Multidrug-resistant Acinetobacter Spp Research Articles

The Characteristics and Outcome of Patients with Traumatic Brain Injury in the Intensive Care Unit of a Public Sector Hospital in Karachi, Pakistan

Objective: To determine the characteristics, management and outcome of patients with traumatic brain injury (TBI) and associated risk factors.Methods: This cross-sectional study was conducted at Shaheed Mohtarma Benazir Bhutto Institute of Trauma from January 2018 to April 2019. TBI patients ≥16 years of age that were admitted to the intensive care unit (ICU) or high dependency unit (HDU) and managed conservatively or surgically, were included. Central nervous system (CNS) infection, mortality and associated risk factors were noted.Results: The mean age was 30.9 ± 13.6 years with 116 (91.3%) males. CNS infection developed in 72 (56.7%) patients. Of 72, 29 (40%) had positive CSF culture and in 28 (38.8 %) multidrug resistant Acinetobacterspp. susceptibile to only colistin was reported. Antimicrobial therapy with intravenous colistin with meropenem was used in 63 (87.5%) patients. A significant association of CNS infection was found with age (p-value 0.047), cerebrospinal fluid (CSF) leak at presentation (p-value 0.045), type of surgery (p-value 0.001), and duration of ER stay (p-value 0.047). Mortality occurred in 83 (65.4%) patients. A significant association of mortality was found with low Glasgow coma score (GCS) at presentation (p-value 0.031), CSF leak at presentation (p-value <0.001), intraventricular hemorrhage, TBI type (p-value <0.001), polytrauma (p-value 0.003), CNS infection (p-value <0.001), and duration of emergencyroom stay (p-value 0.009).Conclusion High mortality was observed in patients with traumatic brain injury. Intracranial infection is strongly correlated with mortality underscoring the need for strict infection control and prevention measures.

Antimicrobial resistance profiles and associated factors of Acinetobacter and Pseudomonas aeruginosa nosocomial infection among patients admitted at Dessie comprehensive specialized Hospital, North-East Ethiopia. A cross-sectional study.

IntroductionHospital admitted patients are at increased risk of nosocomial infections (NIs) with multi-drug resistant (MDR) pathogens which are prevalent in the hospital environment. Pseudomonas aeruginosa (P. aeruginosa) and Acinetobacter baumannii (A. baumannii) are common causes of NIs worldwide. The objective of this study is to determine antimicrobial resistance profiles and associated factors of Acinetobacter spp and P. aeruginosa NIs among hospitalized patients.MethodsA cross-sectional study was conducted at Dessie comprehensive specialized hospital, North-East Ethiopia, from February 1 to April 30, 2020. A total of 254 patients who were suspected of the bloodstream, urinary tract, or surgical site nosocomial infections were enrolled consecutively. Socio-demographic and other variables of interest were collected using a structured questionnaire. Specimens were collected and processed following standard microbiological procedures. Antimicrobial susceptibility was determined using the Kirby-Bauer disk diffusion method following Clinical and Laboratory Standards Institute guidelines. Data were analyzed with SPSS version 23 and p-value < 0.05 was considered statistically significant.ResultsOverall, 13% of patients had nosocomial Acinetobacter spp and/or P. aeruginosa infections. The culture positivity rate was 16(6.3%) for Acinetobacter spp and 18(7.1%) for P. aeruginosa. Patients admitted in the surgical ward (Adjusted odds ratio (AOR):10.66;95% confidence interval (CI):1.22–93.23), pediatric ward (AOR:14.37;95%CI:1.4–148.5), intensive care unit (AOR:41.93;95%CI:4.7–374.7) and orthopedics (AOR:52.21;95%CI:7.5–365) were significantly at risk to develop NIs compared to patients admitted in the medical ward. Patients who took more than two antimicrobial types at admission were 94% (AOR:0.06; 95% CI:0.004–0.84) times more protected from NIs compared to those who did not take any antimicrobial. About 81% of Acinetobacter spp and 83% of P. aeruginosa isolates were MDR. Amikacin and meropenem showed promising activity against Acinetobacter spp and P. aeruginosa isolates.ConclusionThe high prevalence of MDR Acinetobacter spp and P. aeruginosa nosocomial isolates enforce treating of patients with NIs based on antimicrobial susceptibility testing results.

AB569, a non-toxic combination of acidified nitrite and EDTA, is effective at killing the notorious Iraq/Afghanistan combat wound pathogens, multi-drug resistant Acinetobacter baumannii and Acinetobacter spp.

