202111260941新冠疫苗相關的遲發性過敏反應COVID-19: Allergic reactions to SARS-CoV-2 vaccines
參考資料 uptodate, 文獻回顧至2021年10 月
Delayed reactions — Other types of reactions reported with the mRNA COVID-19 vaccines include delayed urticarial reactions, late local reactions, and swelling at the site of dermal fillers.
allergic reaction An allergic reaction may be defined as an idiosyncratic reaction that is caused by an immunologic mechanism.
non-IgE mediated mast cell degranulation
cytokines 細胞激素, 細胞因子
allergen immunotherapy 過敏原免疫療法
遲發性蕁麻疹. 有些人在接種疫苗數小時至數日後發生蕁麻疹或輕微血管性浮腫, 多數嚴重全身性過敏反應案例報告都是在接種後 30分鐘內發生(絕大多數是 15 分鐘內).
Delayed urticarial reactions — Occasionally, patients develop a few hives and/or mild angioedema several hours or days after administration, as with other vaccines. In contrast, the vast majority of the reported potentially serious systemic allergic reactions to the mRNA COVID-19 vaccines have occurred within 30 minutes of vaccination (most within 15 minutes). Hives and/or angioedema that develop hours or days later are exceedingly unlikely to represent an allergic reaction to the vaccine. Rather, this time course corresponds to the beginning of the normal immune/inflammatory response to an immunization, which may include the generation of cytokines or other factors that lead to non-IgE-mediated mast cell degranulation. As such, we do not believe that patients who develop hives or other mild symptoms more than two hours after vaccination require additional evaluation. Rather, we recommend that they receive their second vaccine dose on time in the usual manner but take a nonsedating antihistamine one hour before and be observed for 30 minutes after vaccination. This approach is often used for allergen immunotherapy and is unlikely to mask or delay the recognition of a serious allergic reaction.
遲發性局部反應. 較常發生於接種第一劑莫德納疫苗之後, 但其他疫苗也有類似案例(AZ)
Late local reactions — In addition to the common injection site reactions that may involve some combination of pain, redness, and swelling, and typically occur within a day or two of vaccination, late-onset injection site reactions have also been observed, mostly after first doses of the Moderna vaccine, but also after the ChAdOx1n CoV-19 (AstraZeneca/Oxford) vaccine . In a series of 12 patients, late local reactions developed a median onset of day 8 after vaccination and resolved over a median of 6 days . Features included a fairly well-demarcated area of erythema, often accompanied by swelling and tenderness (picture 1). Some reactions have an overlying dermatitis. A second series of 12 patients with such reactions describes similar nature, onset, and duration . The timing coincides with what is likely a robust local humoral and cellular immune response to the spike protein being generated by the vaccine mRNA at the injection site. Systemic symptoms are variable. Although such reactions could mimic cellulitis, infection after vaccination is uncommon.
Late local reactions typically resolve without treatment other than ice or an analgesic if they are painful or an antihistamine if they are pruritic. Although systemic corticosteroids would likely hasten their resolution, they might also interfere with the immune response. Topical corticosteroids might be helpful and are unlikely to interfere with immunologic responses. We have recommended that patients with such reactions receive their second dose in the usual manner on time, but in the opposite arm. There have been no recurrences of late onset local reactions, but a minority of patients report similar but early-onset local reactions to their second doses [40,41]. The timing of these possible recurrences makes them difficult to distinguish from the more common injection site reactions that occur within a day or two of first or second vaccine doses. The mechanism of these reactions is unclear; biopsy of one such lesion was consistent with delayed-type hypersensitivity , although it is unclear why the reactions would tend not to recur if this were the mechanism .
Swelling at site of dermal fillers — Facial swelling in areas previously injected with cosmetic dermal fillers has been reported following receipt of the Moderna vaccine. The pathophysiology is not yet clear, but local inflammation and fluid retention are proposed to play a role. These reactions are discussed separately. (See "COVID-19: Cutaneous manifestations and issues related to dermatologic care", section on 'Soft tissue fillers'.)