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Background: Pericardial infection caused by Acinetobacter baumannii is rare, particularly that of carbapenem-resistant A baumannii (CRAB)., Case Presentation: We describe a rare case of purulent pericarditis due to CRAB in a 76-year-old man with acute myocardial infarction and acute kidney injury. The man was admitted to the intensive care unit for a catheter-related bloodstream infection. Pericardial effusion was detected via the bedside X-ray and ultrasound, and pericardiocentesis was performed. Cultures of the pericardial fluid, catheter tip, and blood independently revealed the presence of CRAB. These findings confirmed a diagnosis of purulent pericarditis., Conclusions: Clinicians should be reminded that CRAB infection can lead to purulent pericarditis, particularly in patients with congestive heart failure or renal insufficiency.

Acinetobacter baumannii ( A. baumannii ) strains are common nosocomial pathogens that can cause infections and can easily become resistant to antibiotics. Thus, analytical methods that can be used to rapidly identify A. baumannii from complex samples should be developed. Tail fiber proteins derived from the tail fibers of bacteriophages can recognize specific bacterial surface polysaccharides. For example, recombinant tail proteins, such as TF2 and TF6 derived from the tail fibers of bacteriophages ϕAB2 and ϕAB6, can recognize A. baumannii clinical isolates M3237 and 54149, respectively. Thus, TF2 and TF6 can be used as probes to target specific A. baumannii strains. Generally, TF2 and TF6 are tagged with a hexahistidine (His 6 ) for ease of purification. Given that His 6 possesses specific affinity toward alumina through His 6 -Al chelation, TF2- and TF6-immobilized alumina-coated magnetic nanoparticles (Fe 3 O 4 @Al 2 O 3 MNPs) were generated through chelation under microwave heating (power, 900 W) for 60 s in this study. The as-prepared TF2-Fe 3 O 4 @Al 2 O 3 and TF6-Fe 3 O 4 @Al 2 O 3 MNPs were used as affinity probes to trap trace A. baumannii M3237 and 54149, respectively, from sample solutions. Matrix-assisted laser desorption/ionization mass spectrometry capable of identifying bacteria on the basis of the obtained fingerprint mass spectra of intact bacteria was used as the detection tool. Results demonstrated that the current approach can be used to distinguish A. baumannii M3237 from A. baumannii 54149 by using TF2-Fe 3 O 4 @Al 2 O 3 and TF6-Fe 3 O 4 @Al 2 O 3 MNPs as affinity probes. Furthermore, the limits of detection of the current method for A. baumannii M3237 and 54149 are ∼10 5 and ∼10 4 cells mL -1 , respectively. The feasibility of using the developed method to selectively detect A. baumannii M3237 and 54149 from complex serum samples was demonstrated.

Introduction: The incidence of Acinetobacter baumannii meningitis, which typically occurs after neurosurgery, has increased in recent years. Pediatric Acinetobacter baumannii meningitis due to the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains has important clinical significance., Methodology: We retrospectively reviewed the clinical course and outcome of nine cases of meningitis due to Acinetobacter baumannii in children and reviewed the relevant literature., Results: Seven patients had a history of neurosurgery, and the average time from the first surgery to cerebrospinal fluid (CSF) culture in these seven patients was 23.71 ± 17.43 days. Of all nine patients, four patients showed MDR isolates, two showed XDR isolates, and one showed pan-drug-resistant (PDR) isolates. Three patients received an intrathecal injection of amikacin. Two patients received intravenous colistin (5 mg/kg), and one received polymyxin B (2 mg/kg). The mean hospitalization duration was 39.44 days. Four patients eventually died: two with MDR Acinetobacter, one with PDR Acinetobacter, and one with susceptible Acinetobacter. Two of them still had positive CSF cultures at death., Conclusion: Acinetobacter baumannii meningitis is usually associated with neurosurgery and the placement of foreign material, and it usually has a high mortality. Intrathecal or intraventricular polymyxin administration is expected to be an effective choice for meningitis but requires further study.

Objectives: bloodstream infections (BSI) due to multidrug-resistant (MDR) Acinetobacter baumannii (AB) have been increasingly observed among hospitalized patients., Methods: prospective, observational study conducted among 12 large tertiary-care hospitals, across 7 Italian regions. From June 2017 to June 2018 all consecutive hospitalized patients with bacteremia due to MDR-AB were included and analyzed in the study., Results: During the study period 281 episodes of BSI due to MDR-AB were observed: 98 (34.8%) episodes were classified as primary bacteremias, and 183 (65.2%) as secondary bacteremias; 177 (62.9%) of them were associated with septic shock. Overall, 14-day mortality was observed in 172 (61.2%) patients, while 30-day mortality in 207 (73.6%) patients. On multivariate analysis, previous surgery, continuous renal replacement therapy, inadequate source control of infection, and pneumonia were independently associated with higher risk of septic shock. Instead, septic shock and Charlson Comorbidity Index >3 were associated with 14-day mortality, while adequate source control of infection and combination therapy with survival. Finally, septic shock, previous surgery, and aminoglycoside-containing regimen were associated with 30-day mortality, while colistin-containing regimen with survival., Conclusions: BSI caused by MDR-AB represents a difficult challenge for physicians, considering the high rates of septic shock and mortality associated with this infection., (Copyright © 2019 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

Multidrug-resistant and extensively drug-resistant Acinetobacter baumannii infections have been increasing as a cause of healthcare-associated infections in the neonatal age group. In this report, we describe a 27-week, 1028 g, preterm neonate with extensively drug-resistant A. baumannii infection complicated by ventriculitis who did not respond to intravenous and intraventricular colistin but did respond after intraventricular tigecycline. This is the first case report describing the use of intraventricular tigecycline in a neonate with ventriculitis.

Objective: To develop and validate an interactive nomogram to predict healthcare-associated infections (HCAIs) in the intensive care unit (ICU)., Methods: A multicenter retrospective study was conducted to review 2017 data from six hospitals in Guizhou Province, China. A total of 1,782 ICU inpatients were divided into either a training set (n = 1,189) or a validation set (n = 593). The patients' demographic characteristics, basic clinical features from the previous admission, and their need for bacterial culture during the current admission were extracted from electronic medical records of the hospitals to predict HCAI. Univariate and multivariable analyses were used to identify independent risk factors of HCAI in the training set. The multivariable model's performance was evaluated in both the training set and the validation set, and an interactive nomogram was constructed according to multivariable regression model. Moreover, the interactive nomogram was used to predict the possibility of a patient developing an HCAI based on their prior admission data. Finally, the clinical usefulness of the interactive nomogram was estimated by decision analysis using the entire dataset., Results: The nomogram model included factor development (local economic development levels), length of stay (LOS; days of hospital stay), fever (days of persistent fever), diabetes (history of diabetes), cancer (history of cancer) and culture (the need for bacterial culture). The model showed good calibration and discrimination in the training set [area under the curve (AUC), 0.871; 95% confidence interval (CI), 0.848-0.894] and in the validation set (AUC, 0.862; 95% CI, 0.829-0.895). The decision curve demonstrated the clinical usefulness of our interactive nomogram., Conclusions: The developed interactive nomogram is a simple and practical instrument for quantifying the individual risk of HCAI and promptly identifying high-risk patients., Competing Interests: The authors have declared that no competing interests exist.

