Pneumonia is a serious infection or inflammation of one or both lungs.

Pneumonia is caused by the inhalation of infected microorganisms (tiny, single-celled living organisms, such as bacteria, viruses, fungi or protozoa) spread through contact with an infected person. The microorganisms enter the body through the mouth, nose and eyes. If the body’s resistance is down, the natural process of fighting off diseases is weakened and the microorganisms are free to spread into the lungs and the lungs’ air sacs. The air sacs become filled with fluid and pus from the infectious agent, making it more difficult for the body to get the oxygen it needs, and the person may become sick.

Potential complications of pneumonia include pleural effusion (fluid around the lung), empyema (pus in the pleural cavity), hyponatremia (low blood sodium) and rarely, an abscess in the lung.

Causes and Risk Factors of Pneumonia

There are over 30 different causes of pneumonia, but the most common causes are bacteria (including mycoplasma) and viruses. Corresponding to these causes are the most common types of pneumonia – bacterial pneumonia, viral pneumonia and mycoplasma pneumonia.’

Bacterial pneumonia

Pneumonia-causing bacteria is present in many throats, but when the body’s defenses are weakened (for example, by illness, old age, malnutrition or impaired immunity) the bacteria can multiply, working its way into the lungs, inflaming the air sacs and filling the lungs with liquid and pus. The bacteria that cause bacterial pneumonia are streptococcus pneumonia (resulting in lobar pneumonia), hemophilus influenza (resulting in bronchopneumonia), legionella pneumophilia (resulting in Legionnaires’ disease) and staphylococcus aureus.

Viral pneumonia

Half of all pneumonias are believed to be caused by viruses, such as influenza (flu), adenovirus, coxsackievirus, chickenpox, measles, cytomegalovirus and respiratory syncytial virus. These viruses invade the lungs and multiply.

Mycoplasmal pneumonia (also called “walking pneumonia”)

Similar to bacterial pneumonia, the mycoplasmas multiply and spread, causing infection.

Some of the other pneumonia-related disorders are aspiration pneumonia, chlamydial pneumonia, Loffler’s syndrome, pneumocystis carinii pneumonia, pediatric pneumonia and necrotizing pneumonia.

Risk factors include:

  • 65 years of age or older
  • People in nursing homes or other chronic care facilities
  • Male
  • Children under the age of two
  • People with colds or other respiratory infections
  • People with reduced immunity
  • People with other lung diseases, such as asthma, cystic fibrosis and lung cancer
  • People with AIDS or HIV
  • Organ transplant recipients
  • People who have had their spleen removed
  • People receiving chemotherapy
  • People who smoke
  • Alcoholics
  • People with chronic health problems, such as lung disease, heart disease, kidney disorders, sickle cell anemia or diabetes

Symptoms of Pneumonia

Symptoms vary, depending on the type of pneumonia and the individual.

With bacterial pneumonia, the person may experience:

  • shaking
  • chills
  • chattering teeth
  • severe chest pain
  • cough that produces rust-colored or greenish mucus
  • very high fever
  • sweating
  • rapid breathing
  • rapid pulse rate

With viral pneumonia, the person may experience:

  • fever
  • dry cough
  • headache
  • muscle pain and weakness

These flu-like symptoms may be followed within one or two days by:

  • increasing breathlessness
  • dry cough becomes worse and produces a small amount of mucus
  • higher fever
  • bluish color to the lips

With mycoplasma pneumonia, the person may experience:

  • violent coughing attacks
  • chills
  • fever
  • nausea
  • vomiting
  • slow heartbeat
  • breathlessness
  • bluish color to lips and nailbeds
  • diarrhea
  • rash
  • muscle aches

Regardless of the type of pneumonia, the person may also experience the following symptoms:

  • a loss in appetite
  • feeling ill
  • clammy skin
  • nasal flaring
  • fatigue
  • mental confusion
  • joint and muscle stiffness
  • anxiety, stress and tension
  • abdominal pain

Diagnosis of Pneumonia

To diagnose pneumonia, the doctor begins with a medical history and physical examination. By placing a stethoscope on the chest, the doctor may be able to hear crackling sounds, coarse breathing, wheezing and/or the breathing may be faint in a particular area of the chest. Additionally, the doctor may order a chest x-ray, a sputum gram stain and a blood test. The chest x-ray may show a blotchy-white area, where fluid and pus has accumulated in the lung’s air sacs. The sputum grain stain and the blood test may determine the cause and severity of the condition.

If these tests are inconclusive, the doctor may perform a procedure called a bronchoscopy. In this procedure, a flexible, thin and lit viewing tube is inserted into the nose or mouth after a local anesthetic is administered. The breathing passages can then be directly examined by the doctor and specimens from the infected part of the lung can be obtained.

Treatment of Pneumonia

Treatment depends on the severity of symptoms and the type of organism causing the infection.

Bacterial pneumonia (caused by the streptococcus pneumonia bacteria) is often treated with penicillin, ampicillin-clavulanate (Augmentin) and erythromycin. Bacterial pneumonia (caused by the hemophilus influenza bacteria) is treated with antibiotics, such as cefuroxime (Ceftin), ampicillin-clavulanate (Augmentin), ofloxacin (Floxin), and trimethoprim-sulfanethoxazole (Bactrim and Septra). Bacterial pneumonia (caused by legionella pneumophilia and staphylococcus aureus bacteria) are treated with antibiotics, such as erythromycin.

Viral pneumonia does not respond to antibiotic treatment. This type of pneumonia usually resolves over time. If the lungs become infected with a secondary bacterial infection, the doctor will prescribe an appropriate antibiotic to eliminate the bacterial infection.

Mycoplasma pneumonia is often treated with antibiotics, such as erythromycin, clarithromycin (Biaxin), tetracycline or azithromycin (Zithromax).

In addition to the pharmaceutical intervention, the doctor will also recommend bedrest, plenty of fluids, therapeutic coughing, breathing exercises, proper diet, cough suppressants, pain relievers and fever reducers, such as aspirin (not for children) or acetaminophen. In severe cases, oxygen therapy and artificial ventilation may be required.

The course of pneumonia varies. Recovery time depends upon the organism involved, the general health of the person and how promptly medical attention was obtained. A majority of sufferers recover completely within a few weeks, with residual coughing persisting between six and eight weeks after the infection has gone.

Prevention of Pneumonia

  • Practice good hygiene.
  • Get an influenza shot each fall.
  • Get a pneumonococcal vaccine. People who stand to benefit most from vaccination are those over the age 65; anyone with chronic health problems (such as diabetes, kidney disease, heart disease, etc.); anyone who has had their spleen removed; anyone living in a nursing home or chronic care facility; caregivers of the chronically ill (healthcare workers or family caregivers); children with chronic respiratory diseases (such as asthma), and anyone who has had pneumonia in the past (due to increased risk of reinfection). The pneumonococcal vaccine is 90 percent effective against the bacteria and protects against infection for five to 10 years.
  • Practice good preventive measures by eating a proper diet, getting regular exercise and plenty of sleep.
  • Do not smoke.

Questions To Ask Your Doctor About Pneumonia

Are tests needed to diagnose or determine the cause of this pneumonia?

  • What is the cause?
  • How serious is the condition?
  • What treatment do you recommend?
  • How long until full recovery?
  • Can pneumonia recur more frequently?
  • Do you recommend a vaccination?