allergen immunotherapy 2007-rev1.pptx
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Allergen immunotherapy: A practice parameter second update
Allergen immunotherapy: A practice parametersecond update
J Allergy Clin Immunol 2007
Literature ReadingJeni Arung Padang
Faculty of Medicine Padjadjaran University Dr. Hasan Sadikin General HospitalBandung
1PREFACEDeveloped by the Joint Task Force on Practice Parameters American Academy of Allergy, Asthma and Immunology (AAAAI); the American College of Allergy, Asthma and Immunology (ACAAI); and the Joint Council of Allergy, Asthma and Immunology (JCAAI).Allergen immunotherapy is effective patients with allergic rhinitis, allergic asthma, and stinging insect hypersensitivity.Recommendations safe practice of allergen immunotherapy, prevention and management of systemic reactions.
2PREFACEgood candidates for immunotherapy not controlled adequately by medications and avoidance measures, to avoid the potential adverse effects of medications, and reduce the long-term use of medications.Recommended for patients with a history of systemic reaction to Hymenoptera stings and specic IgE antibodies to Hymenoptera venom.
3ALGORITHM AND ANNOTATIONS FORIMMUNOTHERAPY
4ALGORITHM AND ANNOTATIONS FORIMMUNOTHERAPY
5Box 1Immunotherapy is effective allergic asthma, allergic rhinitis/conjunctivitis, and stinging insect hypersensitivity.Allergen immunotherapy might prevent the development of asthma in individuals with allergic rhinitis. A denitive diagnosis depends on the results of allergy testing (immediate hypersensitivity skin tests or in vitro tests for specic IgE antibody).
6Box 2Immediate hypersensitivity skin testing is generally the preferred method of testing for specic IgE antibodies.Immunotherapy should be considered when positive test results for specic IgE antibodies correlate with suspected triggers and patient exposure.7Box 3Immunotherapy should not be given to :patients with negative test results for specic IgE antibodies.with positive test results for specic IgE antibodies that do not correlate with suspected triggers, clinical symptoms, or exposure.This means that the presence of specic IgE antibodies alone does not necessarily indicate clinical sensitivity.There is no evidence from well-designed studies that immunotherapy for any allergen is effective in the absence of specic IgE antibodies.8Box 4Management of complex medical conditions (allergic asthma, allergic rhinitis/conjunctivitis, and stinging insect hypersensitivity) evaluation of management options. 3 major management approaches (allergen immunotherapy, allergen exposure reduction, and pharmacotherapy).The management plan must be individualized.Disease severity and response (or lack of response) to previous treatment are important factors.9Box 5The physician and patient should discuss the benets, risks, and costs management options and agree on a management plan. Basis of clinical considerations and patient preference.Patients with allergic rhinitis/conjunctivitis or allergic asthma candidat for immunotherapy : - symptoms are not well controlled by medications avoidance measures. - require high medication doses, multiple medications, or both to maintain control of their allergic disease.Asthma must be controlled at the time the immunotherapy injection is administered. In general, patients with stinging insect hypersensitivity who are at risk for anaphylaxis should receive venom immunotherapy (VIT). 10Box 6After careful consideration of appropriate management options the physician and patient might decide not to proceed with immunotherapy.11Box 7Before immunotherapy is started patients should understand its benets, risks, and costs.Counseling include :The efcacy and duration of treatment. Anaphylaxis Adhering to the immunotherapy schedule.12Box 8The physician select allergen extracts on the basis of patients clinical history, allergen exposure history and the results of tests specic IgE antibodies. The physician must specify the starting immunotherapy dose, the target maintenance dose, and the immunotherapy schedule.In general starting immunotherapy dose is 1000-fold to 10,000-fold less than the maintenance dose.For highly sensitive patients, starting dose might be lower. The maintenance dose is generally 1000 to 4000 arbitrary units (AU; eg, for dust mite) or bioequivalent allergy units (BAU; eg, for grass).13Box 8Immunotherapy treatment can be divided into 2 periods, which are commonly referred to as the build-up and maintenance phases.The immunotherapy build-up schedule (also referred to as up-dosing, induction, or the dose-increase phase) entails administration of gradually increasing doses during a period of approximately 14 to 28 weeks.In conventional schedules a single dose increase is given on each visit, and the visit frequency can vary from 1 to 3 times a week.14Box 9Immunotherapy administered in a setting that permits the prompt recognition and management reactions.Patients should wait at least 30 minutes after the immunotherapy injection reactions can be recognized and treated promptly, if they occur.In general immunotherapy injections should be with held if the patient presents with an acute asthma exacerbation.Some physicians recommend providing epinephrine for self-administration in case of severe late reactions to immunotherapy injection.15Box 10Injections of allergen immunotherapy cause local or systemic reactions.Most severe reactions develop within 30 minutes after the immunotherapy injection, but reactions can occur after this time.
