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auscultatory skill. The physician who does not concen
A joint committee of the ACCP/ATS, chaired by Dn
trate because he is distracted or hurryingwill miss faint Raymond H. L. Murphy, was charged with the respon
sounds.
sibility of providing a consensus view on diagnostic
Our cardiologic teachers are challenged to improve issues in the group ofnonmalignant diseases for which
auscultatory education in the face of the exciting new compensation is being sought by thousands of former
diagnostic technology that may overshadow more workers who allege injury due to their asbestos expo
mundane bedside findings. Surely a sign as simple and sure. The resulting statement has recently been pub
informative as the S, ofheart failure is worth preserving lished.* Because there is often alarming abuse ofsound
and emphasizing. It is particularly appropriate that medical principles and distortion of scientific knowl
internists, pediatricians and family physicians--the edge, frequently perceived orjustified as being benefi
"gatekeepers"--retain the ability to detect such basic cial to claimants, several points covered in this report
findings as bedside evidence ofheart failure.
will be highlighted. The comments are mine and do
Let us hope that the next group assessment of not necessarily reflect the views of the committee.
auscultatory skill will find that most observers can hear
Asbestosis is a term which indicates diffuse lung
Sj. fibrosis due to asbestos exposure. Its use is not correct
John F. Stapleton, M.D. in reference to pleural abnormalities. The diagnosis of
. . _ ___ -------u.-... Washington, DC asbestosis is most often established by one or more
Medical Director Georgetown University Hospital.
clinical or laboratory findings, in conjunction with a history of nontrivial exposure. In fact, this diagnosis
will almost always depend primarily on a radiographic
appearance compatible with diffuse interstitial infiltra
tions, in addition to any other abnormalities which may
Diagnosis of Asbestos-related Disease
be present on the chest radiograph. While it is rarely necessary, or possible, to examine lung tissue in order to make a diagnosis of asbestosis, when a pathologic
diagnosis is made it must be based on the demonstra
tion ofboth asbestos bodies and fibrosis. Neitheralone
is sufficient As in the pathologic diagnosis of other
sound scientific and medical knowledge. The catego diffuse lung diseases, attention must be paid to ade
ries of these policy issues are: 1) estimation of risks,
quate size and representativeness ofthe tissue sample.
which may not be measurable at current levels of
As indicated, the chest x-ray film plays a central role
exposure but which could lead to disease if exposures iu the diagnosis of asbestosis. Improved radiographic
are not sufficiently controlled, and 2) adequate and technique and quality assurance make possible the
equitable compensation of workers who have been sensitive detection, by experienced readers, of as
injuredby past exposures to asbestos in the workplace. bestosis of even minimal extent The international
The first requires a data base derived from epi classification for the pneumoconioses1 includes grad
demiologic studies of populations exposed to asbestos ing ofthe irregular and linear opacities characteristic of
for whom valid quantitative health and exposure infor asbestosis. The classification was designed to be used
mation is available-BesulUag exposure-response rela
for epidemiologic research and has been helpful in
tionships can lead to the setting ofprotective occupa encouraging the training ofqualified readers. Indeed,
tional standards and the appropriate allocation of many physicians have taken tests, using standard films,
resources to maximize health benefit when competing ui order to become "certified readers," often for the
risks are presented to policy-makers for amelioration.
purpose of establishing credibility when making a
The second issue can only be sensibly addressed radiographic diagnosis of asbestosis (or other pneu
when, as in other areas ofmedicine, diagnosis is based moconiosis) in the litigation/compensation arena.
on generally accepted criteria which are supported by There have been undesirable consequences ofthe use
the known pathophysiology of the disease. With the of the ILO Classification for this purpose.
asbestos-induced illnesses, there is no absolute speci
The classification is intended to be descriptive,
ficity, as it relates to causation, only degrees of non- albeit quantitative. The 12 categories of profusion of
specifidty. Mesothelial tumors in asbestos-exposed small opacities cover the range from normal to marked.
individuals are very likely to be caused by this expo It is at the lower categories (0/1 to L/l) that the greatest
sure, in contrast to lung cancer which, even in exposed
degree of interobserver variability (disagreement) oc
persons, is more likely the result ofsmoking. A similar curs. No one category will constitute the lower limit of
range in the degree ofcausal specificity is found in the abnormalities which is "diagnostic" ofasbestosis for all
onmalignant conditions known to result bom asbestos qualified readers. For one reader this levelwill more or
exposure.
