Assignment 1 forum

Clinical gap: 

Many patients who report beta-lactam antibiotic allergies do not receive appropriate evaluation of their unverified beta-lactam allergies.  

Background and consequence of this gap on clinical outcomes:

Over 90% of patients with a listed beta-lactam antibiotic allergy can safely receive beta-lactam antibiotics.¹ It is recommended that patients with a listed beta-lactam antibiotic allergy receive appropriate beta-lactam antibiotic allergy evaluation to prevent unnecessary avoidance of a wide range of beta-lactam antibiotics and overuse of non-beta lactam antibiotics.^2,3

Reported penicillin allergy is associated with avoidance of a wide range of beta-lactam antibiotics, resulting in overuse of non-beta lactam antibiotics,⁴ higher medical costs,^5–7 longer hospital stays,⁸ and higher rates of infections with vancomycin-resistant enterococcus (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and Clostridium difficile.⁸ Perioperative use of alternative non-beta lactam antibiotics in patients with reported penicillin allergy is associated with increased surgical site infection risk.⁹

Clinical Intervention: 

I am interested in implementing and investigating the effectiveness of a clinical, evidence-based beta-lactam allergy evaluation guideline for inpatients at UCSF with reported but unverified beta-lactam antibiotic allergy.  

Support and evidence for efficacy of intervention:

Beta-lactam antibiotic allergy evaluation consists of obtaining patients’ beta-lactam allergy history and determining which beta-lactam antibiotics are safe to use. Cross-reactivity rates between different beta-lactam antibiotics are low and even patients with true penicillin allergy can safely receive many cephalosporin and carbapenem antibiotics.^10,11 In specific situations (i.e., when the original reaction was to penicillin and a patient needs a penicillin antibiotic), penicillin skin testing is a key step in the beta-lactam allergy evaluation. Penicillin skin testing is a validated test that accurately identifies patients who can safely receive penicillin antibiotics (negative predictive value approaching 99%).¹²   

The American Board of Internal Medicine Choosing Wisely program, the American Academy of Allergy and Immunology, the Infectious Disease Society of America (IDSA), and the Society for Healthcare Epidemiology of America have written guidelines supporting appropriate allergy assessments for patients with unverified beta-lactam allergy.^2,3,13 However, the IDSA does rate their recommendation that antibiotic stewardship programs promote allergy beta-lactam allergy assessments as weak, because beta-lactam allergy assessments have not been studied in depth as a primary antibiotic stewardship program intervention.¹³  

The optimal strategy to implement appropriate beta-lactam allergy assessments is still being determined. Different intervention strategies have been successful at decreasing use of beta-lactam alternatives and increasing more clinically and cost-effective therapy. Investigated intervention strategies include the following:

1. A guideline that helps general inpatient providers obtain a beta-lactam allergy history and identify which beta-lactams are safe to use with or without penicillin skin testing.¹⁴
   
2. Proactive penicillin skin testing in hospitalized patients on beta-lactam alternatives with unverified penicillin allergy.¹
   
3. Proactive penicillin skin testing in outpatients with unverified penicillin allergy.¹⁵  
   
4. Penicillin skin testing as part of an antimicrobial stewardship program.^16–18
   

While there is strong data that beta-lactam allergy evaluations decrease non-beta lactam antibiotic use, there is less data regarding the impact of beta-lactam allergy evaluations on cost savings, length of hospital stay, and rates of infections with multi-drug resistant organisms.   

Evidence that intervention is not being used:

The fact that listed penicillin allergy is associated with overuse of non-beta lactam antibiotics suggest that beta-lactam allergy evaluations are not being performed routinely.⁴ Since an optimal implementation strategy for beta-lactam allergy evaluation has not been defined, it follows that a largescale study investigating utilization of said undetermined optimal implementation strategy has not been performed. At UCSF, specifically, the proposed intervention utilization is near 0% since the UCSF beta-lactam allergy evaluation guideline was created and approved earlier this year.

1.        Chen, J. R., Tarver, S. A., Alvarez, K. S., Tran, T. & Khan, D. A. A Proactive Approach to Penicillin Allergy Testing in Hospitalized Patients. J. Allergy Clin. Immunol. Pract.5,686–693 (2017).

2.        Penicillin Allergy in Antibiotic Resistance Workgroup, D. M., Castells, M. C., Khan, D. A., Macy, E. M. & Murphy, A. W. Penicillin Allergy Testing Should Be Performed Routinely in Patients with Self-Reported Penicillin Allergy. J. allergy Clin. Immunol. Pract.5,333–334 (2017).

3.        Macy, E. Penicillin and Beta-Lactam Allergy: Epidemiology and Diagnosis. Curr. Allergy Asthma Rep.14,476 (2014).

4.        Lee, C. E. et al.The incidence of antimicrobial allergies in hospitalized patients: implications regarding prescribing patterns and emerging bacterial resistance. Arch. Intern. Med.160,2819–22 (2000).

5.        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. Allergy33,501–6 (2003).

6.        MacLaughlin, E. J. Costs of beta-Lactam Allergies: Selection and Costs of Antibiotics for Patients With a Reported beta-Lactam Allergy. Arch. Fam. Med.9,722–726 (2000).

7.        Kraemer, M. J., Caprye-Boos, H. & Berman, H. S. Increased use of medical services and antibiotics by children who claim a prior penicillin sensitivity. West. J. Med.146,697–700 (1987).

8.        Macy, E. & Contreras, R. Health care use and serious infection prevalence associated with penicillin ‘allergy’ in hospitalized patients: A cohort study. J. Allergy Clin. Immunol.133,790–796 (2014).

9.        Blumenthal, K. G. et al.The Impact of a Reported Penicillin Allergy on Surgical Site Infection Risk. Clin. Infect. Dis.66,329–336 (2018).

10.      Pichichero, M. E. & Casey, J. R. Safe use of selected cephalosporins in penicillin-allergic patients: A meta-analysis. Otolaryngol. Neck Surg.136,340–347 (2007).

11.      Pichichero, M. E. & Zagursky, R. Penicillin and cephalosporin allergy. Ann. Allergy. Asthma Immunol.112,404–12 (2014).

12.      Park, M. A. & Li, J. T. C. Diagnosis and Management of Penicillin Allergy. Mayo Clin. Proc.80,405–410 (2005).

13.      Barlam, T. F. et al.Implementing an Antibiotic Stewardship Program: Guidelines by the Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America. Clin. Infect. Dis.62,e51–e77 (2016).

14.      Blumenthal, K. G. et al.Impact of a clinical guideline for prescribing antibiotics to inpatients reporting penicillin or cephalosporin allergy. Ann. Allergy. Asthma Immunol.115,294–300.e2 (2015).

15.      Sundquist, B. K., Bowen, B. J., Otabor, U., Celestin, J. & Sorum, P. C. Proactive penicillin allergy testing in primary care patients labeled as allergic: outcomes and barriers. Postgrad. Med.129,915–920 (2017).

16.      Rimawi, R. H. et al.The impact of penicillin skin testing on clinical practice and antimicrobial stewardship. J. Hosp. Med.8,341–345 (2013).

17.      Heil, E. L. et al.Implementation of an Infectious Disease Fellow-Managed Penicillin Allergy Skin Testing Service. Open forum Infect. Dis.3,ofw155 (2016).

18.      Jones, B. M. & Bland, C. M. Penicillin skin testing as an antimicrobial stewardship initiative. Am. J. Health. Syst. Pharm.74,232–237 (2017).