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4.3. Diseases of the respiratory system

Diseases of the respiratory system

The air we breathe in contains many particles, some of them harmful to the body. It can contain viruses, bacteria, pollen grains, ash, fumes, etc., which can cause illness. Although most respiratory diseases are related to smoking.

The main diseases of the respiratory system are:


The asthma is a disease that causes the bronchi reduce its diameter and hinder the passage of the air.

It is usually caused by genetic inheritance, by infections or by allergies to dust, animal hair or feathers, molds, pollen, etc.

The treatment consists of the administration of bronchodilator substances and avoiding the cause that causes the allergy.

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The tonsillitis is the inflammation of the tonsils caused by an infection viral or bacterial, but could have pus forming plaques.

Tonsils contain cells that produce antibodies useful in fighting infection, so their removal is only recommended in severe cases .

Amigdalitis con placas producidas por bacterias

By Michaelbladon at English Wikipedia (Transferred from en.wikipedia to Commons.) [Public domain], via Wikimedia Commons


The throat is inflammation of the pharynx, produced by irritation, usually caused by infection bacterial or viral. It is usually associated with tonsillitis.


The sinusitis is inflammation of the sinuses, which are cavities of some bones of the face and skull that are connected with the nostrils.

It is caused by fungi, bacteria or a virus, or also by an allergy.

Senos paranasales

By Nnh_front.svg: Own work *translation: Angelito7 (talk)This is a retouched picture, which means that it has been digitally altered from its original version. Modifications: Translation to spanish. The original can be viewed here: Nnh front.svg. Modifications made by Angelito7. (Nnh_front.svg) [Public domain], via Wikimedia Commons

Aphonia and dysphonia

The hoarseness is the complete loss of voice, whereas dysphonia is the partial loss of voice. It is due to infections or overexertion when yelling or talking for a long time. The cold favors its appearance.


The bronchitis is inflammation of the lining of the bronchi. It is caused by a bacterial, viral or irritant infection (pollution, tobacco).

When you have bronchitis, the air has more difficulty to travel, so the bronchial tubes are irritated and more mucus is produced.

The most characteristic symptom of bronchitis is cough, but in severe cases it can be accompanied by sputum, fever and general malaise.


The pneumonia is inflammation of the alveoli caused by an infection caused by bacteria, viruses or fungi. The alveoli fill with pus and fluid, making it difficult to breathe and absorb oxygen.

The most common pneumonia is caused by the bacterium Streptococcus pneumoniae or pneumococcus, and causes a high fever, pain in breathing, coughing, and bloody sputum. It is treated with the antibiotic penicillin. If it also affects the bronchi, it is called bronchopneumonia.

Lung cancer

The lung cancer is uncontrolled cell growth that develop in the bronchi and invade and destroy lung tissue.

It causes the lung to malfunction, causing pain and even death.

Although anyone can get lung cancer, it is more common in smokers, since tobacco smoke contains many cancer-promoting substances, such as tar.

Common cold

The cold is caused by a viral infection that causes inflammation of the nasal membranes, generating a thick mucous discharge, runny and stuffy nose, sore throat and cough. Fever is not usually present.

Being caused by viruses, antibiotics are not suitable (viruses are not living beings and only work against bacterial infections), and treatments only serve to relieve symptoms, not to cure them. It usually subsides in a week.


The flu or influenza is caused by viruses. It is more serious than the cold, since in addition to fatigue, sneezing, mucus and sore throat, it is often accompanied by muscle aches, chills and fever.

There is no curative treatment, but pain relievers can relieve symptoms. It disappears after several days. 

Pulmonary edema

The pulmonary edema is the accumulation of fluid inside the lungs. It occurs when there is a problem in the circulation of the blood and the heart cannot pump blood efficiently, being dammed in the blood vessels that carry blood to the lungs. When the pressure in these vessels increases, the liquid passes into the lung alveoli, flooding them and reducing their ability to exchange gases, leaving the body without oxygen.

Pulmonary embolism

The pulmonary embolism occurs when a pulmonary artery is blocked. Normally, it originates when a blood vessel is blocked (thrombosis) in the veins of the pelvis or legs, and part of that clot breaks off (embolus) travels towards the heart and from there, to the pulmonary artery that is blocked.

Pulmonary emphysema

The emphysema is increased the size of the lung alveoli, impairing gas exchange. Although more air enters the alveoli, the blood cannot take in oxygen or leave CO2, so the body has trouble getting the oxygen it needs.

The main cause of this deterioration of the lungs is tobacco. This disease is chronic, with a slow and progressive process.


The hypo is the involuntary contraction of the diaphragm and intercostal muscles, together with the larynx and closure of the epiglottis to prevent the inspiration air. It usually starts spontaneously and lasts for a few minutes.

The diaphragm is a muscle that is under the lungs and is responsible for pulmonary ventilation. It usually works properly, but sometimes it gets irritated. Then, the air quickly enters the larynx and the epiglottis closes and the “hip” sounds characteristic of hiccups. Eating too quickly, being nervous, abusing alcohol, upset stomach, etc., are some of the causes that can cause this irritation.


The tuberculosis is an infection bacterial (Mycobacterium tuberculosis) contagious that affects the lungs, causing coughing, chest pain and bloody sputum, but can also affect the digestive system, skin, nervous system, etc.

The bacillus is spread through the air, when a person with tuberculosis coughs, sneezes, speaks, or spits. If a person inhales bacteria that may be in airborne droplets or dust particles, they can become infected.

To treat tuberculosis it is necessary to use antibiotics.


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