Here we report tigecycline MICs against truly PDR A. baumannii isolates. Due to the lack of CLSI breakpoints for Acinetobacter, no susceptibility rate could be inferred. It should be noted that our MIC90 (2 g/ml), equal to those in most studies (4), is higher than the achievable concentration of tigecycline in serum at normal dosing (0.63 g/ml) (7). In fact, clinical failures and emergence of resistance have been reported (1, 4, 6). Conversely, tigecycline could provide higher concentration in tissues, implying a theoretical role for tissue-based infections (7). Nevertheless, the only granted use of tigecycline so far is for the treatment of complicated skin/skin structure and intra-abdominal infections caused by bacteria other than Acinetobacter (the U.S. Food and Drug Administration). To date, only the British Society of Antimicrobial Chemotherapy has provided criteria to designate tigecycline-susceptible and -resistant A. baumannii isolates (1 and 2 g/ml, respectively). Implementation of these breakpoints would severely limit the use of tigecycline. However, it could effectively be prescribed as salvage therapy for certain types of infections caused by PDR A. baumannii.