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Thermoactinomyces candidus Antibodies

Test ID:

705335

CPT code:

86602

Synonyms:

Thermoactinomyces candidus Precipitating Antibodies, IgG
Forced Air System Disease
Hypersensitivity Pneumonitis

Clinical Use:

Confirm the presence of precipitating antibodies to Thermoactinomyces candidu

Test Information:

Hypersensitivity pneumonitis (HP), also referred to as extrinsic allergic alveolitis (EAA), is an inflammatory lung disease resulting from the inhalation and subsequent sensitization to a wide variety of inhaled organic dusts. HP is not mediated by IgE. It is associated with progressive pulmonary disability, irreversible lung damage, and mortality in some occupational settings. Patients often present with intermittent chills, fever, cough, and shortness of breath that begin 4 to 8 hours after exposure to the offending dust.
Thermophilic actinomycetes can be found in soil, foods, fresh water, and other natural sources. These organisms grow well in decaying organic materials at temperatures often attained during decomposition. Exposure to Thermoactinomyces candidus can result from contact with a contaminated heating system causing a condition referred to as forced air system disease
No single laboratory test is diagnostic for hypersensitivity pneumonitis. Diagnosis is based on a complete environmental history supported by result of chest x-ray, spirometry, and in vitro immunologic tests. Identification of the causative agent is important to allow avoidance of exposure. Double diffusion (Ouchterlony) assays are typically used to determine antigen-specific IgG antibodies. The appearance of precipitin arcs confirms the presence of precipitating antibodies to specific antigens. These antibodies may also be present in individuals not afflicted with HP. The presence of antibodies to the offending dust or antigen confirms exposure but is not diagnostic of HP; however, upon repeated or prolonged exposures, high levels of precipitating IgG antibodies are typically observed.