Pneumonia

Pneumonia is an infection of the lungs.

Causes

Pneumonia affects the lower respiratory tract (small bronchi and air sacs in the lungs). There are three main causes:
Bacterial Pneumonia – caused by bacteria, most commonly Streptococcus pneumoniae. Tuberculosis is a chronic bacterial pneumonia common throughout the world.
Viral Pneumonia – caused by a virus. Viruses cause half of all pneumonias.
Mycoplasma (Walking) Pneumonia – caused by mycoplasmas, tiny disease agents that have traits of both bacteria and viruses. This type of pneumonia is often milder.
Other causes of pneumonia include:
  • Fungal infections, such as Pneumocystis cariniipneumonia (PCP) – a fungal infection common in people with AIDS
  • Pneumonitis – inflammation of the lungs caused by inhaled chemicals, food, liquids, or foreign objects (can lead to an infectious pneumonia)

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.
  • Age: 65 or older
  • Flu or other respiratory illness
  • Chronic illness, such as heart or lung disease
  • Stroke (aspiration pneumonia due to difficult swallowing)
  • Weakened immune system caused by AIDS or chemotherapy treatment
  • Chronic bronchitis
  • Malnutrition
  • Alcohol or drug abuse
  • Smoking
  • Chronic exposure to certain chemicals (e.g., work in construction or agriculture)

Symptoms

Symptoms of Pneumonia may include some or all of the following: Bacterial PneumoniaViral PneumoniaMycoplasmal PneumoniaFeverFeverFever, often low-gradeShaking chillsChillsChillsCough that produces green, yellow, or rust-colored mucusDry coughCoughing; may be violent at times; produces white mucusChest painHeadachePossible nausea or vomitingProfuse sweatingMuscle painWeaknessBluish color of the nails or lips due to diminished oxygen in the bloodBluish color of the nails or lips due to diminished oxygen in the bloodConfused mental stateWeakness

Diagnosis

The doctor will ask about your symptoms and medical history, and perform a physical exam. Diagnosis of Pneumonia is based on symptoms and listening to your chest with a stethoscope. In addition, tests may include:
  • Chest x-ray
  • CT scan – a type of x-ray that uses a computer to make pictures of structures inside the chest
  • Blood tests
  • Bronchoscopy – direct examination of airways
  • Sputum culture – testing mucus coughed up from deep in the lungs
  • Pulse oximetry – measures the amount of oxygen in the blood
  • Arterial blood gas – measures oxygen, carbon dioxide and acid in the blood

Treatment

Treatment of Pneumonia depends on:
  • The type of pneumonia
  • Severity of symptoms
  • Other factors
Common methods of treatment include: Bacterial Pneumonia
Antibiotics.
Viral Pneumonia
  • Rest and fluids
  • Antiviral medicines - may be prescribed for young children and patients with weakened immune systems (Note: Antibiotics are ineffective for treating viral pneumonia.)
Mycoplasma Pneumonia
Usually treated with antibiotics.
General
  • Over-the-counter medicines to reduce fever and aches, and soothe cough
  • Hospitalization, for people with very severe symptoms
It is very important to take medicine exactly as prescribed. Stopping medicine midway may cause a relapse, or create a strain of bacteria resistant to drug treatment.

Prevention

Certain vaccines can help prevent Pneumonia:
Flu Shot – for people at high risk, particularly the elderly, because pneumonia may be a complication of the flu
Pneumococcal Vaccine - recommended for people over age 65, or those who have a chronic illness, such as diabetes or sickle-cell disease
Other preventive measures include:
  • Avoid smoking. Smoking weakens the lungs' resistance to infection.
  • Avoid close contact with people who have respiratory infections.
  • Wash hands often when coming in contact with infected people.
  • Protect yourself from job exposures that affect the lungs.
  • Eat a healthy diet.
  • Get adequate rest.
  • Exercise regularly.