Background: Acinetobacter baumannii is a cosmopolitan bacterium that is frequently reported from hospitalized patients, especially those patients who admitted in the intensive care unit. Recently, multiplex real-time PCR has been introduced for rapid detection of the resistance genes in clinical isolates of bacteria. The current study aimed to develop and evaluate multiplex real-time PCR to detect common resistance genes among clinical isolates of A. baumannii., Results: Multiplex real-time PCR based on melting curve analysis showed different T m corresponding to the amplified fragment consisted of 83.5 °C, 93.3 °C and 89.3 °C for blaIMP, blaVIM and blaNDM, respectively. Results of multiplex real-time PCR showed that the prevalence of blaIMP, blaVIM and blaNDM among the clinical isolates of A. baumannii were 5/128(3.9%), 9/128(7.03%) and 0/128(0%), respectively. Multiplex real-time PCR was able to simultaneously identify the resistance genes, while showed 100% concordance with the results of conventional PCR., Conclusions: The current study showed that blaVIM, was the most prevalent MBL gene among the clinical isolates of A. baumannii while no amplification of blaNDM was seen. Multiplex real-time PCR can be sensitive and reliable technique for rapid detection of resistance genes in clinical isolates.

Introduction: Community-acquired (CA) carbapenem-susceptible Acinetobacter baumannii (CSAB) enterogenic sepsis is very rare but has a high mortality. Although CA A. baumannii bloodstream infections have been known to develop from respiratory tract, urinary tract, and intravenous device-related infections, CA A. baumannii bloodstream infections from the gastrointestinal tract have not yet been reported., Patient Concerns: A 73-year-old male with the chief presentation of gastrointestinal symptoms was initially diagnosed with acute gastroenteritis and showed poor clinical response to empirical antibiotic therapy., Diagnoses: The diagnosis of CSAB enterogenic sepsis was established based on results of blood culture, elevated serum procalcitonin level, and specific hemodynamic changes related to septic shock., Interventions: The patient initially received empirical antibiotic treatment (cefodizime 2.0 q12 hours plus moxifloxacin 0.4 qd); then, treatment was changed to the conventional dose of carbapenem (imipenem 0.5 q6 hour)., Outcomes: Finally, CSAB was eliminated from the bloodstream, and the patient was discharged., Lessons: Although severe, CA CSAB enterogenic sepsis is often misdiagnosed because of its clinical rarity. Early diagnosis and appropriate initial empirical antibiotic therapy are crucial for treating such cases.

Background: Carbapenem-resistant Acinetobacter baumannii infections are a major public health problem worldwide, requiring the use of "old" antibiotics such as polymyxin B and E (colistin). However, there is concern regarding the emergence of isolates resistant to these antibiotics., Case Presentation: We report a case of a 64-year-old mestizo man hospitalized in an intensive care unit of a health institution in Colombia with identification and clinical and molecular typing of a colistin- and carbapenem-resistant A. baumannii isolate with mechanisms of resistance to colistin not previously reported, causing bacteremia., Conclusions: We have identified a strain of A. baumannii with mechanisms of resistance to colistin not previously reported in a patient with bacteremia who required treatment with multiple antibiotic schemes and had an adequate response.

Background: Five cases of multi-resistant Acinetobacter baumanii (MRA) producing OXA-23 and OXA-51 occurred in a regional burn intensive care unit (BICU). Three were repatriated from other parts of the world (Dubai and Mumbai) and colonized on admission. Despite optimal precautions, two patients acquired MRA. Both had been nursed in the same room., Methods: Multi-disciplinary outbreak investigation of MRA in a regional BICU., Findings: The mechanism of transfer for the first case is thought to have been contaminated air from theatre activity releasing MRA bacteria into the communal corridor. No MRA patients went to theatre between the first and second acquired cases. The mechanism of transfer for the second case is thought to have been via a shower unit that was decontaminated inadequately between patients., Conclusion: In an outbreak where contact precautions and environmental cleaning are optimal, it is important to give careful consideration to other mechanisms of spread. If there is a failure to do this, it is likely that the true causes of transmission will not be addressed and the problem will recur. It is recommended that burn theatres within burn facilities should be designed to operate at negative pressure; this is the opposite of normal operating theatre ventilation. Where showers are used, both the shower head and the hose should be changed after a patient with a resistant organism. The role of non-contact disinfection (e.g. hydrogen peroxide dispersal) should be reconsidered, and constant vigilance should be given to any 'trojan horse' item in the room., (Copyright © 2018. Published by Elsevier Ltd.)

Bloodstream infection caused by Acinetobacter baumannii has become a major clinical concern, especially multidrug-resistant A baumannii (MDRAB). The aim of this study was to identify the risk factors of nosocomial acquired MDRAB bacteremia and to determine the risk factors related to the mortality of patients with MDRAB bacteremia. Patients with nosocomial acquired A baumannii bacteremia were enrolled between January, 2013 and December, 2017 at the First Affiliated Hospital, School of Medicine, Zhejiang University. Medical records were reviewed, and the clinical and microbial characteristics were collected. Among the 338 patients suffering from A baumannii bacteremia, 274 patients were infected with MDRAB bacteremia. Bacteremia-related mortality was 46.4% for the overall sample; 56.2% for MDRAB bacteremia patients, 4.7% for non-MDRAB bacteremia patients. The identified risk factors for developing MDRAB bacteremia were previous exposure to carbapenems [odds ratio (OR) 5.78, P = .005] and penicillins+β-lactamase inhibitors (OR 4.29, P = .009). Primary bacteremia tended to develop non-MDR bacteremia (OR 0.10, P = .002). The risk factors for MDRAB bacteremia-related mortality were old age (OR 1.02, P = .036), a high Pitt bacteremia score (OR 1.32, P < .001), bacteremia occurring after severe pneumonia (OR 8.66, P < .001), while catheter-related infection (OR 0.47, P = .049) and operations for treating infection (OR 0.51, P = .043) may have a better outcome. Patients with MDRAB had a higher mortality rate. Patients with previous carbapenems and penicillins+β-lactamase inhibitor exposure are at an increased risk of MDRAB bacteremia, whereas patients with primary bacteremia tended to develop non-MDR bacteremia. The risk factors for MDRAB bacteremia-related mortality were old age, a high Pitt bacteremia score, and bacteremia occurring after severe pneumonia, whereas catheter-related infection and operations for the treatment of infection may have a better outcome.

