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Common Office Tests and Procedures for the Allergist
Published in Pudupakkam K Vedanthan, Harold S Nelson, Shripad N Agashe, PA Mahesh, Rohit Katial, Textbook of Allergy for the Clinician, 2021
There are several published practice parameters for allergen skin testing. Skin testing for the diagnosis of immediate hypersensitivity is performed by one of two methods: percutaneous (prick/puncture) or intradermal. Both methods yield similar information. The intradermal method is more sensitive and reproducible, whereas the percutaneous method is more rapidly performed, less painful and associated with fewer systemic reactions. Consequently, percutaneous testing is usually the preferred initial procedure.
Treatment of Anaphylaxis
Published in Kirsti Kauppinen, Kristiina Alanko, Matti Hannuksela, Howard Maibach, Skin Reactions to Drugs, 2020
Anaphylaxis is an immediate hypersensitivity reaction caused by the activation of a sequence of biochemical mediators. Anaphylaxis is usually an IgE-mediated reaction caused by proteins, polysaccharides, haptens, etc. It may also be caused through complement activation by immune complexes, and some agents cause nonimmunological direct mast cell and basophil degranulation (sometimes called anaphylactoid reactions). The manifestations of anaphylaxis are due to vascular and smooth muscle changes induced by the release of biologically active chemical mediators such as histamine, arachidonic acid metabolites, and factors activating platelets, eosinophils, and neutrophils, e.g., dilatation and increased permeability of small blood vessels resulting in hypotension, contraction of smooth muscle, and attraction of inflammatory cells. Earlier, a common cause of anaphylaxis was the use of diphtheria and tetanus antitoxins. Nowadays, in addition to drugs, the risk of anaphylaxis is connected with diagnostic and desensitizing allergy practices. Penicillin is the most common cause of drug-induced anaphylaxis.3 Drugs and their supposed mechanisms causing anaphylaxis are listed in Table 1.
Role of Nutraceuticals in Atopic Dermatitis, Eczema, Allergy in Pregnancy
Published in Priyanka Bhatt, Maryam Sadat Miraghajani, Sarvadaman Pathak, Yashwant Pathak, Nutraceuticals for Prenatal, Maternal and Offspring’s Nutritional Health, 2019
Meera Ratani, Yasmin Azad, Yashwant Pathak, Priyanka Bhatt
Furthermore, there are two types of allergy:Immediate hypersensitivity: This type of allergy occurs within an hour and is mediated by IgE. When the allergen enters the body, the body mistakes it for a harmful substance and, in the case of immediate hypersensitivity, creates antibodies to fight against the allergen. This is process is known as the sensitization phase of an allergic reaction. Next, in the symptomatic phase, the allergen binds to the IgE located on the mast cell. This “unlocks and opens” the mast cell, which then releases histamines. The histamines trigger the symptoms commonly associated with allergies, such as redness, swelling, and itchiness through vasodilation, increased vascular permeability, and nerve end stimulation respectively. Immediate hypersensitivity is linked to rhinitis and food allergy.Delayed hypersensitivity: This type of allergy takes longer (up to 48 hours) to occur, as suggested by its name, and it is mediated by T cells. Delayed hypersensitivity is linked to contact eczema (EAACI n.d.)
