The industrial hygeinst or environmental scientist will make the decision to conduct additional sampling. Types
Hypersensitivity pneumonitis may also be called many different names, based on the provoking antigen. These include:

Of these types, Farmers Lung and Bird-Breeders Lung are the most common. "Studies document 8-540 cases per 100,000 persons per year for farmers and 6000-21,000 cases per 100,000 persons per year for pigeon breeders. High attack rates are documented in sporadic outbreaks. Prevalence varies by region, climate, and farming practices. HP affects 0.4–7% of the farming population. Reported prevalence among bird fanciers is estimated to be 20-20,000 cases per 100,000 persons at risk." Imaging
No single imaging finding is singularly definitive of a diagnosis rather clinicians rely on a constellation of findings. Both chest radiographs and high resolution CT scans can be normal. Chest Radiographs
Acute presentation may reveal poorly defined a micro-nodular interstitial pattern and ground-glass opacities in the lower and mid lung zones. In addition to this, subacute presentations may show reticular nodular opacities in mid-to-lower lung zones. Chronic forms may show fibrotic changes and appear like Idiopathic pulmonary fibrosis. High-Resolution Computed Tomography
This has become a common diagnostic imaging for the diagnosis and is the modality used in the Official ATS/JRS/ALAT Clinical Practice Guideline. Two forms of hypersensitivity pneumonitis are fibrotic and non-fibrotic findings on chest CT. The two differ in terms of their diagnostic work up and management although there is overall between them. The non-fibrotic form is typically characterized by ground glass opacities, mosaic attenuation, ill-defined centrilobular nodules (<5 mm), and air trapping.
Osteopathia striata is a rare entity characterized by fine linear striations about 2- to 3-mm-thick, visible by radiographic examination, in the metaphyses and diaphyses of long or flat bones. It is often asymptomatic, and is often discovered incidentally. See also
List of radiographic findings associated with cutaneous conditions


== References ==