OVERUSE OF ANTIBIOTICS FOR ASYMPTOMATIC BACTERIURIA IN A UNIVERSITY TEACHING ...

85 Pages·2013·0.48 MB·English

by  Webster, Emily C

OVERUSE OF ANTIBIOTICS FOR ASYMPTOMATIC BACTERIURIA IN A
UNIVERSITY TEACHING HOSPITAL
by
Emily Christine Webster
BS, BA, University of Texas at Austin, 2009
Submitted to the Graduate Faculty of
Graduate School of Public Health in partial fulfillment
of the requirements for the degree of
Master of Public Health
University of Pittsburgh
2013
UNIVERSITY OF PITTSBURGH
GRADUATE SCHOOL OF PUBLIC HEALTH

This thesis was presented

by

Emily C. Webster

It was defended on
March 25, 2013
and approved by
Thesis Chair: Linda Rose Frank, PhD, MSN, ACRN, FAAN Associate Professor of Public
Health, Medicine, & Nursing, Department of Infectious Diseases and Microbiology,
Graduate School of Public Health, University of Pittsburgh

Committee Member: Jeremy Martinson, DPhil, Assistant Professor, Department of
Infectious Diseases and Microbiology, Graduate School of Public Health, University of
Pittsburgh

Committee Member: Carlene A. Muto, MD, Associate Professor, Department of Medicine,
University of Pittsburgh

Committee Member: Susan J. Skledar, RPh, MPH, FASHP, Associate Professor, School of
Pharmacy, University of Pittsburgh

