Frequency, risk factors, and antibiogram of Acinetobacter species isolated from various clinical samples in a tertiary care hospital in Odisha, India

Antimicrobial resistance profile and associated factors of hospital-acquired gram-negative bacterial pathogens among hospitalized patients in northeast Ethiopia

BACKGROUND

Antimicrobial resistance is a major global public health issue. Infections caused by resistant species are associated with higher mortality rates, longer hospital stays, medication failure, and rising medical costs. The World Health Organisation has declared multidrug resistance-associated infections as an epidemic of public health concern.

OBJECTIVE

This study aimed to evaluate the antimicrobial resistance profile and associated factors of hospital-acquired Gram-negative bacterial pathogens among hospitalized patients in Northeast Ethiopia.

MATERIALS AND METHODS

A health facility-based cross-sectional study was conducted among hospitalized patients from March 2021 to February 2022. About 810 clinical specimens were collected, transported, and processed from admitted patients following the standard bacteriological procedures. The clinical samples were inoculated onto blood agar, MacConkey agar, and chocolate agar. Furthermore, the species identification was done using gram reactions, colony morphology, and color and biochemical tests. Antimicrobial susceptibility tests, extended-spectrum beta-lactamase, and carbapenemase production were performed as per the clinical laboratory standard institute guidelines. For analysis, the information was entered into Epi-data and exported to SPSS. A P value of < 0.05 with a 95% confidence interval was considered as a statistically significant association.

RESULTS

Out of 810 clinical specimens, 285/810 (35.2%) developed bacterial infections. From the isolated bacteria, E. coli was the predominant bacteria accounting for 78/285 (27.4%) followed by K. pneumoniae, 69/285(24.42%), whereas P. vulgaris accounted for the least, 7/285 (2.5%). Overall, 132/285 (46.3%) and 99/285 (34.7%) of culture-positive patients were infected by extended-spectrum beta-lactamase and carbapenemase-producing bacteria. The overall multidrug resistance rate of the isolated bacteria was 89.4%. The highest antibiotic resistance rates were detected for doxycycline (92.9%), amoxicillin-clavulanic acid (83.9%), and ampicillin (93%). The least antibiotic resistance rate was observed for meropenem at 41.1% and amikacin at 1.7%, respectively.

CONCLUSIONS AND RECOMMENDATIONS

In the study area, significant health concerns include a range of hospital-acquired bacterial infections associated with elevated rates of multidrug resistance, Extended-spectrum beta-lactamase (ESBL), and carbapenemase-producing bacterial pathogens. Consequently, it is recommended to conduct drug-susceptibility testing of isolates and molecular detection at a national level to optimize antibiotic usage for treating prevalent bacterial infections in this area.

Diversity of resistant determinants, virulence factors, and mobile genetic elements in Acinetobacter baumannii from India: A comprehensive in silico genome analysis

Introduction

The frequency of infections associated with multidrug resistant A. baumannii has risen substantially in India. The use of next-generation sequencing (NGS) techniques combined with comparative genomics has great potential for tracking, monitoring, and ultimately controlling the spread of this troublesome pathogen. Here, we investigated the whole genome sequences of 47 A. baumannii from India.

Methods

In brief, A. baumannii genomes were analyzed for the presence of antibiotic resistance genes (ARGs), virulence factors genes (VFGs), and mobile genetic elements (MGEs) using various in silico tools. The AbaR-type resistance islands (AbaRIs) were detected by examining the genetic environment of the chromosomal comM gene. Multilocus sequence types were determined using the Pasteur scheme. The eBURST and whole genome SNPs-based phylogenetic analysis were performed to analyze genetic diversity between A. baumannii genomes.