Multi-drug resistant (MDR) Acinetobacter baumannii (Ab) and Acinetobacter spp. present monumental global health challenges. These organisms represent model Gram-negative pathogens with known antibiotic resistance and biofilm-forming properties. Herein, a novel, nontoxic biocide, AB569, consisting of acidified nitrite (A-NO2-) and ethylenediaminetetraacetic acid (EDTA), demonstrated bactericidal activity against all Ab and Acinetobacter spp. strains, respectively. Average fractional inhibitory concentrations (FICs) of 0.25 mM EDTA plus 4 mM A-NO2- were observed across several clinical reference and multiple combat wound isolates from the Iraq/Afghanistan wars. Importantly, toxicity testing on human dermal fibroblasts (HDFa) revealed an upper toxicity limit of 3 mM EDTA plus 64 mM A-NO2-, and thus are in the therapeutic range for effective Ab and Acinetobacter spp. treatment. Following treatment of Ab strain ATCC 19606 with AB569, quantitative PCR analysis of selected genes products to be responsive to AB569 revealed up-regulation of iron regulated genes involved in siderophore production, siderophore biosynthesis non-ribosomal peptide synthetase module (SBNRPSM), and siderophore biosynthesis protein monooxygenase (SBPM) when compared to untreated organisms. Taken together, treating Ab infections with AB569 at inhibitory concentrations reveals the potential clinical application of preventing Ab from gaining an early growth advantage during infection followed by extensive bactericidal activity upon subsequent exposures.

Investigation of the association of virulence genes and biofilm production with infection and bacterial colonization processes in multidrug-resistant Acinetobacter spp.

The aim of this study was to evaluate the phenotypic and molecular patterns of biofilm formation in infection and colonization isolates of Acinetobacter spp. from patients who were admitted in a public hospital of Recife-PE-Brazil in 2018-2019. For the biofilm phenotypic analysis, Acinetobacter spp. isolates were evaluated by the crystal violet staining method; the search of virulence genes (bap, ompA, epsA, csuE and bfmS) was performed by PCR; and the ERIC-PCR was performed for molecular typing. Amongst the 38 Acinetobacter spp. isolates, 20 were isolated from infections and 18 from colonization. The resistance profile pointed that 86.85% (33/38) of the isolates were multidrug-resistant, being three infection isolates, and two colonization isolates resistant to polymyxin B. All the isolates were able to produce biofilm and they had at least one of the investigated virulence genes on their molecular profile, but the bap gene was found in 100% of them. No clones were detected by ERIC-PCR. There was no correlation between biofilm formation and the resistance profile of the bacteria, neither to the molecular profile of the virulence genes. Thus, the ability of Acinetobacter spp. to form biofilm is probably related to the high frequency of virulence genes.

Acinetobacter Spp: Resistance and therapeutic decisions at the turn of the novel millennium

Background: This study was planned to evaluate sample wise isolation and antimicrobial resistant trends of Acinetobacter spp. in different departments of a tertiary care hospital. Methods and materials: This was a transversal descriptive study, carried out in the clinical microbiology laboratory of the Allama Iqbal Medical College/Jinnah Hospital, Lahore, Pakistan, during the period of January 2015 to December 2016. Every clinical specimen was processed for bacterial culture and antimicrobial susceptibly testing. A total of 3590 (2015 = 1780, 2016 = 1810) clinical specimens were processed. Results: Of the total, only 54.7% were gram-negative, among these Acinetobacter spp. were isolated from 10.1% and 16.5% samples respectively in 2015–16 with an overall rate of 24.3%. The highest occurrence of Acinetobacter spp. isolates was reported from Intensive care units (ICU) (54%) followed by surgical units (25%) and medical units (16%). It is noteworthy that ICU and internal medicine showed the highest resistance rates, whereas, lower resistance rate was observed for the outdoor patients (OPD). Although collistin showed 0% resistant while ceftriaxone, ciprofloxacin, gentamicin, and tigecycline showed 90%, 68%, 66%, 66% and 62% resistance against Acinetobacter spp. respectively. An alarming increase in the resistance rate of meropenem, cefoperazone/sulbactam, piperacillin/tazobactam, ciprofloxacin, and imipenem was observed from the year 2015 to 2016. Conclusion: This startling resistance acquired by Acinetobacter spp. within a period of one year, represent very limited therapeutic options left for the infections caused by Acinetobacter spp. Unavailability of effective drugs and limited therapeutic options enforce the health care practitioners to prescribe expensive and broad range antibiotics, which may cause harm to the patient. Therefore, it is need of an hour to better understand the antimicrobial patterns and optimize antimicrobial prescription policies for the control of multidrug-resistant Acinetobacter spp.

