Prevalence of Gram-negative and Gram-positive Bacteria and Antibiotic Resistance Rates at a Military Hospital in Riyadh Region

Background: Our study was done to determine the pattern of antibiotic resistance of various strains of bacteria causing acute tonsillitis.Methods: the study was a randomized cross sectional study. Patients matching the inclusion criteria were included. Duration of study was 6 months.Results: Out of 120 cases, 46 cases showed no bacterial growth (NBG) and 74 cases showed bacterial growth. 42 cases were gram-negative bacterial strain and 32 cases were positive bacterial strain out of 72 bacterial grown cases. A list of 25 antibiotic drugs in gram-negative and 31 drugs in gram-positive strain, their sensitivity and resistance were taken and noted. Among gram-negative bacteria imipenem (71.4%) showed highest sensitivity. Highest antibiotic resistance was seen in ampicillin (85.71%). Least sensitivity is observed in clindamycin, amoxicillin+clavulanic acid with 2.38%. Among gram-positive bacteria, highest sensitivity was noted in cefotaxime (75%). Highest antibiotic resistance was seen in cotrimoxazole (46.8%). Least sensitivity is observed in netilmicin, sulbactam with 3.12%.Conclusions: The number of drugs resistant to the gram-positive bacteria are lesser than number of drugs sensitive, which showed significant difference (p<0.05). Significant difference of antibiotic drugs was not found in gram-negative bacteria. Our study findings helped in appropriate and guarded use of the antibiotic drugs in acute tonsillitis, minimizing the exposure of individuals to antibiotic resistance by choosing an appropriate sensitive drug, therefore improving the quality of therapy.

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Antibiotic resistance pattern in intensive care unit of a tertiary care teaching hospital

International Journal of Basic & Clinical Pharmacology ◽

10.18203/2319-2003.ijbcp20181633 ◽

2018 ◽

Vol 7 (5) ◽

pp. 906

Author(s):

Amit Bhatia ◽

Juhi Kalra ◽

Saurabh Kohli ◽

Barnali Kakati ◽

Reshma Kaushik

Keyword(s):

Intensive Care Unit ◽

Drug Resistance ◽

Antibiotic Resistance ◽

Intensive Care ◽

Teaching Hospital ◽

Tertiary Care ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

Background: Antimicrobials are a major class of drugs prescribed in Intensive Care Unit (ICU). Widespread use of empirical antibiotic therapy has facilitated the emergence of drug resistance, since empirical therapy is very often initiated at the outset, even before culture and sensitivity reports are available. The problem of drug resistance is on a rise, therefore, this study was planned to assess the drug resistance and sensitivity patterns of the blood isolates recovered from ICU.Methods: An observational- prospective study was conducted in the Tertiary care teaching hospital over a period of twelve months to assess antibiotic resistance and sensitivity pattern. A total of 104 consecutive patients receiving antibiotics in the ICU and having blood cultures with significant growth were included in the study. Blood sample was collected and after obtaining a culture growth, the identification and antimicrobial sensitivity testing was done.Results: Blood stream infection by Gram-negative bacteria (50.96%) was more common than Gram-positive bacteria (49.04%). Coagulase negative Staphylococci (CoNS) was the predominant single blood culture isolate (35.58%). Klebsiella pneumoniae (13.46%), Escherichia coli (12.50%), Acinetobacter baumannii complex (7.69%) were commonly isolated gram negative organisms. Gram positive isolates were resistant to beta lactams in maximum patients whereas Tigecycline, Linezolid, Daptomycin, Vancomycin, Nitrofurantoin and Teicoplanin were sensitive against them. Common gram negative isolates were sensitive to Colistin and Tigecycline but resistant to most of the antibiotics.Conclusions: A preponderance of gram negative bacteria over gram positive bacteria was noted with a higher degree of resistance to most of the first line antimicrobial agents.

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Antibiotic resistance pattern of bacterial isolates retrieved from febrile neutropenic patients with hematological disorders

10.21203/rs.3.rs-24936/v1 ◽

2020 ◽

Author(s):

Gayatri Prajapati ◽

Bishesh Sharma Poudyal ◽

Krishna Kumar Maharjan ◽

Sunita Prajapati ◽

Janak Raj Dhungana

Keyword(s):