Results and discussion

A larger number of A. baumannii isolates belonging to the ST2 genotype was observed. The SNPs-based phylogenetic analysis showed a diversity between compared genomes. The predicted resistome showed the presence of intrinsic and acquired ARGs. The presence of plasmids, insertion sequences, and resistance islands carrying putative ARGs conferring resistance to antibiotics, quaternary ammonium compounds, and heavy metals was predicted in 43 (91%) genomes. The presence of putative VFGs related to adherence, biofilm formation and iron uptake was observed in the study. Overall, the comprehensive genome analysis in this study provides an essential insight into the resistome, virulome and mobilome of A. baumannii isolates from India.

Emergence of High Prevalence of Extended-Spectrum Beta-Lactamase and Carbapenemase Producing Acinetobacter Species and Pseudomonas aeruginosa Among Hospitalized Patients at Dessie Comprehensive Specialized Hospital, North-East Ethiopia

Background

The emergence of extended spectrum beta lactamase and carbapenemase production of Acinetobacter and Pseudomonas aeruginosa is a great concern and major cause of nosocomial infections due to its ability to production of extended spectrum beta lactamase and carbapenemase enzymes.

Objective

To assess Emergence of high prevalence of extended-spectrum beta-lactamase and Carbapenemase producing Acinetobacter species and Pseudomonas aeruginosa among hospitalized patients at Dessie Comprehensive Specialized Hospital, North-East Ethiopia.

Materials and Methods

A hospital-based cross-sectional study was conducted from February–August 2021 at Dessie Referral Hospital in the North eastern Ethiopia. A total of 423 clinical samples taken from admitted patients. Clinical specimens were collected aseptically and inoculated on blood agar and MacConkey agar media. Antimicrobial susceptibility test, ESBL and carbapenemase production were performed as CLSI guideline. The data were entered into the Epi-data and imported to Statistical Package for Social Science version 25. P value of <0.05 with odds ratio and 95% confidence interval was considered as statistically significant.

Results

Out of 423 clinical specimens 17.7% (75/423) were culture positive nosocomial infection. The proportions of nosocomial infection were higher in blood stream followed by wound infection which accounted 24.6%, 20.8%, respectively. Overall, 32/75 (42.7%) and 19/75 (25.3%) patients had infection with ESBL and CP producing bacterial infection. P. aeruginosa was the most predominant isolated bacteria 46/75 (52.9%). The overall multidrug resistance rate of the isolated bacteria was 88% (66/75). The majority of highest resistance rate was Piperacillin tazobactam 50 (66.7%) and Aztreonam 26 (56.5%), respectively, while least resistance rate was Amikacin 27 (36%).

Conclusion

The incidence rates of ESBL, carbapenemase production and antimicrobial resistant Acinetobacter species and P. aeruginosa infections are high. Therefore, treatment should be based on culture and antimicrobial test result and minimize the use of antibiotics empirically.

Identification, Speciation and Antibiogram along with Detection of Metallo Beta-lactamase Production in Acinetobacter Isolated from Clinical Samples in a Tertiary Care Hospital

Acinetobacter species are gram negative non fermenters, which are important nosocomial pathogens involved in various outbreaks in hospitals due to widespread resistance to majority antibiotics. The aim of this study is to speciate Acinetobacter isolated from clinical samples, to assess the antibiotic sensitivity pattern and to detect the production of metallo-β-lactamase by double disc synergy test. The study was conducted in the department of microbiology, A. J Institute of Medical Sciences. All clinical samples were subjected to gram stain & cultured; the Acinetobacter isolates obtained were subjected to antibiogram. Those isolates that showed Imipenem resistant were further tested for production of metallo-β-lactamase by double disc synergy test. Out of 6625 culture positive isolates, 414 (36.1%) were identified biochemically to belong to Acinetobacter species. Of the 414 cases, 393 (94.9%) were further identified to be Acinetobacter baumannii and the remaining 21 (5.1%) to be Acinetobacter lwoffi. Acinetobacter lwoffii showed 100% sensitivity to all the drugs. Of the 393 Acinetobacter baumannii isolates 109 (27.7%) showed resistant to Imipenem. Out of these 109 isolates, 65 (59.63%) were positive for metallo-β-lactamase production by double disk synergy test. The speciation is highly demanding and laborious but it’s important to be demonstrated due to difference in the antibiotic susceptibility pattern. Carbapenem resistant Acinetobacter nosocomial strains in ICUs are detected to be more resistant to antibiotics. As shown in this study the metallo-β-lactamase producing A.baumannii isolates were 59.63% and therapeutic options were limited. Therefore early identification of metallo-β-lactamase producers is of great importance to start appropriate treatment and to control the spread.

