Cefmetazole is active against extended-spectrum β-lactamase-producing Escherichia coli (ESBLEC) and is a potential candidate for
carbapenem-sparing
therapy. This multicenter, observational study included patients hospitalized for invasive
urinary tract infection due to ESBLEC between March 2020 and November 2021
at 10 facilities in Japan, for whom either
cefmetazole or
meropenem was initiated as a definitive
therapy within 96 h of culture collection and continued for at least 3 d. Outcomes included clinical and microbiological effectiveness, recurrence within 28 d, and all-cause mortality (14 d, 30 d, in-hospital). Outcomes were adjusted for the inverse probability of propensity scores for receiving
cefmetazole or
meropenem. Eighty-one and forty-six patients were included in the
cefmetazole and
meropenem groups, respectively.
Bacteremia accounted for 43% of the
cefmetazole group, and 59% of the
meropenem group. The crude clinical effectiveness, 14 d, 30 d, and in-hospital mortality for patients in the
cefmetazole and
meropenem groups were 96.1% vs 90.9%, 0% vs 2.3%, 0% vs 12.5%, and 2.6% vs 13.3%, respectively. After propensity score adjustment, clinical effectiveness, the risk of in-hospital mortality, and the risk of recurrence were similar between the two groups (P = 0.54, P = 0.10, and P = 0.79, respectively). In all cases with available data (
cefmetazole : n = 61,
meropenem : n = 22), both drugs were microbiologically effective. In all isolates, bla CTX-M was detected as the extended-spectrum β-lactamase gene. The predominant CTX-M subtype was CTX-M-27 (47.6%).
Cefmetazole showed clinical and bacteriological effectiveness comparable to
meropenem against invasive
urinary tract infection due to ESBLECs.