Antibiotic desensitization as a potential tool in antimicrobial stewardship programs: retrospective data analysis and systematic literature review
Published in Expert Review of Anti-infective Therapy, 2022
Alicia Rodríguez-Alarcón, Jaime Barceló-Vidal, Daniel Echeverría-Esnal, Luisa Sorli, Roberto Güerri-Fernández, Sofía Martina Ramis Fernández, Adela Benitez-Cano, Elena Sendra, Inmaculada López Montesinos, Estela Membrilla-Fernández, Olivia Ferrández, Ramón Adalia, Juan Pablo Horcajada, Fernando Escolano, Silvia Gómez-Zorrilla, Santiago Grau
A retrospective study was performed at the Hospital del Mar, a tertiary care university hospital in Barcelona (Spain) from 2015 to 2022. All patients over 18 years of age who had undergone antibiotic desensitization were selected from the pharmacy registry and included. Desensitization was indicated by the responsible physician, in accordance with the ASP. This strategy was reserved for patients with a history of severe allergy or doubtful allergy but at high risk of complications if penicillin-related antibiotics were not administered. Accordingly, desensitization was performed in: a) patients with confirmed allergy and the results of previous positive penicillin skin tests, b) patients with a history of immediate hypersensitivity reactions (including anaphylactic reaction), c) patients with a penicillin allergy label in whom hypersensitivity was not confirmed but who were in a compromised clinical situation and required penicillin or a penicillin-related antibiotic [1].
Allergic reactions to COVID-19 vaccines: statement of the Belgian Society for Allergy and Clinical Immunology (BelSACI)
Published in Acta Clinica Belgica, 2022
Sebastiaan Tuyls, Xavier Van Der Brempt, Margaretha Faber, Romy Gadisseur, Bita Dezfoulian, Rik Schrijvers, Antoine Froidure
Vaccine-associated hypersensitivity reactions are uncommon. Most adverse reactions to vaccines are mild, including local swelling, pain, and localized rash. Those reactions are usually not reproducible when the subject is re-exposed to the vaccine [13]. Of note, local nodules are described in up to 20% of the patients receiving vaccines with an aluminium-based adjuvant. Immunoglobulin (Ig)G-mediated delayed hypersensitivity (Arthus reaction) is rare and provokes a large and severe local reaction, occurring within 72 hours, in sensitized individuals [14]. Immediate hypersensitivity reactions are rare to very rare but are important to identify, given the large number of people vaccinated every year. IgE-mediated allergy may lead to a variety of symptoms, usually occurring within 30 minutes following the injection (and rarely after 4 hours). Symptoms range from urticaria (wheals accompanied with itching and burning) to angioedema (swelling of deeper subcutaneous tissues of the face and throat) and anaphylaxis, the latter two being potentially fatal [15]. Proper recognition of immediate hypersensitivity reactions allows adequate management [16] (see the “Management of suspected anaphylactic reaction” section) and may lead to the identification of the culprit allergen, along with extra precautions for subsequent injections and/or the implication of desensitization protocols. Delayed reactions, occurring in hours or days following the injection, are mostly rashes and are not always immune-mediated.
The Risk Factors of Seasonal Hyperacute Panuveitis
Published in Ophthalmic Epidemiology, 2021
Madan Prasad Upadhyay, Ranju Kharel Sitaula, Anu Manandhar, Emily W. Gower, Pratap Karki, Haramaya Gurung, Indraman Maharjan, Sameul Reuben, Biraj Man Karmacharya, Sagun Narayan Joshi
There are many possible ways in which the moths may cause SHAPU. One possibility is that the moths might serve as vectors, carrying plant material acquired during their feeding time and this material may be the responsible agent that can induce infective and/or immunological reactions within hours of contact. Alternatively, female moth spines and setae bear toxic materials for the natural protection of their eggs. These toxic materials include histamine, acetylcholine, formic acid, venom, pro-inflammatory products of cyclo-oxygenase, and nitric oxide, proteins with trypsin-like activity and vaso-degenerative and fibrinolytic effects, serine proteases and pro-coagulant toxins.15 Some of these venoms and toxins are capable of causing hypersensitivity reactions in susceptible individuals. Some species cause immediate hypersensitivity reactions, others cause delayed-type hypersensitivity, and some appear capable of causing both.4,15,17 Given the rapid onset of SHAPU, type 1 hypersensitivity reaction may be the most plausible explanation as histamine, a mediator of type 1 hypersensitivity is one of the substances that moths carry. Additional research is needed in this area, including the need for toxins & immunobiomarkers analysis of the moth particles and its comparison with the ocular fluid samples of SHAPU.