Evolution of Acinetobacter baumannii infections and antimicrobial resistance. A review

Abstract The emergence of multi-drug resistant Acinetobacter spp involved in hospital-acquired infections, once considered an easily treatable pathogen, is troublesome and an immense burden for the modern medical systems worldwide. In the last 20 years the medical community recorded an increase in the incidence and severity of these infections as therapeutic means tend to be less and less effective on these strains. The ability of these bacteria to rapidly develop resistance to antimicrobial agents by continuously changing and adapting their mechanisms, their ability to survive for long periods of time in the hospital environment and the multitude of transmission possibilities raises serious issues regarding the management of these complex infections. The future lies in developing new and targeted methods for the early diagnosis of A. baumannii, as well as in the judicious use of antimicrobial drugs. This review details the evolution of the pathogenicity of this microorganism, together with the changes that appeared in resistance mechanisms and the advancements in molecular testing for the early detection of infection.

Effectiveness of antimicrobial hospital curtains on reducing bacterial contamination-A multicenter study.

To determine the efficacy of 2 types of antimicrobial privacy curtains in clinical settings and the costs involved in replacing standard curtains with antimicrobial curtains. A prospective, open-labeled, multicenter study with a follow-up duration of 6 months. This study included 12 rooms of patients with multidrug-resistant organisms (MDROs) (668 patient bed days) and 10 cubicles (8,839 patient bed days) in the medical, surgical, neurosurgical, orthopedics, and rehabilitation units of 10 hospitals. Culture samples were collected from curtain surfaces twice a week for 2 weeks, followed by weekly intervals. With a median hanging time of 173 days, antimicrobial curtain B (quaternary ammonium chlorides [QAC] plus polyorganosiloxane) was highly effective in reducing the bioburden (colony-forming units/100 cm2, 1 vs 57; P < .001) compared with the standard curtain. The percentages of MDRO contamination were also significantly lower on antimicrobial curtain B than the standard curtain: methicillin-resistant Staphylococcus aureus, 0.5% vs 24% (P < .001); carbapenem-resistant Acinetobacter spp, 0.2% vs 22.1% (P < .001); multidrug-resistant Acinetobacter spp, 0% vs 13.2% (P < .001). Notably, the median time to first contamination by MDROs was 27.6 times longer for antimicrobial curtain B than for the standard curtain (138 days vs 5 days; P = .001). Antimicrobial curtain B (QAC plus polyorganosiloxane) but not antimicrobial curtain A (built-in silver) effectively reduced the microbial burden and MDRO contamination compared with the standard curtain, even after extended use in an active clinical setting. The antimicrobial curtain provided an opportunity to avert indirect costs related to curtain changing and laundering in addition to improving patient safety.

Effectiveness of targeted enhanced terminal room disinfection on hospital-wide acquisition and infection with multidrug-resistant organisms and Clostridium difficile: a secondary analysis of a multicentre cluster randomised controlled trial with crossover design (BETR Disinfection)

The hospital environment is a source of pathogen transmission. The effect of enhanced disinfection strategies on the hospital-wide incidence of infection has not been investigated in a multicentre, randomised controlled trial. We aimed to assess the effectiveness of four disinfection strategies on hospital-wide incidence of multidrug-resistant organisms and Clostridium difficile in the Benefits of Enhanced Terminal Room (BETR) Disinfection study. We did a prespecified secondary analysis of the results from the BETR Disinfection study, a pragmatic, multicentre, crossover cluster-randomised trial that assessed four different strategies for terminal room disinfection in nine hospitals in the southeastern USA. Rooms from which a patient with a specific infection or colonisation (due to the target organisms C difficile, meticillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci (VRE), or multidrug-resistant Acinetobacter spp) was discharged were terminally disinfected with one of four strategies: standard disinfection (quaternary ammonium disinfectant, except for C difficile, for which 10% hypochlorite [bleach] was used; reference); standard disinfection and disinfecting ultraviolet light (UV-C), except for C difficile, for which bleach and UV-C was used (UV strategy); 10% hypochlorite (bleach strategy); and bleach and UV-C (bleach and UV strategy). We randomly assigned the sequence of strategies for each hospital (1:1:1:1), and each strategy was used for 7 months, including a 1-month wash-in period and 6 months of data collection. The prespecified secondary outcomes were hospital-wide, hospital-acquired incidence of all target organisms (calculated as number of patients with hospital-acquired infection with a target organism per 10 000 patient days), and hospital-wide, hospital-acquired incidence of each target organism separately. BETR Disinfection is registered with ClinicalTrials.gov, number NCT01579370. Between April, 2012, and July, 2014, there were 271 740 unique patients with 375 918 admissions. 314 610 admissions met all inclusion criteria (n=73 071 in the reference study period, n=81 621 in the UV study period, n=78 760 in the bleach study period, and n=81 158 in the bleach and UV study period). 2681 incidenct cases of hospital-acquired infection or colonisation occurred during the study. There was no significant difference in the hospital-wide risk of target organism acquisition between standard disinfection and the three enhanced terminal disinfection strategies for all target multidrug-resistant organisms (UV study period relative risk [RR] 0·89, 95% CI 0·79-1·00; p=0·052; bleach study period 0·92, 0·79-1·08; p=0·32; bleach and UV study period 0·99, 0·89-1·11; p=0·89). The decrease in risk in the UV study period was driven by decreases in risk of acquisition of C difficile (RR 0·89, 95% CI 0·80-0·99; p=0·031) and VRE (0·56, 0·31-0·996; p=0·048). Enhanced terminal room disinfection with UV in a targeted subset of high-risk rooms led to a decrease in hospital-wide incidence of C difficile and VRE. Enhanced disinfection overcomes limitations of standard disinfection strategies and is a potential strategy to reduce the risk of acquisition of multidrug-resistant organisms and C difficile. US Centers for Disease Control and Prevention.

