The pneumonia is a lung infection caused most often by a virus or a bacterium.
The infection specifically affects the pulmonary alveoli, the tiny, balloon-shaped sacs at the end of the bronchioles (see diagram). It usually affects only one of the 5 lobes of the lung (3 lobes in the right lung and 2 in the left), hence the term lobar pneumonia. When pneumonia also affects the bronchi, it is called bronchopneumonia.
Pneumonia refers to a wide variety of infections that may be minor or life-threatening. Thus, if pneumonia appears as a complication of a serious illness or in an elderly person, it can be fatal. In very rare cases, pneumonia can also be fatal in a healthy person.
The disease usually manifests as a cough, often accompanied by sputum, shortness of breath, fever and chills. Pneumonia is most often caught as an influenza or cold by inhaling contaminated particles. In some cases, it occurs after another respiratory infection, such as influenza or bronchitis, which “degenerates” and settles in the alveoli of the lungs. Some of the symptoms may last for several weeks. It is usually not very contagious.
|The term pneumonitis is sometimes used as a synonym for pneumonia. In fact, in medical use, pneumonia refers to an infection of the lungs caused by a microbe (virus, bacterium), while pneumonitis is a broader term meaning “lung disease”. There are, for example, forms of lung disease caused not by microbes, but by inhalation of irritants, dusts or prolonged use of tobacco. Their symptoms resemble those of pneumonia.|
Causes of Pneumonia
Almost all pneumonia is caused by a virus or bacteria. When the microbe attacks the lungs, the body reacts by triggering an inflammation reaction. The cells are filled with pus and inflammatory fluid, which leads to breathing difficulties.
The physician must distinguish between two modes of contraction of pneumonia: contraction in hospital (nosocomial pneumonias) and contraction outside hospital (community-acquired or community-acquired pneumonias). The nosocomial pneumonia is generally more dangerousbecause they occur in people weakened by another disease. In hospitals, pneumonia is often transmitted through mechanical ventilation devices (intubation) in intensive care units.
The exact type of bacterium or virus responsible for pneumonia in a given patient is only known in half of the cases,partly because laboratory techniques are not performing well enough. For your information, here are the ones most commonly found in people with pneumonia.
Bacteria. Bacterial infections most commonly cause typical pneumonia (see Symptoms section). Most of the time, Haemophilus influenzae, Staphylococcus aureus or Streptococcus pneumoniae (causing pneumococcal pneumonia) are responsible for this.
The atypical pneumoniais manifested by symptoms that may be less pronounced than typical pneumonia. For example, some people with pneumonia have no fever or chest pain. Pneumonia is then thought of as a respiratory infection, such as bronchitis, sinusitis or influenza (influenza). Bacteria that cause atypical pneumonia include Mycoplasma pneumoniae (causing mycoplasma pneumonia), Chlamydia pneumoniae, and Legionella pneumophila (responsible for Legionnaires’ disease).
Virus . The most common are influenza and parainfluenza viruses, respiratory syncytial virus, cold viruses (rhinovirus), herpes virus or SARS virus. The influenza virus, that is, the flu virus, sometimes reaches the alveoli of the lungs and causes viral pneumonia . Subsequently, the respiratory tract weakened by viral infection may open the door to potentially more serious bacterial superinfection.
In early 2003, an outbreak of SARS or Severe Acute Respiratory Syndrome ( SARS) caused casualties in several countries. China, Singapore and Canada (especially the City of Toronto) were the hardest hit. In total, more than 8,000 people became infected with SARS. Of these, 800 died, including 43 in Canada. The epidemic could be controlled within 4 months thanks to measures to prevent its transmission (masks, quarantine, etc.). SARS is caused by a highly contagious coronavirus.
Other rarer causes of pneumonia
- The aspiration pneumonia occurs when some of the liquid in the stomach is aspirated into lungs. The bacteria present in this liquid then reach the bronchi and pulmonary alveoli and cause an infection. This phenomenon usually occurs after anesthesia or as a result of a neurological disorder affecting the swallowing reflex or if inhaling its vomiting, due to overuse of alcohol or drugs.
- Inhalation of certain toxic products (kerosene, varnishes, paint thinners, etc.) or mold (during construction work, mainly in people whose immune system is weakened by immunosuppressive treatment), or allergy to workplace products can cause lung inflammation and bleeding. These conditions increase the risk of pneumonia and may cause pneumonitis , an inflammation of the lungs, of non-infectious origin.
- Tuberculosis may be in the form of pneumonia.
- Pneumonia caused by a parasite or fungus is especially common in people whose immune systems are weakened. Pulmonary aspergillosis is an example, as is pneumocystosis (caused by a parasite).
According to the Quebec Lung Association, 200,000 to 300,000 Canadians have pneumonia each year and the mortality rate can reach 30% in some populations (elderly, hospitalized …). The acquired pneumonia in hospital affects 0.5% to 1% of hospitalized patients, but up to 40% of mechanical ventilation in intensive care.
Diagnostic of Pneumonia
The doctor evaluates the symptoms , inquires about the family history and examines the lungs. He can administer a radiological examination of the lungs and request an analysis of pulmonary secretions (expelled by coughing). If necessary, he will use other tests, for example the search for bacteria in the blood.
Pneumonia can be cured most of the time in 2 weeks or more. However, more time is often needed before recovering completely.
Although rare, some serious complications are possible.
- A pleural effusion . It is the accumulation of inflammation fluid between the two layers of the pleura , which causes a compression of the lung. If there is a lot of liquid, it must be removed by suction. Exceptionally, it happens that this liquid persists and becomes purulent. Surgery is often necessary.
