The term pneumonia indicates the state of inflammation of the tissue of one or both lungs. It is commonly caused by a "bacterial infection but can also be caused by viruses, fungi, or aspiration of a foreign body."
At the end of the bronchi, "tubes" that carry the air introduced through the nose and mouth to the lungs, there are small bags full of air arranged in clusters called pulmonary alveoli. The alveoli allow the exchange of gases between air and blood (oxygenation of the blood). In pneumonia, the alveoli become inflamed and filled with fluid, making breathing difficult and the exchange of air with blood impossible.
The symptoms (symptoms) caused by pneumonia may appear suddenly, over 24 to 48 hours, or may come on more slowly over several days.
Pneumonia is widespread throughout the world, and is very common in developing countries.
Some categories of people are particularly at risk of getting pneumonia:
- infants or very young children
- elderly people
- people with asthma, cystic fibrosis or with heart, kidney or liver disease
- people with a weakened defense system (immune system), for example, from a recent illness (such as the flu), from the human immunodeficiency virus (HIV), from AIDS or undergoing chemotherapy for the treatment of tumors or being treated with drugs that lower the immune defenses following an organ transplant
The family doctor can ascertain (diagnose) the presence of pneumonia based on the complaints (symptoms) reported by the sick person and on listening (auscultation) of the chest. In some cases, he can prescribe other tests. The diagnosis of pneumonia, in fact, it can sometimes be difficult because some symptoms may be similar to those of other diseases such as the common cold, bronchitis or asthma.
The most common symptoms caused by pneumonia are:
- cough, which may be dry or produce thick, greenish-yellow, brown, or clear mucous phlegm, sometimes streaked with blood
- breathing difficulties, breathing can be rapid and shallow and can give the sensation of "shortness of breath" as during physical exertion
- rapid heartbeat
- generic sense of malaise
- sweating and chills
- loss of appetite
- chest pains, which get worse with breathing or with the effort of coughing
More rarely, coughing up blood may occur (hemoptysis).
In the presence of one or more of these symptoms, a visit to the family doctor is recommended. The doctor may listen to the chest with the stethoscope (auscultation) to detect noises that are not produced in healthy lungs. During breathing, in fact, the air that arrives in areas of the lung filled with fluid due to pneumonia generates particular noises. If the pneumonia appears severe, or if the symptoms do not improve after 48 hours from the beginning of the treatment, it is necessary usually do an x-ray of the lungs as well as additional tests such as sputum (sputum) microbiology and / or blood tests.
If more serious symptoms are present, such as rapid breathing, chest pains or disorientation, it is preferable to go directly to an emergency room.
Pneumonia occurs more frequently in the cold months, it can present in a more severe form in some categories of people such as the elderly or very young children.
Pneumonia is usually caused by a bacterium, lo streptococcus pneumoniae, also known as pneumococcus. Other bacteria can also cause pneumonia, such as haemophilus influenzae, the staphylococcus aureus, the legionella pneumophila.
In addition to pneumonia of bacterial origin, there are also other forms:
- viral pneumonia, most commonly caused by respiratory syncytial virus (RSV) especially in children less than one year of age. It appears as a "bronchiolitis" affecting the smaller bronchi. Other causes of viral pneumonia are influenza A or B viruses and coronaviruses
- aspiration pneumonia, caused by aspiration into the lungs of vomit, foreign objects, toxic substances (such as smoke or chemicals)
- fungal pneumonia, rare, usually affects people with weakened immune systems
- hospital pneumonia (or nosocomial), occurs during the hospitalization of people treated for other diseases or undergoing surgery. Individuals hospitalized in intensive care and undergoing artificial respiration (mechanical ventilation) are particularly at risk. Hospital pneumonia is caused by several bacteria, most notably: pseudomonas aeruginosa, acinetobacter, kebsiella pneumoniae
Non-severe pneumonia can be treated at home, always under the supervision of the family doctor. Bacterial pneumonia is treated with suitable antibiotics, prescribed by the doctor. Getting plenty of rest and drinking plenty of fluids can also help.
In the absence of other diseases, these indications are generally sufficient to lead to recovery, although the cough may last for some time after the other symptoms have disappeared.
Bacterial pneumonia is not normally contagious and there is no risk to the sick person's family members. However, it is advisable that individuals with weak immune systems (due to age, an already existing disease, etc.), avoid direct contact with the sick person.
Hospitalization may be advisable for people considered at risk (the elderly, small children, etc.) because pneumonia could cause them serious and even fatal complications.
In general, bacterial pneumonia is not spread from person to person. However, it is good to follow basic hygiene practices to prevent the transmission of germs:
- cover your mouth and nose when coughing or sneezing
- throw away used tissues immediately because germs can survive for several hours outside the body
- wash your hands regularly to avoid the transfer of germs to other people or objects
A healthy lifestyle can also help prevent pneumonia. For example, smoking damages the lungs and can increase the chance of getting sick.
Similarly, excessive and prolonged use of alcohol contributes to weakening the lung's natural defenses against infection, making it more vulnerable to pneumonia.
People at risk should be encouraged to prevent pneumococcal vaccination (indicated for both young children and the elderly and for people of all ages at high risk) and flu shots.
Pneumonia can create complications in very young children, the elderly, or people with diseases such as diabetes.
Among the most common complications:
- septicemia, occurs when the bacteria responsible for pneumonia are able to pass into the blood, causing a "generalized severe infection to the whole body"
- pleurisy, appears when the thin membrane (pleura) that lines the lungs and the inner wall of the chest becomes inflamed and can cause "respiratory failure
- lung abscess, a rare complication of pneumonia, which can occur in people with other serious illnesses or with a history of alcoholism