Attributable Risk and Time Course of Colistin-Associated Acute Kidney Injury.

Despite colistin's longstanding reported association with nephrotoxicity, the attributable risk and timing of toxicity onset are still unknown. Whether substantial toxicity occurs during the initial 72 hours of exposure has important implications for early treatment decisions. The objective of this study was to compare colistin-exposed patients with a matched control group given other broad spectrum antibiotics. We conducted a retrospective cohort study in patients treated for multidrug-resistant Pseudomonas, Klebsiella, or Acinetobacter spp. Colistin-exposed patients were matched to unexposed controls using propensity scores. AKI was defined according to the Kidney Disease Improving Global Outcomes creatinine criteria. Incidence rate ratios and risk differences of AKI in the matched cohort were estimated with the generalized estimating equation Poisson regression model. Risk factors for AKI were tested for effect modification in the matched cohort. The study included 150 propensity-matched pairs with similar types of infection, similar delays to effective treatment, and similar baseline characteristics. Incidence of AKI was 77 of 150 (51%) in the colistin group versus 33 of 150 (22%) in matched controls (risk difference, 29%; 95% confidence interval, 19 to 39), corresponding to a number needed to harm of 3.5. Early toxicity was apparent, because AKI risk was higher in colistin-exposed patients at 72 hours of exposure (incidence rate ratio, 1.9; 95% confidence interval, 1.1 to 3.5). In both groups, hospital mortality in patients who experienced AKI was lower if kidney function returned to baseline during hospitalization. The effect of colistin exposure on AKI risk varied inversely according to baseline hemoglobin concentration. Colistin is associated with substantial excess AKI that is apparent within the first 72 hours of treatment. Colistin's toxicity varied according to baseline hemoglobin concentration. This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2018_03_15_CJASNPodcast_18_4_M.mp3.

High Proportions of Multidrug-Resistant Acinetobacter spp. Isolates in a District in Western India: A Four-Year Antibiotic Susceptibility Study of Clinical Isolates.

The purpose of the study was to determine the proportions of multidrug-resistant (MDR) Acinetobacter spp. isolates from the district of Nashik in Western India during the period from 2011–2014. Antibacterial susceptibility testing of isolates from inpatients and outpatients was performed using Kirby–Bauer disc diffusion method to determine inhibitory zone diameters. Proportions of non-susceptible isolates were calculated from the antibacterial susceptibility data. MDR was defined as an isolate being non-susceptible to at least one antibacterial agent in at least three antibacterial categories. The change in proportions of MDR isolates; extended-spectrum β-lactamase (ESBL)-producing isolates; and non-susceptible isolates to specific antibacterial categories over calendar time was investigated by logistic regression. The proportions of MDR and ESBL-producing isolates ranged from 89.4% to 95.9% and from 87.9% to 94.0%; respectively. The proportions of non-susceptible isolates to aminoglycosides; carbapenems; antipseudomonal penicillins/β-lactamase inhibitors; cephalosporins; folate pathway inhibitors; or penicillins/β-lactamase inhibitors exceeded 77.5%. Proportions of fluoroquinolone and tetracycline non-susceptible isolates ranged from 65.3% to 83.3% and from 71.3% to 75.9%; respectively. No changes in trends were observed over time; except for a decreasing trend in fluoroquinolone non-susceptible isolates (OR = 0.75 (95% CI, 0.62–0.91)). Significantly higher proportions of non-susceptible; MDR and ESBL-producing isolates were found among isolates from the respiratory system compared to isolates from all other specimen types (p < 0.05). High proportions of MDR Acinetobacter spp. isolates were observed in the period from 2011–2014. Antimicrobial stewardship programmes are needed to prevent the emergence and spread of antibiotic resistance.

