ß-Blockers and angiotensin-converting enzyme inhibitors with sublingual immunotherapy: are risks related to individual product safety profile?

PURPOSE OF REVIEW: The objective of this article is to review the available literature regarding the risks associated with sublingual immunotherapy and angiotensin-converting enzyme (ACE) inhibitors or ß-blocker use. It also evaluates for any differences in these risks among the available sublingual immunotherapy (SLIT) tablets. RECENT FINDINGS: A literature search was conducted in PubMed to identify peer-reviewed articles using the following keywords: anaphylaxis, ACE inhibitor, ß-blocker, and sublingual immunotherapy. Minimal data exist regarding their safety of SLIT in patients concomitantly taking ACE inhibitors or ß-blockers. The adverse reaction rates seem similar between SLIT products. SUMMARY: A risk-versus-benefit discussion should be communicated with the patient taking a ß-blocker before beginning SLIT but automatic denial of SLIT to these patients is not warranted.

Sublingual Immunotherapy for Other Indications: Venom Large Local, Latex, Atopic Dermatitis, and Food.

There is some evidence to support the use of sublingual immunotherapy (SLIT) in food allergy, although its role is unclear. One randomized, double-blind, placebo-controlled trial supports the safe and efficacious use of dust mite SLIT in children with mild to moderate atopic dermatitis, but these data have not been confirmed. Although there are several randomized, double-blind, placebo-controlled trials to support the use of SLIT-LATEX, this product is not available in the United States and extrapolation of these effects to latex extracts is unsubstantiated. There is also insufficient evidence to support the use of SLIT for venom hypersensitivity at this time.

Are ACE Inhibitors and Beta-blockers Dangerous in Patients at Risk for Anaphylaxis?

The objective of this article is to review the available studies regarding angiotensin converting enzyme (ACE) inhibitors and beta-blockers and their effect on patients at risk for anaphylaxis. A literature search was conducted in PUBMED to identify peer-reviewed articles using the following keywords: anaphylaxis, ACE inhibitor, beta-blocker, food allergy, radiocontrast media, venom allergy, skin testing, and immunotherapy. Some studies show an increased risk of anaphylaxis in patients who are taking ACE inhibitors and beta-blockers, whereas others studies do not show an increased risk. For venom immunotherapy, there are more data supporting the concomitant use of beta-blockers and ACE inhibitors in the build-up and maintenance phases. Most of the medical literature is limited to case reports and retrospective data. Prospective controlled trials are needed on this important topic. For those patients at risk of anaphylaxis who lack cardiovascular disease, it is recommended to avoid beta-blockers and possibly ACE inhibitors. However, for those patients with cardiovascular disease, beta-blockers and ACE inhibitors have been shown to increase life expectancy. Consideration should be given for the concomitant use of these medications while patients are receiving venom immunotherapy.

ABAI's MOC Assessment of Knowledge Program Matures: Adding Value with Continuous Learning and Assessment.

Rapid changes in modern medicine along with advances in the science of learning and memory have necessitated a shift in the way physician knowledge is assessed. Physician recertification beyond initial certification has historically consisted of retaining large amounts of knowledge over a long time span. The adult learning theory has shown that the maintenance and improvement of our knowledge base is more effective by being exposed to new concepts at regular intervals throughout one's career and reinforcing these concepts on an ongoing basis. These philosophies have spurred several American Board of Medical Specialties member boards to embark on a variety of continuous assessment models that are designed to keep physicians up to date with the use of new technologies and innovative and flexible question formats. This article describes the new American Board of Allergy and Immunology (ABAI) Continuous Assessment Program. As the ABAI departs from the traditional secure examination/test center model and embarks on its new pilot, the focus remains firmly rooted in the core competencies that patients and the public demand and deserve. Through surveys, the ABAI has laid the groundwork for initial program design by asking its diplomates to rank the most relevant aspects of a sound clinical assessment. Periodic surveys to follow will enable the ABAI to adjust program design to provide the most pertinent content to practicing physicians to improve patient care, promote professionalism, and ensure public trust.

Cross-reactivity between allergens in the venom of the common striped scorpion and the imported fire ant.

BACKGROUND: The common striped scorpion, Centruroides vittatus, and the imported fire ant (IFA) are endemic to the south-central United States. There is evidence of venom-specific IgE in patients experiencing hypersensitivity reactions to scorpion stings. The infrequency of repeated scorpion stings and the presence of immediate reactions to an initial sting suggest prior sensitization. OBJECTIVE: In the present study we evaluated the cross-reactivity of C vittatus venom with IFA whole-body extract (WBE). METHODS: Sera were obtained from patients with symptoms of immediate hypersensitivity to C vittatus stings and from scorpion sting-naive patients allergic to IFA venom. Inhibition IgE immunoblots were performed by using scorpion venom and IFA WBE. Skin testing with scorpion venom was performed on scorpion sting-naive patients allergic to IFA venom. RESULTS: Sera from patients with scorpion venom allergy demonstrated IgE binding to multiple allergens of similar sizes against both scorpion venom and IFA WBE. This binding was completely inhibited by preincubation of the sera with scorpion venom and IFA WBE. Pooled sera from patients with IFA venom allergy demonstrated similar bands on IgE immunoblotting against both IFA WBE and scorpion venom, with the latter being completely inhibited by preincubation of the sera with IFA WBE. Skin testing with scorpion venom was positive in 6 of 9 patients with IFA venom allergy. CONCLUSION: Significant cross-reactivity exists between the venom of C vittatus and IFA WBE. The high sensitization rate to IFA venom in endemic areas may therefore be a risk factor for subsequent immediate reactions to an initial scorpion sting. Patients with immediate hypersensitivity reactions to scorpion stings may potentially benefit from immunotherapy with IFA WBE.

