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Published on: July 18, 2017
Prolonged fever is not a reason to change antibiotics among patients with uncomplicated community-acquired acute
Young-Rock Jang1, Joong Sik Eom1, Wookyung Chung2
1Division of Infectious Disease.
Abstract:
The study aimed to determine the pattern of fever resolution among febrile patients undergoing treatment for acute pyelonephritis (APN) and prove that switching therapy based solely on persistent fever beyond 72 hours of antibiotics treatment may be unwarranted.For the purpose of this study, non-responders were defined as those patients who had a persistent fever over 72 hours after the initiation of antibiotic therapy. Responders were defined as those patients who became afebrile in less than 72 hours after the initiation of antibiotic therapy. Clinical cure was defined as the complete resolution of all symptoms during antibiotic therapy without recurrence during the follow-up period.A total of 843 female patients with uncomplicated community-acquired APN met all inclusion criteria. The non-responder group comprised of 248 patients (29%), and the remaining patients constituted the responder group. The median initial C-reactive protein level was higher (15.6 mg/dl vs 12.6 md/dl, P < .001) and bacteremia was more frequent (31% vs 40%, P = .001) in the non-responder group. Escherichia coli (E. coli) was the most common pathogen in both groups; there was no significant difference between the groups in the etiology of APN. Antimicrobial resistance and extended spectrum β-lactamase producing strains had an increasing trend in the non-responder group but there was no significant difference between the groups.This study shows that it is difficult to identify patients at risk of uncomplicated community-acquired APN by antibiotic-resistant pathogens based exclusively on persistent fever. Patients with a prolonged fever for more than 72 hours show similar antibiotic susceptibility patterns and are not associated with adverse treatment outcomes. Therefore, switching of current antibiotics to broad-spectrum antibiotics should be reserved in this patient population until antibiotic susceptibility test results are available.
Insights
Persistent fever beyond 72 hours in acute pyelonephritis (APN) patients doesn't necessitate immediate antibiotic changes. Most patients with prolonged fever show similar antibiotic susceptibility and good outcomes, suggesting a wait for susceptibility results is best.
Area of Science:
- Infectious Diseases
- Internal Medicine
- Pharmacology
Background:
- Acute pyelonephritis (APN) is a common upper urinary tract infection.
- Fever is a primary indicator of infection but its resolution pattern can vary.
- Current clinical practice sometimes involves switching antibiotics based on persistent fever.
Purpose of the Study:
- To investigate the fever resolution patterns in patients with acute pyelonephritis (APN) treated with antibiotics.
- To evaluate whether persistent fever beyond 72 hours warrants a change in antibiotic therapy.
- To determine if prolonged fever correlates with adverse outcomes or antibiotic resistance in APN.
Main Methods:
- Retrospective analysis of 843 female patients with uncomplicated community-acquired APN.
- Categorization of patients into responders (afebrile <72 hours) and non-responders (fever >72 hours).
- Comparison of clinical characteristics, C-reactive protein levels, bacteremia rates, and antimicrobial susceptibility between groups.
Main Results:
- 29% of patients were classified as non-responders (fever >72 hours).
- Non-responders had higher initial C-reactive protein levels and more frequent bacteremia.
- No significant differences in APN etiology or antimicrobial resistance patterns were found between responders and non-responders.
Conclusions:
- Persistent fever beyond 72 hours in APN does not reliably predict antibiotic resistance or adverse outcomes.
- Switching antibiotic therapy solely based on persistent fever is likely unwarranted.
- Antibiotic susceptibility testing results should guide treatment changes in APN patients with prolonged fever.
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