HOUSTON – What is the most reliable test for determining whether a patient has outgrown a penicillin allergy? Allergists’ preferences vary widely, judging from findings of an e-mail survey presented at the annual meeting of the American Academy of Allergy, Asthma, and Immunology.
The investigators polled 652 AAAAI-member allergists to determine how practitioners were evaluating and either labeling or unlabeling patients with suspected penicillin allergy.
Deepak Chitnis/Frontline Medical News
Dr. Kali Gerace
“The majority of patients outgrow penicillin allergies within 5 years – over 80% – so the problem becomes what’s the best way of removing that label from their charts,” explained Dr. Kali Gerace of Vanderbilt University, Nashville, Tenn., in an interview. “Among allergy providers, the practice is variable partly [because] of availability of the reagents; for example, Pre-Pen is on the market for anyone who wants to get it, but MDM (minor determinant mixture) is not commercially available, and therefore you can only test to it if your institution makes it.”
AAAAI allergists reported that they most often used Pre-Pen, penicillin G, and MDM as their preferred form of skin-prick or intradermal testing. Of these, penicillin G was used more than MDM by a ratio of 75.2% to 38.3%. On the other hand, academic practices were more likely to use MDM, with 44% reporting their preference for MDM while only 36% of all other practitioners responded similarly (P = .09). Allergists in practice for less than 10 years were more likely to prefer oral challenge testing to assess penicillin allergy, with 93% responding as such, compared with 85% of the rest of allergists surveyed (P = .01).
Of practices performing both skin-prick testing and oral challenge, 163 (35.7%) said they advised patients to take all penicillins and cephalosporins; 120 (26.3%) advised patients to only take the drugs that they safely passed the oral challenge with. Seventy-four (16.2%) respondents said they advised patients to take a beta-lactam only if the benefit outweighed the risk, 40 (8.8%) said they advise taking only penicillins or cephalosporins with negative testing, 15 (3.3%) said they do not offer any recommendations and prefer leaving it up to patients and primary care providers to determine the best course of action, and 45 (9.8%) reported following “other” protocols.
Practices that reported using only skin testing did not have significantly different rates from those offering no recommendations and those reporting “other” protocols: 3 (4.9%) and 5 (8.2%), respectively. However, 13 (21.3%) advised patients to take all penicillins and cephalosporins, while 20 (32.8%) advised taking only those medications for which the patient tested negative, 4 (6.6%) recommended taking antibiotics to which the patients showed no allergy on oral challenge, and 18 (29.5%) recommended beta-lactams in certain situations.
Overall, 72% of those surveyed said that they preferred using skin-prick testing and oral challenge to determine penicillin allergy, compared with 18% who preferred skin-prick testing alone. Oral challenge alone was reported by 4% of those surveyed, and 6% reported “no testing available.” Private practices accounted for 62.3% of those surveyed, with academic practices making up 26.2% of the population, managed care comprising 5.2%, and combination practices the remaining 3.7%.
“As allergy providers, we can achieve standardization by revising our practice parameters and making them more specific to the best method for testing,” said Dr. Gerace. “We need to find the most cost-effective way of dealing with [these] patients and finding a way to standardize the advice we give them as providers.”
Dr. Gerace did not report any relevant financial disclosures.