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Copyright © by Emily Webster
2013
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Linda Rose Frank, PhD, MSN
OVERUSE OF ANTIBIOTICS FOR ASYMPTOMATIC BACTERIURIA IN A
UNIVERSITY TEACHING HOSPITAL
Emily Webster, MPH
University of Pittsburgh, 2013
ABSTRACT
Public Health Significance: Antibiotic resistance is an increasingly important public
health issue. Antibiotic resistance emerges from antibiotic use, and unnecessary and incorrect
usage of these drugs is accelerating the increasing prevalence and severity of resistant organisms.
Misdiagnosis of a urinary tract infection is one of the main causes of unnecessary antibiotic use.
Problem Statement: Antibiotic overuse can lead to adverse patient outcomes, and
antibiotics should be used judiciously and according to published treatment guidelines. Many
clinicians at healthcare facilities do not adhere to treatment guidelines for asymptomatic
bacteriuria; often clinicians incorrectly give asymptomatic patients a diagnosis of a urinary tract
infection which has been shown to yield high rates of unnecessary antibiotic use.
Objective: To determine whether the University Teaching Hospital adheres to IDSA
treatment guidelines for UTI and ABU for this cohort of patients and explore the relationship
between failure to adhere to IDSA guidelines of treatment of ABU and excess pharmaceutical
costs.
Setting: A public acute care teaching hospital affiliated with a local state university
in central Texas.
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Participants: Patients included in the cohort were at least 18 years of age and admitted
to the hospital for >2 days between the dates of September 2011 and February 2012 and
diagnosed with a UTI.
Main outcome measures: Frequency of patients who were incorrectly diagnosed with a
UTI who were asymptomatic and treated inappropriately, total number of antibiotics used for
these patients, and the costs of these unnecessary antibiotics.
Results: Of the 88 included patients, 26 patients (29.5%) had no documentation of any
symptoms of a UTI but were diagnosed and treated inappropriately. There were a total of 353
doses given to these patients for a total excess cost of $512.45. Eleven patients (12.5%)
were classified as a “questionable” diagnosis of a UTI because documentation was not clear
enough to indicate if the patient had a UTI or ABU. There were a total of 234 doses given to
these patients for a total excess cost of $271.76.
Conclusion: Based upon this sample, clinicians in this facility do not strictly adhere to
IDSA treatment guidelines. The clinicians could benefit from an antibiotic stewardship program
or an educational intervention to improve adherence to the current IDSA guidelines.
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TABLE OF CONTENTS
ACKNOWLEDGEMENTS ..................................................................................................... XII
1.0 INTRODUCTION ........................................................................................................ 1
2.0 BACKGROUND .......................................................................................................... 3
2.1 ANTIBIOTICS AND THE RISE OF ANTIBIOTIC RESISTANCE ............. 3
2.2 EFFECTS OF INAPPROPRIATE ANTIBIOTIC USE .................................. 6
2.2.1 Adverse Reactions to Antibiotics.................................................................... 7
2.2.2 Clostridium difficle Infections ......................................................................... 8
2.2.3 Mortality ......................................................................................................... 10
2.2.4 Length of Stay ................................................................................................ 11
2.2.5 Costs ................................................................................................................ 12
2.2.5.1 Costs of antibiotics .............................................................................. 13
2.2.5.2 Hospitalization Costs .......................................................................... 13
2.2.5.3 Costs of C. difficile infections ............................................................. 14
2.2.5.4 Medicare Retaliates ............................................................................. 15
2.2.6 Urinary Tract Infections and Asymptomatic Bacteriuria ......................... 15
3.0 METHODS ................................................................................................................. 25
3.1.1 Study Objectives ............................................................................................ 25
3.1.2 Study Design ................................................................................................... 25
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3.1.3 Study Area ...................................................................................................... 26
3.1.4 Study Population............................................................................................ 26
3.1.4.1 Eligibility Criteria ............................................................................... 26
3.1.4.2 Inclusion Criteria ................................................................................ 28
3.1.4.3 Exclusion Criteria ............................................................................... 28
3.1.4.4 The Population .................................................................................... 28
3.1.5 Data Collection ............................................................................................... 30
3.1.6 Data analysis .................................................................................................. 31
4.0 RESULTS ................................................................................................................... 32
4.1 EXCLUDED GROUP ....................................................................................... 32
4.2 INCLUDED PATIENTS ................................................................................... 33
4.2.1 UTI Group ...................................................................................................... 34
4.2.2 ABU Group .................................................................................................... 35
4.2.3 Questionable Group ...................................................................................... 41
5.0 DISCUSSION ............................................................................................................. 46
5.1 SUMMARY OF RESULTS .............................................................................. 46
5.2 ANTIBIOTIC STEWARDSHIP ...................................................................... 49
5.2.1 Program Strategies and Elements ................................................................ 50
5.2.2 Interventions at Other Facilities for ABU Overtreatment ........................ 55
5.2.3 Future Recommendations ............................................................................. 57
5.2.4 Limitations ..................................................................................................... 57
5.2.5 Final Notes ...................................................................................................... 59
6.0 CONCLUSION ........................................................................................................... 61
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APPENDIX A: CDC AND NHSN UTI DEFINITIONS .......................................................... 62
APPENDIX B: ABU/UTI RETROSPECTIVE STUDY DATA EXTRACTION FORM .... 66
APPENDIX C: COSTS OF ANTIBIOTICS FROM UTH PHARMACY ............................. 68
BIBLIOGRAPHY ....................................................................................................................... 70
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LIST OF TABLES
Table 1: ESKAPE vs. ESCAPE Organisms ................................................................................... 6
Table 2: Mortality for Resistant Organisms compared to Susceptible and Uninfected Patients .. 10
Table 3: Increased length of hospital stay due to antibiotic resistant infections .......................... 12
Table 4: Mean Attributable Hospital Costs due to Resistant Infections ....................................... 14
Table 5: IDSA recommendations for diagnosis and treatment of ABU in adults ........................ 18
Table 6: A summary of prevalence of ABU in different populations........................................... 19
Table 7: ICD-9 Codes Eligible for Study ..................................................................................... 27
Table 8: Reasons for Exclusion from Study ................................................................................. 32
Table 9: Summary of demographics of included patients ............................................................ 33
Table 10: Organisms Isolated from Patients with UTIs................................................................ 34
Table 11: Symptoms seen in patients with UTIs .......................................................................... 35
Table 12: Organisms isolated from patients with ABU ................................................................ 36
Table 13: Symptoms in patients with ABU explained by other reasons ...................................... 36
Table 14: Reasons for screening in patients with ABU ................................................................ 37
Table 15: Reasons for treatment for patients with ABU............................................................... 38
Table 16: Time between culture and treatment in patients with ABU ......................................... 38
Table 17: Defined Daily Doses for patients with ABU ................................................................ 39
Table 18: Pharmaceutical costs of patients with ABU ................................................................. 40
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Table 19: Organisms isolated from patients with a questionable UTI diagnosis ......................... 41
Table 20: Symptoms seen in patients with a questionable UTI diagnosis .................................... 41
Table 21: Reasons for screening and treatment for UTI in patients with questionable UTI
diagnosis ....................................................................................................................................... 42
Table 22: Time between culture and treatment in patients with questionable UTI diagnosis ...... 42
Table 23: Defined Daily Doses for patients with questionable UTI diagnosis............................. 44
Table 24: Pharmaceutical costs of patients with questionable UTI diagnosis .............................. 45
Table 25: Summary of ABU overtreatment rates found in literature ........................................... 48
Table 26: Summary of Existing Interventions to reduce inappropriate treatment of ABU .......... 56
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