Occurrence of bla genes encoding carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter baumannii from Intensive Care Unit in a tertiary care hospital

CONTEXT:

ICU shows increasing incidence of infection associated with the use of invasive procedures for the diagnostic purpose as well as the indiscriminate use of antibiotics. Pseudomonas aeruginosa and Acinetobacter species are “very successful” pathogen and the emergence of the Metallo-β-Lactamases (MBL) is becoming a therapeutic challenge.

AIMS:

To isolate the Nonfermenting Gram negative bacilli from the ICU samples. To identify the metallo betalactamase producers and to detect the bla gene presence among the Pseudomonas aeruginosa and Acinetobacter baumannii.

SETTINGS AND DESIGN:

The Nonfermenting Gram negative bacilli isolates from the ICU samples were taken over for 5 years (2009-2014) in a tertiary care hospital.

METHODS AND MATERIALS:

The isolates of Pseudomonas species and Acinetobacter species were confirmed by API analyser and processed according to standard procedures. Detection of the MBL producers were done by E strip method and subjected for bla gene detection by PCR method.

RESULTS:

In our study a total of 195 isolates of NFGNB were obtained from various ICU. Of these MBL producers, 26 % were Pseudomonas aeruginosa and 25 % were Acinetobacter baumannii. The subtypes of bla_VIM MBL producing P.aeruginosa were 26%. The predominant gene coding for MBL activity in A.baumannii were found to be bla_OXA gene 11.9%. The gene accession numbers were KF975367, KF975372.

CONCLUSIONS:

We have to control the development and dissemination of these superbugs among the ICU's.

Antimicrobial susceptibility pattern of Acinetobacter isolates from patients in Kenyatta National Hospital, Nairobi, Kenya

Introduction

Infection due to multidrug-resistant microorganisms is a growing threat in healthcare settings. Acinetobacter species specifically A. baumannii is increasingly becoming resistant to most antimicrobial agents recommended for treatment. This study aimed to determine the antimicrobial susceptibility pattern of Acinetobacter species isolated from patients in Kenyatta National Hospital.

Methods

We conducted a retrospective study based on VITEK 2 (BioMérieux) electronic records capturing identification and antimicrobial susceptibility of Acinetobacter isolates from patient samples analyzed between 2013 and 2015 at Kenyatta National Hospital microbiology laboratory. Generated data were analyzed using WHONET and SPSS.

Results

A total of 590 Acinetobacter isolates were analyzed. 85% of the isolates tested were multi-drug resistant (MDR). Among the 590 isolates, 273 (46%) were from tracheal aspirates and 285 (48%) from the critical care unit. A. baumannii was the most frequently isolated species with high susceptibility to amikacin (77%) and poor susceptibility to ciprofloxacin (69-76%), tobramycin (37%) and meropenem (27%). Both A. lwoffii and A. haemolyticus had high susceptibility to amikacin (80-100%) and meropenem (75-100%).

Conclusion

A. baumannii is resistant to commonly administered antibiotics. There is need for continuous antimicrobial resistance surveillance especially in health care facilities and strengthening of antibiotic stewardship programmes which will contribute to enhancement of infection control policies.

