What is Pneumonia?
Pneumonia is a serious lower respiratory tract infection that can affect one or both lungs. It’s a common but potentially severe disease with significant illness and death rates. In fact, pneumonia is the sixth leading cause of death in the United States and the only infection-related illness on the top ten list.
Pneumonia can be split into two types based on how a person gets the infection:
1. Community-acquired pneumonia (CAP): The most common type.
2. Hospital-based pneumonia. This category includes:
* Hospital-acquired pneumonia (HAP)
* Ventilator-associated pneumonia (VAP)
* Healthcare-associated pneumonia (HCAP)
Community-acquired pneumonia develops in people who aren’t hospitalized or in patients who were able to move about before being admitted to the hospital. We see this type mostly within 48 hours of a hospital admission. CAP has two sub-types: “typical” and “atypical.”
Hospital-acquired pneumonia develops more than 48 hours after a person is admitted to the hospital. If someone is on a ventilator (a machine that helps you breathe) for more than 48 hours, they can get a specific type of pneumonia known as VAP. Healthcare-associated pneumonia happens in people who aren’t in the hospital but have had a lot of contact with healthcare settings in the past three months.
What Causes Pneumonia?
Pneumonia is a lung infection that you can catch from the air. It can be caused by many things like bacteria, viruses, fungi, and parasites. Some typical bacteria that cause pneumonia include Streptococcus pneumoniae, Staphylococcus aureus, Group A Streptococcus, Klebsiella pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and many others.
The most common bacteria responsible for pneumonia worldwide is the Streptococcus pneumoniae. Other bacteria like Methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and others are often found in pneumonia caused by other diseases or health conditions.
Anyone can get pneumonia, but there are certain conditions that can make you more likely to catch it. Having a lower immune response due to things like being older than 65, having a suppressed immune system, diabetes, cystic fibrosis, or lung cancer can increase your risk. Conditions that increase your risk of getting tiny or large foreign bodies into your lungs, like stroke, seizures, anesthesia, or drug intoxication can also make you more likely to catch pneumonia. Lifestyle habits like smoking or drinking, not eating enough, or having a tumor blocking your bronchi (the tubes that allow air to enter and leave your lungs) are other common risk factors.
Risk Factors and Frequency for Pneumonia
Community-Acquired Pneumonia (CAP), affects 5-7 people out of every 1000 each year. It is more frequent in males, and its rate increases as people get older. CAP often occurs in the winter months. When combined with influenza, it can be very dangerous and has been a common cause of death. In fact, in 2005, pneumonia and influenza together were the eighth leading cause of death in the US and the seventh in Canada.
- Community-Acquired Pneumonia (CAP) affects 5-7 out of every 1000 people each year.
- The condition is more common in males and the risk increases with age.
- CAP is more likely to occur during the winter months.
- When combined with the flu, it can be very serious and often results in death.
- In 2005, pneumonia and influenza were among the top ten causes of death in both the US (eighth) and Canada (seventh).
Signs and Symptoms of Pneumonia
- Fever
- Coughing
- Production of sputum
- Pleuritic chest pain
- Fatigue
- Headache
- Muscle and joint pains
- Shortness of breath (in severe cases)
- Confusion, sepsis, and multi-organ failure (in severe cases)
- Quick and shallow breathing
Testing for Pneumonia
- Review of patient’s history
- Physical exam
- Chest x-ray
- Computed Tomography (CT)
- Blood tests
- Sputum staining and culture
- Influenza testing
- CURB-65 and Pneumonia Severity Index
- Sputum and blood cultures
- Urine antigen testing
- Thoracocentesis
- Bronchoscopy
- Pleural biopsy
- Pleural fluid culture
- Open lung biopsy (in specific cases)
Treatment Options for Pneumonia
Treatment for pneumonia depends on the severity of the condition. The CURB-65 pneumonia severity score can be used to assess the patient’s condition and determine if hospitalization is necessary. Patients with additional health conditions usually recover better in a hospital setting. The recommended treatment duration is 5 to 7 days, and signs of improvement include slower breathing, slower heart rate, normal blood pressure, and no fever for more than 48 hours. The therapy recommended depends on whether the patient is an outpatient, in-hospital non-ICU patient, or in-hospital ICU patient. All hospitalized patients who test positive for the influenza virus must be treated with oseltamivir. Once the specific cause of pneumonia is identified, appropriate therapy can be started.
What else can Pneumonia be?
When doctors are examining a patient for respiratory issues, there are numerous conditions they might possibly be facing. These include but are not limited to issues like:
- Asthma
- Reactive airway disease (another term for asthma)
- Viral pneumonia (lung inflammation due to viruses)
- Bacterial pneumonia (lung inflammation due to bacteria)
- Fungal pneumonia (lung inflammation due to fungi)
- Lung abscess (a pus-filled cavity in the lung)
- Bronchiectasis (a condition where the airways in the lungs are damaged and widened)
- Bronchiolitis (inflammation of the small airways)
- Acute and chronic bronchitis (inflammation of the bronchial tubes)
- Atelectasis (a condition where the lung or a part of it collapses)
- Croup (an infection which causes a barking cough)
- Respiratory distress syndrome (breathing problem more common in premature babies)
- Aspiration of a foreign body (when a foreign object gets lodged in the airway)
To make an accurate diagnosis, the doctor will need to carefully consider all of these potential conditions and perform suitable tests.
Possible Complications When Diagnosed with Pneumonia
- Fluid buildup in the lungs
- Infection in the lungs that causes pus collection
- Formation of pus-filled spaces in the lungs
- Widespread infection in the body affecting various organs
- Bacteria spreading in the blood
