過敏原皮膚試驗與判讀

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1 過敏原試驗應用與判讀台中榮民總醫院過敏免疫風濕科吳沂達醫師洪維廷醫師陳怡行醫師

2 學習目標 1. 了解過敏原理及其相對應症狀疾病 2. 能正確選擇及開立過敏原檢查 3. 能正確判讀過敏原檢查結果

3 Syllabus 甚麼是過敏過敏之症狀及疾病選擇適當過敏原檢查判讀過敏原檢查結果總結

4 身體對無致病性的蛋白質產生免疫反應

5 Modified Coombs and Gell Classification of Allergic Reactions Kay, A.B. Allergy and Allergic Diseases 2008,3-22.

6 Syllabus 甚麼是過敏過敏之症狀及疾病選擇適當過敏原檢查判讀過敏原檢查結果總結

7 第一型過敏反應 ( 立即型 ) 皮膚發癢, 潮紅蕁麻疹 / 血管性水腫打噴涕 / 流清鼻水 / 鼻塞眼睛癢 / 流眼淚 / 結膜充血水腫支氣管攣縮, 氣喘發作嘔吐, 腹部絞痛, 腹瀉過敏性休克

8 The IgE-dependent allergic inflammation Initial exposure: sensitization IL 4 Th 2 IL 5 IL 13 B Ig E

9 The IgE-dependent allergic inflammation Initial exposure: sensitization Th 2 IL 4 IL 5 IL 13 Re-exposure: allergic reaction FceRI B Ig E Mast cells/basophils

10 第二型過敏反應 (cytotoxic) Allergen- specific IgG 或 IgM 作用在細胞上溶血白血球低下血小板低下 Onset: 不一定

11 第三型過敏反應免疫複合體在組織沉積, 引起補體活化及發炎反應 Serum sickness 發燒皮疹關節痛血管炎淋巴結腫大腎絲球腎炎 Onset : Expose 過敏原 1-3 週後

12 第四型過敏反應過敏性接觸性皮膚炎固定性藥疹 Erythema multiforme Steven-Johnson syndrome Toxic epidermal necrolysis

13 常見過敏病過敏性氣喘過敏性鼻炎 / 過敏性結膜炎異位性皮膚炎過敏性休克蕁麻疹 / 血管性水腫過敏性接觸性皮膚炎食物過敏藥物過敏

14 Syllabus 甚麼是過敏過敏之症狀及疾病選擇適當過敏原檢查判讀過敏原檢查結果總結

15 做什麼檢查? In vivo test Prick-puncture test Intra-dermal skin test Inhalation challenge Oral challenge test Patch test In vitro test Allergen-specific IgE Phadia ImmunoCAP MAST Basophil histamine releasing test Basophil functional test (LTC4, surface marker) HLA B1502; B5801

16 以過敏病的免疫機轉來選定適當的過敏檢查疾病的免疫機轉 Laboratory tests Type I (IgE-mediated) Skin testing (eg. PST), Serum tryptase, Specific IgE Type II (IgG-mediated) Type III (immune complex) Type IV (delayed, cell mediated) Direct or indirect Coomb s test, ANA,anti-platelet Ab, antihistone Ab, AMA, AMiA, etc. ESR, CRP, CIC, C3, C4, CH 50, biopsy Patch test, tuberculin skin test, lymphocyte transformation test

17 過敏原皮膚試驗 Prick-prick test

18 過敏原皮膚試驗 Positive control (histamine 1mg/ml) Negative control (phosphate-buffered saline) Allergen : 20 分鐘後判讀

19 RAST RAST 1 st on the market in 1974, considerable variability & questionable quantification-no longer in use and term is no longer appropriate

20 Allergen Specific IgE Test

21 MAST Multiple allergy-simultaneous test

22 Comparison ImmunoCAP MAST Coating Cellulose sponge (3D) Allergen number 6 36 Sample per test 40uL 1.3ml Paper disc/cellulose thread (2D) 40uL*6=240uL plasma 240uL*3=720uL=0.72ml whole blood

23 Limitation Not golden standard False positive due to non-specific binding Levels of specific IgE depend on age, allergen specificity, total serum IgE, season of year (for inhalant allergens) Cost Delay of time acquiring results

25 When to choose Inhalant allergens Perennial: indoor Seasonal: outdoor Smoking, perfume, air pollutant Asthma/AR/AD/ana phylaxis Food allergen Screening 50% false positive False negative SPT prick-prick test Urticaria/AD/Anaph ylaxis Food additives? Food intolerance?

