Clinical Communications A survey of physician practice and knowledge of drug allergy at a university medical center Jacquelyn M. Sturm, MD, and James Temprano, MD, MHA Clinical Implication
Physicians treat patients with drug allergies on a regular basis and may benefit from more education on drug allergy during medical school and residency training.
TO THE EDITOR: Adverse drug reactions affect 10% to 20% of hospitalized patients and more than 7% of the general population.1 It has been estimated that adverse drug reactions may constitute the sixth leading cause of death in the United States after heart disease, cancer, stroke, pulmonary disease, and accidents.2 Physicians regularly face the question of whether a patient-reported allergy is accurate and how the drug allergy (DA) will affect patient care. Patients are commonly labeled as being drug allergic due to vague symptoms that do not correspond to a true allergic reaction. Patients with reported allergy to penicillin may be treated with more expensive nonpenicillin class antibiotics.3 Trends in antibiotic prescription rates are showing an increase in the use of broad-spectrum antibiotics, namely azithromycin and quinolones.4 Ultimately, the physician must make an educated decision about the validity of reported DA. Allergy to penicillin is regularly found in medical charts. Up to 10% of all patients report a penicillin allergy.5 Patients may attribute nonallergic rashes during viral illness, headaches, or gastrointestinal symptoms to a penicillin allergy.6 Most patients who report a penicillin allergy can tolerate penicillin, but often physicians will prescribe a different class of antibiotics. It also has been reported that penicillin allergy and labels that state penicillin allergy on medical files are ignored in one-third of patients who receive antibiotics.7 How a physician interprets a reported penicillin allergy depends on his or her knowledge of DA and affects future patient care. The objective of the study was to determine current physician knowledge and practice patterns regarding DA at our university medical center. Previous studies looked at physician knowledge and approach toward penicillin allergy but not DA outside of penicillin.8-11 In our study, we hoped to further explore DA and physician practice throughout various medical specialties and training levels. The study was approved by the Saint Louis University Institutional Review Board. We created a survey through SurveyMonkey (Palo Alto, CA) that looked at physician management of patients with DA, knowledge of DA, and knowledge of clinical indications for skin testing (ST) and desensitization. The survey contained 12 questions (Table I), but questions 8 and 9 were scored as 11 different questions each, which led to 32 total questions, 7 of which were training and/or practice questions, and 25 of which were knowledge questions. Initial questions collected demographic information, including
level of training and medical specialty. Later questions addressed DA practice patterns and DA knowledge. E-mails of the survey were sent to 986 physicians in all departments at Saint Louis University, including attending physicians, residents, and interns. The responses to the survey were directly entered into the SurveyMonkey online database. Descriptive statistics and unpaired t tests for comparisons among groups were performed by using SAS 9.1 (SAS Institute, Cary, NC). A P < .05 was used for evaluation of statistical significance. A total of 242 of the 986 surveys were completed by using SurveyMonkey, for a response rate of 24.5%. When looking at the training level, 45.04% of responders identified themselves as attending physicians. The response rate was evenly distributed throughout specialties, with the largest response from internal medicine, at 17.36% (Figure 1). We determined the level of experience by years in practice since medical school, and the mean for all responders was 11.64 years in practice. The average percentage of patients seen by respondents who reported any DA was 31.84%. Respondents thought that only 30.64% of patients who reported DA would react if given the suspected drug; however, only 15.05% stated that they would give the drug in this situation. Of the respondents, 48.76% reported previously performing or ordering a consult for drug desensitization. Of the 25 knowledge questions about DA, the average score for the cohort was 16.65 of 25 (66.6%). The knowledge questions also included