Bloodstream infections caused by Acinetobacter species with reduced susceptibility to tigecycline: clinical features and risk factors

IntroductionDuring recent decades, the rates of multidrug resistance, including resistance to carbapenems, have increased dramatically among Acinetobacter species. Tigecycline has activity against multidrug-resistant Acinetobacter spp, including carbapenem-resistant isolates. However, reports of tigecycline-resistant Acinetobacter spp are emerging from different parts of the world. The purpose of this study was to evaluate potential risk factors associated with tigecycline non-susceptible Acinetobacter bacteremia. MethodsThe medical records of 152 patients with Acinetobacter bacteremia attending Samsung Medical Center between January 2010 and December 2014 were reviewed. Non-susceptibility to tigecycline was defined as a minimum inhibitory concentration (MIC) of tigecycline ≥4μg/ml. Cases were patients with tigecycline non-susceptible Acinetobacter bacteremia and controls were those with tigecycline-susceptible Acinetobacter bacteremia. ResultsOf the 152 patients included in the study, 61 (40.1%) had tigecycline non-susceptible Acinetobacter bacteremia (case group). These patients were compared to 91 patients with tigecycline-susceptible Acinetobacter bacteremia (control group). The case group showed high resistance to other antibiotics (>90%) except colistin (6.6%) and minocycline (9.8%) when compared to the control group, which exhibited relatively low resistance to other antibiotics (<50%). Multivariate analysis showed that recent exposure to corticosteroids (minimum 20mg per day for more than 5 days within 2 weeks) (adjusted odds ratio (OR) 2.887, 95% confidence interval (CI) 1.170–7.126) and carbapenems (within 2 weeks) (adjusted OR 4.437, 95% CI 1.970–9.991) were significantly associated with tigecycline non-susceptible Acinetobacter bacteremia. Although prior exposure to tigecycline was more common in the case group than in the control group (9.8%, 6/61 vs. 2.2%, 2/91; p=0.046), this variable was found not to be a significant factor associated with tigecycline non-susceptibility after adjustment for other variables (adjusted OR 1.884, 95% CI 0.298–11.920; p=0.501). ConclusionsThese data suggest that tigecycline non-susceptible Acinetobacter spp have emerged and disseminated in the hospital in association with a recent exposure to carbapenems and an immunosuppressed state. This indicates that the rational use of antibiotics through a comprehensive antimicrobial stewardship program, especially in immunosuppressed patients, may be essential in limiting the emergence and spread of multidrug-resistant organisms such as tigecycline-resistant Acinetobacter spp, which are difficult to treat.

Lettuce and fruits as a source of multidrug resistant Acinetobacter spp.

The role of ready-to-eat products as a reservoir of pathogenic species of Acinetobacter remains unclear. The objective of the present study was to evaluate the presence of Acinetobacter species in lettuces and fruits marketed in Portugal, and their susceptibility to antimicrobials. Acinetobacter spp. were isolated from 77.9% of the samples and these microorganisms were also found as endophytes (i.e. present within the plant tissue) in 12 of 20 samples of lettuces analysed. Among 253 isolates that were identified as belonging to this genus, 181 presented different PFGE profiles, representing different strains. Based on the analysis of the partial sequence of rpoB, 175 strains were identified as members of eighteen distinct species and the remaining six strains may represent five new candidate species since their rpoB sequence similarities with type strains were less than 95%. Acinetobacter calcoaceticus and Acinetobacter johnsonii were the most common species, both with the frequency of 26.5%; and 11% of the strains belong to the Acinetobacter baumannii group (i.e. A. baumannii, Acinetobacter pittii, Acinetobacter seifertii and Acinetobacter nosocomialis), which is most frequently associated with nosocomial infections.Overall, the strains were least susceptible to piperacillin (80.1%), piperacillin-tazobactam (64.1%), ceftazidime (43.1%), ciprofloxacin (16.6%), trimethoprim-sulfamethoxazole (14.9%), imipenem (14.4%) and colistin (13.3%). The most active antimicrobials were minocycline and tetracycline, with 0.6% and 3.9% of strains resistant, respectively. About 29.8% of the strains were classified as multidrug-resistant (MDR), 4.4% as extensively drug-resistant (XDR) and the prevalence of MDR strains within the A. baumannii group (25%) was similar to other species (30.4%). The presence of clinically important species as well as MDR strains in lettuces and fruits may be a threat to public health considering that they may transmit these pathogens to environments such as the community and hospital settings.

