Hypersensitivity pneumonitis overview

Hypersensitivity pneumonitis Microchapters
Home
Patient Information
Overview
Historical Perspective
Classification
Pathophysiology
Causes
Differentiating Hypersensitivity pneumonitis from other Diseases
Epidemiology and Demographics
Risk Factors
Screening
Natural History, Complications & Prognosis
Diagnosis
Diagnostic Criteria
History and Symptoms
Physical Examination
Laboratory Findings
Electrocardiogram
Chest X Ray
CT
MRI
Other Imaging Findings
Other Diagnostic Studies
Treatment
Medical Therapy
Surgery
Primary Prevention
Secondary Prevention
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Hypersensitivity pneumonitis overview On the Web
Most recent articles
Most cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Hypersensitivity pneumonitis overview All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Hypersensitivity pneumonitis overview
CDC on Hypersensitivity pneumonitis overview
Hypersensitivity pneumonitis overview in the news
Blogs on Hypersensitivity pneumonitis overview
Directions to Hospitals Treating Hypersensitivity pneumonitis
Risk calculators and risk factors for Hypersensitivity pneumonitis overview

For the WikiPatient page for this topic, click here

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Hypersensitivity pneumonitis (HP), also called extrinsic allergic alveolitis (EAA), is not a single disease but is a complex syndrome of varying intensity, clinical presentation, and natural history.

The syndrome was first described in Iceland in 1874 and termed heykatarr. The syndrome is caused by sensitization to repeated inhalation of dusts containing one of 300 organic antigens. These organic dusts come from a wide variety of sources but most commonly include:

• Dairy and grain products
• Animal dander and protein
• Wood bark
• Water reservoir vaporizers

The two most common antigens are:

1. Thermophilic actinomycetes and
2. Avian proteins

As a rseult of exposure to thee antigens, the two most common causes (i.e. diseases) are:

1. Farmer's lung and
2. Bird fancier's lung

Pathologically, the HP syndrome is associated with diffuse inflammation of lung parenchyma and airways.

Based on the length and intensity of exposure and subsequent duration of illness, there are 3 clinical presentations of HP:

1. Acute
2. Subacute (intermittent)
3. Chronic progressive

Synonyms and related keywords: hypersensitivity pneumonitis, HP, bird fancier's lung, extrinsic allergic alveolitis, farmer's lung, Saccharopolyspora rectivirgula, S rectivirgula, Micropolyspora faeni, M faeni, Thermoactinomyces sacchari, T sacchari, Thermoactinomyces vulgaris, T vulgaris, Penicillium casei, P casei, Aspergillus clavatus, A clavatus, Mucor stolonifer, M stolonifer, Sitophilus granarius, S granarius, Cladosporium, heykatarr, bagassosis, grain handler's lung, humidifier lung, air-conditioner lung, bird breeder's lung, cheese worker's lung, malt worker's lung,paprika splitter's lung, mollusk shell hypersensitivity, chemical worker's lung, pulmonary disease, lung disease.

References

Template:Respiratory pathology