Case 9: Talcosis in a Vermont Talc Miner: Not Idiopathic Pulmonary Fibrosis

This is an example of a biopsy proven case of talcosis in a 61 year-old man who had worked 30 years in the Vermont Talc mining operations. He began work in 1965 for Eastern Magnesia, which was purchased by Johnson & Johnson in 1965, and sold to Cyprus Minerals in 1989. In 1992 it was sold to Luzenac. The talc processed came from Windsor and Ludlow, Vermont. The initial diagnosis was of 'silicosis' in mid 2000. A Worker's Compensation claim was denied by Luzenac in October 2000, but reversed and awarded on appeal in 2005.

LM of parenchymal area
Light Microscopy (LM) of parenchymal area. Polarized LM of parenchymal area
Polarized LM of parenchymal area. X-ray microanalysis of talc particles
Scanning electron microscopy and EDS spectrum of talc particles in lung tissue.

His CT scan report mentioned the history of grinding talc x 30 years. May 2000: "There are bullous changes in both lungs with prominent interstitial markings and honeycombing, predominantly in the upper lobes, right greater than left, and less so at the bases. Focal areas of dense calcifications in the lift hilum." June 2004: "The lung parenchyma demonstrates diffuse interstitial disease with fibrosis and honeycombing which is more extensive than on the prior examination. There is also extensive new patchy ground glass opacity, a finding which likely largely represents progression of interstitial disease, but may also reflect a degree of alveolar consolidation, such as with pneumonitis or pneumonia."

A transbronchial biopsy was done in June 2000. The findings are shown in the accompanying figures. The images show light microscopy demonstrating typical talc macules and innumerable strongly birefringent platy particles typical for talc, with some fibrosis. Microanalysis of the tissues using SEM/EDS confirmed that the vast majority of the inorganic particles were indeed Mg+Si consistent in ratio with talc. Very little silica was detected in the SEM/EDS analysis, and no silicotic nodules had been seen by light microscopy of the biopsy.

A pulmonary consultant for the Mining Company, which contested the Worker's Compensation Claim, stated that despite the history of many years in talc mining and the demonstration of talc and fibrosis in the biopsy, the correct diagnosis was 'Idiopathic Pulmonary Fibrosis (IPF).'

The American Thoracic Society (ATS) criteria for diagnosis of IPF include the statement that known causes of pulmonary fibrosis, including environmental exposures, must be excluded before rendering that diagnosis. The first Major Criterion is "Exclusion of other known causes of interstitial lung disease (ILD), such as certain drug toxicities, environmental exposures, and connective tissue diseases."

Pure talcosis without asbestosis or silicosis has been reported. A case of talcosis diagnosed by transbronchial biopsy was reported in 1982. Subsequent to the publication, this patient died from talcosis (personal communication from Dr. Z. Mohsenifar). There are four patterns of talcosis, according to a review in Rom's textbook of occupational medicine: talcosilicosis (with talc associated with significant silica exposure), talcoasbestosis (with talc associated with significant asbestos exposure), talcosis (caused by talc without significant silica or asbestos contamination) and intravenous talc granulomatous disease (in drug abusers). For a discussion of fibrous and asbestiform talc, a few references and links are provided below.

References

LM of parenchymal area
Polarized LM of parenchymal area
X-ray microanalysis of talc particles