Multidrug Resistant Acinetobacter Spp. Blood Stream Infection in A Neonatal Intensive Care Unit of An Urban Specialized Hospital in Dhaka

Background: Acinetobacter spp. are ubiquitous in the environment, that is, soil and water, and occasionally isolated from mucous membrane, secretion, and skin of hospitalized patients, also on surfaces of hospital environment. Antibiotic resistant Acinetobacter spp. blood stream infection is a leading problem. Multidrug resistant Acinetobacter spp. blood infection in the neonatal intensive care unit (NICU) patients create a great problem in hospital settings.Methods: This study was carried out from January to December 2011 based on the clinical specimens obtained from suspected cases of septicemia patients admitted in the NICU of Addin Women’s Medical College Hospital, Dhaka, Bangladesh. Blood collected from suspected cases by maintaining strict aseptic precaution and sent immediately to microbiology laboratory of the same institution. Samples were also taken from different sites in NICU and Department of Obstetrics &amp; Gynaecology operation theatre for detection of the sources of infection in outbreak situation. Isolated organisms were identified by standard bacteriological method and drug susceptibility test had been done by modified Kirby Bauer disk diffusion technique.Results: A total 87 blood culture positive cases were included in this study. Out of 87 culture positive cases Acinetobacter spp. was the predominant pathogen 32 (35.58%). Acinetobacterspp isolated from the blood of newborn and the mortality rate was 3.33%. Acinetobacter blood stream infection is more common in the first 7 days of life (early onset) , birth weight less than 2 kg ( 56.6%), also affected the baby with birth weight more than 2.5 Kg (23.3%) and most of the neonates having gestational age less than 37 weeks (70%). Twenty four babies (80%) were delivered in the same hospital. Acinetobacter spp. showed increased resistance against majority of antibiotics such ascolistin 3.12%, levofloxacin 40.62%, imipenem 53.12%, cotrimeoxazole 54.54%, pipericillin tazobactum 59.37%, amikacin 75%, ciprofloxacin 78.12%,gentamycin 84.37%, amoxyclavulonic acid 93.75%, ceftriaxone, ceftazidime and cefixime 96.87% cefuroxime, cephradineand ampicillin 100% respectively. We categorized the Acinetobacter spp. in to 3 categories, such as multidrug resistant (MDR) 37.5%, extensive drug resistant (XDR) 28.12% and pandrug resistant (PDR) 3.12% Miscellaneous pattern of sensitivity 31.15%. A cluster of cases occurred in month June, which was quite higher than other months, Surveillance had been done. Acinetobacter spp. isolated from the environment of operation theatre of Obstetrics and Gynea department. In NICU, Acinetobacter spp were isolated from suction water, suction tube, incubator door handle and body surface of the neonates. Acinetobacter spp. which were isolated from suction tube and suction water were only sensitive to colistin and resistant to other drugs. Two Acinetobacter spp. were alsoisolated from OT environment and body surface of neonates which were found sensitive to only imipenem and colistin. Acinetobacter spp. isolated from incubator door handle was sensitive to colistin, imipenem, amikacin, gentamycin, levofloxacin, ciprofloxacin, piperacillin tazobactum and cotrimoxazole.J Dhaka Medical College, Vol. 24, No.1, April, 2015, Page 47-52

Successful treatment of prosthetic joint infection with multidrug-resistant Acinetobacter species with debridement and retention: a case report

Acinetobacter spp. is mainly addressed in the entity of healthcare associated infections. The organism has developed substantial antimicrobial resistance, making treatment of infections attributed to A. baumannii more difficult to manage. Prosthetic joint infection caused by Acinetobacter spp. is uncommon and only few case reports were found in the literature. This case alerts clinicians regarding the unusual aetiology of a prosthetic joint infection caused by multidrug resistant Acinetobacter spp . In such situations early institution of appropriate antibiotics is of utmost importance to combat the infection.

Frist Detection of The blaOXA-23 Genes in Clinical Isolates of Acinetobacterbaumanniiin Babylon Hospitals-Iraq

Acinetobacter spp. have risen as important pathogens in medicinal services related contaminations. Carbapenems are vital antimicrobial agents for treating diseases due to multidrug resistant Acinetobacter spp. Resistance to these drugs in the genus, may beconferred by different mechanisms particularly production of class D carbapenemases. OXA-23-like family has been brought up as one of the dominating carbapenemases among Acinetobacter. The present study aimed to investigate the occurrence of OXA-23-like carbapenemases among Acinetobacterisolatesrecovered from patients of hospitals in Babylon, Iraq. Antimicrobial susceptibility profiles were determined by disk-diffusion method.Imipenem resistant isolates were submitted to Modified Hodge Test and Double Disk Synergy Test to screen for carbapenemase generation, and later to polymerase chain reaction (PCR) to explore the presence of blaOXA-23 genes . One (10%) of isolates was observed to be imipenem and meropenem resistant (MIC > 512 μg/ml). 6(60%) gave positive results with the imipenem-EDTA disk and Modified Hodge test ; 4 isolates (40%) as indicated by PCR results, carried the blaOXA-23 genes. OXA-23-like enzymes might be a critical component of carbapenem resistance among isolates present in the hospitals studied. Keywords: blaOXA-23, Acinetobacter, Oxacillinase, Carbapenem, MDR)

