Detection of Multi-drug Resistant Acinetobacter Lwoffii Isolated from Soil of Mink Farm

There were 4 Acinetobacter lwoffii obtained from soil samples.The antimicrobial susceptibility of the strains to 16 antimicrobial agents was investigated using K-B method.Three isolates showed the multi-drug resistance.The presence of resistance genes and integrons was determined using PCR.The aadA 1,aac（3＇）-IIc,aph（3＇）-VII,aac（6＇）-Ib,sul2,cat2,floR,and tet（K）genes were detected,respectively.

中药在控制耐药菌Acinetobacter baumannii繁殖中的研究进展

鲍曼不动杆菌存在多重耐药性,感染后可选择抗菌药物有限,病死率高,抗鲍曼不动杆菌感染是目前临床研究领域的重点和难点。部分中药表现出抑制鲍曼不动杆菌生长的作用,但是其抗菌机制尚不清楚。基于此,本文系统综述了近年来中草药在控制鲍曼不动杆菌感染方面的研究进展,以期为中药抗菌药物的研发提供依据。

Direct and Residual Microbicidal Efficacy of Various Antiseptics against Multi-Drug Resistant Bacteria

Background: Infections in ICU’s patients are known to often originate from the colonization of wounds by the patient’s endogenous microbiota, and to eventually lead to secondary sepsis. Aim: to compare in vitro the direct and residual effects after different exposure times of 4% chlorhexidine, and of 0.1% and 0.04% polyhexanide (in gel and solution forms), on ATCC-microorganisms, and too, on bacterial strains obtained from ICU patients. Methods: We used wild multi-drug resistant strains recently obtained from the wounds of patients hospitalized at ICU and reference strains from the American Type Culture Collection (ATCC). Chlorhexidine 4% was studied as a reference solution. The direct and residual effects of the 0.1% and 0.04% polyhexanide, in gel and solution forms, were analyzed using cotton germ carriers. To evaluate the direct effect, we exposed the strains to the antiseptic. To assess the residual effect, the germ-carriers were impregnated with antiseptic and were allowed to dry before we contaminated them. We inoculated the germ carriers in a culture medium with an inhibitor of antiseptic effect to count the number of surviving microorganisms. Findings: 0.1% Polyhexanide solution proved a direct and residual efficacy after 24 hours equivalent to 4% chlorhexidine. Is very important to highlight that this great efficacy did not change according to whether they were ATCC or multidrug-resistant strains. Conclusions: 0.1% polyhexanide demonstrated a great direct and residual efficacy (like 4% chlorhexidine), against multi-drug resistant strains isolated from ICU’s patients. Moreover, due to its few cytotoxicity against keratinocytes and fibroblasts can be an optimal antiseptic for burns, wounds or ulcers.

Analysis of Multi-Drug Resistant Organism Surveillance and Antimicrobial Resistance Early Warning in a Hospital in 2022

Objective:To determine the clinical distribution of multi-drug resistant organism(MDRO)in Jiangyan Hospital and the monitoring and warning of drug-resistance bacteria to provide an important basis for guiding the application of broad-spectrum antibiotics in clinical treatment and reducing the occurrence of nosocomial infection.Methods:Retrospective screening and analysis were conducted on the pathogenic strains of hospitalized patients in our hospital in 2022.Results:A total of 2,769 strains of pathogenic bacteria and 390 strains of MDRO were detected and isolated in our hospital in 2022;the detection rate of MDRO was 14.08%.A total of 516 strains(18.64%)Klebsiella pneumoniae(KP)and 62 strains(12.02%)of carbapenem-resistant Klebsiella pneumoniae(CR-KP)were detected;436 strains(15.75%)of Escherichia coli(ECO)were detected,including 8 strains(1.83%)of CR-ECO;342 strains(12.35%)of Pseudomonas aeruginosa(PA)and 116 strains(33.92%)of CR-PA were detected;there were 194 strains(7.01%)of Acinetobacter baumannii(AB),among which 125 strains(64.43%)were CR-AB;there were 291 strains(10.51%)of Staphylococcus aureus,among which 79 strains(27.15%)of methicillin-resistant Staphylococcus aureus(MRSA)were detected;78 strains(2.82%)of Enterococcus faecalis were detected,and vancomycin-resistant enterococcus(VRE)was not detected.The first five MDROs were CR-AB,CR-PA,MRSA,CR-KP,and CR-ECO.The top five departments with the highest MDRO detection rate in 2022 were the ICU(37.44%),the Pulmonology Department(ward 13;31.03%),the Department of Rehabilitation(ward 5;6.67%),the Department of Neurosurgery(ward 11;4.62%),and the Department of General Surgery(ward 10;3.59 The resistance rate of antibacterial drugs is divided into four levels for early warning:30%to 40%,41%to 50%,51%to 75%,and 75%or more.Conclusion:Our hospital should strengthen the monitoring of antimicrobial resistance warning related to MDRO and the abuse of antimicrobial drugs.Based on the results of drug sensitivity and antimicrobial resistance warning,the use of antibiotics should be standardized in clinical practice to reduce nosocomial infection。