- An abscess to the lung.
- A respiratory distress . When pneumonia affects both lungs, breathing becomes extremely difficult. Ventilation is often necessary.
- A septic shock , that is to say a generalized infection of the body due to the passage of bacteria from the lungs to the blood. This occurs mostly with pneumococcal pneumonia.
Thanks to antibiotics, pneumonia causes far fewer deaths than before. All the same, pneumonia and influenza (influenza) together make up the leading cause of death from an infectious disease in Canada . The very elderly , whose immune system is weaker, and people with other serious illness are more likely to succumb to it.
The symptoms of pneumonia
- A sudden fever rise of up to 41ºC (106ºF) and heavy chills.
- Shortness of breath, rapid breathing and pulse.
- A cough. At first, the cough is dry. After a few days, it becomes greasy and is accompanied by yellowish or greenish secretions, sometimes streaked with blood.
- Chest pain that intensifies during coughing and deep breaths.
- A deterioration of the general state (fatigue, loss of appetite).
- Muscular pain.
Some signs of seriousness should lead to immediate hospitalization.
- Alteration of consciousness.
- Pulse too fast (greater than 120 beats per minute) or breathing rate greater than 30 breaths per minute.
- Temperature above 40 ° C (104 ° F) or below 35 ° C (95 ° F).
“Atypical” pneumonias are more misleading because their symptoms are less specific. They can manifest themselves as headaches , digestive disorders or joint pains . Cough is present in 80% of cases, but in only 60% of cases in the elderly.
People at risk
- The children . The risk increases further in those exposed to second-hand smoke.
- Older people , especially if they live in retirement homes.
- People with chronic respiratory illness (asthma, emphysema, COPD, bronchitis, cystic fibrosis).
- People with a chronic disease that weakens the immune system , such as HIV / AIDS, cancer, or diabetes.
- People who receive immunosuppressive therapy or corticosteroid therapy are also at risk for opportunistic pneumonia .
- People who have just had a respiratory infection , such as the flu.
- People hospitalized , particularly in an intensive care unit.
- People exposed to toxic chemicals in the course of their work (for example, varnishes or paint thinners), bird breeders, and workers in the making or processing of wool, malt and cheese.
- Aboriginal populations in Canada and Alaska are at increased risk of pneumococcal pneumonia.
- Smoking and exposure to second-hand smoke
- Alcohol abuse
- Drug use
- Unhealthy and overcrowded housing
Prevention of pneumonia
|Basic preventive measures|
|Other measures to prevent the onset of the disease|
|Measures to promote healing and prevent aggravation|
|First of all, it is important to respect a period of rest.
Throughout the illness, avoid exposure to smoke, cold air and air pollutants as much as possible.
|Measures to prevent complications|
|If the symptoms of pneumonia persist with the same intensity 3 days after the beginning of an antibiotic treatment, you must see your doctor as soon as possible.
Medical treatments for pneumonia
Treatment depends primarily on the cause of pneumonia (bacteria, viruses, fungus …). To choose the appropriate treatment, the doctor also bases on the age, the state of health and a physical examination of the person and, if necessary, on various complementary analyzes.
Treatment at home
Bacterial pneumonia . In healthy people, most community-acquired pneumonias are treated with a macrolide antibiotic (erythromycin, clarithromycin, azithromycin). There is usually no reason to go to the hospital.
|The bacteria responsible for pneumonia are increasingly resistant to antibiotics. The phenomenon is particularly worrying in the case of pneumonia acquired at the hospital. If the antibiotic does not seem to be effective after a few days, it may be necessary to change the antibiotic. To avoid contributing to resistance, it is important to take your treatment to the end, as prescribed by your doctor.|
Viral pneumonia . Most of the time, viral pneumonia heals without treatment. Antibiotics are not effective against viruses. In some cases, antiviral drugs may be used, such as oseltamivir (Tamiflu) or zanamivir (Relenza). If necessary, other medications will help relieve chest pain and lower fever (paracetamol, also called acetaminophen, and more rarely ibuprofen rather recommended in Quebec).
Regarding cough , it should not be completely eliminated since it helps to expel the secretions that clog the bronchi. Cough syrups are also generally discouraged by doctors. To relieve coughs and sore throats, natural solutions, such as drinking hot water with a little honey, are preferable.
Respiratory physiotherapy. This technique, especially used in people with chronic respiratory disease, can help clear the airways. In Quebec, respiratory therapists teach it to patients. Percussion movements are performed on the patient’s back, triggering coughing and clearing secretions. The person should be lying on their stomach, their upper body tilted down. Respiratory physiotherapy seems to help shorten healing time and prevent complications.
|Followed . A visit to the doctor 4 to 6 weeks after the diagnosis and a chest x-ray will help to ensure that the pneumonia is well healed. If she does not recover within the usual time, the doctor will recommend an appropriate investigation, such as a CT scan or bronchoscopy . Persistent pneumonia can be caused by a tumor in a bronchus.|
Treatment at the hospital
When pneumonia is severe or the risk of complications is high, hospitalization may be necessary. We can then administer drugs intravenously or provide oxygen if we find that the blood oxygen level is too low. Most people hospitalized for pneumonia are babies, young children, the elderly, or people with weakened and chronically ill people.
| For a better comfort
· The sitting position is the most comfortable. In the horizontal, the breathing is more laborious. At night, opt for a slightly inclined position. Elevate the back with pillows.