# Oral quinolones versus intravenous β-lactam for the treatment of acute focal bacterial nephritis: a retrospective cohort study

## TL;DR

This study found that oral quinolones are as effective as intravenous β-lactam antibiotics for treating acute focal bacterial nephritis, with fewer side effects.

## Contribution

The study provides evidence that oral quinolones can be a safe and effective alternative to IV β-lactam antibiotics for AFBN.

## Key findings

- Oral quinolones and IV β-lactam antibiotics showed similar effectiveness in treating AFBN.
- Oral quinolones had fewer adverse events, such as phlebitis and catheter-related bacteraemia.
- Escherichia coli was the most common microorganism isolated in AFBN cases.

## Abstract

Evidence regarding the best antibiotic regimen and the route of administration to treat acute focal bacterial nephritis (AFBN) is scarce. The aim of the present study was to compare the effectiveness of intravenous (IV) β-lactam antibiotics versus oral quinolones.

This is a retrospective single centre study of patients diagnosed with AFBN between January 2017 and December 2018 in Hospital Universitari Vall d’Hebron, Barcelona (Spain). Patients were identified from the diagnostic codifications database. Patients treated with oral quinolones were compared with those treated with IV β-lactam antibiotics. Therapeutic failure was defined as death, relapse, or evolution to abscess within the first 30 days.

A total of 264 patients fulfilled the inclusion criteria. Of those, 103 patients (39%) received oral ciprofloxacin, and 70 (26.5%) IV β-lactam. The most common isolated microorganism was Escherichia coli (149, 73.8%) followed by Klebsiella pneumoniae (26, 12.9%). Mean duration of treatment was 21.3 days (SD 7.9). There were no statistical differences regarding therapeutic failure between oral quinolones and IV β-lactam treatment (6.6% vs. 8.7%, p = 0.6). Out of the 66 patients treated with intravenous antibiotics, 4 (6.1%) experienced an episode of phlebitis and 1 patient (1.5%) an episode of catheter-related bacteraemia.

When susceptible, treatment of AFBN with oral quinolones is as effective as IV β-lactam treatment with fewer adverse events.