Clinical Application of Beryllium Lymphocyte Proliferation Testing

Abstract

Beryllium is a lightweight metal with unique properties that render it ideal for use in nuclear, aerospace, electronics, ceramics, and metallurgy industries. Up to 5% of beryllium-exposed individuals develop CBD, a granulomatous disorder characterized by T-lymphocyte-mediated hypersensitivity to beryllium. Although CBD is clinically indistinguishable from sarcoidosis, the BE-LPT provides a means for differential diagnosis. A positive blood BE-LPT is specific for beryllium hypersensitivity, which may be associated with CBD (subclinical or overt) at the time of testing. As a follow-up step, individuals may undergo pulmonary evaluation, including bronchoscopy, transbronchial biopsy, BAL, and BAL BE-LPT. There is some evidence that the sensitivity of the BE-LPT for CBD is higher in BAL than in blood, but both tests show some variability, and histopathologic verification of granulomas is required for CBD diagnosis. Genetic analyses have shown an association of HLA-DPB1Glu69 (a relatively common phenotype within the general population) with CBD. Further studies are needed to continue to elucidate beryllium hypersensitivity and CBD on the molecular level.