a list of 11 drugs paired with clinical manifestations and asked respondents to pick the correct pairings as indications for ST or desensitization. Urticaria with penicillin was the most frequent correct answer as a clinical indication for ST (83.06%) and desensitization (69.0%); however, only 43.0% and 47.9% of respondents cited anaphylaxis with piperacillin as an indication for ST and desensitization, respectively. When looking at the pairings for ST and desensitization in relationship to aspirin, respondents generally knew that ST is not performed in the evaluation of aspirin allergy. In comparison, the pairings of aspirin to anaphylaxis, angioedema, and aspirin exacerbated respiratory disease (AERD) as an indication for desensitization were less frequently answered correctly. For anaphylaxis, angioedema, and AERD, only 31.40%, 19.83%, and 14.87% of respondents, respectively, chose desensitization as a treatment option. The final question addressed the correct test for confirmation of anaphylaxis, and 13.64% of respondents chose serum total tryptase as the correct answer. Although no significant differences were found regarding DA knowledge between attending physicians and residents, or between primary care physicians and specialists, physicians with any internal medicine training did score significantly higher than those without such training (average correct, 17.36 [69.44%] vs 16.31 [65%]; P < .01). In our study, we surveyed current physician practice habits in patients with a DA and physician knowledge of DA. To our knowledge, this is the first study that looked at nonallergyetrained physician knowledge of desensitization for various medications. Previous DA studies also showed a need for further physician education to address DA.8 Previous DA surveys looked at the prescribing habits of physicians in relation to penicillin 1
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CLINICAL COMMUNICATIONS
J ALLERGY CLIN IMMUNOL PRACT MONTH 2014
TABLE I. Drug allergy questionnaire Questions
Responses (N [ 242)
Possible selections
1. What is your level of training? 2. What is your medical specialty? 3. What year did you graduate from medical school? 4. Approximately what percentage of patients seen in your practice report any drug allergy? 5. Of patients reporting a reaction to a particular drug, what percentage do you believe would have a reaction if given the medication? 6. If one of your patients reports a drug allergy and you do not believe that the patient is truly allergic to that medication, what percentage of the time do you still give the medication? 7. How many times have you either requested (through a consult) or performed a drug challenge or desensitization procedure?
45.0% attending physicians See Figure 1 Average 11.6 y in practice 31.8% 30.6%
15.1%
0 times 1-4 times 5 times 6-10 times >10 times 8. ST can be used for evaluation in which of the following drug reaction pairs? Check all that apply. Headache with montelukast Nausea and/or vomiting with morphine Macular, erythematous rash with trimethoprimsulfamethoxazole 9. A DS procedure can be used for patient treatment in which of the following drug reaction pairs? Check all that apply. Urticaria with penicillin Angioedema with aspirin Angioedema with lisinopril Anaphylaxis with aspirin Shortness of breath, wheezing and nasal polyps with aspirin Anaphylaxis with piperacillin Steven-Johnson syndrome with penicillin Toxic epidermal necrolysis with phenytoin
51.2% 39.2% 2.5% 3.3% 3.7% % ST correct answers
% DS correct answers
94 94.2 51.7
87.2 91.3
% ST correct answers
% DS correct answers
83 78.9 85.1 72.3 88
69 19.8 88 31.4 14.8
43 83 88
47.9 88 94.6
10. What percentage of patients with a history of penicillin allergy can tolerate penicillin? 0%-10% 11%-25% 26%-50% 51%-75% >75%
8.7% 30.2% 29.3% 16.9% 14.9%
0%-15% 16%-25% 26%-50% 51%-75% >75%
60.3% 23.6% 12.4% 2.1% 1.7%
11. What percentage of patients with a history of penicillin allergy will also be allergic to cephalosporins?
(continued)
CLINICAL COMMUNICATIONS
J ALLERGY CLIN IMMUNOL PRACT VOLUME -, NUMBER -
3
TABLE I. (Continued) Questions
Possible selections
Responses (N [ 242)
12. If an anaphylactic reaction to a drug is suspected, then which of the following tests may be ordered for confirmation of anaphylaxis? C1q binding assay Plasma histamine Serum specific IgE level Serum total tryptase I don’t know
8.7% 6.2% 24.8% 13.6% 46.7%
DS, Desensitization.
FIGURE 1. Medical specialty of survey respondents.