Acinetobacter baumannii is naturally resistant to several classes of antibiotics and readily develops further resistance mechanisms under antibiotic pressure. For patients infected with extremely drug-resistant organisms, effective antibiotic treatments are intravenous and often require inpatient hospitalization for monitoring and dose adjustment. A 31-year-old active duty service member, stationed in Southeast Asia, sustained thermal burns from an electrical arc injury to over 40% of his total body surface area. His hospital course was complicated by multiple extensively drug resistant (XDR) A. baumanii infections including bacteremia and hepatic abscesses. To facilitate discharge to his family, his hepatic abscesses were treated successfully as an outpatient with several weeks of parenteral colistin monotherapy. With regular renal function testing, his dosages were held and/or adjusted to compensate for acute kidney injuries, and he was successfully cleared of his infection. Up to 50% of A. baumannii isolates in American hospitals, including major DOD facilities, are carbapenem resistant. As a result, historically last-line therapies, such as polymyxins, are increasingly used as treatment. New dosing guidance is emphasized to minimize renal toxicities. This case demonstrates the ability to administer parenteral colistin as an outpatient under close supervision., (Published by Oxford University Press on behalf of the Association of Military Surgeons of the United States 2018. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Objectives: Acinetobacter baumannii (Ab) is an important cause of healthcare-associated infections. Multilocus sequence typing (MLST) provides a highly discriminative typing method. We aimed to determine the clinical impact of Ab sequence types (ST) in patients with bloodstream infection (BSI)., Methods: Patients with Ab-BSI were followed prospectively from 2009 to 2014. We randomly selected one-third of non-duplicate bacteremic isolates for MLST and correlated the Ab ST with the clinical course. The primary outcome was all-cause in-hospital mortality., Results: We enrolled 148 patients. Seventy-seven (52.0%) of the isolates were ST2. Patients with ST2-BSI were less likely to be treated with appropriate empirical antimicrobial agents (31.1% vs. 60.6%; P < 0.001). They had greater mortality (66.2% vs. 40.8%; P = 0.003) than patients with non-ST2-BSI. In the multivariable analysis, ST2 independently predicted greater severity of infection (Pitt bacteremia score) (adjusted odds ratio (aOR), 3.38; 95% confidence interval (CI), 1.75-6.54; P < 0.001). Mediated by a higher Pitt bacteremia score (Sobel test P < 0.001), ST2 is an independent prognostic factor that predict mortality (aOR, 2.34; 95% CI, 1.07-5.11; P = 0.03)., Conclusions: ST2 was associated with high rates of inappropriate antimicrobial therapy, severe infection and mortality. Further studies are needed to confirm our findings and explore the potential of role of the virulence., (Copyright © 2018 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

A 62-year-old man with diabetes mellitus and a two-day history of fever and dyspnea presented at our hospital. He was diagnosed with community-acquired pneumonia (CAP), septic shock, and respiratory failure. Sputum Gram staining revealed Gram-negative coccobacilli. Based on the Gram staining findings and history, Acinetobacter baumannii was considered as one of the causative organisms of his CAP. Consequently, he was successfully treated with the initial administration of meropenem. We suggest that A. baumannii should be considered as one of the possible causative organisms of CAP based on a fulminant clinical course, and the presence of Gram-negative coccobacilli.

Introduction: Carbapenem resistance in Acinetobacter baumannii can be mediated by carbapenemases of class A, class B metallo-β-lactamases (MBLs), and class D carbapenem-hydrolyzing oxacillinases (CHDL). The aim of the study was to investigate the antimicrobial susceptibility and β-lactamase production of carbapenem-resistant A. baumannii isolates (CRAB) from the Children's Hospital Zagreb, Croatia., Methods: A total of 12 A. baumannii isolates collected between August 2016 and March 2018 were analyzed. Antibiotic susceptibility was determined by the broth microdilution method. The presence of MBLs was explored by combined disk test with EDTA. The presence of carbapenemases of class A, B, and D was explored by PCR. The occurrence of the ISAba1 upstream of the blaOXA-51-like or blaOXA-23-like was determined by PCR mapping. Epidemiological typing was performed by determination of sequence groups (SG). Genotyping was performed by SG determination, rep-PCR, and MLST., Results: All CRAB were resistant to piperacillin/tazobactam, ceftazidime, cefotaxime, ceftriaxone, cefepime, imipenem, meropenem, gentamicin, and ciprofloxacin. Moderate resistance rates were observed for ampicillin/sulbactam (67%) and tigecycline (42%). The isolates were uniformly susceptible to colistin. PCR revealed the presence of genes encoding OXA-24-like CHDL in nine and OXA-23-like CHDL in three isolates. blaOXA-51 genes were preceded by ISAba1. PCR for the common MBLs in Acinetobacter was negative. All isolates belonged to SG 1 corresponding to ICL (International Clonal Lineage) II. Rep-PCR identified four major clones., Conclusions: The study found OXA-24-like β-lactamase to be the dominant CHDL among children'sCRAB. The predominant spread of OXA-24-like is in contrast with the recent global dissemination of OXA-23 reported all over the world. In contrast to the previous studies in which emergency of OXA-24-like positive isolates was monoclonal, we found considerable genetic diversity of the isolates., (© 2019 S. Karger AG, Basel.)

Aim: To analyse postoperative meningitis (POM) after craniotomy, and to compare the clinical characteristics, treatment outcomes and mortality rates of POM that were caused by Acinetobacter spp. or other possible causes., Material and Methods: In this study, POM cases in our hospital between 2008 and 2016 were retrospectively reviewed. Cases were divided into three groups; Acinetobacter spp. meningitis (case group), non-Acinetobacter bacterial meningitis (control group 1) and culture negative meningitis (control group 2). Demographic, clinical, laboratory features, treatment modalities and mortality rates were compared between case and control groups., Results: A total of 112 patients with POM were included in the study. Cerebrospinal fluid (CSF) culture results were negative in 50 (44.6%) patients; bacteria were isolated from CSF of 62 (55.3%) patients. Acinetobacter spp. was isolated from 28 (45%) patients, while bacteria other than Acinetobacter spp. were detected in 34 (55%) patients. No significant differences were observed between case and control groups in terms of age, gender, comorbidity and operation type. For the case group, change of treatment according to culture result was significantly different from control groups (p < 0.001). Mortality was 55.6% in the case group, 24.2% in control group 1 (p=0.013), and 24% in control group 2 (p=0.006). In multivariate analysis, isolation of Acinetobacter spp. from CSF culture [OR < sub > adj < /sub > 5.2, 95% confidence interval (CI):1.2-22.0, p=0.026] and inappropriate treatment (OR < sub > adj < /sub > 15.7, 95%CI:3.6-68.9, p < 0.001) were determined to be independent risk factors for mortality., Conclusion: Postoperative meningitis, especially caused by Acinetobacter spp., and its inappropriate empirical treatment are associated with high mortality.