26 Significance Of Positive Allergy Skin Test Results Food Allergy Diagnostic Testing Pearls, Pitfalls and the Gold Standard Allergy tests yield information on sensitization, which is not always equivalent to clinical allergy. Neither skin or serum sige have 100% sensitivity or specificity The double-blind, placebo-controlled food challenge is the gold standard for food allergies but it is a time-consuming procedure that is limited to trained allergy specialists and 26 carries the risk of producing a severe reaction

27 過敏原貼布試驗 Patch test

28 疾病的免疫機轉 Type I (IgE-mediated) Type II (IgG-mediated) Type III (immune complex) Type IV (delayed, cell mediated) Laboratory tests Skin testing (eg. PST), Serum tryptase, Specific IgE Direct or indirect Coomb s test, ANA,anti-platelet Ab, anti-histone Ab, AMA, AMiA, etc. ESR, CRP, CIC, C3, C4, CH 50, biopsy Patch test, tuberculin skin test, lymphocyte transformation test

29 Syllabus 甚麼是過敏過敏之症狀及疾病選擇適當過敏原檢查判讀過敏原檢查結果總結

30 Skin Prick Test Grade (-) Size (mm x mm) 1+ > Negative control 3mm but <1/2 positive control 2+ ½ but< positive control 3+ =size of positive control ±1mm 2 4+ >positive control with pseudopods

32 Sensitization Reaction

33 In Vitro Tests Semiquantitative classes I-IV or VI Class I and class II: allergen sensitization Classes V and VI: correlate with IgEmediated clinical reactions Latex: Nonzero=positive

34 In Vitro Tests

35 In Vitro Tests Some cross-reactivity may result in clinically irrelevant positive tests Mites, crab, shrimp (avoidance not necessary) Results do not predict severity

37 Molecular allergen test

38 Diagnostic Algorithm

39 Syllabus 甚麼是過敏第一型過敏之症狀及疾病選擇適當過敏原檢查判讀過敏原檢查結果總結

40 Summary Specific IgE levels higher than 0.35 ku/l suggest sensitization, but that is not synonymous with clinical disease The sensitivity of allergy blood tests ranges from 60%-95%, and the specificity ranges from 30%-95% Neither allergy blood testing nor skin testing should be used for screening

43 Thank You Questions and Comments

44 Allergy Skin Testing Advantages & Diagnostic Utility in Comparison to Specific- IgE Antibody SPT may be more sensitive in predicting who will react on challenge In pts with low food sige, SPT may have diagnostic utility SPT can identify sensitivity to labile food proteins

45 Systemic reactions to allergy skin tests Method: Retrospective study at the Mayo Clinic to identify patients who developed systemic reactions to skin tests Results:. 497,656 skin tests were performed : SPT 16,505 patients 6 patients experienced SRs. All had asthma. SPT SR rate was 15 or 23 reactions per 100,000 aeroallergen tests It is noteworthy that there were no systemic reactions to skin tests for foods or venoms Conclusion: SR to skin tests was very low. SRs were mild and all patients recovered fully within 1 hour. 45 Valyasevi et al, Ann Allergy Asthma Immunol 1999;83:

46 Why Skin Testing is Superior to In Vivo Testing Because: More cost and time efficient for patient Results available on initial consultation allowed for development of specific treatment plan Predictive value in terms of presence of clinical allergy and possible severity In some cases greater predictive value than in vivo test Ability to test to allergens that may be altered in extract preparation process e.g., natural foods Can also be used in component-resolved diagnosis

600 现代药物与临床 Drugs & Clinic 第 31 卷第 5 期 2016 年 5 月 were significantly decreased, but the levels of IL-12 in two groups were significantly increa

600 现代药物与临床 Drugs & Clinic 第 31 卷第 5 期 2016 年 5 月 were significantly decreased, but the levels of IL-12 in two groups were significantly increa 现代药物与临床 Drugs & Clinic 第 31 卷第 5 期 2016 年 5 月 599 喘可治注射液联合细辛脑注射液治疗小儿毛细支气管炎的临床研究唐辉英, 佘定平, 马颐娇深圳市儿童医院呼吸科, 广东深圳 518026 摘要 : 目的探讨喘可治注射液联合