Clinical Distribution and Drug Resistance of Acinetobacter baumannii in a Hospital from 2019 to 2021

Objective:To analyze the clinical distribution and drug resistance of Acinetobacter baumannii(AB)and provide reference for the treatment of AB infection.Methods:AB isolated from clinical specimens of Huaihua First People’s Hospital from 2019 to 2021 were collected and identified by VITEK 2 Compact,an automated microbial identification and susceptibility testing system,in which drug sensitivity test was also performed.Excel was used for statistical analysis.Results:Among the 1,311 AB strains,81.16%(1,064 strains)were from sputum samples,and the departments with the highest detections rates of AB were neurosurgery(24.33%),intensive care(15.48%)and infectious disease(11.44%).The drug sensitivity test showed that the resistance rate of 1,311 AB strains to compound sulfamethoxazole and amikacin was 28.38%and 20.54%,respectively,and the resistance rate to 10 other kinds of common antibiotics was more than 40%.Conclusion:The 1,311 AB strains isolated were widely distributed in clinical settings and had strong resistance to commonly used antibiotics.Therefore,it is necessary to strengthen the monitoring of pathogens and drug resistance,formulate reasonable and effective infection control measures,and ensure that antibiotics are used in a reasonable manner.

Risk factors and antibiotic resistance of pneumonia caused by multidrug resistant Acinetobacter baumannii in pediatric intensive care unit

With beta-lactam drugs and immunosuppressants widely used, the infection caused by Acinetobacter baumannfi （Ab） has become more and more serious with multidrug resistant Acinetobacter baumannfi （MDRAb） emerging and worsening rapidly. Compared with other patients, the incidence and multidrug resistance of MDRAb are higher in children in pediatric intensive care unit （PICU） because of immune deficiency, severe basic diseases, prolonged hospitalization and invasive operations. Hence it is significant to study the epidemiology and changes of antibacterial susceptibility in order to reduce the incidence of MDRAb in children. A total 115 patients with MDRAb pneumonia and 45 patients with negative MDRAb （NMDRAb） pneumonia who had been treated from January 2009 to August 2011 were studied retrospectively at the PICU of Wuhan Children＇s Hospital. Clinical data were analyzed with univariate and multivariate Logistic regression. In 176 clinical strains of Acinetobacter baumannfi isolated, there were 128 strains of MDRAb, accounting for 72.73%. Drug susceptibility tests showed that the resistance rates of 13-1actam antibiotics were more than 70% except for cefoperazone sulbactam. The rates to carbapenems were higher than 90%. They were significantly higher than those of NMDRAb. Amikacin, levofloxacin, ciprofloxacin and minocycline had the lowest drug-resistance rates （〈20%）. Multivariate Logistic regression revealed that ICU stay, the time of mechanical ventilation, anemia, hypoproteinemia and the use of carbapenems were independent risk factors for MDRAb pneumonia. MDRAb is an important opportunistic pathogen to pneumonia in PICU, and its drug-resistance is severe. It increases significantly the mortality of patients. It is important to take the effective prevention measures for controlling it.

