[Chronic beryllium disease: a model of interaction between environmental exposure and genetic predisposition. Pathogenesis and clinical features (Part 2)].
BACKGROUND
Chronic beryllium disease (CBD) is an occupational lung disease caused by the inhalation of beryllium dust, fumes or metallic salts.


METHODS
Beryllium affects the lungs via particles deposited in the pulmonary alveoli. These are ingested by alveolar macrophages which act as antigen presenting cells to CD4+ T lymphocytes. T lymphocytes proliferate in response to beryllium antigens and combined with macrophages produce numerous epithelioid granulomas with the release of inflammatory cytokines (IFNgamma, IL-2, TNFalpha and IL6) and growth factors. Beryllium induces macrophage apoptosis which reduces its clearance from the lung which in turn contributes to the host's continual re-exposure and thus a chronic granulomatous disorder. Pulmonary granulomatous inflammation is the primary manifestation of CBD, but the disease occasionally involves other organs such as the liver, spleen, lymph nodes and bone marrow. The clinical, radiological, and histopathological features of CBD can be difficult to distinguish from sarcoidosis. The Beryllium lymphocyte proliferation test (BeLPT) demonstrates a beryllium specific immune response, confirms the diagnosis of CBD, and excludes sarcoidosis.


CONCLUSIONS
CBD provides a human model of pulmonary granulomatous disease produced by an occupational exposure, occurring more frequently in those with a genetic pre-disposition. It can be differentiated from sarcoidosis by specific immunological testing.
Marchand-Adam
S
S
Service de Pneumologie, Hôpital Avicenne et EA 2363, UFR SMBH, Bobigny, France.
Guillon
F
F
Brauner
M
M
Valeyre
D
D
D001607:Berylliosis / Q000175:diagnosis* / Q000209:etiology* / Q000235:genetics / Q000276:immunology / Q000628:therapy; D002908:Chronic Disease; D004781:Environmental Exposure; D020022:Genetic Predisposition to Disease; D006801:Humans; D008962:Models, Theoretical