Occupational sensitization to Plasmopara viticola.

Molds of the class of Oomycetes are of allergologic importance in special cases. However, probes are not commercially available for diagnostic purposes. Our case report is based on the medical history of a greenhouse worker who had atopic syndrome. He handled pure cultures of defined fungi and plants. A sensitization to pseudo mildew growing on grapevine (Plasmopara viticola) was found. Skin prick test and histamine release test results were positive when extract of P. viticola was used. Detection of IgE reactivities against pseudo mildew via binding tests, Western blot analysis, and isoelectric focusing immunoblot confirmed the diagnosis. To our knowledge these results demonstrate for the second time a sensitization to Oomycetes.