Patient Demographics and Characteristics of Infection with Carbapenem-Resistant <i>Acinetobacter baumannii</i>in a Teaching Hospital from the United States

A characterization of the clinical demographic features of patients with infection caused Acinetobacter baumannii, and the antibiotyping of the isolates recovered from these patients was undertaken, with a special reference to carbapenem-resistant variants, and their risk factors. This study was conducted retrospectively from January 2010 to March 2011 at a 616-bed tertiary care university hospital. Sixty-four patients were identified. Clinical and microbiological data were analyzed for risk factors and demographic features to derive relative risk and odds ratio. We identified 100 A. baumannii from 64 patients during 15 months period. Significant risk factors were working age (18 - 60 years), male gender, hospital stay (>1 week but Pseudomonas aeruginosa, and Klebsiella pneumoniae were the significant co-infecting agents. The antibiogram demonstrated multidrug resistance in a majority of the isolates. Relative risk associated with ventilator, diabetes, and surgery was higher in repeat isolates than in first isolates and were multidrug resistant. Repeat isolates were more resistant that the first isolates to most anti-acinetobacter agents, but the overall crude mortality was not significant during this study period, and couldn’t correlated to the choice of treatment. In conclusion, a resistance against all clinically used carbapenems, and colistin is rapidly increasing in repeat isolates of A. baumannii;leaves narrow therapeutic options to treat multidrug-resistant and pandrug-resistant A. baumannii infection. For the first time we report rising incidence of colistin resistance by 20 percent in repeat isolates, and is worrisome for healthcare centers. A combination therapy should be adopted to treat such infection to avoid the emergence of colistin-resistant phenotypes in the United States.

Postoperative multidrug-resistant Acinetobacter baumannii meningitis successfully treated with intravenous doxycycline and intraventricular gentamicin: A case report

BACKGROUND Multidrug-resistant Acinetobacter baumannii(MDRAB) has emerged as an increasingly important pathogen that causes nosocomial meningitis. However,MDRAB-associated nosocomial meningitis is rarely reported in children.CASE SUMMARY We report the case of a 1-year-old girl with a choroid plexus papilloma, who developed postoperative nosocomial meningitis due to MDRAB. The bacterial strain was sensitive only to tigecycline and colistin, and showed varying degrees of resistance to penicillin, amikacin, ceftriaxone, cefixime, cefotaxime,ciprofloxacin, levofloxacin, gentamicin, meropenem, imipenem, and tobramycin.She was cured with intravenous doxycycline and intraventricular gentamicin treatment.CONCLUSION Doxycycline and gentamicin were shown to be effective and safe in the treatment of a pediatric case of MDRAB meningitis.

Risk factors and outcomes of imipenem-resistant Acinetobacter bloodstream infection in North-eastern Malaysia

Objective:To determine the risk factors and outcomes of imipenem-resistant Acinetobacter baumannii(IRAB) bloodstream infection(BSI) cases,since there is very little publication on Aeinetobacter baumannii infections from Malaysia.Methods:A cross sectional study of 41 cases(73.2%) of imipenem-sensitive Acinetobacter baumanii(ISAB) and 15 cases(26.8%) of IRAB was conducted in a teaching hospital which was located at North-Eastern state of Malaysia.Results:There was no independent risk factor for IRAB BSI identified but IRAB BSI was significantly associated with longer bacteraemic days[OR 1.23(95%CI 1.01,1.50)].Although prior use of carbepenems and cephalosporin were higher among IRAB than ISAB group,statistically they were not significant.There was no significant difference in term of outcomes between the two groups.Conclusions:Although statistically not significant,this analysis compliments previous publication highlighting the importance of appropriate empiric antibiotic usage in hospital especially carbepenems and need further evaluation with bigger subjects.

