2018 Volume 121 Issue 12 Pages 1493-1498
Cross reactivity has been observed between Japanese cedar pollen (JCP) and tomato extract, because of the presence of common epitopes. Because the oral mucosa is directly exposed to the allergen during sublingual immunotherapy (SLIT), we considered that SLIT with Japanese cedar pollen might have some influence on the allergic reactions to tomato antigens in patients with tomato oral allergy syndrome (OAS).
We studied the influence of JCP SLIT in subjects with tomato OAS.
The adverse events in 220 cases of JCP SLIT during the first year were recorded. In 107 of these cases, changes in the s-IgE in 107 were followed up for 2 years. We clinically identified two patients of tomato OAS among our 455 JCP SLIT experiences.
No increase in the frequency of adverse events was observed in the groups with class 2 (20 cases of SLIT) and 1 (18 cases of SLIT) immuno-CAP scores, as compared to that in those with class 0 (182 cases of SLIT) scores. On average, the serum tomato s-IgE level was 0.16±0.16 in the pre-SLIT phase, 0.18±0.19 at 1 year after the treatment, and 0.16±0.16 UA/mL at 2 years after the treatment. Among the 92 class 0 cases, class 0 increased to class 1 in 10 cases, and to class 2 in 4 cases after 1 year. Furthermore, the s-IgE level in 12 class 0 cases increased from under the detectable range (<0.1UA/mL) to over the detectable range. In all, the s-IgE increased in 37% the cases after 1 year, if cases with only a slight increase were included. The two patients with tomato OAS who underwent SLIT were maintained without any trouble. The cross-reactivity of epitopes between JCP and tomato may cause increase in the serum levels of tomato s-IgE during JCP SLIT, because similar changes of the the tomato and JCP s-IgE levels were observed.
JCP SLIT can be performed safely in patients positive for tomato s-IgE, based on our experience.
