Pneumonia

Pneumonia is a serious illness that predominantly threatens children, the elderly and people with a chronic obstructive lung disease. Some 200 000 to 300 000 Canadians develop pneumonia each year, and in certain population groups the mortality rate can be as high as 30% among its victims.

Definition

Pneumonia is an infectious disease caused by a bacteria or virus; as the lungs become inflamed, pus, secretions and liquids build up in the pulmonary alveoli, which weakens the distribution of oxygen to the blood. When blood oxygen levels drop too severely, cells cease functioning normally and they can even die.

Pneumonia cases are very common. The onset of pneumonia symptoms is often brutally swift, thus surprising the otherwise healthy victim. Most people are cured within two weeks. Pneumonia ranks sixth among the causes of death in industrialized countries like ours.

Pneumonia affects the lungs

1. Lobar pneumonia affects an area of the lung : the lobe

2. Bronchial pneumonia (or bronchopneumonia) affects the bronchioles and pulmonary alveoli.

Those who are most vulnerable

Children, the elderly, the chronically ill, victims of a respiratory condition and people suffering from a viral infection are more likely to develop pneumonia.

The causes of pneumonia

Pneumonia is a complex disease that may be caused by over 30 different factors. There are three forms of pneumonia, each with its own causal agent :

• bacteria
• viruses
• mycoplasmas

Bacterial pneumonia

Bacterial pneumonia can affect people of all ages. Most vulnerable are alcoholics, severely weakened individuals, post-operative patients and people with respiratory diseases or viral infections.

The pneumococcus bacterium is the most common cause of bacterial pneumonia, the only form of pneumonia for which there exists a specific vaccine, i.e. the pneumococcal vaccine.

Everyone has these bacteria. When the body’s resistance is depleted by certain factors (disease, aging, malnutrition, extensive weakness), these bacteria multiply, invade the lungs and cause the alveoli to become inflamed. Liquids begin to build up in the tissues of a lobe section, an entire lobe or all the lobes of a lung. The infection then spreads to the whole body through the bloodstream.

Symptoms

The first symptoms of bacterial pneumonia may appear suddenly or gradually. These symptoms include :

• Fever, chills and chattering teeth.
• The body’s temperature may rise to 40.5ºC.
• Acute chest pains and coughing that produces rustcoloured or greenish mucus.
• Profuse sweating, accelerated respiration and pulse.
• Lips and nailbeds may develop a bluish colour due to lack of oxygen in the blood.
• Confusion and even delirium in certain cases.

Viral pneumonia

Half of all pneumonias are due to viruses. Viruses often cause respiratory infections that mainly affect the upper respiratory tract. Certain viruses however target the lungs and produce pneumonia, especially in children. Most viral pneumonias are localized and do not tend to spread but the primitive form of viral pneumonia caused by the influenza virus (flu virus) is severe and occasionally fatal. The virus invades the lungs and multiplies without producing observable symptoms. Victims of this form of pneumonia are mostly pregnant women or individuals with cardiovascular conditions or respiratory diseases.

Symptoms

The symptoms of viral pneumonia are similar to those of the flu :

• Fever, dry cough, headaches, muscle pain and weakness.

Twelve to thirty-six hours (12 to 36 hours) after the onset of these symptoms, victims experience severe breathlessness. The cough becomes worse and limited amounts of mucus produced contain traces of blood. There is a high fever and blueness of the lips. In the final stage, the victim is suffocating and struggles desperately to breathe. Some viral pneumonias may be complicated by a bacterial attack characterized by all the symptoms of the latter.

Mycoplasma pneumonia

Mycoplasma pneumonia used to be referred to as "primary atypical pneumonia" because it was believed to be caused by one or several undiscovered viruses. It is actually caused by pathogenic microorganisms that are smaller than the bacteria and viruses discovered and identified during World War II. The progression and symptoms of mycoplasma pneumonia are significantly different from those of pneumococcal pneumonias. This mild and widespread form of pneumonia occurs predominantly in older children and adolescents.

Symptoms

Mycoplasma pneumonia is characterized by :

• severe cough attacks,
• chills and fever that may or may not be accompanied by nausea and vomiting,
• occasional observation of reduced heart rate.

Other kinds of pneumonia

Some specific kinds of pneumonia may be caused by the inhalation of foods, liquids, gases or dust; they can also occur as a result of a foreign body or bronchial obstruction such as a tumor. "Rickettsia", microorganisms somewhere between bacteria and viruses, cause Rocky Mountain spotted fever, typhus and psittacosis. These diseases produce more or less severe effects on the lungs. Finally, tuberculosis pneumonia can cause very serious pulmonary lesions unless treated early.

Tests performed following possible diagnosis of pneumonia

• Patient’s medical history
• Chest X-ray
• Blood analyses
• Physical examination

Treating pneumonia

There exists a variety of elements or germs that can cause pneumonia; however, certain factors like age, early diagnosis, type of infection and absence or presence of another disease influence recovery.

The physician prescribes drugs based on the germ that caused the pneumonia. Antibiotics are suitably prescribed. Drugs reduce the fever in a day or two and quickly relieve the other symptoms. Treatment of pneumonia may also include a diet, inhalation therapy to relieve suffocation and restore lip coloration. Drugs are also taken to ease chest pains and relieve coughing if necessary.

Is pneumonia contagious?

Most types of pneumonia are transmitted in the same way as influenza or the common cold : by people's hands and by tiny droplets from their mouths and noses. In fact, the same viruses that cause colds and the flu can also cause pneumonia. If the viruses infect the throat, sinus or upper respiratory airway, they cause a cold or the flu. If a virus reaches the lungs, it can cause pneumonia.

Young children, people over 65, those suffering from a chronic illness or with an immune system deficiency, have higher risk of pneumonia.

Recovery

One should never presume to have recovered from pneumonia, as relapses are possible and far more serious than the disease itself. The symptoms of pneumonia in elderly individuals are much more persistent than they are in young people. Recovery takes approximately 7 to 10 days, but it may require more time in some cases. A series of follow-up X-rays are needed to ascertain recovery.

Preventing pneumonia

Preventing pneumonia is increasingly important given the aggressive nature of this disease. There is a vaccine against pneumococcal pneumonia : it is called "pneumovax".

Individuals who are especially vulnerable to pneumococcal infection and who should receive this vaccine, are found in the following groups :

• people who are 65 or more.

Other high-risk groups include adults and children over the age of two, whose history includes one of the following factors :

• chronic heart, lung or kidney disease,
• diabetes, alcoholism, absence of spleen or dysfunctional spleen,
• certain forms of anemia,
• people recovering from a severe illness,
• HIV infection or other diseases linked to an immune system deficiency,
• people living in a hospital center for long-term care.

Some people should not receive the pneumococcal vaccine: pregnant women, nursing mothers and children under age two.

It is also important to consult a doctor if a respiratory infection lasts more than a few days. Pneumonia is often traced back to such infections.

If you have symptoms of pneumonia

1. Consult a physician immediately; early diagnosis and treatment promote recovery.
2. Follow your doctor’s advice. If your treatment is to be successful, it is crucial that you get plenty of rest and take all the medicine prescribed.
3. Be patient. Pneumonia is a serious illness. Improve your chances of recovery.

Prevention is elementary, so getting a flu shot every year is a good idea. We also recommend that individuals who are at high risk arrange to receive the pneumococcal vaccine as recommended by their doctor.