Pharmacist-Led Antimicrobial Stewardship and Antibiotic Use in Hospitalized Patients With COVID-19
Background: During the COVID-19 pandemic, a significant increase in the use of empiric antibiotic therapy has been observed especially in patients hospitalized with COVID-19. Improving antibiotic prescribing is one of the main goals of the antimicrobial stewardship program (ASP). The ASP pharmacists have a scope of practice that authorizes changes in anti-infective therapy.
Methods: We aimed to describe antibiotic prescribing in patients hospitalized with COVID-19 at Veterans Affairs Southern Nevada Healthcare System with a pharmacist-led ASP and to determine the prevalence of bacterial coinfection in this patient population. We performed a retrospective chart review of patients admitted to the facility from November 1, 2020, to January 31, 2021.
Results: A total of 199 patients were admitted to the hospital for laboratory-confirmed COVID-19 infection during the study period and 61 patients (31%) received ≥ 1 antibiotic on hospital admission and 138 (69%) did not receive antibiotics. Forty-seven patients (77%) had antibiotics discontinued by the ASP team within 72 hours of admission. Of the 199 admitted, 6 (3%) had microbiologically confirmed bacterial coinfection. Pseudomonas aeruginosa was the most common organism (3 sputum cultures) followed by Klebsiella oxytoca (2 sputum cultures). Sixteen patients (8%) developed a nosocomial infection during their hospital stay.
Conclusions: Up to 31% of patients hospitalized for COVID-19 infection received empiric antibiotic treatment for concern of bacterial coinfection. Pharmacist-led ASP led to early discontinuation of antibiotics in many patients. A thorough clinical workup to determine the risk of bacterial coinfection in patients with COVID-19 is important before starting empiric antibiotic therapy. It is essential to continue promoting the ASP during the COVID-19 pandemic to ensure responsible antibiotic use and prevent antimicrobial resistance.
Discussion
Prospective audit and feedback and preauthorization are recommended in guidelines as “core components of any stewardship program.”9 At VASNHS, the ASP performs daily prospective audits with intervention and feedback. Efforts have been made to maintain daily ASP activities during the pandemic. This study aimed to describe antibiotic prescribing for patients hospitalized with COVID-19 in a pharmacist-led ASP setting. It was found that up to 31% of the patients received ≥ 1 antibiotic on admission for empiric treatment of bacterial coinfection. About half of these patients met the SIRS criteria. Most of these patients received ceftriaxone and azithromycin for concern of CAP. ASP discontinued antibiotics within 72 hours in most of the patients. Chart review and discussion with ID physicians and/or hospitalists determined the probability of bacterial coinfection as well as any potential complication or patient-specific risk factor. It is important to note that most patients who received antibiotics on admission had ≥ 1 PCT level and up to 46% of them had a PCT level > 0.25. However, according to Relph and colleagues, PCT may not be a reliable indicator of bacterial infection in severe viral diseases with raised interleukin-6 levels.10 An elevated PCT level should not be the sole indicator for empiric antibiotic treatment.
Study findings confirmed the low prevalence of bacterial coinfection in patients hospitalized with COVID-19. The overuse of empiric antibiotics in a patient population unlikely to present with bacterial coinfection is concerning. It is essential to continue promoting antimicrobial stewardship during the COVID-19 pandemic to ensure appropriate and responsible antimicrobial prescribing. A thorough clinical assessment consisting of comorbidities, clinical symptoms, radiologic and microbiologic findings, as well as other relevant workup or biomarker results is crucial to determine whether the antibiotic is strongly indicated in patients hospitalized with COVID-19. Empiric antibiotic therapy should be considered only in patients with clinical findings suggestive of bacterial coinfection.
Limitations
Limitations of our study included the study design (single-center, retrospective review, lack of comparative group) and small sample size with a 3-month study period. In addition, respiratory cultures are not commonly obtained in patients who present with mild-to-moderate CAP. Using culture results solely to confirm bacterial coinfection in patients with COVID-19 could have underestimated the prevalence of bacterial infection. Developing diagnostic criteria that include clinical signs and symptoms, imaging findings, and laboratory results as well as culture results would help to better assess the presence of bacterial coinfection in this patient population.
Conclusions
The study findings showed that up to 30% of patients hospitalized for COVID-19 infection received empiric antibiotic treatment for concern of bacterial coinfection. A pharmacist-led ASP provided interventions, including early discontinuation of antibiotics in 77% of these patients.
A low prevalence of bacterial coinfection (3%) in patients hospitalized with COVID-19 also was reported. A thorough clinical workup to determine the risk of bacterial coinfection in patients with COVID-19 is important before starting empiric antibiotic therapy. Continuing to promote the ASP during the COVID-19 pandemic to ensure responsible antibiotic use and prevent antimicrobial resistance is essential.
