Clinical Characteristics of Tertiary Hospital Patients from Whom Acinetobacter calcoaceticus-Acinetobacter baumannii Complex Strains were Isolated

Abstract

Objective Acinetobacter baumannii is a worldwide nosocomial pathogen that has become increasingly common over the past few decades, and strains of multidrug-resistant A. baumannii have been increasing. The aim of this study was to assess the clinical characteristics of A. calcoaceticus-A. baumannii complex (Acb complex) strains and to determine the risk factors of this infection. Methods The medical records of 121 patients at Nagasaki University Hospital from whom Acb complex had been isolated between January 2007 and December 2009 were retrospectively reviewed. Patient backgrounds, sensitivity to antibiotics, risk factors for infection, and prognosis were evaluated. Results Lower respiratory isolates accounted for 73% (147 strains) of all 201 isolates. Most of the isolates were sensitive to carbapenems. Of the 121 patients (74 males and 47 females; mean age: 62.1 years), 48 (39.7%) had malignancy and 75 (62.0%) were treated with antibiotics prior to isolation. Thirty-seven of the patients in this study (30.6%) were infected by Acb complex and the most frequent clinical manifestation was pneumonia (18 cases; 48.6%). Approximately 60% of infected patients were treated with β-lactam agent in combination with β-lactamase inhibitors or carbapenems. The mortality rate of infected patients was significantly higher than that of colonized patients (infected: 24.3%, colonized: 6.0%, p<0.05). Risk factors for Acb complex infection include being over 60 years of age, chronic liver disease, and the use of firstgeneration cephalosporins prior to isolation. Conclusion Acb complex was relatively sensitive to antibiotics. The appropriate usage of antibiotics should be continued for the prevention of drug resistance in Acb complex.

Azithromycin Attenuates Lung Inflammation in a Mouse Model of Ventilator-Associated Pneumonia by Multidrug-Resistant Acinetobacter baumannii

“…In general, MDRAB infections tend to occur in immunosuppressed patients (20). In our previous study, the use of immunosuppressive drugs tended to be the factor responsible for poor clinical outcomes after the acquisition of A. baumannii infections (21). Thus, we employed a neutropenic mouse model treated with cyclophospha- group and the AZM-treated (10 or 100 mg/kg) groups were compared.…”

Multidrug resistant and extensively drug resistant Acinetobacter baumannii hospital infection associated with high mortality: A retrospective study in the Pediatric Intensive Care Unit

“…Acinetobacter baumannii is a Gram-negative coccobacillus that has a remarkable ability to acquire antibiotic resistance and that cause persistent nosocomial infections [1] The mortality rate varies from 18.26% to 88.7% depending on the infection source [2,3]. The propensity of Acinetobacter baumannii to be multidrug-resistant (MDR) or extensively drug-resistant (XDR) presents therapeutic challenges [4,5] .…”

Multidrug resistant and extensively drug resistant Acinetobacter baumannii hospital infection associated with high mortality: A retrospective study in the Pediatric Intensive Care Unit

“…The propensity of Acinetobacter baumannii to be multidrug-resistant (MDR) or extensively drug-resistant (XDR) presents therapeutic challenges [4,5] . Invasive operations such as intra trachea mechanical ventilation, inserted invasive devices, intensive care unit stay, recent surgery, use of broad-spectrum antibiotics, ineffective management, and septic shock at diagnosis are reported as risk factors for colonization or infection by MDR Acinetobacter baumannii and higher mortality [6,7] .…”