Proposed criteria for mixed-dust pneumoconiosis: definition, descriptions, and guidelines for pathologic diagnosis and clinical correlation.
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers' pneumoconiosis, silicosis, hematite miners' pneumoconiosis, welders' pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders.
Honma
Koichi
K
Department of Pathology, Dokkyo University School of Medicine, Mibu, Tochigi, Japan.
Abraham
Jerrold L
JL
Chiyotani
Keizo
K
De Vuyst
Paul
P
Dumortier
Pascal
P
Gibbs
Allen R
AR
Green
Francis H Y
FH
Hosoda
Yutaka
Y
Iwai
Kazuro
K
Williams
William Jones
WJ
Kohyama
Norihiko
N
Ostiguy
Gaston
G
Roggli
Victor L
VL
Shida
Hisao
H
Taguchi
Osamu
O
Vallyathan
Val
V
D004391:Dust; D006801:Humans; D007391:International Cooperation; D008168:Lung / Q000473:pathology*; D008903:Minerals; D016273:Occupational Exposure / Q000009:adverse effects; D011009:Pneumoconiosis / Q000145:classification / Q000209:etiology / Q000473:pathology*; D017410:Practice Guidelines as Topic; D012822:Silicon Dioxide / Q000009:adverse effects
D004391:Dust; D008903:Minerals; D012822:Silicon Dioxide