In the present study, we developed a phage-based real-time quantitative PCR (qPCR) methodology for sensitive diagnosis of bloodstream infection (BSI) caused by Acinetobacter baumannii (A. baumannii). An isolated A. baumannii phage p53 was used for Taqman qPCR through detecting phage replication in live A. baumannii cells in serum samples. At the phage concentration of 10 3  PFU/mL, the sensitive detection of A. baumannii (down to 10 CFU in 100 μL serum) has been obtained within 4 h in spiked serum samples without bacteria isolation and DNA extraction. Subsequent testing of 22 simulated serum samples spiked by different strains has shown that the results from the phage-based Taqman qPCR method have 100% agreement with the spiked concentrations of the bacteria. The assay built in this study, gathering all the advantages for detections of high rapidity, high sensitivity, good specificity, being able to detect only live bacteria not dead bacteria and no DNA extraction or purifications, can be developed to detecting other bacterial pathogens in serum or other complicated samples through switching to other types of phages and realize the rapid and sensitive detection of bacteria in BSI, which would potentially be applied for fast diagnosis in sepsis clinically., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A set of 204 taxonomically well-defined strains belonging to 17 Acinetobacter spp., including 11 recently described species (A. albensis, A. bohemicus, A. colistiniresistens, A. courvalinii. A. dispersus, A. gandensis, A. modestus, A. proteolyticus, A. seifertii, A. variabilis, and A. vivianii) and six species of the so-called haemolytic clade (A. beijerinckii, A. gyllenbergii, A. haemolyticus, A. junii, A. parvus, and A. venetianus), were subjected to MALDI-TOF mass spectrometric profiling. The identification outputs were evaluated using the current version (8.0.0.0) of the commercially available Bruker Daltonics, Biotyper database, which does not contain reference entries for six of the species tested. Up to 29% of the strains were falsely identified as different Acinetobacter spp. present in the Biotyper database, resulting mostly from the close phylogenetic relationship of species of the haemolytic clade. To obtain more reliable identification, extending the commercial database showed only partial improvement, while the use of an alternative MALDI matrix solution (strongly acidified ferulic acid) allowed correct identification of nearly all problematic strains., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In an era of increasing antimicrobial resistance, Acinetobacter distinguishes itself as one of the most resistant Gram-negative bacteria responsible for significant morbidity and mortality. New solutions are needed to combat the detrimental effects of increasing rates of antimicrobial resistance. Using empiric broad-spectrum antibiotics in patients deemed at risk for infections caused by multidrug-resistant pathogens may protect against attributable mortality, but this temporary solution furthers the risk of antimicrobial resistance. In this article we will review relevant strategies to aid with early identification and appropriate treatment of Acinetobacter pneumonia while preserving antibiotic susceptibility.

Carbapenem-resistant Acinetobacter baumannii (CRAB) infection is a major issues in current era. The aim of study was to investigate the natural prognosis and prognostic factors associated with 28-day mortality in patients with CRAB bacteremia who were not receiving appropriate antibiotic treatment.Adult patients with CRAB bacteremia were retrospectively identified between April 2012 and March 2015 at 5 tertiary hospitals in Republic of Korea. Patients who were transferred to another hospital within 28 days of onset of bacteremia and who receive appropriate antibiotics more than 48 hours were excluded. We investigated prognostic factors associated with 28-day mortality in patients with CRAB bacteremia without appropriate antibiotic treatment.Of enrolled 205 patients, 143 (69.8%) patients died within 28 days after blood culture. Of patients with 28-day mortality, 88.9% (127/143) of patients died within 5 days. Of 78 patients who survived more than 5 days, the 28-day mortality was 20.5% (16/78). Diabetes mellitus (adjusted odds ratio [aOR] 3.81, 95% confidence interval [95% CI] 1.19-12.20), immunocompromised (aOR 8.72, 95% CI 2.62-29.70), sequential organ failure assessment (SOFA) ≥ 10 (aOR 13.87, 95% CI 3.70-51.96), vasopressor use (aOR 7.03, 95% CI 1.79-27.60), and pneumonia (aOR 4.44, 95% CI 1.67-11.78) were found to be the factors independently associated with the 28-day mortality.The 28-day mortality in patients with CRAB bacteremia without appropriate treatment was high, although some patients could survive. Severity and underlying conditions were important prognostic factors in patients with CRAB bacteremia.

Background: Carbapenem resistance in Acinetobacter baumannii in China was mainly mediated by OXA-23-like carbapenemases, while OXA-24/40-like carbapenemases were rarely identified. OXA-72 is one variant of OXA-24/40-like carbapenemases. This study aimed to demonstrate the epidemiology and characterizations of OXA-72-producing A. baumannii in a Chinese hospital., Methods: A total of 107 clinical A. calcoaceticus-A. baumannii (Acb) complex isolates were collected in a Chinese hospital during between 2014 and 2016. These isolates were identified using Vitek 2 system and gyrB multiplex PCR. Vitek 2 system was used for antibiotic susceptibility testing. Genes encoding for major classes of carbapenemases were investigated by PCR. Rep-PCR was used for genotyping of all the A. baumannii isolates. The risk factors for carriage of OXA-72-producing or OXA-23-producing A. baumannii were analyzed through univariate and multivariate logistic regression., Results: Of the 107 Acb isolates collected, 101 isolates (94.4%) and 6 isolates (5.6%) were identified as A. baumannii and A. pittii, respectively. 78 A. baumannii isolates (77.2%) were carbapenem resistant and mainly cultured from intensive care unit (ICU). bla OXA-72 and bla OXA-23 genes were identified in 45(57.7%) and 33(42.3%) carbapenem-resistant A. baumannii (CRAB), respectively. Multivariate risk factor analyses showed that prior carbapenem usage and nasogastric intubation were significantly associated with carriage of OXA-72-producing A. baumannii or OXA-23-producing A. baumannii. Rep-PCR analysis showed that 9 and 22 Rep-PCR types were assigned to 78 CRAB isolates and 23 carbapenem-susceptible A. baumannii (CSAB) isolates, respectively. A higher diverstiy of Rep-PCR patterns was observed among OXA-72-producing A. baumannii isolates than OXA-23-producing A. baumannii isolates, but all of them belonged to the same clone complex. MLST analysis suggested that the OXA-72 isolates from this study correspond to CC92/CC2 clone complex., Conclusions: This study demonstrates high prevalence and potential clonal spread of closely related genotypes of OXA-72-producing A. baumannii within a Chinese hospital. Continuous surveillance is necessary to monitor the dissemination of these strains in other healthcare settings to guide infection control policies in order to curb the spread of this bacterium.