Evaluation of multiple antibiotic resistance (MAR) index and Doxycycline susceptibility of Acinetobacter species among inpatients

Background: Background: Acinetobacter is contributing to increased morbidity and mortality with its strong propensity to colonize and disseminate among humans and environmental sources. Methods & Materials: Clinical isolates of Acinetobacter species recovered from inpatients of tertiary care institute in North West India were analyzed retrospectively along with their antibiogram to evaluate in vitro activity of Doxycycline. Isolates resistant to more than three different groups of antimicrobials were considered to be multidrug resistant (MDR).MAR index was calculated and interpreted. Results: A total 93 isolates of Acinetobacter species were recovered from inpatients, out of which predominant were from urine 47(50.54%) followed by blood 27(29.03%) samples. MDR isolates were 57(61.29%) with majority from urine 35 (61.40%) and blood samples 8(14.04%). Overall antimicrobial susceptibility pattern revealed Imipenem (75.27%), Meropenem (68.82%) and Doxycycline (68.82%) to be most efficacious drugs whereas in MDR Acinetobacter spp most promising drug was Doxycycline,with highest sensitivity rate (66.67%) followed by carbapenems namely Imipenem (61.40%) and Meropenem (52.63%) . MAR index revealed 71 isolates (76.34%) with MAR index greater than 0.2 and 22 (23.66%) less than 0.2. However, three isolates had shown MAR index of 01 (i.e. resistant to all the antimicrobials tested), out of which two were recovered from intensive care unit and one from general surgery ward. Isolates with MAR index greater than 0.2 were mainly isolated from patients admitted in General surgery ward 20 (28.17%), intensive care units 19 (26.76%) and gynecology/ obstetrics ward 17 (23.94%). Twenty six multi drug resistance patterns were observed for Acinetobacter species for the nine antimicrobials tested. Resistance to COT, CIP, GEN, AK, A/S, CPM, IMP, MRP (R8)̊̊ was most frequently observed pattern in 8(14.04%) of MDR isolates Conclusion: MDR Acinetobacter is emerging as predominant pathogen in hospital settings . In current study Doxycycline has exhibited efficacy against MDR Acinetobacter, which can be considered as an alternative therapy to down regulate selective pressure on carbapenems. In low resource settings, antibiogram along with MAR index serve an important epidemiological tool to monitor drug resistance in Acinetobacter species among inpatients as it is becoming more difficult to treat this pathogen due to the restricted pharmaceutical and therapeutic armamentarium.

Collateral benefit of screening patients for methicillin-resistant Staphylococcus aureus at hospital admission: Isolation of patients with multidrug-resistant gram-negative bacteria

Surveillance at hospital admission for multidrug-resistant (MDR) gram-negative bacteria (GNB) is not often performed, potentially leaving patients carrying these organisms unrecognized and not placed in transmission precautions until they develop infection. Veterans Affairs (VA) facilities screen all admissions for methicillin-resistant Staphylococcus aureus (MRSA) and place positive patients in contact precautions. We assessed how often patients with MDR GNB in clinical cultures obtained within 30days following admission would have been in contact precautions because of a positive MRSA admission screen. MRSA screening and MDR GNB culture results were extracted from a database of patients admitted to all VA acute care medical facilities from January 2009-December2012. Of patients with MDR GNB-positive cultures within 30days following admission, up to 44.3% (dependent on bacterial species) would have been in contact precautions because of a clinical positive admission MRSA nasal screen. Admissions with a positive MRSA screen had odds for MDR GNB in a culture 2.5 times greater than those with a negative screen (95% confidence interval [CI], 2.4-2.6). Odds ratios were 2.4 (95% CI, 2.3-2.5) for MDR Enterobacteriaceae, 2.7 (95% CI, 2.5-2.9) for MDR Pseudomonas aeruginosa, and 4.3 (95% CI, 3.8-4.8) for MDR Acinetobacter spp. Patients may be serendipitously placed in contact precautions for MDR GNB when isolated for a positive admission MRSA screen.

