Pneumonia

Overview

Pneumonia is an infection that inflames the air sacs in one or both lungs. These air sacs may fill with fluid or pus, causing cough, fever, chills, and difficulty breathing. It can be caused by bacteria, viruses, fungi, or, less commonly, by inhalation of harmful substances. Pneumonia remains a leading cause of hospitalization worldwide, affecting all age groups but posing the greatest risk to infants, older adults, and people with weakened immune systems.

Causes

Bacterial pneumonia — often caused by Streptococcus pneumoniae.
Viral pneumonia — caused by viruses like influenza, RSV, or SARS-CoV-2.
Fungal pneumonia — common in people with weakened immunity.
Aspiration pneumonia from inhaling food, liquids, or vomit into the lungs.

Symptoms

Cough (may produce green, yellow, or bloody mucus)
Fever, sweating, and chills
Shortness of breath
Chest pain when breathing or coughing
Fatigue and muscle aches
Confusion, especially in older adults

Diagnosis

Diagnosis of pneumonia involves a combination of medical history, physical examination, and diagnostic tests.

Physical exam — doctor listens to lungs for abnormal sounds like crackles or wheezing.
Chest X-ray — confirms presence, location, and extent of lung infection.
Blood tests — check for infection and identify the organism causing it.
Sputum test — analyzes mucus to identify bacteria or viruses.
Pulse oximetry — measures oxygen level in the blood.
CT scan or bronchoscopy in complicated or unclear cases.

Prevention

Get vaccinated (pneumococcal, influenza, COVID-19 vaccines).
Practice good hand hygiene.
Avoid smoking and secondhand smoke.
Maintain a healthy immune system with balanced nutrition and regular exercise.
Wear masks in high-risk environments or during outbreaks.

Treatment

Bacterial pneumonia — treated with antibiotics.
Viral pneumonia — supportive care; antiviral medications in some cases.
Oxygen therapy for severe cases.
Pain relievers and fever reducers (acetaminophen, ibuprofen).
Rest and adequate fluid intake.

Possible Complications

Pleural effusion (fluid around the lungs)
Sepsis
Lung abscess
Respiratory failure

When to Seek Medical Attention

Seek immediate medical care if you have persistent fever, difficulty breathing, chest pain, confusion, or symptoms that worsen after initial improvement.