Tigecycline treatment of critically ill patients: the LatinUser experience

Tigecycline is the first of a new class of antibiotics named glycylcyclines and it was approved for the treatment of complicated intra-abdominal infections and skin and skin structure infections and community-acquired bacterial pneumonia. Notwithstanding this, the tigecycline's pharmacological and microbiological profile encourage physicians' use of the drug in other infections. The aim of this study was to characterize the indications type, pathogens, and outcomes of patients who were treated with tigecycline. We analyzed the tigecycline prescriptions in 209 patients in 23 Latin American centres using an electronic form included in the website LatinUser (http://www.clinicalrec.com.ar). Sixty-six patients (31.5%) received tigecycline for approved indications, and 143 (68.5%) for "off label" indications (47% with scientific support and 21.5% with limited or without any scientific support). The most frequent "off label" use was ventilator-associated pneumonia (VAP) (76 patients). The etiology of infections was established in 88 patients (42%). Acinetobacter spp. (54.5%, in 65% of cases carbapenems-resistant), methicillin-resistant Staphylococcus aureus (12%), and extended spectrum β-lactamases-producing Enterobacteriaceae (10%) were the most common microorganisms isolated. Overall, attending physicians reported clinical success in 144 of the 209 patients (69%). Global mortality proportion was 35,5% (74/209 patients). Our study shows that the off label use of tigecycline is frequent, especially in VAP due to multidrug-resistant pathogens, where the therapeutic options are limited (eg: carbapenems-resistant Acinetobacter spp.). Physicians must evaluate the benefits/risks to use this antibiotic for indications that lack rigorous scientific support.