D1.36 - Prevalence of thaumatin and Alternaria co-sensitization

Thaumatin like proteins (TLP) are defense proteins that are significantly expressed in plants and fruits affected by pathogenic infections, especially those caused by fungi such as Alternaria. Thus, there may be a possible co-sensitization between Alternaria and thaumatin. Currently, the clinical implications of these proteins are partially known.

Study the in vitro co-sensitization between thaumatin and Alternaria and its association with clinical symptoms.

A descriptive, observational, and retrospective study was conducted on samples of patients with positive results for specific IgE to kiwi TLP (Act d 2) and/or Alternaria (Alt a 1) seen between 2020 and 2024 at the Allergy Service of the Hospital Universitario y Politécnico La Fe (Valencia, Spain). Samples were analyzed using the multiplex diagnostic platform (ImmonoCAP© ISAC 112) and clinical information from the hospital's electronic records (ORION Clinic ®).

Seven hundred and fifty-two samples were included in the study, Seventy-three (9.7%) showed positive results at least from Act d 2 and/or Alt a 1. Fifty-four (74%) of these samples were positive for both Act d 2 and Alt a 1. In this group, 46 (85.2%) patients were diagnosed with respiratory allergy, and 9 (16.6%) with digestive symptoms. Eight patients (15%) showed food-related anaphylaxis, mainly associated with banana consumption (33%). The prevalence of food anaphylaxis was higher in patients with sIgE Act d 2 > sIgE Alt a 1 (16.17% vs 10.2%; p=0.22). In patients with food anaphylaxis, the main clinical symptom was eyelid angioedema.

See Table1. 

Seventy-four percent of patients sensitized to Act d 2 are co-sensitized with Alt a 1. Regardless of the IgE levels of Alt a 1 and Act d 2, the predominant clinical presentation is respiratory. However, in the group of patients with Act d 2 > Alt a 1, a slight increase in the incidence of anaphylaxis is observed (16.17% vs 10.2%). The food most frequently associated with anaphylaxis in these patients was banana, and the most frequent clinical manifestation was periorbital angioedema