allergy.8-11 The surveys revealed wide variation in antibiotic treatment, depending on the history of the penicillin reaction. In a survey performed by Puchner and Zacharisen,8 more than 30% of pediatricians and internists surveyed were unaware of the existence of standardized penicillin STs. A ST is an appropriate option for evaluation of a penicillin allergy and may be an underused resource for drug evaluation. Reaction history is a poor predictor of patients who will have a positive penicillin ST response, and any patient with a history of a possible IgE-mediated reaction to penicillin is a candidate for ST.12 In our study, 83.06% of respondents correctly paired urticaria with penicillin as an indication for ST, which revealed a higher level of knowledge than previously reported. Although ST for penicillin was well known, piperacillin and anaphylaxis was correctly chosen as an indication for ST only 43.0% of the time. In our survey, the physicians had a higher level of knowledge of indications for ST and desensitization in penicillin allergy compared with aspirin allergy. To determine if our hospital allergy consult service played a role in physician knowledge of ST and desensitization, we reviewed consults performed at Saint
Louis University Hospital for DA. In the past 2 years, 69 consults were performed for DA in an inpatient hospital setting. Fifteen consults related specifically to penicillin allergy and 10 were related to aspirin allergy. Nine of the 10 aspirin allergy consults were ordered by the cardiology service, whereas the penicillin allergy consults were placed by various departments, including internal medicine, neurology, and surgical services. Clearly, the low number of respondents (31.4%) correctly choosing anaphylaxis with aspirin as an indication for desensitization compared with 69% for penicillin and urticaria may be related to the scope of their medical practice. A history of penicillin allergy may lead to an increase in health care costs. Fewer than 5% of patients with a history of penicillin allergy are confirmed to be allergic, based on recent studies.13,14 A study performed by MacLaughlin et al15 looked at the cost of b-lactam allergies. The study evaluated patients treated for upper respiratory tract infection, otitis media, sinusitis, and urinary tract infection. The mean antibiotic cost for patients with a history of b-lactam allergy was $26.81 compared with $16.28 for patients without a history of allergy to a b-lactam. In comparison
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with outpatient costs, Sade et al16 looked at the antibiotic costs for hospitalized patients with penicillin allergy. The mean antibiotic cost for patients with penicillin allergy was 63% higher than the cost for the controls. On discharge, there was 38% higher cost for the recommended antimicrobial treatment regimen compared with controls. Macy et al3 showed penicillin ST to be associated with a decline in the number of antibiotic courses by 28% and total cost of antibiotics by 32% the year after ST. It was thought that the decrease in antibiotic use was secondary to resolution of the condition or due to allergist evaluation and appropriate diagnosis. Clearly, the ability to stratify patients with penicillin allergy may influence antibiotic costs and overall health care costs. Surprisingly, the level of training did not affect DA knowledge in our study, but physicians with any internal medicine training performed significantly better. This is in contrast with previous studies that demonstrated better performance by pediatric residents on a survey of penicillin allergy.8 Although previous studies focused on penicillin allergy, our survey looked at evaluation and management of allergy to various antibiotics and aspirin in addition to penicillin, which may be more relevant to an adult population compared with pediatric populations. After the survey was completed, a few flaws were discovered in the survey questions. Question 9, specifically, which matches indications for ST and desensitization may not have clear-cut answers. Macular, erythematous rash with trimethoprimsulfamethoxazole may be an indication for desensitization if referring to patients with HIV. Also, the questions related to aspirin desensitization are controversial. For example, angioedema could coexist with AERD and be considered an indication for aspirin desensitization but not an indication if related to chronic urticaria exacerbated by aspirin. Also, anaphylaxis with aspirin has never been convincingly described in the literature. Ultimately, the questions were included in the results, despite their limitations. In conclusion, DA is a common issue that affects patient care on a regular basis in both outpatient and inpatient settings. An important next step would be to perform an intervention study to attempt to improve physician knowledge of drug allergy and behavior that leads to improved outcomes. Division of Allergy and Immunology, Saint Louis University, St. Louis, Mo
J ALLERGY CLIN IMMUNOL PRACT MONTH 2014