16Box 11Local reactions can be managed with local treatment (eg, cool compresses or topical corticosteroids) or antihistamines. Systemic reactions can be mild or severe (anaphylaxis).Epinephrine is the treatment of choice in anaphylaxis intramuscularly or subcutaneous.Antihistamines and systemic corticosteroids are secondary medications systemic reactions but should never replace epinephrine in the treatment of anaphylaxis. 17Box 11The immunotherapy dose and schedule, benets and risks evaluated after any immunotherapy-induced systemic reaction. For some patients the immunotherapy maintenance dose might be reduced because of repeated systemic reactions.The decision to continue immunotherapy should be re-evaluated after severe or repeated systemic reactions to allergen immunotherapy extracts.18Box 12Patients receiving immunotherapy follow-up visits at least every 6 to 12 months, include : a reassessment of symptoms and medication use.the medical history since the previous visit an evaluation clinical response to immunotherapy.There are no specic markers that will predict who will remain in clinical remission after discontinuing effective allergen immunotherapy.
19Box 12Some patients sustain lasting remission of allergic symptoms after discontinuing allergen immunotherapy but others might a recurrence of symptoms after discontinuation of immunotherapy.As with the decision to initiate allergen immunotherapy the decision to discontinue treatment should be individualized Ultimately, the duration of immunotherapy should be individualized based on : patients clinical response, disease severity, immunotherapy reaction history, and patient preference.
20IMMUNOTHERAPY GLOSSARYAllergen immunotherapy extract is dened as the mixture of the manufacturers allergen extract that used for allergen immunotherapy. Allergen immunotherapy the repeated administration of specic allergens to patients with IgE-mediated conditions for the purpose of providing protection against the allergic symptoms and inammatory reactions associated with natural exposure to these allergens.Anaphylaxis is an immediate systemic reaction often occurring within minutes and occasionally as long as an hour or longer after exposure to an allergen.
21The build-up phase involves receiving injections with increasing amounts of the allergen.Cluster immunotherapy is an accelerated build-up schedule that entails administering several injections at in creasing doses (generally 2-3 per visit) sequentially in a single day of treatment on nonconsecutive days. Desensitization is the rapid administration of incremental doses of allergens or medications by which effector cells are renderedless reactive or nonreactive to an IgE-medicated immune response.The effective therapeutic dose or maintenance dose is the dose that provides therapeutic efcacy without significant adverse local or systemic reactions.22Hyposensitization is a term formerly used interchangeably with allergen immunotherapy. Immunotherapy is a treatment modality that appeared soon after adaptive immune responses were discovered and has gradually evolved to encompass any intervention that might benet immune-induced aberrant conditions by a variety of immunologic transformations. The maintenance concentrate is a preparation that contains individual or mixtures of manufacturers allergen extracts intended for allergen immunotherapy treatment.23The maintenance dose (or effective therapeutic dose)is the dose that provides therapeutic efcacy without significant adverse local or systemic reactions.The maintenance goal (or projected effective dose) is the allergen dose projected to provide therapeutic efcacy.The maintenance phase begins when the effective therapeutic dose is reached. A major allergen is an antigen that binds to the IgE sera from 50% or more of a clinically allergic group of patients.24INTRODUCTIONImmunity has been dened as protection against certain diseases.The initial immunotherapeutic interventions, which included the use of preventive vaccines and xenogenic antisera by Jenner, Pasteur, Koch, and von Behring, were effective for disease prevention. Advances in allergen immunotherapy have depended on the improved understanding of IgE-mediated immunologic mechanisms, the characterization of specic antigens and allergens, and the standardization of allergen extracts.