[Diagnosis of occupational skin diseases].

Occupational skin diseases (mainly irritative and allergic contact dermatitis) are a significant part of occupational diseases. The economical burden of occupational skin diseases (OSD) is huge comprising direct costs (treatment, compensation) as well as indirect costs due to sick leave and lack of productivity. The management of a case of OSD is complex requiring different steps ranging from diagnosis to prevention, through interpretation of patch tests and outpatient treatment and involving an interdisciplinary approach. Patch tests alone cannot prove the allergic origin of OSD because positive results can be referred to a previous contact dermatitis and negative ones may simply be apparent.