Molecular Detection of Carbapenemase Genes in Extensive Drug Resistant Acinetobacter baumannii Clinical Isolates from ICU Patients, Khartoum

Background: The emergence of carbapenemase producing Acinetobacter baumannii is increasingly reported nowadays and constitutes a major problem to the intensive care unit (ICU) patients with notable extensive-drug resistance ability. The study investigates carbapenemase producing A. baumannii strains exhibiting an extensively drug-resistant (XDR) phenotype, isolated from ICU patients in Khartoum. Methods: A total of 100 nonduplicate Gram-negative coccobacilli strains were obtained from microbiology laboratory of ICU patients’ clinical isolates. Molecular identification of A. baumannii was performed by targeting 16S rRNA gene using specifically designed primers. Then, XDR strains were determined by susceptibility testing (disc diffusion). For detection of carbapenemase genes Polymerase chain reaction (PCR) was carried out. Result: Of 100 ICU clinical isolates, 38 (38.0%) was confirmed A. baumannii strains, those strains showed 100% carbapenem resistance and 60.5% extensive drug resistance to the antibiotics tested. The frequency of carbapenemase producer was 57.9% (22/38) of carbapenem resistance A. baumannii (CRAB). The most common carbapenemase associated with resistance was blaOXA gene followed by blaNDM and blaGES A. baumannii isolates. The co-occurrence of blaOXA-48-like and blaNDM, blaOXA-23-like and blaOXA-51, and blaNDM-1 and blaOXA-51 was detected in 22.7%, 18.2% strains and 4.5% respectively. A unique characteristic of our findings was the coharbouring of the genes blaNDM-1, blaOXA-23-like, blaOXA-51 and blaOXA-143 in 9.1% strains (2/22), and this was the first report in the Khartoum city, Sudan. Conclusion: We have demonstrated for the first time a high prevalence of XDR-carbapenemase producing A. baumannii clinical isolates from ICU patients in Khartoum. Also an emergent blaOXA-143 was reported as High-Risk Clones. This highlights the routine mentoring of XDR-carbapenemase producing A. baumannii to avoid clone dissemination in our region hospitals.

An Extensively Drug Resistant Acinetobacter baumannii from Soft Tissue Isolated in a Hospital in Senegal

Emerging and rapidly spreading multidrug resistant bacteria constitute a rising public health concern worldwide. Acinetobacter baumannii is one of these bacteria that cause different infections including pneumonia, bacteremia, meningitis, soft-tissue, and urinary tract infections, and are associated with high mortality and economic burden. We present a case of a 43-year-old woman, admitted at the department of orthopedics, regional hospital of Ourossogui, North-East of Senegal for soft-tissue injuries. Initially diagnosed with Yersinia pestis infection, the patient was well managed before being released. Supplementary sampling for confirmatory tests allowed the detection of an extensively drug-resistant Acinetobacter baumannii clone.

Antimicrobial Susceptibility of Multidrug-Resistant <i>Acinetobacter baumanii</i>in a Teaching Hospital: A Two-Year Observation

Multidrug-resistant (MDR) Acinetobacter baumanii (A. baumanii) caused hospital acquired infection, typically in critical-ill patients with medical devices. This is a retrospective descriptive study on epidemiology and microbiology data to determine the antimicrobial susceptibility pattern of MDR-Acinetobacter baumanii isolates from a teaching hospital in Tangerang, Indonesia from Januari 2013 to December 2014. A total of 84 A. baumanii were collected. Patients suffering from respiratory tract infection had the highest number (41.7%) of A. baumanii isolate. There were 39 (46.6%) patients admitted in critical care. A. baumanii isolates in this study mostly were multidrug-resistant organisms with low susceptibility level to 11 antibiotic tested, 44% - 69% in 2013 and 26% - 67% in 2014. A high susceptibility level was observed to amikacin (80% and 79% in 2013, 2014 consecutively) and trimethoprim-sulfamethoxazole (73% and 72% in 2013, 2014 consecutively). A. baumanii is a hospital acquired pathogen in critically-ill patients. The susceptibility pattern of this study result showed MDR organism. There was a sharp decrease of susceptibility in all antibiotics studied from 2013 to 2014 except amikacin and trimethoprim-sulfamethoxazole.