Global transcriptional response of Acinetobacter baumannii to a subinhibitory concentration of tigecycline

Acinetobacter baumannii has emerged as a significant nosocomial pathogen worldwide. Multidrug resistance has limited the treatment options for A. baumannii. Tigecycline belongs to a new class of modified tetracycline antimicrobials known as glycylcyclines and has demonstrated good in vitro antimicrobial activity against multidrug-resistant Acinetobacter spp. However, tigecycline-resistant strains may be generated during treatment. To explore the response to tigecycline in A. baumannii, the transcriptional profile of A. baumannii was determined in the presence and absence of tigecycline. The results showed that a major facilitator superfamily (MFS) efflux pump and multiple transcriptional regulators possibly involved in the stress response and drug resistance were upregulated in response to tigecycline. Strong suppressors in the aerobic phenylacetate catabolic pathway and a number of ATP-binding cassette (ABC) transporters were also observed after exposure to tigecycline. Furthermore, A. baumannii showed a lower minimum inhibitory concentration of ceftazidime in the presence of tigecycline owing to downregulated OXA-23 and AmpC. These finding suggest that the response of A. baumannii to tigecycline is multifactorial and includes MFS family efflux pump transcriptional regulators and metabolic pathways, such as the phenylacetate catabolic pathway.

Risk factors and clinical outcome ofsulbactam nonsusceptibility inmonomicrobial Acinetobacter nosocomialis bacteremia.

Sulbactam is an effective antimicrobial agent against multidrug-resistant Acinetobacter spp. This retrospective study evaluated the risk factors of sulbactam nonsusceptibility (SNS) in monomicrobial Acinetobacter nosocomialis bacteremia and its related outcome. This 9-year retrospective study included 267 patients who were admitted to a large teaching hospital in Taiwan with monomicrobial A. nosocomialis bacteremia. A. nosocomialis was identified to the species level using molecular methods. Antimicrobial susceptibilities were determined by the agar dilution method. To identify the risk factors of acquiring resistant strains, significant clinical variables derived from univariate analysis were entered into multivariate analysis. Polymerase chain reaction was used to identify blaTEM. Clonality was determined by pulsed-field gel electrophoresis. A total of 41 of the 267 patients (15.4%) had SNS A. nosocomialis bacteremia. Compared to those with susceptible strains, these patients had higher 14-day mortality (17.1% vs. 7.5%, p=0.049), were more likely to have higher Acute Physiology and Chronic Health Evaluation (APACHE) II score, were more frequently admitted to the intensive care unit, and had previously received broad-spectrum antibiotics and underwent invasive procedures. In multivariate analysis, the independent risk factors were high APACHE II score and prior use of arterial line [odds ratio (OR), 1.048; 95% confidence interval (CI), 1.007-1.091; p=0.022 and OR, 2.936; 95% CI, 1.339-6.441; p=0.007, respectively]. No outbreak was identified and SNS isolates did not harbor blaTEM. For monomicrobial A. nosocomialis bacteremia, the mortality of patients with SNS strains was higher. The SNS strains are more commonly recovered from patients with higher APACHE score and receiving more invasive procedures, especially arterial line.

Characterization of the Multidrug-ResistantAcinetobacterspecies Causing a Nosocomial Outbreak at Intensive Care Units in a Korean Teaching Hospital: Suggesting the Correlations with the Clinical and Environmental Samples, Including Respiratory Tract-related Instruments

Background: Acinetobacter spp. is an important nosocomial pathogen for which increasing resistance to multiple antimicrobial agents has been observed. Prevalence of multidrug-resistant (MDR) Acinetobacter spp. in the intensive care unit (ICU) at a teaching hospital in Korea started to increase in 2008. The aim of this study was to determine the source of pathogen spread and to characterize the emerging strains at an early stage of outbreak. Methods: Samples from respiratory instruments and fomites in the ICUs, as well as from the healthcare workers, were cultured to identify the sources of MDR Acinetobacter spp. Antimicrobial susceptibility was determined by the CLSI disk diffusion method. Pulsed field gel electrophoresis (PFGE) was performed for clinical and environmental isolates in order to determine clonality. Carbapenemase genes were detected by multiplex PCR. Infection control measures including peer-monitoring of hand washing, environmental cleaning and standard precautions were enforced. Results: Among the samples from the ICU tools (105) and healthcare worker’s hands (44), 31 (30%) and 2 (5%) respective samples yielded MDR Acinetobacter spp. Among the environmental samples, 90% were from respiratory-related equipment. The majority of clinical and environmental MDR Acinetobacter spp. (44/55) belonged to the pulsotype A. baumannii and carried both blaOXA-51-like and blaOXA-23-like genes. Even though infection-control measures were enforced, prevalence of MDR Acinetobacter spp. continues to increase. Conclusion: An outbreak of MDR Acinetobacter spp. in a Korean hospital was caused by A. baumannii carrying the blaOXA-23-gene and was correlated with contaminated respiratory-related instruments in the ICUs. More intensive measures for nosocomial infection control are needed for successful prevention of Acinetobacter spread in hospitals. (Ann Clin Microbiol 2014;17:29-34)