Alveolitis is an inflammation of the small alveoli, where the gas exchange between blood and air takes place. Alveolitis develops in many cases due to work. Farmers who inhale the dust of moldy hay are often affected. Read all about the symptoms, diagnosis and treatment of alveolitis.
Alveolitis: description
Alveoli are small blisters inside the lungs. A full-blown lung contains around 400 million such alveoli. They form an area of about 100 square meters for the exchange of oxygen and carbon dioxide.
In the alveoli, the oxygen of the inhaled air is absorbed into the blood and carbon dioxide is released from the blood into the air. If the alveoli become inflamed, this is called alveolitis. It is an allergic reaction to proteins or fungal spores (allergens) in organic dusts (exogenous allergic alveolitis, EAA), The dusts contain fungal spores or animal proteins to which the immune system mistakenly reacts.
Alveolitis can be sudden with severe symptoms or gradually develop over a long period of time with various symptoms. EAA is a relatively rare disease. The most common are the so-called birdhouse lung, the farmer lung and the humidifier lung.
Bird fancier’s lung
This form of EAA is an allergy to bird droppings and avian egg whites of budgerigars, canaries, pigeons and chickens. Contact with egg proteins from rodents can also trigger an EAA.
farmer’s lung
Farmer lung is the second most common form of exogenous allergic alveolitis. It is caused by an allergic reaction to fungal spores in moldy hay.
Befeuchterlunge
If indoor units are equipped with humidifiers or air conditioning, even the smallest water droplets may be contaminated with fungal spores. These trigger an EAA on repeated contact. The EAA can also be triggered by mold in the interior or in the mattress, in the machine oil in the compost soil, in the water bucket of the sauna or in the whirlpool.
Chemical substances
In spray paint, two-component adhesive and polyurethane foam production, chemical substances are released which can trigger alveolitis.
Alveolitis: symptoms
EAA often occurs six to 16 hours after contact with the allergen. Those affected feel ill, have body aches, cough and shortness of breath. Sometimes fever occurs. The nose and throat are inflamed like a cold. The symptoms can easily be confused with those of pneumonia. If contact with the allergen is interrupted, the symptoms will decrease within two to four days. Sometimes, however, the symptoms may last for weeks.
Continued contact with the allergen will make the symptoms more diffuse. Those affected report weight loss, persistent fatigue, shortness of breath during exercise and headache. Often, asthma occurs and the lung tissue scar (lung fibrosis).
pulmonary fibrosis
Pulmonary fibrosis can also have many other causes. Everything important to read in the article Pulmonary fibrosis!
Alveolitis: causes and risk factors
Alveolitis is due to an allergic reaction to proteins or mold spores. First, the immune system is sensitized to a particular allergen like mold spores. It produces antibodies against it. If the spores are inhaled again, the immune system reacts and triggers an inflammatory reaction in the alveoli. There are more than 300 allergens known to cause exogenous allergic alveolitis.
Although the disease is rare, it occurs more often in risk groups such as bird breeders or farmers and can lead to occupational disability. For reasons that are still unclear, smokers seldom contract an EAA.
Alveolitis: examinations and diagnosis
If symptoms of the disease occur, you can first turn to a work doctor or a pulmonologist. A quick diagnosis is important to be able to treat quickly and to prevent long-term damage to the lungs. In a first interview, the doctor will first ask the following questions:
- What profession do you practice and how long?
- What is your hobby?
- Are you already suffering from lung or skin diseases or allergies?
This is followed by a physical examination.
Lung x-ray
If there is a suspicion of a lung disease, an X-ray or a so-called computer tomographic image must be made. Here you can already get important information on a lung disease.
Bronchoalveolar lavage
The so-called bronchoalveolar lavage is a study in which the alveolitis can be diagnosed very reliably. For this purpose, a so-called bronchoscope, a rigid or a flexible tube with an integrated camera, introduced through the nose or mouth into the respiratory tract. The doctor uses the bronchoscope to direct rinsing fluid into the lungs. Afterwards it is sucked off again. The recovered liquid can be further tested in the laboratory. In an EAA, many so-called cells of the immune system can be detected in the absorbed fluid.
Pulmonary function test
A pulmonary function test is used to check if and how severe the lung function is affected by the alveolitis. In doing so, the patient must vigorously inhale and exhale through a mouthpiece. It is measured how much air the patient can inhale and exhale in which time.
blood test
Certain values may be elevated in the blood, indicating an allergic reaction or inflammation.
biopsy
At an advanced stage of disease, sometimes a small sample of lung tissue must be removed and examined under the microscope to confirm the diagnosis.
Provocation and parole test
In addition to the investigations mentioned, provocation or parental tests can also confirm the diagnosis of an EAA. In these tests, either more allergens are added and the course of the symptoms is observed or the patient is kept away from all potential allergens. If symptoms improve, chances are it’s an EAA.
Alveolitis: treatment
First, the patient should have no further contact with the allergen. Dust masks and protective suits can prevent those affected from being exposed to the allergens. Also structural changes, hay drying or the maintenance of air conditioners must be taken as protective measures. In some cases, however, a job change is necessary.
Inhalation of cortisone
Alveolitis must be treated as quickly as possible. In many cases cortisone is used to stop the inflammatory process as quickly as possible. In case of difficulty breathing, a cortisone inhalation spray can help you better again. In some cases, other medicines that inhibit the immune system, such as azathioprine or cyclosphosphamide, must be used to stop the inflammatory process.
Alveolitis: disease course and prognosis
If the affected persons manage to avoid the triggering allergens, the EAA often heals by itself. However, if the disease is discovered and treated too late, the lung structure may be permanently damaged. The lung skeleton thickens, the lung becomes less elastic (pulmonary fibrosis). The heart must pump against a higher resistance in a thickened lung scaffold. In the long term, this can also damage the heart.
prevention
To prevent alveolitis, one should not give mushroom spores a chance to multiply. In humidifiers, air conditioners or indoor wells mushrooms can grow very well. Mattresses should be ventilated again and again. In workplaces where organic dusts are often inhaled, regular occupational medical examinations have to take place in order to prevent one alveolitis submissions.