Acinetobacter baumannii Also Acinetobacter baumannii is increasingly reported as the cause of nosocomial infections. Acinetobacter isolates demonstrate increasing resistance
to commonly prescribed antimicrobials. Selleck BVD-523 Multidrug-resistant Acinetobacter baumannii is one of the most difficult healthcare-associated infections to control and treat [179–181]. The management of A. baumannii infections is difficult, because of the increasing number of isolates exhibiting resistance to multiple classes of antibacterial agents [182, 183]. Agents potentially effective against A. baumannii include carbapenems, XAV939 aminoglycosides (amikacin or gentamicin), tetracyclines (minocycline or doxycycline) and sulbactam . Data from TEST (The Tigecycline Evaluation and Surveillance Trial) during 2004-2007 showed that the most active agents against Acinetobacter spp. were tigecycline, minocycline and Group 2 carbapenems . Resistance to tigecycline and carbapenems makes multidrug-resistant Acinetobacter infections difficult to treat. Colistin and polymyxin B have been used to treat highly resistant Acinetobacter infections. The choice of appropriate therapy is further complicated by the toxicity of colistin Sepantronium ic50 [186, 187]. Acinetobacter isolates resistant to colistin and polymyxin B have also been reported
. Studies have demonstrated in-vitro susceptibility of multidrug-resistant Acinetobacter to various synergistic
combinations of antimicrobials including carbapenems, colistin, rifampin, ampicillin-sulbactam and tigecycline [189, 190]. Bacteroides fragilis The Bacteroides fragilis group much is a predominant component of the normal bacterial flora of the gastrointestinal tract. These bacteria are frequently isolated from mixed aerobic-anaerobic infections, such as intra-abdominal infections. The increasing resistance to antimicrobial agents among anaerobic pathogens has been a global problem in the last years. Susceptibility to antibiotics varies considerably among the species of the group. Clinically, Bacteroides species have exhibited increasing resistance to many antibiotics. Resistance to the most active drugs, such as imipenem, piperacillin-tazobactam, and metronidazole, has been found in occasional strains [191, 192]. Most clinical laboratories do not routinely determine the species of the organism or test the susceptibilities of any anaerobic isolates, including those in the B. fragilis group, because of technical difficulties surrounding Bacteroides susceptibility testing. Consequently, the treatment of anaerobic infections is selected empirically, based on published reports on patterns of susceptibility . A multicenter study by Aldridge et al.