Control of multidrug-resistant planktonic Acinetobacter baumannii:biocidal efficacy study by atmospheric-pressure air plasma

In this research,an atmospheric-pressure air plasma is used to inactivate the multidrug-resistant Acinetobacter baumannii in liquid.The efficacy of the air plasma on bacterial deactivation and the cytobiological variations after the plasma treatment are investigated.According to colony forming units,nearly all the bacteria（6-log） are inactivated after 10 min of air plasma treatment.However,7% of the bacteria enter a viable but non-culturable state detected by the resazurin based assay during the same period of plasma exposure.Meanwhile,86% of the bacteria lose their membrane integrity in the light of SYTO 9/PI staining assay.The morphological changes in the cells are examined by scanning electron microscopy and bacteria with morphological changes are rare after plasma exposure in the liquid.The concentrations of the long-living RS,such as H2O2,NO3^- and O3,in liquid induced by plasma treatment are measured,and they increase with plasma treatment time.The changes of the intracellular ROS may be related to cell death,which may be attributed to oxidative stress and other damage effects induced by RS plasma generated in liquid.The rapid and effective bacteria inactivation may stem from the RS in the liquid generated by plasma and air plasmas may become a valuable therapy in the treatment of infected wounds.

Antimicrobial resistance in Acinetobacter baumannii : From bench to bedside

Acinetobacter baumannii(A. baumannii) is undoubtedly one of the most successful pathogens in the modern healthcare system. With invasive procedures, antibiotic use and immunocompromised hosts increasing in recent years, A. baumannii has become endemic in hospitals due to its versatile genetic machinery, which allows it to quickly evolve resistance factors, and to its remarkable ability to tolerate harsh environments. Infections and outbreaks caused by multidrugresistant A. baumannii(MDRAB) are prevalent and have been reported worldwide over the past twenty or more years. To address this problem effectively, knowledge of species identification, typing methods, clinical manifestations, risk factors, and virulence factors is essential. The global epidemiology of MDRAB is monitored by persistent surveillance programs. Because few effective antibiotics are available, clinicians often face serious challenges when treating patients with MDRAB. Therefore, a deep understanding of the resistance mechanisms used by MDRAB can shed light on two possible strategies to combat the dissemination of antimicrobial resistance: stringent infection control and antibiotic treatments, of which colistin-based combination therapy is the mainstream strategy. However, due to the current unsatisfying therapeutic outcomes, there is a great need to develop and evaluate the efficacy of new antibiotics and to understand the role of other potential alternatives, such as antimicrobial peptides, in the treatment of MDRAB infections.

Biofilm formation in clinical isolates of nosocomial Acinetobacter baumannii and its relationship with multidrug resistance

Objective: To check biofilm formation by Acinetobacter baumannii(A. baumannii)clinical isolates and show their susceptibility to different antibiotics and investigate a possible link between establishment of biofilm and multidrug resistance.Methods: This study was performed on clinical samples collected from patients with nosocomial infections in three hospitals of Tehran. Samples were initially screened by culture and biochemical tests for the presence of different species of Acinetobacter. Identifications were further confirmed by PCR assays. Their susceptibilities to 11 antibiotics of different classes were determined by disc diffusion method according to Clinical and Laboratory Standards Institute guidelines. The ability to produce biofilm was investigated using methods: culture on Congo red agar, microtiter plate, and test tube method.Results: From the overall clinical samples, 156 specimens were confirmed to contain A. baumannii. The bacteria were highly resistant to most antibiotics except polymyxin B.Of these isolates, 10.26% were able to produce biofilms as shown on Congo red agar.However, the percentage of bacteria with positive biofilm in test tube, standard microtiter plate, and modified microtiter plate assays were 48.72%, 66.66%, and 73.72%, respectively. At least 92% of the biofilm forming isolates were multidrug resistant.Conclusions: Since most of the multidrug resistant strains produce biofilm, it seems necessary to provide continuous monitoring and determination of antibiotic susceptibility of clinical A. baumannii. This would help to select the most appropriate antibiotic for treatment.