No funding was received for this work. Conflicts of interest: J. Temprano has received research support from Merck and Dyax; has received lecture fees from Baxter. J. M. Sturm declares that she has no relevant conflicts of interest. Received for publication November 27, 2013; revised February 2, 2014; accepted for publication February 11, 2014. Corresponding author: Jacquelyn M. Sturm, MD, Allergy, Asthma & Immunology Center, 325 Tamarack Lane, Shiloh, IL 62269. E-mail: [email protected]. 2213-2198/$36.00 Ó 2014 American Academy of Allergy, Asthma & Immunology http://dx.doi.org/10.1016/j.jaip.2014.02.004
REFERENCES 1. Gomes ER, Demoly P. Epidemiology of hypersensitivity drug reactions. Curr Opin Allergy Clin Immunol 2005;5:309-16. 2. Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug reactions in hospitalized patients: a meta-analysis of prospective studies. JAMA 1998;279: 1200-5. 3. Macy E. Elective penicillin skin testing and amoxicillin challenge: effect on outpatient antibiotic use, cost, and clinical outcomes. J Allergy Clin Immunol 1998;102:281-5. 4. Grijalva CG. Antibiotic prescription rates for acute respiratory tract infections in US ambulatory settings. JAMA 2009;302:758-66. 5. Solensky R. Hypersensitivity reactions to beta-lactam antibiotics. Clin Rev Allergy Immunol 2003;24:201-19. 6. Yates AB. Management of patients with a history of allergy to beta-lactam antibiotics. Am J Med 2008;121:572-6. 7. Borch JE, Andersen KE, Bindslev-Jensen C. The prevalence of suspected and challenge-verified penicillin allergy in a university hospital population. Basic Clin Pharmacol Toxicol 2006;98:357-62. 8. Puchner TC Jr, Zacharisen MC. A survey of antibiotic prescribing and knowledge of penicillin allergy. Ann Allergy Asthma Immunol 2002;88: 24-9. 9. Solensky R, Earl HS, Gruchalla RS. Clinical approach to penicillin-allergic patients: a survey. Ann Allergy Asthma Immunol 2000;84:329-33. 10. Wickern GM, Nish WA, Bitner AS, Freeman TM. Allergy to beta-lactams: a survey of current practices. J Allergy Clin Immunol 1994;94:725-31. 11. Prematta T, Shah S, Ishmael FT. Physician approaches to beta-lactam use in patients with penicillin hypersensitivity. Allergy Asthma Proc 2012;33:145-51. 12. Khan DA, Solensky R. Drug allergy. J Allergy Clin Immunol 2010;125: S126-37. 13. Jost BC, Wedner HJ, Bloomberg GR. Elective penicillin skin testing in a pediatric outpatient setting. Ann Allergy Asthma Immunol 2006;97:807-12. 14. Macy E, Shatz M, Lin C, Poon KY. The falling rate of positive penicillin skin tests from 1995 to 2007. Perm J 2009;13:12-8. 15. MacLaughlin EJ, Saseen JJ, Malone DC. Costs of beta-lactam allergies: selection and costs of antibiotics for patients with a reported beta-lactam allergy. Arch Fam Med 2000;9:722-6. 16. Sade K, Holtzer I, Levo Y, Kivity S. The economic burden of antibiotic treatment of penicillin-allergic patients in internal medicine wards of a general tertiary care hospital. Clin Exp Allergy 2003;33:501-6.
Physicians treat patients with drug allergies on a regular basis and may benefit from more education on drug allergy during medical school and residency training.
TO THE EDITOR: Adverse drug reactions affect 10% to 20% of hospitalized patients and more than 7% of the general population.1 It has been estimated that adverse drug reactions may constitute the sixth leading cause of death in the United States after heart disease, cancer, stroke, pulmonary disease, and accidents.2 Physicians regularly face the question of whether a patient-reported allergy is accurate and how the drug allergy (DA) will affect patient care. Patients are commonly labeled as being drug allergic due to vague symptoms that do not correspond to a true allergic reaction. Patients with reported allergy to penicillin may be treated with more expensive nonpenicillin class antibiotics.3 Trends in antibiotic prescription rates are showing an increase in the use of broad-spectrum antibiotics, namely azithromycin and quinolones.4 Ultimately, the physician must make an educated decision about the validity of reported DA. Allergy to penicillin is regularly found in medical charts. Up to 10% of all patients report a penicillin allergy.5 Patients may attribute nonallergic rashes during viral illness, headaches, or gastrointestinal symptoms to a penicillin allergy.6 Most patients who report a penicillin allergy can tolerate penicillin, but often physicians will prescribe a different class of antibiotics. It also has been reported that penicillin allergy and labels that state penicillin allergy on medical files are ignored in one-third of patients who receive antibiotics.7 How a physician interprets a reported penicillin allergy depends on his or her knowledge of DA and affects future patient care. The objective of the study was to determine current physician knowledge and practice patterns regarding DA at our university medical center. Previous studies looked at physician knowledge and approach toward penicillin allergy but not DA outside of penicillin.8-11 In our study, we hoped to further explore DA and physician practice throughout various medical specialties and training levels. The study was approved by the Saint Louis University Institutional Review Board. We created a survey through SurveyMonkey (Palo Alto, CA) that looked at physician management of patients with DA, knowledge of DA, and knowledge of clinical indications for skin testing (ST) and desensitization. The survey contained 12 questions (Table I), but questions 8 and 9 were scored as 11 different questions each, which led to 32 total questions, 7 of which were training and/or practice questions, and 25 of which were knowledge questions. Initial questions collected demographic information, including
