Mastocytosis and the Fig Wasp (Blastophaga psenes)

Mastocytosis involves the abnormal proliferation of mast cells and clinical variability. In the case of anaphylaxis, the triggering antigen, often associated with Hymenoptera allergens, must be identified. The common fig (Ficus carica) requires the fig wasp (Blastophaga psenes) for pollination.

We evaluated the ingestion of B. psenes as a trigger of anaphylaxis in patients with mastocytosis.

Skin prick tests (SPTs) and specific immunoglobulin E to the possible involved allergens were carried out in the patient and in 4 controls allergic to Hymenoptera and fig. Given the possibility of hidden allergens, we studied the source (figs of various origins) and possible hypersensitivity to Hymenoptera allergens, including the fig wasp (B. psenes).

In all subjects, the SPT resulted in a wheal (larger than with histamine) with the extract of the inferior part of the female fig but not with the male extract (lower pole and stem). Immune detection was made with the stem and inferior part of figs and venom of Polistes and Vespula. Recognition bands were observed at 25 kDa with female fig extracts that were also recognized by the patient with anaphylaxis to Hymenoptera venom.

We cannot exclude the possibility that the ingestion of fig with Blastophaga antigens may have triggered anaphylaxis in our patient.