Emergence and characterization of nosocomial multidrug-resistant and extensively drug-resistant Acinetobacter baumannii isolates in Tehran, Iran

RATIONALE

Acinetobacter baumannii is one of the antibiotic-resistant superbugs that threatens hospitalized patients. Emergence and spread of the multidrug-resistant (MDR) and extensively drug-resistant (XDR) clones cause erratic outbreaks following environmental contamination of hospital settings.

OBJECTIVE

The present study intended to characterize the antimicrobial resistant profiles and the genotypes of clinical and environmental isolates of A. baumannii as a result of dissemination of resistant strains.

METHODS

Clinical and environmental isolates of A. baumannii were obtained from patients, staff, and environment of an educational hospital in Tehran. Antimicrobial susceptibility testing was carried out using the disk diffusion and E-test methods. Multiplex PCR was performed for detection of OXA-type genes (bla_OXA-23-like, bla_OXA-24-like, bla_OXA-58-like, and bla_OXA-51-like). Genotypic relatedness of the isolates was achieved using repetitive extragenic palindromic element PCR (Rep-PCR) technique.

RESULTS

All the isolates were found to be susceptible to colistin and most of them (77%) were non-susceptible to tigecycline. A majority of the clinical and environmental isolates (97%) were considered as MDR strains and 41% as XDR. In multiplex detection, bla_OXA-23-like was found in 54% of the isolates, which was the most frequent OXA-type gene. In addition, the frequency of the carbapenem-resistant A. baumannii (CRAB) was observed to be high (96%). In addition, molecular typing showed different Rep patterns of clinical isolates and clonal spread of environmental isolates.

CONCLUSION

The present study highlights the circulation of drug-resistant A. baumannii strains in different wards of hospitals principally in intensive care unit (ICU) as a nosocomial pathogen due to unwise managements.

Analysis of clinical and microbiological data on Acinetobacter baumannii strains assist the preauthorization of antibiotics at the patient level for an effective antibiotic stewardship program

Drug resistant Acinetobacter baumannii (A. baumannii) poses serious treatment challenges and is on the rise worldwide. The Infectious Diseases Society of America/Society for Healthcare Epidemiology of America recommends preauthorization of antibiotics to ensure successful antibiotic stewardship programs (ASWPs). This study estimates and analyzes the microbiological and clinical characteristics of A. baumanii strains with differentiating criteria for sepsis versus colonization, in order to support preauthorization and assist ASWPs at the patient level. A retrospective observational study was performed from 2008 to 2014. The clinical and microbiological characteristics of A. baumannii strains were correlated to assess pathogenic status and antibiotic resistance patterns. A flow chart was produced to differentiate between sepsis and colonization amongst patient groups. A. baumannii was cultured in 2656 cases, with a prevalence of 0.9-2.4% during 7 years study periods. There was a statistically significant difference between the sepsis and colonization groups (P=0.02). Sepsis accounted for 37-51% of A. baumanii isolates and colonisation for 49-63% (P=<0.01). Multidrug resistant (MDR), extensive drug resistant (XDR) and pandrug resistant (PDR) A. baumannii was detected in 53-60%, 1-19% and 1% of cultures in the sepsis group, and 75%, 8-23% and 1% in the colonized group. There was a high percentage of polymicrobial infection in the sepsis group and pure growth was not always significant for sepsis. Cases of MDR and XDR A. baumannii increased over the seven-year study, while PDR strains emerged. For a successful ASWP, both clinical and microbiological information should be interpreted when establishing preauthorization/decision to treat.

Bacteriological profile and antibiotic susceptibility patterns of clinical isolates in a tertiary care cancer center

Introduction:

This increased risk of bacterial infections in the cancer patient is further compounded by the rising trends of antibiotic resistance in commonly implicated organisms. In the Indian setting this is particularly true in case of Gram negative bacilli such as Escherichia coli, Klebsiella pneumoniae and Acinetobacter spp. Increasing resistance among Gram positive organisms is also a matter of concern. The aim of this study was to document the common organisms isolated from bacterial infections in cancer patients and describe their antibiotic susceptibilities.

