Pollen of Parietaria officinalis causes season-associated respiratory symptoms. In Southern Croatia (Yugoslavia) we found 65% patients with rhinitis and/or asthma to be allergic to this pollen. They showed positive cutaneous reactions and had specific IgE antibodies to the respective isolated allergen. The finding represents the first report on Parietaria officinalis-induced allergy on the east Adriatic coast.

The levels of IgE antibodies specific for toluene-diisocyanate (TDI), diphenylmethane-diisocyanate (MDI) and hexamethylene-diisocyanate (HDI) were determined in eight workers with an unequivocal history of professional asthma, all having been exposed to isocyanates in the working atmosphere. Five workers were examined at the clinical onset of asthma. They had serum IgE antibodies specific for TDI, MDI and HDI, and depressed pulmonary ventilation parameters. In contrast, three workers, who had only a mild bronchial obstruction at the time of testing, had no anti-isocyanate IgE antibodies. The results indicated that asthma was induced by type I allergic reaction, but other pathogenetic mechanisms of bronchoobstruction could not be completely ruled out.

Hypersensitivity to Parietaria officinalis (wall pellitory) pollen and other environmental allergens was studied in pollinosis patients allergic to P. officinalis pollen who were born in areas without P. officinalis and later moved to the city of Split, where P. officinalis is responsible for some 65% of pollinosis cases. Highly significant positive correlations were found for both the intensity of skin test reaction and concentration of specific serum IgE with the length of residence in the area. In contrast, the respective data on subjects hypersensitive to P. officinalis pollen allergen, but born and living in the area of Split, revealed a tendency to negative correlation between age and intensity of hypersensitivity to P. officinalis. A number of patients from both groups were tested for presence of serum IgE antibodies specific for 14 common environmental allergens. Hypersensitivity to P. officinalis pollen was associated with hypersensitivity to olive, mugwort, and birch pollen in newcomers; hypersensitivity to birch and, to some extent, olive pollen was significantly more frequent in newcomers than in autochthonous patients who were allergic to P. officinalis pollen. Regardless of whether the patients were autochthons or newcomers to the area with P. officinalis, hypersensitivity to P. officinalis mostly excluded hypersensitivity to Dermatophagoides farinae and D. pteronyssinus, and vice versa.