[Immunological aspects of workers exposed to the risk of silicogenesis]

Comparative studies were performed, of changes of serum proteins and IgG, IgA and IgM immunoglobulins in workers exposed to silicogenic dust. Depending on their response to tuberculin testing (2 U of PPD) these subjects were classified in negative and hyperergic. In both groups there was found a decreased albumin concentration in the serum and high alpha-2 globulin. In hyperergic subjects there was noted a slight increase of beta globulins and a significant rise in the titer of gammaglobulins. Immunoglobulins G showed a significant rise in hyperallergic subjects and slightly decreased in tuberculin negative ones, without attaining a level of immunologic deficiency. In both groups IgM immunoglobulins were significantly lowered, while IgA immunoglobulins were occasionally increased, although there was no positive correlation with tuberculin allergy. In three cases there was a slight IgA deficiency.