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Johns Hopkins Symptoms and Remedies

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Pneumonia

What is it?

Pneumonia, a general term encompassing many different diseases, is an inflammation of the lungs. Although usually caused by an infectious microorganism, such inflammation may also be caused by the inhalation of irritating gases or particles. The lungs have a complex system of defense: frequent branching and narrowing of the bronchial passages make it difficult for invaders to penetrate the lungs deeply; millions of tiny hairs, or cilia, in the bronchial lining constantly sweep particles out of the airways; the cough reflex forces irritating substances out of the lungs at high speed; and white blood cells, known as macrophages (scavenger cells), engulf and destroy many infectious agents. Despite these defenses, pneumonia is still common. Inflammation may be limited to the air sacs (alveoli) of the lung (lobar pneumonia) or may occur in patches throughout the lungs, originating in the airways and spreading to the alveoli (bronchopneumonia). An accumulation of fluid in the alveoli may impair transfer of oxygen to the bloodstream. The body's cells may thus become starved of oxygen, and in severe cases respiratory failure may result. Until the development of antibiotics, pneumonia was the number one cause of death in the United States, and recently, strains of the most common cause of bacterial pneumonia (Streptococcus pneumoniae) have emerged that are penicillin resistant. Pneumonia, especially among the elderly or those already weakened by underlying illness, remains among the 10 leading causes of death today. Nevertheless, despite the serious health risks posed by the disease, the outlook for complete recovery is good, especially with early diagnosis and treatment. For the elderly and members of other high-risk groups, a vaccine is available that provides some long-term protection against 23 different strains of S. pneumoniae (which account for 90 percent of cases of pneumococcal pneumonia).

What Causes It?

  • Viral or bacterial infections are the most common causes of pneumonia.
  • Other microorganisms may sometimes cause pneumonia; for example, fungal and parasitic pneumonia commonly affects those with AIDS.
  • Although bacteria are usually inhaled, they may spread to the lungs from elsewhere in the body via the bloodstream.
  • Inhalation of chemical irritants, such as poisonous gases, may lead to pneumonia.
  • Vomit inhaled into the lungs, which may occur when a person loses consciousness, may cause what is known as aspiration pneumonia.
  • Infancy or very old age, smoking, recent surgery, hospitalization, and the use of chemotherapy and other immunosuppressive drugs are risk factors for pneumonia.
  • Other conditions increase the risk both of contracting pneumonia and of encountering more serious complications associated with the disease. These include asthma, chronic bronchitis, poorly controlled diabetes mellitus, AIDS, alcoholism, Hodgkin's disease, leukemia, multiple myeloma, and chronic kidney disease.

Prevention

  • Don't smoke.
  • People at high risk for pneumonia should be immunized against pneumococcal pneumonia. These people include those over age 65; those with heart, lung, or kidney disease, diabetes mellitus, or weakened immune systems; and alcoholics. The vaccine is required only once; it provides long-term protection and is between 60 to 80 percent effective in those whose immune system is functioning normally.
  • An annual flu vaccination (particularly for people over age 65) may be recommended because pneumonia is a common complication of severe influenza.

Diagnosis

  • Patient history and physical examination.
  • Chest x-rays.
  • Blood and sputum cultures.
  • A biopsy of lung tissue may be performed in complicated cases.

How to Treat It

  • Antibiotics are prescribed to treat a bacterial infection and should be taken for the full term prescribed. Stopping the medication too soon may produce a relapse.
  • Antifungal drugs, such as amphotericin B, are prescribed to treat a fungal infection.
  • Antiviral drugs such as meuraminidase inhibitors, ribavirin, acyclovir, and ganciclovir sodium may be effective against some types of viral infection.
  • Your doctor may recommend analgesics to reduce fever and pain. Check with your doctor before taking over-the-counter pain relievers.
  • Take an over-the-counter cough suppressant containing dextromethorphan if you have a persistent dry cough. However, if you are coughing up sputum, suppressing the cough completely may encourage mucus accumulation in the lungs, potentially leading to serious complications.
  • Your doctor may instruct you how to drain mucus from your lungs by assuming various positions that lower your head below your torso (a technique known as postural drainage).
  • Patients who don't have heart or kidney failure should drink at least eight glasses of water a day to loosen lung secretions and make them easier to expel.
  • Rest in bed until fever subsides.
  • Hospitalization may be recommended, especially during the early stages of infection and/or for patients who are elderly, since pneumonia may unexpectedly become severe within hours.
  • Oxygen may be administered through a mask to aid breathing. In severe cases a respirator may be required.
  • Excess fluid in the space surrounding the lungs may be removed by aspiration with a syringe and needle inserted through the chest wall (thoracentesis).

When to Call a Doctor

  • Call a doctor if you develop symptoms of pneumonia, especially a fever above 100°F, shortness of breath even when lying down, or bloody sputum from coughing.
  • EMERGENCY Call an ambulance if you experience difficulty in breathing or if a blue tinge to the lips, nose, or fingernails appears.