Bericht des Nationalen Referenzzentrums für gramnegative Krankenhauserreger

Im Zeitraum vom 1. Januar 2022 bis zum 31. Dezember 2022 gab es im Nationalen Referenzzentrum (NRZ) für gramnegative Krankenhauserreger 9.548 Einsendungen von Bakterienisolaten. Dies entspricht einem Anstieg von fast 12 % im Vergleich zu 2021 und übertrifft das Vor-Pandemieniveau von 2019 (n = 9.369). Die Anzahl der Einsendungen lag bei durchschnittlich 796 Einsendungen pro Monat, die Isolate stammten aus 301 mikrobiologischen Laboren in Deutschland. Die Zahl der einsendenden Labore nahm im Vergleich zum Vorjahr (n = 283) ebenfalls zu. Wie das Epidemiologische Bulletin 27/2023 ausführt, stieg zudem Die Anzahl der Carbapenemase-Nachweise bei den bearbeiteten Isolaten stieg zudem auf den höchsten jemals im NRZ beobachteten Anstieg.Peer Reviewe

In Vitro Activity of Two Novel Antimicrobial Compounds on MDR-Resistant Clinical Isolates

International audienceThe development of novel antibiotics is mandatory to curb the growing antibiotic resistance problem resulting in difficult-to-treat bacterial infections. Here, we have determined the spectrum of activity of cystobactamids and chelocardins, two novel and promising classes of molecules with different modes of action. A panel of 297 clinically relevant Gram-negative and Gram-positive isolates with different antibiotic susceptibility profiles, going from wild type to multi- or even extremely drug resistant (MDR, XDR) and including carbapenem-resistant isolates, were tested using broth microdilution assays to determine the minimal inhibitory concentrations (MICs), MIC50s and MIC90s of two cystobactamids derivatives (CN-861-2 and CN-DM-861) and two chelocardin derivatives (CHD and CDCHD). Cystobactamids revealed potent activities on the majority of tested Enterobacterales (MIC50s ranging from 0.25 to 4 µg/mL), except for Klebsiella pneumoniae isolates (MIC50s is 128 µg/mL). Pseudomonas aeruginosa and Acinetobacter baumannii showed slightly higher MIC50s (4 µg/mL and 8 µg/mL, respectively) for cystobactamids. Chelocardins inhibited the growth of Enterobacterales and Stenotrophomas maltophilia at low to moderate MICs (0.25–16 µg/mL) and the chemically modified CDCHD was active at lower MICs. A. baumannii and P. aeruginosa were less susceptible to these molecules with MICs ranging from 0.5 to 32 µg/mL. These molecules show also interesting in vitro efficacies on clinically relevant Gram-positive bacteria with MICs of 0.125–8 µg/mL for cystobactamids and 0.5–8 µg/mL for chelocardins. Taken together, the cystobactamid CN-DM-861 and chelocardin CDCHD showed interesting antibiotic activities on MDR or XDR bacteria, without cross-resistance to clinically relevant antibiotics such as carbapenems, fluoroquinolones, and colistin