CROSS-REACTIVITY BETWEEN FICUS-BENJAMINA (WEEPING FIG) AND NATURAL-RUBBER LATEX

The importance of hypersensitivity to Ficus allergens is reported. Cro ss-sensitization between fig (Ficus carica), weeping fig (F. benjamina [Fb]), and natural rubber latex (NRL) was confirmed by RAST inhibitio n. We performed skin prick tests with fresh Fb tree sap and NRL extrac ts in 346 consecutive patients and in 151 patients with immediate-type hypersensitivity to NRL. Total serum IgE and IgE antibodies to NRL an d Ficus spp. were analyzed in sera. By the RAST-inhibition method, we studied cross-reactivity among latex, fig, and weeping fig. Sensitizat ion to Fb was diagnosed in 23 of the 346 consecutive patients, and the simultaneous presence of latex-specific IgE was highly significant. O f 151 NRL-allergic patients, 35 were also sensitized to Fb. Cross-reac ting IgE antibodies recognizing latex and Ficus allergens were demonst rated by RAST inhibition. The present study reinforces the importance of Fb as an indoor allergen. Cross-reacting IgE antibodies to NRL and Ficus spp, allergens are frequently found in the sera of atopic patien ts. Development of commercially available standardized extracts for sk in tests is urgently necessary.