Oral fluid peroxidase activity increase responsive to apple juice in patients with positive priñk-prick test
Vitebsk State Medical University
Purpose. Diagnosis of an allergy to apples by assessing the peroxidase activity of oral fluid (PAOF) after an oral-pharyngeal test with freshly prepared apple juice and a priñk-prick test.
Materials and methods. 27 patients with clinical intolerance to fresh apples and birch pollen and 28 healthy volunteers were examined. All subjects underwent an open provocative oral-pharyngeal test with freshly prepared Golden Delisious apple juice, followed by spectrophotometric evaluation of PAOF. The prick-prick test was performed to all participants with fresh apples of the Golden Delicious and Red Prince varieties.
Results. 78% of patients with food allergies to apples showed a significant PAOF level increase Me=40.9 (18.9;69.1)%, compared with the control group M=3.2 [-1.2;7.6]%, (p=0.00001). In the control group, PAOF level increase +23.4% was recorded in 1 case (4%). The prick-prick test with Golden Delicious and Red Prince apples were positive in 96% of patients. The skin reaction to Red Prince is more pronounced on the peel Me = 400.0 (110;470) mm2 than on the flesh Me=391.5 (95.6;465) mm2, (p=0.038). The area of skin reaction to the peel (p=0.004) and flesh (p=0.001) is significantly larger on the Red Prince apple than on the Golden Delicious. A correlation was found between the size of skin blisters after scarification tests with birch pollen allergen and a prick-prick test with 2 varieties of apples (r1=0.71, r2=0.69).
Findings. Cross food allergy to apples, established using the prick-prick test with fresh apples (in 96% of cases), was confirmed by a provocative oral-pharyngeal test with determination of PAOF level in 74% of cases. PAOF level increase in combination with the positive prick-prick test was found in most patients allergic to apples, which makes it possible to use these methods together. In patients with food allergy to apples, PAOF level increase after the provocation test is significantly higher than in healthy volunteers (p=0.000001). Sensitization is more pronounced for red apples (Red Prince) than for green apples (Golden Delicious).