Negative venom skin test results in patients with histories of systemic reaction to a sting.

For more than 20 years venom immunotherapy has been the preferred treatment for Hymenoptera allergy and venom skin testing the preferred diagnostic test. Most allergists consider venom skin tests to be highly accurate and interpret a negative venom skin test result to indicate the absence of insect allergy. Furthermore, current practice guidelines do not adequately address the question of how best to manage the patient with a convincing history of insect allergy but negative skin test results. Recent case reports and published studies have forced us to reexamine this important management issue and to consider what role in vitro venom testing might have in the management of insect allergy. We reviewed the current status of what is known about the management of individuals with a history of insect allergy but negative venom skin test results and suggested modifications of current working guidelines.

Determination of the incidence of sensitization after penicillin skin testing.

BACKGROUND: Concerns for sensitization after penicillin skin testing are a factor in limiting the timing and population for whom this testing is offered. The sensitizing potential of the penicillin skin test has never been studied directly. METHODS: A total of 329 volunteers underwent prick and intradermal skin testing with penicillin G, benzylpenicilloyl-polylysine, and a minor determinant mixture. Those with negative skin testing had repeat testing 4 weeks later. Medical history and antibiotic use were determined by interview, questionnaire, and electronic pharmacy records. RESULTS: Seventy-two of the 329 subjects (22%) reported a history of previous beta-lactam reaction, of which 10 (14%) had a positive initial skin test. Overall, the initial skin test was positive in 23 of 329 (7%). Of the subjects with a negative initial skin test, 239 completed the second test 4 weeks later. Of these, 6 subjects (2.5%, 95% confidence interval 0.5% to 4.5%) converted to a positive skin test. None had taken a beta-lactam antibiotic between the two tests, and none had any previous history of beta-lactam reaction. One subject reported having never taken a beta-lactam antibiotic before. In comparison to the 233 subjects who did not convert their skin test, the statistically significant factors favoring sensitization were: female sex (odds ratio [OR] 6.53, P = 0.05), atopy (OR 5.31, P = 0.04), and history of food allergy (OR 6.35, P = 0.02). There was a trend toward more recent penicillin use in the newly sensitized subjects, but this was not statistically significant.. CONCLUSION: Penicillin skin testing may sensitize a small number of individuals to penicillin.

Safety and efficacy of an imported fire ant rush immunotherapy protocol with and without prophylactic treatment.

BACKGROUND: Hypersensitivity to the sting of the imported fire ant (IFA) is a growing and significant cause of morbidity and mortality in the United States. Conventional immunotherapy with IFA whole body extract (WBE) has been shown to be effective; however, rush immunotherapy (RIT) with IFA WBE has not been studied. OBJECTIVE: In this study, we evaluated the safety and efficacy of RIT with IFA WBE and sought to determine whether prophylactic pretreatment with antihistamines and steroids reduces the systemic reaction rate associated with RIT. METHODS: Patients with IFA hypersensitivity were randomized to placebo or twice-daily terfenadine 60 mg, ranitidine 150 mg, and prednisone 30 mg initiated 2 days before RIT in a double-blinded study. The 2-day RIT protocol consisted of hourly injections to achieve a final dose of 0.3 mL 1:100 wt/vol. Patients returned on day 8 to receive 2 hourly injections of 0.25 mL 1:100 wt/vol (total, 0.5 mL) and again on day 15 for a single injection of 0.5 mL 1:100 wt/vol. Efficacy of the protocol was determined on day 22, a pair of IFA sting challenges being performed 2 hours apart. RESULTS: Fifty-nine patients were enrolled into the study; a total of 58 patients (age range, 18 to 49 years) initiated the 2-day RIT. Only 3 patients (5.2%) experienced a mild systemic reaction during the protocol. Among those experiencing a systemic reaction with RIT, there was no statistical difference between the 2 premedication groups (3.6% active and 6.7% placebo; P =.87). Sting challenges were performed on 56 patients for a total of 112+ stings; only 1 mild systemic reaction occurred (efficacy, 98.2%). CONCLUSION: RIT with IFA WBE for IFA hypersensitivity is both safe and efficacious; the rate of mild systemic reactions is low. Premedication is not necessary, inasmuch as prophylactic pretreatment with antihistamines and steroids did not reduce the systemic reaction rate associated with RIT.