level of training and medical specialty. Later questions addressed DA practice patterns and DA knowledge. E-mails of the survey were sent to 986 physicians in all departments at Saint Louis University, including attending physicians, residents, and interns. The responses to the survey were directly entered into the SurveyMonkey online database. Descriptive statistics and unpaired t tests for comparisons among groups were performed by using SAS 9.1 (SAS Institute, Cary, NC). A P < .05 was used for evaluation of statistical significance. A total of 242 of the 986 surveys were completed by using SurveyMonkey, for a response rate of 24.5%. When looking at the training level, 45.04% of responders identified themselves as attending physicians. The response rate was evenly distributed throughout specialties, with the largest response from internal medicine, at 17.36% (Figure 1). We determined the level of experience by years in practice since medical school, and the mean for all responders was 11.64 years in practice. The average percentage of patients seen by respondents who reported any DA was 31.84%. Respondents thought that only 30.64% of patients who reported DA would react if given the suspected drug; however, only 15.05% stated that they would give the drug in this situation. Of the respondents, 48.76% reported previously performing or ordering a consult for drug desensitization. Of the 25 knowledge questions about DA, the average score for the cohort was 16.65 of 25 (66.6%). The knowledge questions also included a list of 11 drugs paired with clinical manifestations and asked respondents to pick the correct pairings as indications for ST or desensitization. Urticaria with penicillin was the most frequent correct answer as a clinical indication for ST (83.06%) and desensitization (69.0%); however, only 43.0% and 47.9% of respondents cited anaphylaxis with piperacillin as an indication for ST and desensitization, respectively. When looking at the pairings for ST and desensitization in relationship to aspirin, respondents generally knew that ST is not performed in the evaluation of aspirin allergy. In comparison, the pairings of aspirin to anaphylaxis, angioedema, and aspirin exacerbated respiratory disease (AERD) as an indication for desensitization were less frequently answered correctly. For anaphylaxis, angioedema, and AERD, only 31.40%, 19.83%, and 14.87% of respondents, respectively, chose desensitization as a treatment option. The final question addressed the correct test for confirmation of anaphylaxis, and 13.64% of respondents chose serum total tryptase as the correct answer. Although no significant differences were found regarding DA knowledge between attending physicians and residents, or between primary care physicians and specialists, physicians with any internal medicine training did score significantly higher than those without such training (average correct, 17.36 [69.44%] vs 16.31 [65%]; P < .01). In our study, we surveyed current physician practice habits in patients with a DA and physician knowledge of DA. To our knowledge, this is the first study that looked at nonallergyetrained physician knowledge of desensitization for various medications. Previous DA studies also showed a need for further physician education to address DA.8 Previous DA surveys looked at the prescribing habits of physicians in relation to penicillin 1
2
CLINICAL COMMUNICATIONS
J ALLERGY CLIN IMMUNOL PRACT MONTH 2014
TABLE I. Drug allergy questionnaire Questions
Responses (N [ 242)
Possible selections
1. What is your level of training? 2. What is your medical specialty? 3. What year did you graduate from medical school? 4. Approximately what percentage of patients seen in your practice report any drug allergy? 5. Of patients reporting a reaction to a particular drug, what percentage do you believe would have a reaction if given the medication? 6. If one of your patients reports a drug allergy and you do not believe that the patient is truly allergic to that medication, what percentage of the time do you still give the medication? 7. How many times have you either requested (through a consult) or performed a drug challenge or desensitization procedure?
45.0% attending physicians See Figure 1 Average 11.6 y in practice 31.8% 30.6%
15.1%
0 times 1-4 times 5 times 6-10 times >10 times 8. ST can be used for evaluation in which of the following drug reaction pairs? Check all that apply. Headache with montelukast Nausea and/or vomiting with morphine Macular, erythematous rash with trimethoprimsulfamethoxazole 9. A DS procedure can be used for patient treatment in which of the following drug reaction pairs? Check all that apply. Urticaria with penicillin Angioedema with aspirin Angioedema with lisinopril Anaphylaxis with aspirin Shortness of breath, wheezing and nasal polyps with aspirin Anaphylaxis with piperacillin Steven-Johnson syndrome with penicillin Toxic epidermal necrolysis with phenytoin
51.2% 39.2% 2.5% 3.3% 3.7% % ST correct answers
% DS correct answers
94 94.2 51.7
87.2 91.3
% ST correct answers
% DS correct answers
83 78.9 85.1 72.3 88
69 19.8 88 31.4 14.8
43 83 88
47.9 88 94.6
10. What percentage of patients with a history of penicillin allergy can tolerate penicillin? 0%-10% 11%-25% 26%-50% 51%-75% >75%
