Erratum to: Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA)

A Proposal for a Classification Guiding the Selection of Appropriate Antibiotic Therapy for Intra-Abdominal Infections

Adequately controlling the source of infection and prescribing appropriately antibiotic therapy are the cornerstones of the management of patients with intra-abdominal infections (IAIs). Correctly classifying patients with IAIs is crucial to assessing the severity of their clinical condition and deciding the strategy of the treatment, including a correct empiric antibiotic therapy. Best practices in prescribing antibiotics may impact patient outcomes and the cost of treatment, as well as the risk of “opportunistic” infections such as Clostridioides difficile infection and the development and spread of antimicrobial resistance. This review aims to identify a correct classification of IAIs, guiding clinicians in the selection of the best antibiotic therapy in patients with IAIs.

Investigation of OXA-23, OXA-24, OXA-40, OXA-51, and OXA-58 Genes in Carbapenem-Resistant Escherichia coli and Klebsiella pneumoniae Isolates from Patients with Urinary Tract Infections

Background: Escherichia coli and Klebsiella pneumoniae are frequently responsible for urinary tract infections (UTIs). The high rate of carbapenem resistance in Enterobacteriaceae has become a global therapeutic concern. Objectives: The study investigated OXA-23, OXA-24, OXA-40, OXA-51, and OXA-58 genes in uropathogenic E. coli and K. pneumoniae isolates. Methods: We isolated 500 uropathogenic isolates of E. coli and K. pneumoniae from patients at Milad Hospital, Tehran, Iran. Antibiotic susceptibility testing was performed using a strip-test method, and the carbapenem-nonsusceptoble isolates were confirmed with an automated antibiotic sensitivity testing system. The OXA genes were determined by multiplex PCR. Molecular typing was performed by multilocus variable-number tandem repeat (VNTR) analysis (MLVA). Results: Out of 500 isolates, 40 (8%) were detected as carbapenem-resistant, including 13 E. coli and 27 K. pneumoniae. All carbapenem-resistant isolates were ESBL-producing and resistant to ceftriaxone, ciprofloxacin, meropenem, ceftazidime, and amoxicillin-clavulanate. Moreover, 46.1% and 26% of carbapenem-insensitive E. coli and K. pneumoniae isolates carried a beta-lactamase-producing gene associated with the OXA-23-like group. Finally, E. coli and K. pneumoniae isolates were divided into two and three MLVA patterns, respectively. Conclusions: This is the first report of OXA-51, 58, and 24 carbapenemases in clinical isolates of E. coli and K. pneumoniae from UTI patients in Iran. Significant differences were seen in OXA-51, 58, and 24 genes between carbapenem-insensitive and carbapenem-sensitive E. coli and K. pneumoniae isolates. Molecular typing suggested the vertical transmission of resistance genes.

Serum and peritoneal exudate concentrations after high doses of β-lactams in critically ill patients with severe intra-abdominal infections: an observational prospective study

BACKGROUND

Critically ill patients with severe intra-abdominal infections (IAIs) requiring surgery may undergo several pharmacokinetic (PK) alterations that can lead to β-lactam underdosage.

OBJECTIVES

To measure serum and peritoneal exudate concentrations of β-lactams after high doses and optimal administration schemes.

METHODS

This observational prospective study included critically ill patients with suspicion of IAI who required surgery and a β-lactam antibiotic as empirical therapy. Serum and peritoneal exudate concentrations were measured during surgery and after a 24 h steady-state period. The PK/pharmacodynamic (PD) target was to obtain serum β-lactam concentrations of 100% fT>4×MIC based on a worst-case scenario (based on the EUCAST highest epidemiological cut-off values) before bacterial documentation (a priori) and redefined following determination of the MIC for the isolated bacteria (a posteriori). Registered with ClinicalTrials.gov (NCT03310606).

