Pneumonia

Overview

Pneumonia is an infection that affects the air sacs in one or both lungs. These air sacs may fill with fluid or inflammatory material, making it harder for oxygen to pass into the bloodstream. Pneumonia can range from mild to severe, depending on the cause of the infection, the person’s age, general health, and how quickly treatment is started.

Pneumonia may be caused by different types of germs, including bacteria, viruses, and fungi. It can develop in otherwise healthy people, but it is more likely to cause complications in babies, older adults, people with long-term medical conditions, and people with weakened immune systems.

With appropriate medical assessment and care, many people recover well. However, pneumonia should be taken seriously because it can sometimes progress quickly or lead to breathing problems, especially in higher-risk patients.

Symptoms

The symptoms of pneumonia can vary from person to person. Some people develop symptoms suddenly, while others notice a gradual worsening over several days. Symptoms may also be less typical in older adults or people with chronic illnesses.

• Cough, which may produce mucus or phlegm
• Fever, chills, or sweating
• Shortness of breath or faster breathing
• Chest pain that may worsen with coughing or deep breathing
• Tiredness, weakness, or loss of energy
• Loss of appetite
• Headache or body aches
• Nausea, vomiting, or diarrhea in some cases
• Confusion or unusual sleepiness, especially in older adults

In infants and young children, signs may include poor feeding, irritability, unusual sleepiness, fever, breathing difficulty, or bluish coloring around the lips. Any breathing difficulty in a child should be assessed promptly by a healthcare professional.

Causes and Risk Factors

Pneumonia occurs when germs enter the lungs and cause infection and inflammation. The body’s immune system responds to the infection, which can lead to swelling and fluid buildup in the air sacs.

Common causes include bacterial infections, viral respiratory infections, and, less commonly, fungal infections. Pneumonia may develop after a cold, flu-like illness, or another respiratory infection. It may also occur when food, saliva, vomit, or fluids are inhaled into the lungs, which is known as aspiration pneumonia.

Several factors can increase the risk of developing pneumonia or having more severe illness:

• Older age or very young age
• Smoking or exposure to heavy air pollution
• Chronic lung diseases such as asthma or chronic obstructive pulmonary disease
• Heart disease, diabetes, kidney disease, or other long-term conditions
• A weakened immune system due to illness or medical treatment
• Recent surgery or prolonged bed rest
• Difficulty swallowing or conditions that increase the risk of aspiration
• Recent respiratory infection

Diagnosis

A healthcare professional evaluates possible pneumonia by reviewing symptoms, medical history, and risk factors, followed by a physical examination. During the examination, the chest is usually listened to with a stethoscope to check for abnormal breath sounds.

Tests may be recommended depending on the person’s age, symptoms, and overall condition. A chest X-ray is commonly used to look for signs of infection in the lungs. Blood tests may help assess infection and the body’s response. In some cases, a mucus sample may be tested to help identify the cause. Measurement of oxygen levels may also be performed, especially if there is shortness of breath or concern about low oxygen.

Some patients may need more detailed imaging or hospital-based evaluation, particularly if symptoms are severe, if there are other medical conditions, or if the diagnosis is uncertain.

Treatment Options

Treatment for pneumonia depends on the suspected cause, severity of illness, age, and underlying health conditions. The main goals are to control the infection, support breathing, prevent complications, and help the body recover.

If pneumonia is thought to be bacterial, a doctor may prescribe antibiotic treatment. Viral pneumonia is managed differently, and treatment focuses on supportive care and, in selected cases, specific antiviral treatment when appropriate. Fungal pneumonia requires specialized medical evaluation and treatment.

Supportive care may include fluids, rest, fever control, and monitoring of breathing. Some patients may need oxygen therapy if oxygen levels are low. Hospital care may be recommended for people with severe symptoms, low oxygen levels, dehydration, confusion, significant underlying disease, or increased risk of complications.

Recovery time varies. Cough and tiredness may last for some time after the infection begins to improve. Follow-up appointments may be advised to ensure recovery is progressing and to reassess symptoms if they continue.

Vaccination against certain respiratory infections may help reduce the risk of some types of pneumonia. A healthcare professional can advise which vaccines are appropriate based on age, medical history, and travel or occupational factors.

When to See a Doctor

Medical assessment is important if pneumonia is suspected, especially when symptoms are worsening or not improving. Early evaluation helps determine the cause and the most appropriate care.

Seek medical attention promptly if any of the following occur:

• Shortness of breath, rapid breathing, or difficulty breathing
• Chest pain, especially with breathing or coughing
• Persistent high fever or chills
• Cough with worsening mucus or blood in the mucus
• Confusion, fainting, or unusual drowsiness
• Bluish lips or fingertips
• Symptoms in an infant, older adult, pregnant person, or someone with a weakened immune system
• Worsening symptoms despite medical advice or previous treatment

Pneumonia can be serious, but timely medical care can help reduce the risk of complications. Anyone concerned about breathing symptoms should contact a qualified healthcare professional for evaluation.