Clinical outcomes of temocillin use for invasive Enterobacterales infections: a single-centre retrospective analysis

Katie L Heard; Kieran Killington; Nabeela Mughal; Luke S P Moore; Stephen Hughes

doi:10.1093/jacamr/dlab005

Clinical outcomes of temocillin use for invasive Enterobacterales infections: a single-centre retrospective analysis

JAC Antimicrob Resist. 2021 Feb 14;3(1):dlab005. doi: 10.1093/jacamr/dlab005. eCollection 2021 Mar.

Authors

Katie L Heard¹, Kieran Killington¹, Nabeela Mughal^{1

2

3}, Luke S P Moore^{1

2

3}, Stephen Hughes¹

Affiliations

¹ Chelsea and Westminster NHS Foundation Trust, 369 Fulham Road, London SW10 9NH, UK.
² North West London Pathology, Imperial College Healthcare NHS Trust, Fulham Palace Road. London W6 8RF, UK.
³ National Institute for Health Research Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Imperial College London, Hammersmith Campus, Du Cane Road, London W12 0NN, UK.

Abstract

Background: With increasing frequency of resistant Gram-negative bacteria, temocillin has potential utility in reducing carbapenem use. The 2020 EUCAST guideline changes temocillin breakpoints and reclassifies isolates with an MIC of 0.001-16 mg/L as 'susceptible, increased exposure' necessitating 6 g/day rather than the previous 4 g/day, associated with significant cost implications.

Objectives: We explore the clinical utility and treatment failure rate of temocillin at 4 g/day dosing.

Methods: All adult inpatient electronic prescriptions of temocillin (3 days or greater) from March 2016 to October 2019 were retrieved using a clinical decision support system (ICNET^®). Treatment success was defined as survival, no switch to broad-spectrum agent for the same indication and no subsequent recrudescence of infection, occurring within 30 days.

Results: Temocillin was used in 205 eligible patient-episodes, median age 79 years (IQR : 71-87 years), 42.4% female. Median temocillin course length was 5.9 days (IQR : 4.6-7.8 days). Indications for use: urinary tract infection (UTI) (n = 141), pneumonia (n = 53), other (n = 11). In total, 144 (70.2%) patients had targeted treatment; 74 (36.1%) against Escherichia coli, 70 (34.4%) other Enterobacterales. A total of 130 (63%) patients received 4 g/day; the remaining patients had reduced renal function with dosing in accordance with guidance. Overall temocillin treatment success was 79.5%; highest when used to treat UTI 85.8% (versus 67.9% in respiratory infections, P = 0.008). Empirical treatment demonstrated 82.0% (50/61) success [versus 78.5% (113/144) among targeted treatment, P = 0. 71].

Conclusions: Temocillin at 4 g/day is an effective and safe alternative in treating patients with Gram-negative infections, but should be considered in the context of patient age and comorbidities. Increased dosing or alternate strategies may be indicated when the infection is not of a urinary source.