8.7% 30.2% 29.3% 16.9% 14.9%
0%-15% 16%-25% 26%-50% 51%-75% >75%
60.3% 23.6% 12.4% 2.1% 1.7%
11. What percentage of patients with a history of penicillin allergy will also be allergic to cephalosporins?
(continued)
CLINICAL COMMUNICATIONS
J ALLERGY CLIN IMMUNOL PRACT VOLUME -, NUMBER -
3
TABLE I. (Continued) Questions
Possible selections
Responses (N [ 242)
12. If an anaphylactic reaction to a drug is suspected, then which of the following tests may be ordered for confirmation of anaphylaxis? C1q binding assay Plasma histamine Serum specific IgE level Serum total tryptase I don’t know
8.7% 6.2% 24.8% 13.6% 46.7%
DS, Desensitization.
FIGURE 1. Medical specialty of survey respondents.
allergy.8-11 The surveys revealed wide variation in antibiotic treatment, depending on the history of the penicillin reaction. In a survey performed by Puchner and Zacharisen,8 more than 30% of pediatricians and internists surveyed were unaware of the existence of standardized penicillin STs. A ST is an appropriate option for evaluation of a penicillin allergy and may be an underused resource for drug evaluation. Reaction history is a poor predictor of patients who will have a positive penicillin ST response, and any patient with a history of a possible IgE-mediated reaction to penicillin is a candidate for ST.12 In our study, 83.06% of respondents correctly paired urticaria with penicillin as an indication for ST, which revealed a higher level of knowledge than previously reported. Although ST for penicillin was well known, piperacillin and anaphylaxis was correctly chosen as an indication for ST only 43.0% of the time. In our survey, the physicians had a higher level of knowledge of indications for ST and desensitization in penicillin allergy compared with aspirin allergy. To determine if our hospital allergy consult service played a role in physician knowledge of ST and desensitization, we reviewed consults performed at Saint
Louis University Hospital for DA. In the past 2 years, 69 consults were performed for DA in an inpatient hospital setting. Fifteen consults related specifically to penicillin allergy and 10 were related to aspirin allergy. Nine of the 10 aspirin allergy consults were ordered by the cardiology service, whereas the penicillin allergy consults were placed by various departments, including internal medicine, neurology, and surgical services. Clearly, the low number of respondents (31.4%) correctly choosing anaphylaxis with aspirin as an indication for desensitization compared with 69% for penicillin and urticaria may be related to the scope of their medical practice. A history of penicillin allergy may lead to an increase in health care costs. Fewer than 5% of patients with a history of penicillin allergy are confirmed to be allergic, based on recent studies.13,14 A study performed by MacLaughlin et al15 looked at the cost of b-lactam allergies. The study evaluated patients treated for upper respiratory tract infection, otitis media, sinusitis, and urinary tract infection. The mean antibiotic cost for patients with a history of b-lactam allergy was $26.81 compared with $16.28 for patients without a history of allergy to a b-lactam. In comparison
4
CLINICAL COMMUNICATIONS
with outpatient costs, Sade et al16 looked at the antibiotic costs for hospitalized patients with penicillin allergy. The mean antibiotic cost for patients with penicillin allergy was 63% higher than the cost for the controls. On discharge, there was 38% higher cost for the recommended antimicrobial treatment regimen compared with controls. Macy et al3 showed penicillin ST to be associated with a decline in the number of antibiotic courses by 28% and total cost of antibiotics by 32% the year after ST. It was thought that the decrease in antibiotic use was secondary to resolution of the condition or due to allergist evaluation and appropriate diagnosis. Clearly, the ability to stratify patients with penicillin allergy may influence antibiotic costs and overall health care costs. Surprisingly, the level of training did not affect DA knowledge in our study, but physicians with any internal medicine training performed significantly better. This is in contrast with previous studies that demonstrated better performance by pediatric residents on a survey of penicillin allergy.8 Although previous studies focused on penicillin