Department of Woman and Child Health, Policlinico Gemelli Universitary Foundation IRCCS, Catholic University of Sacre Hearth, Rome 00168, Italy;.
Department of Woman and Child Health, Policlinico Gemelli Universitary Foundation IRCCS, Catholic University of Sacre Hearth, Rome 00168, Italy.
Acta Biomed. 2021 Apr 30;92(S1):e2021067. doi: 10.23750/abm.v92iS1.10043.
Diagnosis of walnut allergy includes the evaluation of IgE sensitization by skin prick tests (SPT) with standardized commercial extracts. When assuming the loss of relevant allergens due to extract preparation and storage, it is possible to perform SPT with fresh foods, i.e., prick by prick (PbP). To our knowledge, there is no published comparison between SPT with commercial extracts and PbP with fresh food about their sensitivity to the diagnosis of walnut allergy. Therefore, we describe our experience.
We observed seven children (mean age + SD 6.8 years + 5.2, range 2 - 15 years; male 85%) with an history of immediate adverse reaction following walnut ingestion. All but one the patients underwent SPT with at least two out of three walnut commercial extracts (Lofarma, Milan, Italy; ALK-Abellò, Milan, Italy; Allergopharma, Rome, Italy). It has also been performed PbP with raw walnut. IgE-mediated walnut allergy was diagnosed based on suggestive history, positivity of PbP and failed open food challenge with walnut.
The SPT with Lofarma extract was never positive (sensitivity = 0%), that performed with ALK extract was positive in 2/5 cases (sensitivity 40%) and that of Allergopharma extract was positive in 1/5 cases (sensitivity 20%). PbP was positive in 7/7 cases (sensitivity 100%).
In the specific case of walnut allergy in pediatric age, the execution of SPT alone with commercial extract may not be sufficient and clarifying in the diagnostic iter. We suggest to always associate the execution of PbP test.
诊断胡桃过敏包括通过皮试（SPT）评估 IgE 致敏，使用标准化商业提取物。假设由于提取物的制备和储存而导致相关过敏原丢失，可以使用新鲜食物进行 SPT，即逐点刺（PbP）。据我们所知，尚无关于商业提取物 SPT 和新鲜食物 PbP 对胡桃过敏诊断的敏感性的比较发表。因此，我们描述了我们的经验。
我们观察了七名（平均年龄+标准差 6.8 岁+5.2 岁，范围 2-15 岁；男性 85%）有胡桃摄入后立即不良反应史的儿童。除一名患者外，所有患者均接受了至少两种商业胡桃提取物（Lofarma，米兰，意大利；ALK-Abellò，米兰，意大利；Allergopharma，罗马，意大利）的 SPT。还进行了生胡桃的 PbP。根据提示性病史、PbP 阳性和开放食物挑战胡桃失败，诊断为 IgE 介导的胡桃过敏。
Lofarma 提取物的 SPT 从未阳性（敏感性=0%），ALK 提取物的 SPT 阳性率为 2/5（敏感性 40%），Allergopharma 提取物的 SPT 阳性率为 1/5（敏感性 20%）。PbP 阳性率为 7/7（敏感性 100%）。
在儿童期特定的胡桃过敏情况下，单独使用商业提取物进行 SPT 可能不足以明确诊断。我们建议始终联合执行 PbP 检测。
