title: Monotherapy versus combination therapy for sepsis due to multidrug-resistant Acinetobacter baumannii: analysis of a multicentre prospective cohort.
abstract: BACKGROUND
  Treatment of multidrug-resistant Acinetobacter baumannii (MDRAB) infection presents a challenge because of the scarcity of available options. Even though combination therapy (CT) is frequently used in clinical practice, data are needed to support its use instead of monotherapy (MT).
  
  
  METHODS
  A prospective observational study was conducted in 28 Spanish hospitals. Patients with sepsis caused by MDRAB, defined according to strict criteria, and who received active antibiotic treatment (according to in vitro susceptibility testing) for at least 48 h, were included. The main outcome variable was all-cause 30 day mortality after initiation of targeted therapy. Multivariate analysis, including a propensity score (for receiving CT), was performed by Cox regression.
  
  
  RESULTS
  One hundred and one patients were included in the analysis; 68 (67.3%) received MT and 33 (32.7%) received CT. Pneumonia was the most common infection (50.5%), 68.6% of cases being associated with mechanical ventilation. Colistin (67.6%) and carbapenems (14.7%) were the most common drugs used in MT; colistin plus tigecycline (27.3%) and carbapenem plus tigecycline (12.1%) were the most frequent combinations. Crude 30 day mortality was 23.5% and 24.2% for the MT and CT groups, respectively (RR = 1.03; 95% CI 0.49-2.16; P = 0.94). Multivariate analysis of 30 day survival showed no trend towards reduced 30 day mortality with CT (HR = 1.35; 95% CI 0.53-3.44; P = 0.53). Subgroup analysis showed similar results.
  
  
  CONCLUSIONS
  Our data do not support an association of CT with reduced mortality in MDRAB infections. More data for specific types of infection and combinations are needed.
authors: Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain luiselopezcortes@gmail.com.
authors: L E
authors: LE
authors: López-Cortés
authors: Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain Instituto de Biomedicina de Sevilla (IBIS), Sevilla, Spain.
authors: J M
authors: JM
authors: Cisneros
authors: Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain.
authors: F
authors: F
authors: Fernández-Cuenca
authors: Servicio de Microbiología, Complejo Hospitalario Universitario A Coruña, La Coruña, Spain.
authors: G
authors: G
authors: Bou
authors: Servicio de Microbiología, Complejo Hospitalario Universitario A Coruña, La Coruña, Spain.
authors: M
authors: M
authors: Tomás
authors: Instituto de Biomedicina de Sevilla (IBIS), Sevilla, Spain Unidad de Medicina Intensiva, Hospital Universitario Virgen del Rocío, Sevilla, Spain.
authors: J
authors: J
authors: Garnacho-Montero
authors: Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain Departamento de Microbiología, Universidad de Sevilla, Sevilla, Spain.
authors: A
authors: A
authors: Pascual
authors: Servicio de Microbiología, Hospital Universitario Marqués de Valdecilla, Santander, Spain Departamento de Biología Molecular, Universidad de Cantabria, Santander, Spain.
authors: L
authors: L
authors: Martínez-Martínez
authors: Barcelona Centre for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Barcelona, Spain.
authors: J
authors: J
authors: Vila
authors: Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain Instituto de Biomedicina de Sevilla (IBIS), Sevilla, Spain Departamento de Medicina, Universidad de Sevilla, Sevilla, Spain.
authors: J
authors: J
authors: Pachón
authors: Unidad Clínica de Enfermedades Infecciosas, Microbiología y Medicina Preventiva, Hospitales Universitarios Virgen Macarena y Virgen del Rocío, Sevilla, Spain Departamento de Medicina, Universidad de Sevilla, Sevilla, Spain.
authors: J
authors: J
authors: Rodríguez Baño
mesh_terms: D000151:Acinetobacter Infections / Q000188:drug therapy* / Q000453:epidemiology; D040981:Acinetobacter baumannii / Q000187:drug effects / Q000302:isolation & purification*; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018805:Sepsis / Q000188:drug therapy* / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents
keywords: A. baumannii; antimicrobial resistance; combination treatment; healthcare-associated infections; nosocomial pneumonia