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  Home > Articles > Diagnosis, Management of Asbestos Related Disease  

New ATS Criteria
for Non-Malignant Asbestos Related Diseases


By Dr. Noel Kerin

The American Thoracic Society (ATS) recently updated their Statement on the
Diagnosis and Initial Management of Non-Malignant Asbestos Related Disease.
The ATS had not updated their Statement in this area since March of 1986. There are many differences between the 1986 and 2004 ATS statements, including more weight given in the 2004 statement to subjective symptoms such as dyspnea, non-productive cough, wheezing, and intermittent chest pain is given. The 2004 Statement of the ATS is much broader in applying different categories of asbestos-related disease and much more permissive in its criteria for diagnosing asbestos-related impairment.

The new criteria can be summarized as follows

Evidence of structural change, as demonstrated by one or more of the following:
  • Chest x-ray, CT or HRCT scan
  • Pathology samples

    • Evidence of plausible causation, as demonstrated by one or more of the following:
  • Occupational and environmental history of exposure (with plausible latency)
  • Markers of exposure, such as pleural plaques
  • Recovery of asbestos bodies on pathology review


    • Exclusion of alternative diagnoses

    Evidence of functional impairment, as demonstrated by one or more of the following:
  • Signs and symptoms of impairment
  • Reduced ventilatory capacity evidencing restrictive and or obstructive disease
  • Impaired gas exchange
  • reduced diffusion capacity
  • Inflammation on bronchiolar lavage
  • Exercise testing impairment

The most significant differences and what they mean

The new criteria make a point of stating that significant exposures of less than a year can cause asbestosis and that bystander exposures in the right setting may also be sufficient.

The requisite ILO profusion score for asbestosis has been lowered to 1/0. This requirement is further diluted by categorizing the 0/1 profusion score as "suggestive," and adding that 15 - 20% of individuals with no radiographic evidence of asbestosis had histo-pathologic findings of parenchymal asbestosis.

The authors also promote high resolution CT scanning as being able to find asbestosis in 34% of asbestos-exposed workers with 0/0 or 0/1 profusion scores on plain chest x-ray.

While the 2004 criteria concede that restrictive impairment is the classic finding of asbestosis on pulmonary function testing, the ATS statement adds that mixed restrictive and obstructive impairment is frequently seen, and that asbestos exposure has been associated with obstructive physiological abnormalities which may or may not be attributable to asbestos exposure.

The new criteria revisit the finding of pleural plaques as an inconsequential marker and suggest that some studies have attributed a reduction in lung function to plaques, and that plaques have been associated with both restrictive impairment and diminished diffusing capacity.

The new statement also espouses medical monitoring every 3 to 5 years for anyone with a history of exposure but no manifest disease.

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