Investigation of rare chronic lipoid pneumonia associated with occupational exposure to paraffin aerosol

Abstract

Objectives: Occupational exposure to paraffin is an infrequent cause of lipoid pneumonia (LP) and related data are scare. We investigated the possible relationship between three rare cases of chronic LP and occupational exposure to paraffin aerosol in an iron foundry. Methods: The three cases of LP and their workplaces were investigated using data from field investigations, air monitoring, pulmonary radiological examinations, cell staining, and lung biopsies. Results: The patients had long-term occupational exposure to paraffin. X-ray diffraction testing revealed that the raw material from the workshop was paraffin crystal. The air concentrations of paraffin aerosol in workplaces were significantly higher than outdoor background levels. Small diffuse and miliary shadows with unclear edges were observed throughout the whole lungs via radiography. Computed tomography revealed diffuse punctate nodules and a high density of stripe-like shadows in both lungs (ground-glass opacity in a lower lobe, and a mass-like lesion and high translucent area near the bottom of the lung). Lipid-laden macrophages were found in the sputum and bronchial lavage. A broadened alveolar septum and local focal fibrosis were also discovered via lung biopsy. The inflammatory reaction in the lung tissues appeared to resolve over time. Conclusions: These three rare cases of chronic LP in workers during molding and repair processes were associated with occupational paraffin aerosol exposure. Therefore, primary prevention is essential for molding or repairing workers in the iron foundry, and a differential diagnosis of occupational chronic LP (vs. pneumoconiosis) should be considered when treating these workers.

The Occupational Burden of Nonmalignant Respiratory Diseases. An Official American Thoracic Society and European Respiratory Society Statement

“…Reanalyses after excluding (113) Lung tissue particles 37 35 Rubin, 1980, Canada (114) Reported history 13 15 Kariman, 1984, USA (115) Reported history 23 0 Prakash, 1987, USA (116) Reported history 34 9 Asamoto, 1995, Japan (117) Reported history 68 15 Goldstein, 1998, USA (118) Reported history 24 50 Kim, 1999, Korea (119) Reported 137Reported history 17 29 Mo, 2016, China (138) Reported history 11 18 Guo, 2017, China (139) Reported history 37 49 Hwang, 2017, Korea 140Reported history 71 48 Definition of abbreviation: USA = United States. All studies are case series except four case-control studies (113,126,133,158) and one national registry (121). "Reported history" refers to occupational or exposure history from the clinical record.…”

“…Although PAP has a more robust literature relevant to the occupational burden of disease, there are a number of other respiratory syndromes in which occupational associations have been observed in disease outbreaks, in certain work settings, or after suspect exposures (142,(145)(146)(147)(148)(149)(150)(151)(152)(153)(154)(155)(156)(157)(158)(159)(160)(161). Table E2 provides selected examples of these reported associations, which include bronchiolitis and the Overall (I^2 = 99.72%, p = 0.00) All studies had case-control designs, with most by interview-based self-reported exposure assessment (Hubbard exposure by job category).…”

“…flavoring chemical diacetyl; cryptogenic organizing pneumonia and textile dye ("Ardystil syndrome"); and diffuse pulmonary hemorrhage and trimellitic anhydride (142,(145)(146)(147)(148)(149)(150)(151)(152)(153)(154)(155)(156)(157)(158)(159)(160)(161).…”

Occupational Exogenous Lipoid Pneumonia: A Commonly Delayed Diagnosis

“…Finally, there should be an emphasis on the importance of occupational exposure history in patients with non-resolving pneumonia when lipoid pneumonia is suspected. The occupational history should include information about routine tasks performed during a typical work shift and the use of chemicals such as paraffin (11), diesel (4), petroleum jelly, and cutting mist (1). In some cases, patients have limited knowledge of the substances to which they have been exposed.…”

A case of lipoid pneumonia associated with occupational exposure to solvents in a dry‐cleaning worker

“…It is majorly associated with the use of mineral oils, which are a mixture of inert, longchain, saturated hydrocarbons obtained from petroleum [2]. Occupational exposure to these mineral oils is an uncommon cause of lipoid pneumonia [1][2][3]. Moreover, limited data are available on cases of occupational lipoid pneumonia [2,3].…”