Abstracts S225
J ALLERGY CLIN IMMUNOL VOLUME 117, NUMBER 2
Local Anesthetic Allergy Characterized by Type IV Reactions in Patients Who Received Dental Anesthesia J. Melamed, W. N. Beaucher; Allergy and Asthma Specialists, Chelmsford, MA. RATIONALE: The recommended methodology of evaluating patients who have presented with reactions to local anesthetics consists of epicutaneous skin testing and serial subcutaneous challenge. However, the role of type IV reactions in this group has been poorly documented. METHODS: Routine testing/challenge to local anesthetic was performed, as well as patch testing and subcutaneous rechallenge with evaluation of both at 24 and 48 hours. RESULTS: Three patients presented with a history of localized edema following dental anesthesia. All had negative lidocaine and mepivacaine testing as well as negative lidocaine challenge on evaluation at 1 hour. The first patient, who had previously reactioned to EMLA, reacted to both lidocaine and mepivacaine patch testing and challenge, with delayed swelling at 24 and 48 hours following challenge. She subsequently tolerated the ester anesthetic chloroprocaine. Two other patients had strong histories of contact dermatitis. Patch testing and challenge with lidocaine was negative, but strong reactions were found to benzocaine on patch testing. CONCLUSIONS: Patients undergoing local anesthetic testing should be screened historically for features and risk factors associated with type IV reactions. This should be considered in patients who react to multiple amide anesthetics, who have delayed swelling, or who have a history of severe contact dermatitis. We confirm previous data showing that patients reacting to benzocaine can tolerate lidocaine and that lidocaine allergic individuals can tolerate ester anesthetics such as chloroprocaine.
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Successful Intravenous “Rush” Drug Desensitization to Meropenam Following Omalizumab Administration L. R. Hennessey1, R. Honicky2, S. Sudhanthar2, A. P. Dumpit3; 1Internal Medicine, and Pediatrics and Human Development, Michigan State
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University College of Human Medicine, East Lansing, MI, 2Pediatrics and Human Development, Michigan State University College of Human Medicine, East Lansing, MI, 3Emergency Medicine, Edward W. Sparrow Hospital, Lansing, MI. RATIONALE: Severe drug allergy may be encountered in cystic fibrosis and other diseases in which patients are exposed to multiple courses of antibiotics. “Rush” drug desensitization is often necessary in such cases, but can lead to severe and potentially life-threatening allergic reactions. Although only approved for the treatment of allergic asthma, the anti-IgE monoclonal antibody omalizumab should in theory reduce reactivity to any or all IgE-mediated allergic responses, including those to drugs. METHODS: We report our experience in the treatment of a fifteen year old girl with a history of allergy to multiple antibiotics including meropenam, who was hospitalized for a pulmonary exascerbation of cystic fibrosis. Sputum cultures revealed multiple strains of Burkholderia cepacia highly sensitive only to meropenam. Because the patient had poorly controlled allergic asthma with perennial triggers and an elevated IgE level, omalizumab therapy had been initiated six months earlier. Two previous attempts at meropenam desensitization had failed due to severe systemic reactions which occurred at a dose of only 10 mg. RESULTS: Following omalizumab administration, the patient was desensitized successfully to meropenam. She experienced only mild symptoms at a dose of 320 mg, and then received a total dose of 1000 mg without incident. Further evidence of IgE-mediated reactivity to meropenam was not noted during her subsequent course of treatment with the drug. CONCLUSIONS: This case suggests that omalizumab may be efficacious in the treatment of severe IgE-mediated drug allergy, and may reduce the risk associated with “rush” drug desensitization. Allergy Consultation and Skin Testing Benefits Significantly the Selection of the Antibiotic for Antibacterial Prophylaxis