Clinical and Microbiological Outcomes of Serious Infections with Multidrug-Resistant Gram-Negative Organisms Treated with Tigecycline

Abstract

Eighteen patients received tigecycline as treatment for infection due to multidrug-resistant gram-negative bacilli, including Acinetobacter baumannii and Klebsiella pneumoniae carbapenemase- and extended-spectrum beta-lactamase-producing Enterobacteriaceae. Pretherapy minimum inhibitory concentration values for tigecycline predicted clinical success. Observed evolution of resistance during therapy raises concern about routine use of tigecycline in treatment of such infections when other therapies are available.

Detection of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae producing NDM-1 in Lebanon

“…Tigecycline has limited use in urine and primary blood-stream infection despite in vitro susceptibility. In other clinical scenarios, better results were obtained when tigecycline was used in combination [21,22]. Colistin is being reused in the era of antibiotic resistance to treat multidrug resistant strains as either monotherapy or preferably as part of combination therapy [21,23,24].…”

Mutant prevention concentration of tigecycline for carbapenem-susceptible and -resistant Acinetobacter baumannii

“…A new broad-spectrum glycylcycline, tigecycline, shows good in vitro activity against A. baumannii 5,6 and is now considered a good treatment option for multidrug-resistant A. baumannii infections. 7,8 However, tigecycline-resistant A. baumannii has been observed after tigecycline treatment of A. baumannii infections. 7-9 Whether tigecycline is particularly prone to emergence of resistance with A. baumannii is unknown.…”

“…As no interpretive criterion for tigecycline with A. baumannii has been established, Clinical and Laboratory Standards Institute interpretive criteria for Enterobacteriaceae were used for A. baumannii, as had been reported in previous literature (susceptible MIC p2 mg ml -1 ; intermediate MIC, 42 but o8 mg ml -1 ; resistant MIC, X8 mg ml -1 ). 7,8 For determination of the MPC, high-density cultures were prepared from overnight cultures grown in liquid medium followed by a 10-fold dilution and 4 h of incubation with shaking at 37 1C. Then, the suspension was centrifuged (4000 g for 10 min) and re-suspended in fresh Mueller-Hinton broth to yield a concentration of about 10 10 c.f.u.…”

“…Such prediction is consistent with recent reports of emergence of tigecycline-resistant A. baumannii after tigecycline therapy. [7][8][9] Although decreased susceptibility to tigecycline in clinical isolates of A. baumannii is associated with the overexpression of the AdeABC multidrug efflux pump, 19 the proposed mechanism of resistant isolates selected in vitro need further study. Our data suggest that tigecycline may be prone to emergence of resistance with A. Baumannii; thus, close monitoring of A. Baunmanii susceptibilities and patient responsiveness to tigecycline monotherapy is warranted.…”

Clinical and microbiological characterization of KPC-producing Klebsiella pneumoniae infections in Brazil

“…19 In these situations, the use of combined therapy and/or higher doses of tigecycline are critical for maximal therapeutic effectiveness. 20 This would be specially useful in patients with infections due to pathogens with reduced susceptibility to polymyxin, such as those presented in the clinical cases 4 and 6.…”