第一次来我们过敏门诊时，女孩的母亲给我们看了一个ISAC (Immuno Solid-phase Allergen Chip)试验，操作特异性IgE检测的同事建议得到更清晰的变态反应结果。这次试验结果显示，对尘螨、榛子、桦树和草花粉中度阳性，对Jugr3中度阳性，对Cora1只是轻度阳性。其它所有的花生和树坚果过敏原均阴性。榛子花粉点刺（阳性，5mm）,榛子提取物点刺试验结果阴性。因此，进行了榛子的食物激发试验，没有出现即刻反应。从此，食用榛子均无出现任何异常。
Clinical and Translation alAllergy
Case Report: Revaluation of a previously diagnosed hazelnut allergy with component resolved diagnosis (CRD)
We report a case of an eleven years old girl who was referred to our Allergy Outpatient Clinic for the revaluation of a hazelnut allergy. During her infancy she was successfully desensitised to milk and egg. Afterward she had been followed by another Allergy Unit where, according to skin prick test and specific IgE dosage, it had been suggested to strictly avoid peanut and all treenuts, although clinical history was not suggestive of treenuts allergy. She was also provided with an auto-injectable adrenaline, due to the high risk of severe reactions to treenuts. No oral provocation test was performed to validate diagnosis and adrenaline prescription.
Methods and Results
At her first visit in our Allergy Outpatient Clinic, the girl's mother showed us an ISAC (Immuno Solid-phase Allergen Chip) test, suggested by the colleague who performed the specific IgE dosage to better clarify the allergological results. On this test, a moderate positivity to dust mites, hazel, birch and grass pollen, a moderate positivity to Jugr3 and only a mild positivity to Cora1 were identified. All other peanuts and treenuts allergens were negative. A prick test for hazel pollen (positive, 5 mm) was performed; hazelnut extract , hazelnut with prick-by-prick method all resulted negative. Therefore an oral provocation test was performed with hazelnut and no immediate reactions were observed. In the following days she ate hazelnut without any symptoms.
In this case-report we highlight the important role of CRD in the diagnosis of hazelnut allergy. Moreover, we underline the importance of a correct diagnosis of food allergy which has to rely not only on specific IgE dosage or skin prick test, but should be confirmed by an oral provocation test.