Preoperatively (ABPPO) in Patients Who Report Allergy to Penicillin (PRAP) E. Frigas, P. J. Markus, B. J. Narr, D. R. Danielson, P. A. Park, K. A. Bachman, P. A. Harris, M. M. O’Byrne, K. E. Kloos, G. W. Volcheck, H. Kita, D. R. Schroeder; Division of Allergic Diseases & Internal Medicine, Mayo Clinic College of Medicine, Rochester, MN. RATIONALE: Determine whether allergy consultation and testing in patients with PRAP impacts the selection of the antibiotic for ABPPO in elective surgery. METHODS: Demographic data, symptoms, and antibiotic use for ABPPO in patients with PRAP were collected from patient-completed standard preoperative questionnaires, anesthesia and surgical records. Of 4889 patients seen in the first 6 months of 2004 at the Preoperative Evaluation Clinic (POE), where patients with PRAP are evaluated and skin tested by an allergist before deciding which antibiotic to use for ABPPO, we studied 365 patients with PRAP. Of 416 patients seen at Other Preoperative Evaluation Settings (OPES) where patients with PRAP do not undergo allergy consultation, we studied 46 patients with PRAP. Logistic regression was used to assess whether allergy consultation was associated with choice of antibiotic for ABPPO, after adjusting for age, gender, and type of surgery. RESULTS: The frequency of PRAP was 7.5% at POE versus 11.1% at OPES (p=0.009). Compared to OPES, POE patients with PRAP were significantly younger (p=0.014) and more likely to have orthopedic procedures (p<0.001). The frequency of cephalosporin use for ABPPO was higher for PRAP patients seen at POE vs OPES (70% vs 39%, p<0.001 unadjusted; p=0.044 adjusted for age, gender and type of surgery) and the frequency of vancomycin use was lower for POE versus OPES (10% vs 28%, p<0.001 unadjusted, p=0.027 adjusted). There were no fatalities. CONCLUSIONS: In patients with PRAP, allergy consultation and testing significantly increased the utilization of cephalosporin and decreased the use of vancomycin for ABPPO in elective surgical procedures. Funding: Mayo Clinic College of Medicine
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MONDAY
The Value of Skin Testing in the Diagnosis of Betalactam Allergy M. J. Torres1, E. Martin1, C. Rondon1, C. Mayorga2, J. L. Rodriguez-Bada2, M. S. Fuentes1, I. Doña1, N. Blanca1, M. Blanca1; 1Allergy Service, Carlos Haya Hospital, Malaga, SPAIN, 2Research Laboratory, Carlos Haya Hospital, Malaga, SPAIN. RATIONALE: Allergy to betalactams is the most frequent cause of allergic drug reactions. Reliable in vivo methods, skin tests, and drug provocation tests are available to diagnose IgE mediated reactions. From the outset, the importance of skin testing was emphasized by using benzylpenicillin conjugated to poly-L-lysine (PPL) and benzylpenicillin plus benzylpenicilloic acid, the so-called minor determinants (MDM). Withdrawal from the market of PPL and MDM will severely hamper the diagnosis of patients allergic to betalactams. We evaluated the role of PPL and MDM in the diagnosis of immediate allergic reactions to betalactams. METHODS: In 2004 we studied the diagnostic value of skin testing using PPL, MDM, amoxicillin, and cephalosporins in 328 patients with a history of immediate allergic reactions to betalactams. RESULTS: Only 66 (20%) patients were confirmed as allergic. Of these, 55 were skin-test positive, 10 to PPL and/or MDM, 38 to amoxicillin and seven to cephalosporins. Eleven cases were skin-test negative, but seven of these had at least one in vitro test positive (CAP-FEIA-System® or BASOTEST®) and five required a drug provocation test. CONCLUSIONS: PPL/MDM were positive in the 15% of patients allergic to betalactams, showing that these determinants are still necessary for diagnosis. The absence of PPL/MDM and the lack of new determinants leave just two options: either selection of an alternative drug or desensitization, which requires trained personnel and adequate equipment with hospital facilities, and which will have to be undertaken any time the patient needs a betalactam. Funding: FIS and Fundacion Sociedad Española de Alergología e Inmunología Clínica
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