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less be equivalent to an ILO reading of 1/1 for irregular
802 - - -
Editorial*
I'
small opacities, for another 110. In the p^.t, categories
Improving the standard . diagnosis in the asbestos-
high uS 2/2 have been suggested.
'
related diseases is important not only because limited .
It is unfortunate that some readers have interpreted public and private resources should go to those with
the ACCP/ATS statement to suggest that a reading ofat true occupationally-induced injury. As physicians, we
least 1/1 for small opacities is required to support a have a responsibility to be truthful and humane in our ~
diagnosis of asbestosis. It is more appropriate to dealings with patients, including those being evalu
consider that level as illustrative of a film compatible ated for an occupational disease. Both over;- and under- --
with asbestosis. So might also a category 1/0 film; it diagnosis can be detrimental. Overdiagnosis wifi evoke
depends on the reader Should there be any who think needless fear and perceived incapacity in normal
that "mandating" a category sufficient to make a individuals---too great a price for possible (usually
diagnosis of asbestosis will lead to standardization, it minimal) economic gain. Underdiagnosis can delay
should t>e remembered that any such category can be appropriate compensation, increasing die burden of
inappropriately chosen by a given reader, just as now disease on an ill worker and his family. Either pre
interstitial fibrosis is often "read" on a negative film. mature or delayed diagnosis can, depending on state
Choosing a "diagnostic" category will not, regrettably, law, result in loss of any chance for compensation. ' .
suffice to confer credibility on the system.
Diagnostic standards are needed and achievable,
A physiologic pattern of reduced lung volumes and even in occupational disease. Credentialing in the
disturbed-gw transfer "ar~the*fhidiiig ofinspiratory- - --specialties" of medieme^depends on-evaluaiiag can-_
crackles are supportive of the diagnosis but are too didates on their cognitive knowledge regarding,
nonspecific to be helpful in isolation. Clubbing (also among other things, diagnostic criteria. Some in the
nonspecific)is too rare to be useful; dyspnea is almost legal community are determined to resist medical . _
always present in claimants and can therefore not be a standards for diagnosing these diseases, citing .the
discriminating feature.
undermining of the tort system (ever)' claimant should .
The Sbrotic process of asbestosis begins in peri have his day in court). They frequently have allies
bronchiolar areas of the lung. Peripheral airways among their medical consultants and witnesses._The `
dysfunction has been demonstrated in population large number ofclaims and lawsuits for asbestosis, and '
studjes and the pathologic analog described. However; other asbestos-related diseases, makes the need for
clinical and epidemiologic evidence is now more than credible diagnosis even more urgent .........
r-.
sufficient to firmly conclude that clinically significant
_
Hans Weill, M.D., EC.C.E
chronic airways obstruction is not an expected conse quence ofasbestos exposure in the absence offar more
A'ets Orleans .
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important causal factors, most notably, smoking. Pleural thickening, focal (plaques) or diffuse, results
from asbestos exposure. Plaques do not affect lung
Schlieder Foundation Professor of Pulmonary Medicine, Tulane
Medical Centec
`
lUprint requests: Dr. WeiU, Tulane Medical Center 1700 Serdida' -
Street, New Orleans 70112
__
function, and diffuse pleural thickening reduces lung
volumes only when it is very extensive. It is still not
References
"..
clear if the presence of benign pleural abnormalities
1 Statement of the American Thoracic Society. The
of '
constitutes a risk factor (beyond exposure) for the development of asbestos-related tumors. Whether pleural effects are compensable is, ofcourse, a societal^ decision. It should, however, be based on accurate information.
nonmalignant dileases related to asbestos. Am Rev Kespir Dis 1986; 134:363-68 2 International Labour Office. Cuidcliac* Cx the use of HjO -- international cluiiGoation ofradiograph* cfpneumocoaioii**, rrv ed 1980. Occupational Safety and Health series No 22. Geneva: International Labour Office, 1980
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CHEST / 91 / 8 / JUNE. 1987 803