The paper concerns some aspects of differential diagnosis of allergic occupational diseases.  The definition of occupational disease and principles of diagnosis of occupational diseases are presented in this article and the diagnostic methods in occupational allergic diseases are also discussed. The main legal regulations regarding occupational diseases are briefly described.

Diagnostic and differential diagnosis of occupational allergic diseases is to establish a diagnosis of diseas and to demonstrate its occupational etiology. Differential algorithm progress in stages, so brings closer the final, the correct diagnosis. In the first stage, the main effort should be directed to the exclusion of diseases with similar clinical picture, and putting accurate diagnosis. The next step will be to demonstrate a sensitization or reaction non-immunological responding to a factor present in the work environment. This means that an employee signs a statement corresponding to the image of disease caused by the analyzed factor.

The last step in the differential diagnosis of occupational diseases is to confirm certain or highly probable (bordering on certainty) one relation between the action factor at the workplace and the development and course of the syndrome found for the employee.