Antibiotic resistance and carriage class 1 and 2 integrons in clinical isolates of Acinetobacter baumannii from Tehran,Iran

Objective:To investigate antibiotic resistance and carriage class 1 and 2 integrons in clinical isolates of Acinetobacter baumannii(A.baumannii)from Tehran,Iran.Methods:Antimicrobial susceptibility testing was performed according to the Clinical and Laboratory Standards Institute.The presence of integrons was investigated by PCR using specific primers.Results:Among isolated A.baumannii strains,82%were multidrug resistant,27 samples(54%)were resistant to three or more than three antibiotics and 16 samples(32%)showed resistance to two antibiotics.Integrons were detected from 44 of 50 isolates(88%),with classes 1 and 2 being observed in 42%(21/50)and 82%(41/50)of isolates,respectively.Integron-positive A.baumannii isolates showed higher antibiotic resistance than integron-negative isolates and all showed a multidrug-resistant phenotype.Conclusions:Our findings show that classes 1 and 2 integrons,and especially classes 2 integrons are widely disseminated among A.baumannii strains isolated from Tehran and these structures are playing a major role in the acquisition of multidrug resistance in these strains.So monitoring of drug resistance with investigating carriage class 1 and 2 integrons is very important to plan specific infection control measures due to multidrug resistance A.baumannii in Iran hospitals.

Antimicrobial activity of green tea extract against isolates of methicillin-resistant Staphylococcus aureus and multi-drug resistant Pseudomonas aeruginosa

Objective:To evaluate antibacterial activity of the Indonesian water soluble green tea extract,Camellia sinensis,against clinical isolates of methicillin-resistantStaphylococcus aureus (S.aureus)(MRSA)and multi-drug resistant Pseudomonas aeruginosa(MDR-P.aeruginosa).Methods:Antimicrobial activity of green tea extract was determined by the disc diffusion method and the minimum inhibitory concentration(MIC)was determined by the twofold serial broth dilutions method.The tested bacteria using in this study were the standard strains and multi-drug resistant clinical isolates of S.aureus and P.aeruginosa,obtained from Laboratory of Clinical Microbiology,Faculty of Medicine,University of Indonesia.Results:The results showed that the inhibition zone diameter of green tea extracts forS.aureus ATCC 25923 and MRSA were(18.970依0.287)mm,and(19.130依0.250)mm respectively.While the inhibition zone diameter forP.aeruginosa ATCC 27853 and MDR-P.aeruginosawere(17.550依0.393)mm and(17.670依0.398)mm respectively.The MIC of green tea extracts againstS.aureus ATCC 25923 and MRSA were 400μg/mL and 400μg/mL,respectively,whereas the MIC for P.aeruginosa ATCC 27853 and MDR-P.aeruginosawere 800μg/mL,and 800μg/mL,respectively.Conclusions:Camellia sinensisleaves extract could be useful in combating emerging drug-resistance caused by MRSA andP.aeruginosa.

Cytotoxic and antibacterial substances against multi-drug resistant pathogens from marine sponge symbiont:Citrinin,a secondary metabolite of Penicillium sp.

