Misconceptions Surrounding Penicillin Allergy: Implications for Anesthesiologists.

Administration of preoperative antimicrobial prophylaxis, often with a cephalosporin, is the mainstay of surgical site infection prevention guidelines. Unfortunately, due to prevalent misconceptions, patients labeled as having a penicillin allergy often receive alternate and less-effective antibiotics, placing them at risk of a variety of adverse effects including increased morbidity and higher risk of surgical site infection. The perioperative physician should ascertain the nature of previous reactions to aid in determining the probability of the prevalence of a true allergy. Penicillin allergy testing may be performed but may not be feasible in the perioperative setting. Current evidence on the structural determinants of penicillin and cephalosporin allergies refutes the misconception of cross-reactivity between penicillins and cefazolin, and there is no clear evidence of an increased risk of anaphylaxis in cefazolin-naive, penicillin-allergic patients. A clinical practice algorithm for the perioperative evaluation and management of patients reporting a history of penicillin allergy is presented, concluding that cephalosporins can be safely administered to a majority of such patients.

Evaluation of immediate allergic reactions to cephalosporins in non-penicillin-allergic patients.

BACKGROUND: Cephalosporins can induce severe or life-threatening IgE-mediated reactions in some individuals. In this study, we wish to describe a group of non-penicillin-allergic patients who were evaluated for immediate allergic reactions to cephalosporins. METHODS: The patients were assessed by skin tests with the culprit cephalosporin as well as with other cephalosporins and penicillins. If indicated, oral challenge testing was performed. RESULTS: Six patients were assessed. A total of 42 skin tests and 20 oral challenges were performed. In 4 patients, skin tests included the causative drug; in 2 patients, the diagnosis of a cephalosporin allergy was made by skin test; in 4 patients, the diagnosis of a cephalosporin hypersensitivity was made by oral challenge. In 96.9% of the oral challenges, which were done using medications with no structural side chain similarities to the culprit drug, no adverse reaction occurred. CONCLUSION: A positive skin test to cephalosporin implies the presence of drug-specific IgE antibodies. Cephalosporins without side chain similarities are suggested to patients with cephalosporin reactions and no beta-lactam reactivity.

Management options for patients with aspirin and nonsteroidal antiinflammatory drug sensitivity.

OBJECTIVE: To evaluate and provide management strategies for patients with aspirin or nonselective nonsteroidal antiinflammatory drug (NSAID) sensitivity. DATA SOURCES: Literature retrieval was accessed through MEDLINE (1966-March 2007) using the terms acetaminophen, aspirin, antiinflammatory agents nonsteroidal, urticaria, angioedema, asthma, leukotriene antagonists, desensitization, and tacrolimus. Article references retrieved were hand-searched for other relevant articles. STUDY SELECTION AND DATA EXTRACTION: All studies published in English were evaluated. Studies, review articles, and commentaries on aspirin-induced asthma and aspirin- or NSAID-induced urticaria/angioedema were included in the review. DATA SYNTHESIS: Aspirin sensitivity is most often manifested as respiratory reactions (eg, bronchospasm, profuse rhinorrhea, conjunctival injection) or urticaria/angioedema. The primary mechanism is believed to be inhibition of the cyclooxygenase 1 (COX-1) enzyme; as such, patients with aspirin sensitivity often display cross-reactions to nonselective NSAIDs that inhibit the COX-1 enzyme. Management strategies include avoidance of aspirin and cross-reacting nonselective NSAIDs. However, desensitization to aspirin is a viable option for patients with aspirin-induced respiratory reactions, especially for those who require aspirin for thromboembolic prophylaxis. Aspirin desensitization is maintained indefinitely with a daily aspirin dose. There is limited evidence of the use of leukotriene modifiers in preventing aspirin-induced asthma. COX-2 selective NSAIDs, especially in patients with aspirin-induced asthma, have not been found to cross-react. However, approximately 4% of patients with a history of aspirin-induced skin reactions may experience a cutaneous reaction following a challenge to a COX-2 selective NSAID. Since acetaminophen is a weak inhibitor of the COX-1 enzyme, patients with aspirin-induced asthma should not take more than 1000 mg of acetaminophen in a single dose. CONCLUSIONS: Management of patients with aspirin/NSAID sensitivity includes avoidance of aspirin/nonselective NSAIDs, use of COX-2 selective NSAIDs, acetaminophen in doses less than 1000 mg, and desensitization. The role of leukotriene modifiers requires further study before they can be recommended for patients.

Allergic reaction to fluorescein dye: successful one-day desensitization.

CASE REPORT: An 86-year-old woman developed IgE-mediated generalized urticaria after a second fluorescein injection. A one-day desensitization protocol was successfully administered that permitted continuation of angiography for deteriorating vision. COMMENTS: We review the literature on adverse events associated with administration of fluorescein and suggest guidelines for testing and desensitization.

Povidone-iodine-induced burn: case report and review of the literature.

Burns are a rare but potentially serious complication of povidone-iodine use. This rare adverse drug reaction developed in a 38-year-old woman who underwent laparoscopic right ovarian cystectomy and endometrial ablation as a day procedure involving application of the topical antiseptic 10% povidone-iodine solution. Two days later, the patient was admitted to the hospital with burning, pain, itching, marked redness, and blistering extending from her midback to buttocks. A stain on her back also was evident. Partial-thickness chemical burn was diagnosed. Review of the literature yielded 13 other cases of povidone-iodine-induced burn. This underrecognized adverse effect of povidone-iodine application typically occurs when the povidone-iodine has not been allowed to dry or has been trapped under the body of a patient in a pooled dependent position. The burn is usually seen immediately after the procedure or on the next day, and typically heals with minimum scarring within 3-4 weeks with conservative treatment. The commonly postulated mechanism is a chemical burn due to irritation coupled with maceration, friction, and pressure. Given the widespread use of povidone-iodine and the potential for development of infection after a burn, clinicians need to be aware of this possible povidone-iodine-associated adverse drug reaction, and of preventive measures.

Clindamycin skin testing has limited diagnostic potential.

We examined the role of clindamycin prick and intradermal skin testing in a tertiary care clinic population. Experience with diagnostic modalities such as prick and intradermal testing has been limited with clindamycin. A retrospective chart review was conducted for patients with immunologic reactions temporally associated with clindamycin who were referred to the Drug Safety Clinic (Toronto, Ontario). A total of 31 patients were identified who had undergone prick and intradermal skin testing. All 31 negative immediate prick and intradermal tests were followed by a 150 mg oral dose of clindamycin. 10/31 (32%) subjects had significant reactions to the oral clindamycin provocation. 2 patients reported delayed reactions at the clindamycin intradermal test sites. Our experience suggests that prick and intradermal skin testing is not adequate in identifying patients with previous allergic reactions associated with clindamycin. Oral provocation tests can be used in patients with histories of clindamycin adverse reactions; however, it should be offered on a risk-benefit basis.