Background : Acinetobacter baumannii is a health burden responsible for various nosocomial infections, and bacteremia in particular. The resistance of A. baumannii to most antibiotics including carbapenem has increased. OXA-23-producing A. baumannii is the chief source of nosocomial outbreaks with carbapenem-resistant A. baumannii Successful antibiotic treatment relies on the accurate and rapid identification of infectious agents and drug resistance. Here, we describe a multiplex loop-mediated isothermal amplification (LAMP) assay for simultaneous and homogeneous identification for A. baumannii infection screening and drug-resistance gene detection. Methods : Four primer pairs were designed to amplify fragments of the recA gene of A. baumannii and the oxa-23 gene. The reaction with a 25 μl of final volume was performed at 63°C for 60 min. For comparative purposes, we used a traditional method of bacterial identification to evaluate assay efficacy. Results : The multiplex LAMP assay enables simultaneous and homogeneous detection of the recA gene of A. baumannii and the oxa-23 gene and requires less than 21 min with no pre-requisite for DNA purification prior to the amplification reaction. The detection is specific to A. baumannii , and the coincidence rate of the multiplex LAMP and the traditional method was 100%. Conclusions : Our data indicate that the multiplex LAMP assay is a rapid, sensitive, simultaneous and homogeneous method for screening of A. baumannii and its drug-resistance gene., (© 2018 The Author(s).)

Purpose: This study aimed to characterize A. baumannii strains isolated from patients in an intensive care unit (ICU) setting. Molecular techniques were used to study clonal relatedness and determine a fast, efficient and cost-effective way of detecting persistent clones., Methodology: A. baumannii (n=17) were obtained in June and November 2015 from a single ICU setting in South India. DNA typing methods such as multilocus sequence typing (MLST), single-locus sequence-based typing (SBT) and DNA fingerprinting PCRs (M13, DAF4 and ERIC2) were employed to understand the association of clones. PCRs were performed for the antimicrobial resistance genes ISAba1-blaOXA-51-like, ISAba1-blaOXA-23-like, blaNDM-1, blaPER-7 and blaTEM-1, and the virulence genes cpa 1, cpa2 and pkf., Results: The MLST showed some degree of corroboration with the other DNA typing methods. The M13 PCR was found to give better results than the other fingerprinting methods. ST848 (CC92) was the dominant strain isolated in both June and November. All isolates were blaOXA-51-like-positive, with 16 having ISAba1 upstream of the blaOXA-51-like and blaOXA-23-like genes. Genes such as blaNDM-1 (23 %, n=4), blaPER-7 (58.8 %, n=10), pkf (82 %, n=14), blaTEM-1 (5.8 %, n=1), cpa1 (5.8 %, n=1) and cpa2 (5.8 %, n=1) were also detected., Conclusion: M13 PCR can be used in routine environmental surveillance for the detection of persistent antibiotic resistant clones in an ICU setting because of its reliability and simplicity. Further studies based on greater sample size, conducted at the multi-centre level, can give us a better understanding of the reliability of the molecular methods that can be used for the detection of persistent clones in the hospital setting.

Automated systems Vitek 2, BD Phoenix, MicroScan WalkAway and gradient diffusion assays Etest and MIC Test Strip were compared against broth microdilution for susceptibility testing of tigecycline against Acinetobacter baumannii. BD Phoenix and MIC Test Strip seemed to provide the most accurate determination of tigecycline susceptibility., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objectives: This study aimed to investigate antibiotic prescribing patterns and effectiveness of different anti-carbapenem-resistant Acinetobacter baumannii (CRAB) strategies for CRAB pneumonia., Methods: We conducted a multicentre, retrospective study in three hospitals. During 2010-2015, adult ICU patients with CRAB pneumonia treated with at least one antimicrobial agent covering the CRAB isolate in vitro for more than 2 days were included. We used multivariate logistic regression to analyse the associations of anti-CRAB strategies with ICU mortality and other clinical outcomes., Results: Among 238 patients with CRAB pneumonia, tigecycline monotherapy (84, 35.3%) was the most common antibiotic strategy, followed by tigecycline with colistin (43, 18.1%), colistin monotherapy (34, 14.3%), colistin combination without tigecycline (33, 13.9%), tigecycline combination without colistin (32, 13.4%), and sulbactam-based therapy without tigecycline and colistin (12, 5.0%). In multivariate analysis, tigecycline-based therapy was associated with higher ICU mortality than non-tigecycline therapy (adjusted OR 2.30, 95% CI 1.19-4.46). There was no difference between colistin-based therapy and non-colistin therapy. Compared with tigecycline monotherapy, colistin monotherapy was associated with lower ICU mortality (aOR 0.30, 95% CI 0.10-0.88). Treatment failure analyses showed similar trends. Tigecycline-based therapy was associated with higher treatment failure rate than non-tigecycline therapy (aOR 2.51, 95% CI 1.39-4.54), whereas colistin-based therapy was associated with lower treatment failure rate than non-colistin-based therapy (aOR 0.48, 95% CI 0.27-0.86)., Conclusions: Tigecycline was commonly prescribed for CRAB pneumonia. However, tigecycline-based therapy was associated with higher ICU mortality and treatment failure. Our study suggests that colistin monotherapy may be a better antibiotic strategy for CRAB pneumonia., (Copyright © 2017 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: The healthcare environment is a potential source of microbial pathogens, which may promote infectious cross-transmission. Terminal automated cleaning methods such as hydrogen peroxide systems have proven to be more successful than manual techniques. The aim of this study was to evaluate the effectiveness of an automated aerosolized hydrogen peroxide/silver cations dry-mist system. The goal was to prevent microbial transmission to patients in a clinical setting after two cases of sepsis caused by multi-drug resistant Acinetobacter baumannii had been diagnosed in a burn unit that relied on manual cleaning techniques., Materials and Methods: Samples were taken from room surfaces before and after the dry-mist system cycle, which was used to disinfect all burn unit rooms after patient discharge. The disinfection effectiveness was assessed using contact plate cultures, with microbial growth represented as the total number of colony forming units per square centimeter (CFUs/cm 2 )., Results: No positive cultures from surface samples were observed after the intervention with the dry-mist system. Specifically, no further Acinetobacter baumannii growth was detected., Conclusions: Our results support the use of the hydrogen peroxide/silver cations dry-mist system as an adjunct to standard manual cleaning and disinfection protocols used in the healthcare environment because of its broad-spectrum and high antimicrobial activity. This system may be a valuable option to consider, particularly in the control of microbial outbreaks.