Objective:To Isolate,purify,characterize,and evaluate the bioaclive compounds from the sponge-derived fungus Penicillium sp.FF001 and to elucidate its structure.Methods:The fungal strain FF001 with an interesting bioactivity profile was isolated from a marine Fijian sponge Melophlus sp.Based on conidiophores aggregation,conidia development and mycelia morphological characteristics,the isolate FF001 was classically identified as a Penicillium sp.The bioactive compound was identified using various spectral analysis of UV,high resolution electrospray ionization mass spectra,1H and 13C NMR spectral data.Further minimum inhibitory concentrations(MICs)assay and brine shrimp cytotoxicity assay were also carried out to evaluate the biological properties of the purified compound.Results:Bioassay guided fractionation of the EtOAc extract of a static culture of this Penicillium sp.by different chromatographic methods led the isolation of an antibacterial,anticryptococcal and cytotoxic active compound,which was identified as citrinin(1).Further,citrinin(1)is reported for its potent antibacterial activity against methicillin-resistant Staphylococcus aureus(S.aureus),rifampicin-resistant 5.aureus,wild type S.aureus and vancomycin-resistant Enterococcus faecium showed MICs of 3.90,0.97,1.95 and7.81μg/mL,respectively.Further citrinin(1)displayed significant activity against the pathogenic yeast Cryptococcus neoformans(MIC 3.90μg/mL),and exhibited cytotoxicity against brine shrimp larvae LD_(50)of 96μg/mL.Conclusions:Citrinin(1)is reported from sponge associated Penicillium sp.from this study and for its strong antibacterial activity against multi-drug resistant human pathogens including cytotoxicity against brine shrimp larvae,which indicated that sponge associated Penicillium spp.are promising sources of natural bioactive metabolites.

<i>In Vitro</i>Antibacterial Activity of Flavonoid Extracts of Two Selected Libyan Algae against Multi-Drug Resistant Bacteria Isolated from Food Products

This study aimed to evaluate the antibacterial activity of flavonoids extracted from two Libyan brown algae namely Cystoseira compressa and Padina pavonica using microwave-assisted extraction method against pathogenic bacteria isolated from meat, meat products, milk and dairy products (Staphylococcus aureus subsp. aureus (5 isolates), Bacillus cereus (3 isolates), Bacillus pumilus (1 isolate), Salmonella enterica subsp. enteric (4 isolates) and Enterohaemor-rhagic Escherichia coli O157 (EHEC O157) (4 isolates)). All of these isolates were muti-drug resistant with high MAR index. The results showed that C. compressa extract exhibited better and stronger antibacterial activities against the seventeen tested isolates with inhibition zones diameter ranged from 14 - 22 mm compared to P. pavonica extract which showed positive effect against 9 isolates with low inhibition zone ranged from 11 - 16.5 mm. Flavonoids extracted from C. compressa also displayed the best spectrum of bactericidal effect with a ratio MBC/MIC ≤ 4 obtained on all susceptible tested bacterial strains. Flavonoids and proanthocyanidins significantly contributed to the antibacterial properties. The mode of action of these active extracts is under investigation.

Antibacterial resistance patterns of Acinetobacter baumannii complex:The results of Isfahan Antimicrobial Resistance Surveillance-1 Program

Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 to March 2018 in three referral hospitals in Isfahan, Iran. All A. baumannii complex strains isolated from different clinical samples were identified by conventional phenotypic methods and antibiotic susceptibility pattern was detected. After the clinical investigation, contaminated samples were excluded and the source(hospital/community) and site of the infection were determined. Data on antibiotic susceptibility testing were extracted from WHONET software and analysis was done with SPSS.Results: From 254 patients who had confirmed A. baumannii complex infection, 158(62.20%) cases were male, 27(10.63%) were less than 20 years old, 172(67.72%) had healthcare-associated infections and 96(37.79%) were admitted in intensive care units. The most frequent infection was bloodstream infections(111, 43.70%). Our results showed that most of the isolates were resistant to most of the antibiotics(more than 75.00%) and a lower rate of non-susceptibility was observed against minocycline(20, 44.44%) and colistin(0%). The rate of multidrug-resistant isolates was 88.97%. There was no significant difference between resistance of A. baumannii complex isolates according to age. However, the resistance to amikacin and minocycline and the rate of multidrug resistance(MDR) were significantly different between males and females. In patients with healthcare associated infection(HAI), MDR isolates were significantly different regarding admission in ICU ward. Resistance to levofloxacin and ciprofloxacin were lower in isolates from patients with bloodstream infections in comparison to other diagnoses.Conclusions: In our study, a high level of antibiotic resistance was detected in both community-acquired and healthcare-associated A. baumannii complex infections. Appropriate antibiotic prescription in a clinical setting is an essential need for the control and prevention of A. baumannii resistant infections.