Positive skin and oral challenge responses to potato and occurrence of immunoglobulin E antibodies to patatin (Sol t 1) in infants with atopic dermatitis

The clinical significance and molecular specificity of hypersensitivity rea ctions to raw and cooked potatoes remain ambiguous. We therefore investigat ed the clinical hypersensitivity to raw and cooked potato in infants suspec ted to have potato allergy and compared the findings with the occurrence of immunoglobulin E (IgE) antibodies to patatin (Sol t 1), characterized as t he primary allergen of potato. Twelve infants (10 to 24 months of age) suff ering from atopic dermatitis (AD) and suspected to have adverse reactions t o potato, were examined. As a skin exposure test we used rubbing with both raw and cooked potato, and used open oral challenge with cooked potato for 7 days. A special eczema scoring system (SCORAD) was used to assess the sev erity of symptoms and signs of AD. Skin-prick tests (SPTs) were performed w ith raw potato and natural Sol t 1, and serological studies included measur ement of total serum IgE and IgE antibodies to Sol t 1, and potato radioall ergosorbent testing (RAST). The skin-rubbing test with raw potato was posit ive in seven (58%) and the oral challenge positive in eight (67%) infants. One infant presented with an immediate reaction and seven with a delayed re action, i.e. exacerbation of AD, after oral challenge responses to cooked p otato. Nine (75%) infants had IgE antibodies to Sol t 1 in enzyme-linked im munosorbent assay (ELISA), and SPT to natural Sol t 1 was positive in six ( 50%) potato-allergic infants. In conclusion, we observed positive challenge responses to both raw and cooked potato in food-allergic atopic infants. T he presence of IgE antibodies and concomitant positive SPTs to the heat-sta ble potato allergen, Sol t 1, suggest that cooked potato can be an allergen ic food for infants suffering from AD.