Background: Acinetobacter is a rare but important cause of peritonitis in peritoneal dialysis (PD) patients. As the complication has not been comprehensively evaluated previously, the present study examined the outcomes of Acinetobacter peritonitis in a large, national cohort of PD patients., Methods: The study included all episodes of peritonitis in Australia from January 2004 to December 2014 using Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) data. The primary outcome was peritonitis cure and secondary outcomes were catheter removal, hemodialysis transfer, recurrent/relapsing peritonitis, peritonitis-related hospitalization, and death. Outcomes were compared using multivariable logistic regression., Results: Overall, 5,367 patients experienced 11,122 episodes of peritonitis across 51 centers in Australia. Of these, 228 (4.2%) patients experienced 253 (2.3%) episodes of Acinetobacter peritonitis (176 episodes were due to Acinetobacter alone and 77 involved co-infection with other organisms). Of the 176 solitary Acinetobacter episodes, 131(74%) achieved cure with antibiotics alone. Compared with Acinetobacter , significantly lower odds of peritonitis cure were observed for Pseudomonas (adjusted odds ratio [AOR] 0.24, 95% confidence interval [CI]: 0.16 - 0.36), other gram-negative organisms (AOR 0.54, 95% CI 0.37 - 0.77), fungi (AOR 0.02, 95% CI 0.01 - 0.03), and polymicrobial organisms (AOR 0.36, 95% CI 0.25 - 0.51), whilst similar odds of cure were observed for Staphylococcus (AOR 0.73, 95% CI 0.50 - 1.06), other gram-positive organisms (AOR 1.32,95% CI 0.93 - 1.89), culture-negative (AOR 1.19, 95% CI 0.82 -1.71), and other organisms (AOR 0.72, 95% CI 0.49 - 1.07). The odds of catheter removal and hemodialysis transfer were higher with Pseudomonas , other gram-negative, fungal, and polymicrobial peritonitis than with Acinetobacter peritonitis. The odds of death were also higher with Pseudomonas and fungal peritonitis than with Acinetobacter peritonitis. Treatment of Acinetobacter peritonitis with gentamicin, ciprofloxacin, or ceftazidime achieved comparable outcomes., Conclusions: Outcomes of Acinetobacter peritonitis were favorable compared with most other forms of organism-specific peritonitis. Commonly used antibiotics covering gram-negative bacteria achieved comparable outcomes in Acinetobacter peritonitis., (Copyright © 2018 International Society for Peritoneal Dialysis.)

Background: Acinetobacter species can exhibit widespread resistance to antimicrobial agents. They are already recognized as important nosocomial pathogens of humans, but are becoming increasingly recognized in opportunistic infections of animals., Hypothesis/objectives: This study aimed to determine whether Acinetobacter spp. are carried on skin of healthy dogs and, if present, to identify the species., Animals: Forty dogs were sampled at veterinary practices and rescue centres. They were free from skin disease and receiving no systemic or topical treatments., Methods: Skin swab samples were collected from four sites on each dog and cultured. Acinetobacter spp. isolates were detected by biochemical tests and gas chromatography. The species was determined by sequencing the RNA polymerase β-subunit (rpoB) gene. Isolates were screened for OXA carbapenemase genes and class 1 integrons capable of carrying resistance genes, and subjected to antimicrobial susceptibility tests., Results: For 25% dogs sampled (10 of 40), Acinetobacter spp. were isolated at one or more skin sites. Thirteen Acinetobacter spp. isolates were recovered from 160 samples. The most frequently cultured was A. lwoffii (seven of 13), followed by A. baumannii (two of 13), A. junii (one of 13), A. calcoaceticus (one of 13), A. pittii (one of 13) and a novel Acinetobacter species (one of 13). Class 1 integrons and bla OXA -23-like were not detected. Isolates were susceptible to most antibiotics., Conclusions and Clinical Importance: The study confirms that Acinetobacter spp. can survive on canine skin, where they may be potential reservoirs for infection. This highlights the importance of good hygiene in veterinary practice, adhering to aseptic principles in surgery, and treatment based on culture and susceptibility testing where possible., (© 2018 ESVD and ACVD.)

Identifying the trends in community-onset Acinetobacter baumannii complex isolation and diversity according to temperature could help provide insight into the behavior of the A. baumannii complex. We performed a retrospective analysis of A. baumannii complex (Acinetobacter baumannii, Acinetobacter nosocomialis, Acinetobacter pittii, and Acinetobacter calcoaceticus) isolates obtained from patients at a Korean community hospital from 2006 to 2015 with reference to seasonal temperatures. The incidence rates were compared between warm (June-September) and cold (November-March) months, defined as an average mean temperature ≥20°C and ≤5°C, respectively. Incidence rate was calculated as the number of cases per month, converted to cases/10⁵ admissions for healthcare-acquired isolates and cases/10³ outpatients for community-onset isolates. Approximately 3,500 A. baumannii complex cases were identified, and 26.2% of them were community-onset cases. The median (interquartile range) number of community-onset A. baumannii complex cases was significantly higher (P=0.0002) in warm months at 13.8 (9.5-17.6) than in cold months at 10.1 (6.3-13.2). There was a strong correlation between community-onset A. baumannii complex cases and temperature (Pearson's r=0.6805, P=0.0149). Thus, we identified a seasonality pattern for community-onset A. baumannii complex colonization or infection, but not for healthcare-acquired cases., Competing Interests: The authors of this study have no potential conflicts of interest relevant to this article to disclose., (© The Korean Society for Laboratory Medicine.)

Background: Acinetobacter baumannii is ubiquitous, facultative intracellular, and opportunistic bacterial pathogen. Its unique abilities allow it to survive in a diverse range of environments, including health care settings, leading to nosocomial infections. And its exceptional ability to develop resistance to multiple antibiotics leaves few drug options for treatment. It has been recognized as a leading cause of nosocomial pneumonia and bacteremia over the world., Case Presentation: In this case, a 73-year-old woman presented with a Neer Group VI proximal humeral fracture. Six hours after a successfully performed hemiarthroplasty, she developed continuous fever. Clinical examination revealed that the vitals were regular. Laboratory and radiographic examinations revealed only elevated procalcitonin levels. Blood culture revealed no bacterial or fungal growth. Cooling treatment and empirical broad-spectrum antibiotic therapy showed no apparent effect., Conclusions: We report a postoperative infection caused by Acinetobacter baumannii. The infectious pathogen was identified via molecular DNA sequencing and was initially misidentified as a free-living amoeba species upon microscopic examinations. The patient was mistreated with antiamebic combination therapy. Her symptoms persisted for over 4 months and were eventually followed by her death.

Background: The impact of multidrug-resistant organisms (MDROs), including non-fermentative bacilli (NFBs), is rising and underestimated, especially in intensive care units (ICUs). The growing prevalence of multidrug resistance (MDR) and extensive drug resistance (XDR) is challenging for clinicians, as the treatment options are limited., Objectives: The purpose of this study was to analyze the extent of the epidemiological problem of multidrugresistant, extensively drug-resistant and pandrug-resistant (PDR) non-fermentative bacilli isolated from pneumonia and bloodstream infections (BSIs) in patients hospitalized in southern Poland., Material and Methods: This study included 253 NFBs belonging to Acinetobacter sp. (ACI), Pseudomonas sp. (PAR), and Stenotrophomonas sp. (STM). The microorganisms were identified, and susceptibility testing was performed using a semi-automatic system. The different patterns of resistance were defined as MDR, XDR, or PDR strains. Epidemiological typing of A. baumannii from ICUs was performed by repetitive polymerase chain reaction (rep-PCR)., Results: More than half of the strains (57.7%) were isolated within ICUs. ACI-strains came significantly more often from ICU wards. The highest prevalence of ACI and PAR was found in pneumonia, whereas STM dominated in BSIs. ACIs were more frequently resistant than other pathogens to all studied antibiotics except colistin (n = 76; 58.9%), and they belonged to the XDR category. DiversiLab demonstrated the presence of 2 dominant clones in the ACI group, both classified as European Clone 2 (EUII)., Conclusions: Our results indicate serious potential therapeutic problems related to high antibiotic resistance of ACI isolates. The stratification of drug resistance (MDR/XDR/PDR) may become an important tool for the assessment of public health epidemiology and microbiological hazards at the local, national, and international level. It allows clear presentation of the issues concerning the epidemiology of highly resistant bacilli, and the exchange of information between medical staff and local representatives of public health for the implementation of effective measures to reduce drug resistance.

