Antimicrobial Activity of Dalbavancin and Comparators against Staphylococcus aureus Causing Pneumonia in Patients with and without Cystic Fibrosis

Int J Infect Dis. 2021 Apr 17:S1201-9712(21)00362-3. doi: 10.1016/j.ijid.2021.04.051. Online ahead of print.

ABSTRACT

We evaluated the activities of dalbavancin and comparator agents against Staphylococcus aureus isolated from the lower respiratory tract of cystic fibrosis (CF) and non-CF patients with pneumonia. Bacterial isolates (n = 357) were collected from CF patients in 36 medical centers worldwide (2018-2019) and susceptibility tested by reference broth microdilution method. Susceptibility results from these isolates were compared to 725 S. aureus isolates consecutively collected from non-CF patients with pneumonia from the same medical centers during the same period. Only isolates determined to be the probable cause of pneumonia were included in the study. Susceptibility profiles were very similar among isolates from CF and non-CF patients. Dalbavancin exhibited potent activity (MIC50/90, 0.03/0.03 mg/L) and complete coverage (100.0% susceptibility) against isolates from CF and non-CF patients. Ceftaroline (MIC50/90, 0.25/1 mg/L) was active against 97.8% and 98.1% of isolates from CF and non-CF patients, respectively. Oxacillin resistance (MRSA) rates were 27.7% among CF and 28.7% among non-CF patients. Among MRSA isolates from CF/non-CF patients (n = 99/208), susceptibility to ceftaroline, clindamycin, levofloxacin, and tetracycline were 91.9%/93.3%, 58.6%/64.4%, 40.4%/29.3%, 83.8%/89.4%, respectively. Dalbavancin demonstrated high potency against S. aureus from CF and non-CF patients and may represent a valuable treatment option for CF patients with MRSA pulmonary infection.

PMID:33878463 | DOI:10.1016/j.ijid.2021.04.051