allergy, our survey looked at evaluation and management of allergy to various antibiotics and aspirin in addition to penicillin, which may be more relevant to an adult population compared with pediatric populations. After the survey was completed, a few flaws were discovered in the survey questions. Question 9, specifically, which matches indications for ST and desensitization may not have clear-cut answers. Macular, erythematous rash with trimethoprimsulfamethoxazole may be an indication for desensitization if referring to patients with HIV. Also, the questions related to aspirin desensitization are controversial. For example, angioedema could coexist with AERD and be considered an indication for aspirin desensitization but not an indication if related to chronic urticaria exacerbated by aspirin. Also, anaphylaxis with aspirin has never been convincingly described in the literature. Ultimately, the questions were included in the results, despite their limitations. In conclusion, DA is a common issue that affects patient care on a regular basis in both outpatient and inpatient settings. An important next step would be to perform an intervention study to attempt to improve physician knowledge of drug allergy and behavior that leads to improved outcomes. Division of Allergy and Immunology, Saint Louis University, St. Louis, Mo
J ALLERGY CLIN IMMUNOL PRACT MONTH 2014
No funding was received for this work. Conflicts of interest: J. Temprano has received research support from Merck and Dyax; has received lecture fees from Baxter. J. M. Sturm declares that she has no relevant conflicts of interest. Received for publication November 27, 2013; revised February 2, 2014; accepted for publication February 11, 2014. Corresponding author: Jacquelyn M. Sturm, MD, Allergy, Asthma & Immunology Center, 325 Tamarack Lane, Shiloh, IL 62269. E-mail: [email protected]. 2213-2198/$36.00 Ó 2014 American Academy of Allergy, Asthma & Immunology http://dx.doi.org/10.1016/j.jaip.2014.02.004
REFERENCES 1. Gomes ER, Demoly P. Epidemiology of hypersensitivity drug reactions. Curr Opin Allergy Clin Immunol 2005;5:309-16. 2. Lazarou J, Pomeranz BH, Corey PN. Incidence of adverse drug reactions in hospitalized patients: a meta-analysis of prospective studies. JAMA 1998;279: 1200-5. 3. Macy E. Elective penicillin skin testing and amoxicillin challenge: effect on outpatient antibiotic use, cost, and clinical outcomes. J Allergy Clin Immunol 1998;102:281-5. 4. Grijalva CG. Antibiotic prescription rates for acute respiratory tract infections in US ambulatory settings. JAMA 2009;302:758-66. 5. Solensky R. Hypersensitivity reactions to beta-lactam antibiotics. Clin Rev Allergy Immunol 2003;24:201-19. 6. Yates AB. Management of patients with a history of allergy to beta-lactam antibiotics. Am J Med 2008;121:572-6. 7. Borch JE, Andersen KE, Bindslev-Jensen C. The prevalence of suspected and challenge-verified penicillin allergy in a university hospital population. Basic Clin Pharmacol Toxicol 2006;98:357-62. 8. Puchner TC Jr, Zacharisen MC. A survey of antibiotic prescribing and knowledge of penicillin allergy. Ann Allergy Asthma Immunol 2002;88: 24-9. 9. Solensky R, Earl HS, Gruchalla RS. Clinical approach to penicillin-allergic patients: a survey. Ann Allergy Asthma Immunol 2000;84:329-33. 10. Wickern GM, Nish WA, Bitner AS, Freeman TM. Allergy to beta-lactams: a survey of current practices. J Allergy Clin Immunol 1994;94:725-31. 11. Prematta T, Shah S, Ishmael FT. Physician approaches to beta-lactam use in patients with penicillin hypersensitivity. Allergy Asthma Proc 2012;33:145-51. 12. Khan DA, Solensky R. Drug allergy. J Allergy Clin Immunol 2010;125: S126-37. 13. Jost BC, Wedner HJ, Bloomberg GR. Elective penicillin skin testing in a pediatric outpatient setting. Ann Allergy Asthma Immunol 2006;97:807-12. 14. Macy E, Shatz M, Lin C, Poon KY. The falling rate of positive penicillin skin tests from 1995 to 2007. Perm J 2009;13:12-8. 15. MacLaughlin EJ, Saseen JJ, Malone DC. Costs of beta-lactam allergies: selection and costs of antibiotics for patients with a reported beta-lactam allergy. Arch Fam Med 2000;9:722-6. 16. Sade K, Holtzer I, Levo Y, Kivity S. The economic burden of antibiotic treatment of penicillin-allergic patients in internal medicine wards of a general tertiary care hospital. Clin Exp Allergy 2003;33:501-6.
