs.

A chest X-ray or lung ultrasound test distinguishes bronchial from lobar pneumonia. Laboratory tests are sometimes used to determine the specific bacteria or virus responsible for pneumonia.

When to See a Doctor

Pneumonia is a treatable but potentially life-threatening illness. For this reason, it’s crucial to see your doctor right away if you or your child develop symptoms suggestive of pneumonia. This is particularly important for people at risk for a severe case of pneumonia, including infants, toddlers, seniors, pregnant women and those with a weakened immune system or pre-existing heart or lung disease.

Seek emergency medical evaluation and treatment if you or your child experience warning signs or symptoms, including:

• Sudden, severe or worsening chest pain
  
• Sudden, severe or worsening shortness of breath
• Mental changes, such as confusion or reduced consciousness
• Dizziness, lightheadedness or fainting

Treatment for pneumonia varies according to the severity of the infection, ranging from outpatient treatment with antibiotic or antiviral medication to hospitalization with possible intensive care and assisted ventilation with a breathing machine.

And if you’re wondering: “Is pneumonia contagious?” It’s important to note that bacterial and viral pneumonia are variably contagious depending on the organism responsible. So your doctor will advise you about precautions to avoid spread of the infection to others.

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