The term hypersensitivity pneumonitis, often referred to as extrinsic allergic alveolitis, describes a collection of lung conditions in which your lungs swell up due to an allergic reaction brought on by exposure to dusts with both animal and plant origins. Although confusing, the term ""extrinsic allergic alveolitis"" accurately captures the cause and characteristics of these illnesses. Extrinsic causes are those that originate from outside the body, allergic causes are those that result from an immune system reaction to a certain chemical or condition, and alveolitis is an inflammation of the lining of the lungs (alveoli are the small air sacs in the lungs)
Why does hypersensitive pneumonitis occur?
Hypersensitivity pneumonitis can be brought on by intense or extended exposure to animal or vegetable dusts. To enter the alveoli, the dust particles must be 5 microns in size or smaller. Animal and vegetable dusts are intricate combinations made of many various materials, including husks, bark, wood, animal dander, and bacteria and fungi. The combination contains the harmful compounds that the microbes create. The dusts may also contain insects and insect fragments, bird droppings, and dried rat urine. Other causes of dust include grain, straw, moldy hay, and feathers.
How does the onset of hypersensitivity pneumonitis occur?
The first day of exposure to animal and plant dusts does not result in the development of hypersensitivity pneumonitis. Exposure that is extended and repeated is necessary. Only a small percentage of employees still experience allergic reactions to the dusts. 10% to 40% of those who are exposed do not exhibit any symptoms. The body's complex natural defensive mechanisms, which typically shield the lungs from external chemicals, are what cause the allergy. In certain people, the defense system's chemical processes that normally protect the lungs are what actually lead to inflammation and lung damage. Sensitization describes the body's evolving reaction to breathing in dust.
What signs and symptoms are present in hypersensitive pneumonitis?
Once a person is sensitized, hypersensitivity pneumonitis can manifest in three different ways: acute (intense), sub-acute (recurrent), and chronic (long-term). Individuals will experience different signs and symptoms. Heavy exposure to the trigger causes the acute attack to start. It begins with a fever, aches in the muscles, and a generalized malaise. Shortness of breath, a dry cough, and chest tightness go along with these symptoms. Between 4 and 8 hours after exposure, symptoms could appear. People who have been exposed to relatively low levels of dust are more likely to experience the sub-acute reaction. Cough, persistent bronchitis, shortness of breath, anorexia, or weight loss are symptoms. After repeated acute attacks and subacute reactions, the chronic response forms. It is characterized by lung fibrosis, chronic bronchitis, shortness of breath, anorexia, or weight loss. Damage to the victim's lungs is permanent.
How is hypersensitivity lung disease diagnosed and handled?
The patient's employment and a history of contact with plant or animal dusts are the best indicators of hypersensitivity pneumonitis in terms of diagnosis. Despite the fact that the doctor may want to perform some tests, such as lung x-rays, blood tests, or lung function tests, these are not precise and may not be able to differentiate between hypersensitivity pneumonitis/extrinsic allergic alveolitis and/or other lung disorders. After receiving a diagnosis, the patient must stay away from dusts from plants and animals in the future. Improvement is the sole outcome of this action. Patients who have significant conditions require breathing aids.
What professions are at risk?
Pneumonitis caused by hypersensitivity can occur in a wide range of professions. This is not a comprehensive list. The examples and associated professions are shown in the table below. Illustrations of Hypersensitivity Disease of Pneumonitis Exposure Maintenance in advance Humidifier and air conditioner lung hygrometer water upkeep of systems for handling air and water. lungs of animal handlers Dander-producing dust, hair fragments, and dried rat urine good ventilation for exhaust. Bagassosis Infected sugar cane bagasse is treated with propionic acid. good ventilation for exhaust. maintaining a moisture content of over 20%. processing enclosed. bird enthusiasts' lung Feathers and crumbs good ventilation for exhaust. while cleaning, water is sprayed on waste. Loudspeaker's lung Cheese fungus aging the cheese in a foil pouch. Landowners' lung Hay, straw, and grain with mold See ""Dust Control"" in the section after this. Sauna lung Bacteria in hot tub mist Keep the water's disinfectant level constant. routine hot tub maintenance. good ventilation for exhaust. lung of a maltster stale malt mechanical techniques used in the malting process. Bark strippers' disease in maples Maple bark with mold. Debarking involves spraying logs. some operations are controlled remotely. lung of a mushroom worker Compost with moldy mushrooms good ventilation for exhaust. Sequoiosis Mouldy sawdust good ventilation for exhaust. processing enclosed. Sewage sludge disease Dust of heat-treated sludge good ventilation for exhaust. At outside facilities, stand upwind of storage piles. Wheat weevil lung / Miller’s lung Mouldy grain, flour, dust See """"Dust Control"""" in next section. Suberosis Mouldy cork dust Good exhaust ventilation. Wood pulp workers' disease Mouldy wood chips Good exhaust ventilation. Remote control of some operations.
How can we prevent hypersensitivity pneumonitis?
The means for reducing dust exposure (dust control) include engineering control and personal protective equipment. Education is also important, and educational programs should emphasize the significance of animal and vegetable dust in causing diseases. Managers and workers should learn about methods of storing materials to prevent mould formation and to reduce dust. Methods of engineering control include local exhaust ventilation, general ventilation, process enclosure and process isolation (separating the worker from the dusty process). On farms, prevention of particle release and control of dust cloud formation are achieved by well-designed, leakproof ducting, and enclosed conveyor systems for grains and feeds. Buildings should have local ventilation systems in areas frequented by workers engaged in egg-handling and feed storage and preparation. Within enclosed livestock units, temperature and relative humidity should be monitored. Adequate ventilation and sufficient fresh, replacement air should be provided. For field operations, tractors or combine harvesters with enclosed cabs provided with filtered air should be used. Personal protective equipment may be vital but it should be considered as the last resort for respiratory protection. Personal protective equipment should not be a substitute for proper dust control. Respirators, including dust masks, should only be used: when engineering or administrative controls are not technically feasible, when engineering controls are being installed or repaired, or when emergencies or other temporary situations arise (e.g., maintenance operations). If respiratory protective equipment is needed for the job, then a full respiratory program should be put in place that includes selection, use, and care of respirators plus training and education for the worker. Because respirators provide different levels of protection, it is very important to assess the airborne contaminant before selecting the specific type of respirator."""