Omp34, also known as Omp34kDa or Omp33-36 is a virulence factor associated with A. baumannii metabolic fitness or its adherence and invasion to human epithelial cells. This protein is also introduced as a specific antigen which could induce strong antibody responses. In the present in silico study, recent vaccine design strategies such as 'antigen minimization' and 'high epitope density' were invoked to design a soluble immunogen with higher antigenicity. As an advantage, the tools employed in the current study are easily available. Exposed peptides in linear B-cell epitopes were predicted and their conservancy and immunogenicity were evaluated. In this regard, constructs were designed by removal of inappropriate regions. Based on the obtained results the external loops (L1-L7) were exclusively considered of which L3, L6 and L7 were the most appropriate of which the most appropriate were in L3>L6>L7 order while L2 was assigned as an inappropriate peptide. The final construct, named Omp34-4, encompasses three copies of L3, two copies of L6 and L7 and one copy of L1, L4 and L5. The designed construct is predicted to be a soluble antigen with enhanced epitope density and antigenicity. Omp34 is present in >1600 strains of A. baumannii with ≥98% identity. So, it could be applicable in diagnostic kits and an immunotherapy choice against A. baumannii. It could be presumed that co-administration of Omp34-4 and a recently designed OmpA-derived antigen could confer sufficient protection against A. baumannii-associated infections. In vitro and in vivo experiments are needed to confirm all these data. The innovative approach could be generalized to vaccine designs focused on OMPs., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Aim: To present the microbiological details and clinical outcomes of Acinetobacter spp. endophthalmitis with the first reported case of A. haemolyticus., Methods: A retrospective study of microbiologically proven Acinetobacter spp. endophthalmitis was carried out from 2010 to 2015. The data collected included age, type of endophthalmitis, best-corrected visual acuity (BCVA), species involved, and antibiotic susceptibility pattern. The primary outcomes measured were anatomical outcomes in terms of globe integrity and functional outcome as BCVA at last follow-up., Results: Eleven patients out of 3004 patients who underwent surgery for endophthalmitis were due to Acinetobacter spp. Seven cases (63.6%) were both smear and culture positive; there were two cases (18%) each of A. haemolyticus and A. baumanii. Four cases (36%) were only culture positive with negative smear. Three cases (27.2%) were polymicrobial. Ten cases (91%) were susceptible to amikacin and nine (82%) to ciprofloxacin. Six (54.5%) were resistant to ceftazidime. Mean logMAR BCVA improved to 1.8 (20/1330) from an initial 2.5 (20/6839). Pthisis bulbi was seen in two cases (18%)., Conclusions: Even though the outcomes of Acinetobacter spp. endophthalmitis are modest to poor, outcomes following intervention are relatively good for A. haemolyticus. These cases have good susceptibility to amikacin, but are often resistant to ceftazidime.

Bacterial meningitis is a medical emergency needing quick and timely diagnosis. Even though meningitis caused by Acinetobacter baumannii is relatively rare, it is associated with high mortality rates especially in neurosurgery patients and represents a serious therapeutic problem due to the limited penetration of effective antibiotics into the cerebrospinal fluid. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF) has been effectively used as a rapid method for microbial identification. In this case report we identified A. baumanni by MALDI-TOF technique directly from the CSF drawn from the external ventricular drainage of a patient with severe confusional state and signs of meningism. Simultaneously the antibiotic susceptibility test was performed by automated method from the pellet of the broth-enriched sample. The MALDI-TOF technique allowed microbial identification in less than 30 minutes, and the susceptibility test result was available in eight hours, thus allowing a fast diagnosis ready for prompt and targeted antimicrobial therapy.

Acinetobacter baumannii (A. baumannii) is widely known as an opportunistic bacterial pathogen that causes infection more frequently among immunocompromised individuals. Our case demonstrated the limitation of the current VITEK 2 system for the idendification of A. baumannii. Four clinical isolates of A. baumannii were identified as Alcaligenes faecalis by the VITEK 2 system. Misidentification might lead to unnecessary tests and inappropriate treatments. Additional methods appear to be helpful for the accurate identification of A. baumannii for clinical microbiology laboratories., (© American Society for Clinical Pathology 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objectives: Acinetobacter baumannii is considered an important nosocomial pathogen worldwide owing to its increasing antibiotic resistance. This study aimed to determine the complete genome sequence of A. baumannii strain A1296 and to perform a comparative analysis among A. baumannii., Methods: The complete genome sequence of A. baumannii A1296 was sequenced on two SMRT cells using P6C4 chemistry on a PacBio Single Molecule, Real-Time (SMRT) RS II instrument. The A1296 genome sequence was annotated using Prokaryotic Genome Automatic Annotation Pipeline (PGAAP), and the sequence type and resistance genes of the strain were analysed., Results: Here we present the complete genome sequence of A. baumannii strain A1296, belonging to a novel sequence type (ST1469) and isolated from patient in China, that was sensitive to multiple antibiotics. The genome of A. baumannii A1296 was 3810701bp in length, including one circular chromosome and two plasmids. The tet(39) resistance gene was located on the small plasmid in this A. baumannii strain., Conclusions: The genome sequence of A. baumannii strain A1296 can be used as a reference sequence for comparative analysis aimed at elucidating the acquisition, dissemination and mobilisation of resistance genes among A. baumannii., (Copyright © 2017 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

We aimed to establish the role of MALDI-TOF MS on species discrimination of phenotypically indistinguishable A. baumannii, A. pittii and A. nosocomialis. Compared to multiplex PCR, the gold standard, MALDI-TOF MS yielded a high sensitivity for A. baumannii (97.9%) and specificity for A. pittii (98.9%) and A. nosocomialis (100%)., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In recent years, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has become the standard for routine bacterial species identification due to its rapidity and low costs for consumables compared to those of traditional DNA-based methods. However, it has been observed that strains of some bacterial species, such as Acinetobacter baumannii strains, cannot be reliably identified using mass spectrometry (MS). Raman spectroscopy is a rapid technique, as fast as MALDI-TOF, and has been shown to accurately identify bacterial strains and species. In this study, we compared hierarchical clustering results for MS, genomic, and antimicrobial susceptibility test data to hierarchical clustering results from Raman spectroscopic data for 31 A. baumannii clinical isolates labeled according to their pulsed-field gel electrophoresis data for strain differentiation. In addition to performing hierarchical cluster analysis (HCA), multiple chemometric methods of analysis, including principal-component analysis (PCA) and partial least-squares discriminant analysis (PLSDA), were performed on the MS and Raman spectral data, along with a variety of spectral preprocessing techniques for best discriminative results. Finally, simple HCA algorithms were performed on all of the data sets to explore the relationships between, and natural groupings of, the strains and to compare results for the four data sets. To obtain numerical comparison values of the clustering results, the external cluster evaluation criteria of the Rand index of the HCA dendrograms were calculated. With a Rand index value of 0.88, Raman spectroscopy outperformed the other techniques, including MS (with a Rand index value of 0.58)., (Copyright © 2017 Ghebremedhin et al.)

