GM‐CSF antibodies in artificial stone associated silicoproteinosis: A case report and literature review

Pulmonary alveolar proteinosis (PAP) is a rare lung disease where there is accumulation of surfactant in the alveoli. It can be classified based on the underlying aetiology into three categories: primary, secondary and congenital. Autoantibodies to granulocyte‐macrophage colony‐stimulating factor (GM‐CSF‐Ab) are a key diagnostic feature of autoimmune PAP. High intensity occupational exposure and inhalation of toxic particles such as silica can cause a form of secondary PAP called acute silicoproteinosis. We describe a 26‐year‐old stone benchtop fabricator with silicoproteinosis following daily exposure to high levels of silica who had elevated serum GM‐CSF‐Ab. We discuss the role of GM‐CSF‐Ab in cases of PAP with occupational inhalational exposure and the challenges in its interpretation.