In vitro activities of omadacycline, eravacycline, cefiderocol, apramycin, and comparator antibiotics against Acinetobacter baumannii causing bloodstream infections in Greece, 2020-2021: a multicenter study.

Resistance of Acinetobacter baumannii to multiple clinically important antimicrobials has increased to very high rates in Greece, rendering most of them obsolete. The aim of this study was to determine the molecular epidemiology and susceptibilities of A. baumannii isolates collected from different hospitals across Greece. Single-patient A. baumannii strains isolated from blood cultures (n = 271), from 19 hospitals, in a 6-month period (November 2020-April 2021) were subjected to minimum inhibitory concentration determination and molecular testing for carbapenemase, 16S rRNA methyltransferase and mcr gene detection and epidemiological evaluation. 98.9% of all isolates produced carbapenemase OXA-23. The vast majority (91.8%) of OXA-23 producers harbored the armA and were assigned mainly (94.3%) to sequence group G1, corresponding to IC II. Apramycin (EBL-1003) was the most active agent inhibiting 100% of the isolates at ≤16 mg/L, followed by cefiderocol which was active against at least 86% of them. Minocycline, colistin and ampicillin-sulbactam exhibited only sparse activity (S <19%), while eravacycline was 8- and 2-fold more active than minocycline and tigecycline respectively, by comparison of their MIC50/90 values. OXA-23-ArmA producing A. baumannii of international clone II appears to be the prevailing epidemiological type of this organism in Greece. Cefiderocol could provide a useful alternative for difficult to treat Gram-negative infections, while apramycin (EBL-1003), the structurally unique aminoglycoside currently in clinical development, may represent a highly promising agent against multi-drug resistant A. baumanni infections, due to its high susceptibility rates and low toxicity.

Detection of metallo-ß-lactamase genes in clinical specimens by a commercial multiplex PCR system.

hyplex®-MBL ID Multiplex PCR-ELISA, a novel method for identifying metallo-ß-lactamase genes directly in clinical specimens, was evaluated using a consecutive collection of 326 samples from three hospitals in Greece characterized by high prevalence of VIM producers. The method exhibited high sensitivity (98.0%) and specificity (98.6%) and was proven reliable in detecting bla(VIM) genes in blood, urine, pus, and sputum samples that, as confirmed by conventional methods, contained various VIM-producing species. Future multicenter studies should be considered for the thorough evaluation of this method and its potential diagnostic utility.

Acute uncomplicated cystitis: from surveillance data to a rationale for empirical treatment.

The objectives of this study were to explore the epidemiological features and resistance rates in uropathogens isolated from cases of acute uncomplicated cystitis (AUC) in Greece, and subsequently to guide empirical treatment. Urine samples from outpatients aged >16 years were cultured and for each uropathogen isolated non-susceptibility to orally administered antimicrobial agents was defined. Demographic and clinical data were provided in questionnaire form. From January 2005 to March 2006 a total of 1936 non-duplicate positive urinary cultures were collected and 889 AUC cases were evaluated. Escherichia coli was the main aetiological agent (83%). In the AUC group, non-susceptibility rates for E. coli isolates were as follows: amoxicillin 25.8%; co-trimoxazole 19.2%; cefalothin 14.9%; nitrofurantoin 10.7%; amoxicillin/clavulanic acid 5.2%; nalidixic acid 6%; mecillinam 3.4%; ciprofloxacin 2.2%; cefuroxime 1.7%, and fosfomycin 1.6%. Amoxicillin and/or co-trimoxazole use in the previous 3 months was significantly associated with isolation of a co-trimoxazole-resistant E. coli isolate. The same applied for previous use of a fluoroquinolone agent and isolation of a ciprofloxacin-resistant E. coli isolate. In conclusion, increased co-trimoxazole non-susceptibility rates undermine its use as a first-line agent in empirical treatment, especially in cases of recent use of co-trimoxazole and/or amoxicillin. Fluoroquinolones display potent in vitro activity against community uropathogens, but prudent use is warranted for uncomplicated infections. Mecillinam and nitrofurantoin could serve as effective front-line agents in an effort to design fluoroquinolones-sparing regimens.