Acinetobacter species are not considered skin commensals and under-treatment is an overriding concern when caring for critically-ill patients who are mostly at risk of extensively drug-resistant Acinetobacter baumannii (XDRAB) infections. Hence even a single blood culture yielding XDRAB will tend to prompt intervention. However, field observations suggest that patients with single-positive blood cultures had milder disease and were more likely to be recruited in interventional studies than those with multiple-positive blood cultures, yet no distinction is made in current clinical or trial recruitment practices. To our knowledge, this is the first study to compare the clinical characteristics and outcomes of patients with single-positive versus multiple-positive blood cultures for XDRAB. In this multicenter prospective cohort study of XDRAB bacteremic patients from July 2010 to June 2015, only patients with at least two simultaneously drawn blood cultures were included. The patients were classified as having single-positive or multiple-positive blood cultures according to the number of positive blood cultures yielding XDRAB. The primary end-point was the 28-day mortality. Of a total of 155 patients enrolled, 69 had a single-positive and 86 had multiple-positive blood cultures. Leukopenia (37.2% vs. 16.2%; P = 0.004), thrombocytopenia (56.0% vs. 26.5%; P < 0.001), higher Pitt bacteremia scores (6.6 vs. 5.5, P = 0.03) and higher 28-day mortality rates (70.9% vs. 43.5%; P = 0.001) distinguished patients with multiple-positive from those with single-positive cultures. Multivariate logistic regression showed that multi-positivity independently predicted 28-day mortality (adjusted odds ratio, 2.34; 95% confidence interval (CI), 1.03-5.28; P = 0.04) and the Cox regression confirmed that multi-positivity (adjusted hazard ratio, 1.80; 95% CI, 1.13-2.85; P = 0.01) predicted rapid mortality. Patients with multiple versus single positive blood cultures yielding XDRAB had greater morbidity and mortality. Investigators and clinicians should be aware that the blood culture positivity rate impacts outcomes of XDRAB bacteremia.

Objective: Infections due to multidrug- and extensively drug-resistant forms of Acinetobacter baumannii (MDR-AB and XDR-AB, respectively) have become increasingly prevalent. This retrospective study compared the outcomes of patients infected with MDR-AB or XDR-AB and treated with one of three antibiotics., Methods: Enrolled were patients with MDR-AB or XDR-AB pulmonary infection based on their first sputum culture. Patients were treated empirically with carbapenems (n = 46), tigecycline (n = 25), or cefoperazone/sulbactam (cefina-SB; n = 35). The therapeutic efficacies of the drugs and patient outcomes were retrospectively compared. Bacterial resistance to the three antibacterials was determined based on sputum cultures from all enrolled patients., Results: The study included 106 patients. After 7 days of treatment, the favorable response rates to tigecycline (60%) and to cefina-SB (71.4%) were statistically similar (p = 0.355) but significantly higher than that to carbapenems (23.9%; p = 0.003 and p < 0.001, respectively). Sputum culture analyses to determine antibiotic susceptibility indicated that 10.4% of patients' sputum cultures were susceptible to carbapenems, 76.4% to tigecycline, and 66.0% to cefina-SB. In addition, 58.5% were susceptible to both tigecycline and cefina-SB., Conclusions: Tigecycline and cefina-SB appeared to be more effective against MDR-AB and XDR-AB pulmonary infections than carbapenems, especially for patients who had been admitted to the intensive care unit multiple times.
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Early detection of Acinetobacter baumannii, an emerging pathogen in hospital settings, is of interest. The bla OXA-51-like family had been used as a marker to detect A. baumannii. During an infection outbreak, 14 isolates produced a 1.7-kb PCR band instead of 353 bp for this marker. This work sought the reasons behind the increased marker size. Characterisation of isolates was done by API-20NE, gyrB multiplex PCR and 16S-23S rRNA ITS sequencing. The 1.7-kb band generated and the complete bla OXA-51-like variant were sequenced to find the probable integrated element. Susceptibility testing to various antimicrobials was performed by microdilution. bla OXA-like , metallo-β-lactamases (MBLs), the ISAba1 element and the presence of ISAba1 adjacent to bla OXA-like were sought. rep-PCR, global clonal (GC) lineage determination and multilocus sequence typing (MLST) were performed to analyse the relationship among isolates. Isolates were characterised as Acinetobacter baumannii-calcoaceticus complex by API-20NE. gyrB multiplex PCR and 16S-23S ITS sequencing verified the isolates as A. baumannii. Sequencing of the 1.7-kb band revealed ISAba19 as the disrupting element. The bla OXA-51 variant was bla OXA-66 , which was elongated to 2.2 kb due to ISAba19. The bla OXA-23-like family was found in 67% of isolates. MBL genes were not detected; however, ISAba1-bla OXA-23-like was characterised in carbapenem-resistant isolates (53%; 8/15). Isolates were divided into three clusters by rep-PCR. All strains were ST2 and all but one belonged to GC II. Identification of A. baumannii based only on bla OXA-51-like is not reliable. Besides bla OXA-51-like , multiplex PCR of gyrB and rpoB could provide rapid and cost-effective results., (Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.)

The increase in carbapenem-resistant gram-negative bacteria is a matter of concern due to the limited therapeutic options available. In severe infections caused by these isolates, the rapid detection of the mechanisms of resistance is vital. We described a slightly modified version of the Blue-Carba test, rapid Blue-Carba test, which allows the detection of carbapenemases at 4 h of incubation from a haze of bacterial growth obtained from a positive blood culture. It was able to detect carbapenemase-producing isolates (Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii) with a sensitivity and specificity of 98.1 and 100%, respectively. It is a rapid, easy-to-perform and an inexpensive technique that can be applied to routine laboratories, together with the simultaneous identification by mass spectrometry which would help to screen non-enzymatic carbapenem resistance; this method allows the detection of clinically relevant multidrug-resistant bacteria and the early implementation of accurate therapeutic interventions.