RESULTS

Forty-eight patients were included with a median (IQR) age of 64 (53-74) years and a SAPS II of 40 (32-65). The main diagnosis was secondary nosocomial peritonitis. Piperacillin/tazobactam was the most administered β-lactam antibiotic (75%). The serum/peritoneal piperacillin/tazobactam ratio was 0.88 (0.64-0.97) after a 24 h steady-state period. Prior to bacterial documentation, 16 patients (33.3%) achieved the a priori PK/PD target. The identification of microorganisms was available for 34 patients (71%). Based on the MIC for isolated bacteria, 78% of the patients achieved the serum PK/PD target.

CONCLUSIONS

In severe IAIs, high doses of β-lactams ensured 100% fT>4×MIC in the serum for 78% of critically ill patients with severe IAIs within the first 24 h. In order to define optimal β-lactam dosing, the PK/PD target should take into account the tissue penetration and local ecology.

Surgeon-led 7-VINCut Antibiotic Stewardship Intervention Decreases Duration of Treatment and Carbapenem Use in a General Surgery Service

Antibiotic stewardship programs optimize the use of antimicrobials to prevent the development of resistance and improve patient outcomes. In this prospective interventional study, a multidisciplinary team led by surgeons implemented a program aimed at shortening the duration of antibiotic treatment <7 days. The impact of the intervention on antibiotic consumption adjusted to bed-days and discharges, and the isolation of multiresistant bacteria (MRB) was also studied. Furthermore, the surgeons were surveyed regarding their beliefs and feelings about the program. Out of 1409 patients, 40.7% received antibiotic therapy. Treatment continued for over 7 days in 21.5% of cases, and, as can be expected, source control was achieved in only 48.8% of these cases. The recommendations were followed in 90.2% of cases, the most frequent being to withdraw the treatment (55.6%). During the first 16 months of the intervention, a sharp decrease in the percentage of extended treatments, with R2 = 0.111 was observed. The program was very well accepted by surgeons, and achieved a decrease in both the consumption of carbapenems and in the number of MRB isolations. Multidisciplinary stewardship teams led by surgeons seem to be well received and able to better manage antibiotic prescription in surgery.

Twenty-four hour versus extended antibiotic administration after surgery in complicated appendicitis: A randomized controlled trial

BACKGROUND

Recent investigations noted noninferiority in short-course antimicrobial treatments following source control in abdominal infections. We set out to investigate noninferiority of a short and fixed (24 hours) antibiotic administration compared to extended treatment after source control in complicated appendicitis in a prospective single-center open-label randomized controlled trial.

METHODS

After Institutional Review Board (IRB) approval, all consecutive adult patients (age, ≥ 18 years) with complicated appendicitis including gangrenous appendicitis, perforated appendicitis, and appendicitis with periappendicular abscess between May 2016 and February 2018 were randomly allocated to antibacterial therapy limited to 24 hours (short) vs. >24 hours (extended) administration after appendectomy. Primary outcomes included composite postoperative complications and Comprehensive Complication Index (CCI). Secondary outcome was hospital length of stay (HLOS). Follow-up analysis at 1 month was conducted per intention and per protocol.

RESULTS

A total of 80 patients were enrolled with 39 and 41 cases allocated to the short and the extended therapy group, respectively. Demographic profile and disease severity was similar between the study groups. Overall rate of complications was 17.9% and 29.3% in the short and extended group, respectively (p = 0.23). Mean CCI did not differ between the study groups (p = 0.29). Hospital length of stay was significantly reduced in the short therapy group (61 ± 34 hours vs. 81 ± 40 hours, p = 0.005).

CONCLUSION

In the current prospective randomized investigation, the short (24 hours) antibiotic administration following appendectomy did not result in a worse primary outcome in complicated appendicitis. The short interval administration resulted in a significant reduction in HLOS with a major cost-saving and antibacterial stewardship perspective.

LEVEL OF EVIDENCE

Therapeutic Level IV.