Methods:

We conducted a 6 month study of all isolates from blood, urine, skin/soft tissue and respiratory samples of patients received from medical and surgical oncology units in our hospital. All samples were processed as per standard microbiology laboratory operating procedures. Isolates were identified to species level and susceptibility tests were performed as per Clinical Laboratory Standards Institute (CLSI) guidelines -2012.

Results:

A total of 285 specimens from medical oncology (114) and surgical oncology services (171) were cultured. Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Acinetobacter spp. were most commonly encountered. More than half of the Acinetobacter strains were resistant to carbapenems. Resistance in Klebsiella pneumoniae to cephalosporins, fluoroquinolones and carbapenems was >50%. Of the Staphylococcus aureus isolates 41.67% were methicillin resistant.

Conclusion:

There is, in general, a high level of antibiotic resistance among gram negative bacilli, particularly E. coli, Klebsiella pneumoniae and Acinetobacter spp. Resistance among Gram positives is not as acute, although the MRSA incidence is increasing.

A prospective evaluation of synergistic effect of sulbactam and tazobactam combination with meropenem or colistin against multidrug resistant Acinetobacter baumannii

The present study evaluates the synergistic effect of sulbactam/tazobactam in combination with meropenem or colistin against multidrug resistant (MDR) Acinetobacter baumannii isolated from hospitalized patients from a tertiary care hospital in Saudi Arabia. During the study period, 54 multidrug and carbapenem-resistant isolates of A. baumannii isolates were collected from blood and respiratory samples of patients with ventilator-associated pneumonia or bacteremia. Microbroth checkerboard assay (CBA) and E-test were performed to look for synergistic interface of sulbactam and tazobactam with meropenem or colistin. All 54 MDR isolates of A. baumannii were resistant to carbapenem. Minimum inhibitory concentration [50/90] value against sulbactam, tazobactam, meropenem, colistin was found to be 64/128, 64/128, 64/256, and 0.5/1.0 respectively. Synergy was detected in more isolates with CBA compared to E-test. All four combinations showed significant synergistic bactericidal activity. However, the combination with colistin showed greater synergistic effect than combination with meropenem. Antagonism was not detected with any of the combinations and any method, but indifference was seen in tazobactam and colistin combination alone. A significant bactericidal effect was seen with sulbactam combination with meropenem or colistin in both methods. A combination therapy can be a choice of treatment. As colistin is known to exhibit nephrotoxicity, the combination of sulbactam and meropenem might be considered as an alternative antibiotic treatment for such multi- and extremely resistant bacteria. Yet, sample size is small in our study, so further well-designed in vitro and clinical studies on large scale should confirm our findings.

Geographical patterns in antimicrobial resistance of acinetobacter in clinical isolates

OBJECTIVES

Acinetobacter spp. has emerged as a threat to the healthcare workers throughout the globe, owing to its property of multidrug resistance. The aim of the present study was to evaluate the antimicrobial resistance patterns of Acinetobacter spp. among indoor and out patients in our hospital and compare the resistance patterns in India and abroad.

MATERIALS AND METHODS

In this retrospective study, which was carried out between Over a period of one year, a total of 5593 clinical specimens of pus and purulent fluids were examined and antimicrobial resistance pattern for Acinetobacter spp. using Modified Stoke's were evaluated. Also a comparison was done with the other similar studies.

STATISTICAL ANALYSIS

Using the proportions of sensitive and resistant, the statistical analysis was done. The total, mean and percentage were calculated by using SPSS.

RESULTS

A high level of antimicrobial multidrug-resistance was found in almost all the clinical isolate. Our study was also found to be concordant with the results of other studies.

CONCLUSION

There is an emerging need for identification of the genes and mechanisms for multidrug resistance among Acinetobacter spp.