Staphylococcus Aureus ◽

Antibiotic Resistance ◽

Effective Treatment ◽

Resistance Pattern ◽

Gram Negative Bacteria ◽

Gram Positive ◽

Gram Negative ◽

Hematological Disorders ◽

Gram Positive Bacteria ◽

Neutropenic Patients

Abstract Background Antibiotic resistance is nowadays becoming a threat in the treatment of immunosuppressed patients. The aim of this study was to find out the antibiotic resistance pattern of bacteria isolated from febrile neutropenic patients with hematological disorders so that it would help to select the empirical antibiotic for prompt effective treatment of the febrile neutropenic patients. Methods A cross-sectional descriptive study was conducted at a tertiary care hospital of Nepal from October 2018 to November 2019. Blood was drawn aseptically in blood culture bottles. The bacteria were identified by standard microbiological methods with observation of colony morphology, gram staining and biochemical tests of bacteria. The antibiotic susceptibility tests were done by Kirby Bauer disc diffusion method. Extended Spectrum Beta Lactamase (ESBL) and Metallo Beta Lactamase (MBL) producers, and Methicillin Resistant Staphylococcus aureus (MRSA) were detected by phenotypic methods. Results Of the total 214 blood samples, 33.9% (71) yielded the bacterial growth. Gram negative bacteria were isolated from 23.8% of total samples and Gram-positive bacteria were isolated from 9.3% of the total samples. The Gram negative bacteria isolated were Escherichia coli (7.9%), Klebsiella pneumoniae (4.7%), Citrobacter spp. (4.7%), Acinetobacter spp. (3.7%) and Pseudomonas aeruginosa (2.8%). The Gram-positive bacteria isolated were Staphylococcus aureus (5.6%), Coagulase Negative Staphylococcus (2.3%) and Enterococcus spp. (1.4%). About 66.7% of the total Gram-negative bacteria isolated and 50% of the total Gram-positive bacteria were MDR (Multidrug-resistant). About 19.6% of the total Gram-negative bacteria were ESBL producers and 19.6% of them were MBL producers. About 41.6% of Staphylococcus aureus isolated were MRSA (Methicillin Resistant S. aureus). In our institution, piperacillin-tazobactam is the preferred first choice empirical antibiotic. But 58.8% of the Gram negative organisms were found to be resistant towards piperacillin-tazobactam. Hence there is a prompt necessity to switch to another antibiotic with high sensitivity for effective treatment of the febrile neutropenic patients in our institution. Conclusion Antibiotic surveillance data should be evaluated periodically to select the empirical therapeutic antibiotic for effective treatment of febrile neutropenic patients.

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High Prevalence of Antibiotic Resistance among Opportunistic Pathogens Isolated from Patients with COVID-19 under Mechanical Ventilation: Results of a Single-Center Study

Antibiotics ◽

10.3390/antibiotics10091080 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1080

Author(s):

Chiara Temperoni ◽

Luca Caiazzo ◽

Francesco Barchiesi

Keyword(s):

Mechanical Ventilation ◽

Antibiotic Resistance ◽

Fungal Infections ◽

Common Species ◽

Opportunistic Pathogens ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

High Prevalence ◽

Empiric Antibiotic

The effect of the COVID-19 pandemic on antibiotic resistance diffusion in healthcare settings has not been fully investigated. In this study we evaluated the prevalence of antibiotic resistance among opportunistic pathogens isolated from patients with COVID-19 under mechanical ventilation. An observational, retrospective, analysis was performed on confirmed cases of COVID-19 patients who were admitted to the ICU department of S. Salvatore Hospital in Pesaro, Italy, from 1 February 2021 to 31 May 2021. We considered all consecutive patients aged ≥ 18, under mechanical ventilation for longer than 24 h. Eighty-nine patients, 66 (74.1%) men and 23 (25.9%) women, with a median age of 67.1 years, were recruited. Sixty-eight patients (76.4%) had at least one infection, and 11 patients (12.3%) were colonized, while in the remaining 10 patients (11.2%) neither colonization nor infection occurred. In total, 173 microorganisms were isolated. There were 73 isolates (42.2%) causing bacterial or fungal infections while the remaining 100 isolates (57.8%) were colonizers. Among Gram-negative bacteria, E.coli, A.baumannii and K.pneumoniae were the most common species. Among Gram-positive bacteria, S.aureus and E.faecalis were the most common species. Overall, there were 58/105 (55.2%) and 22/59 (37.2%) MDR isolates among Gram-negative and Gram-positive bacteria, respectively. The prevalence of an MDR microorganism was significantly higher in those patients who had been exposed to empiric antibiotic treatment before ICU admission. In conclusion, we found a high prevalence of antibiotic resistance among opportunistic pathogens isolated from patients with COVID-19 under mechanical ventilation.

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The antibiotic negamycin crosses the bacterial cytoplasmic membrane by multiple routes

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00986-20 ◽

2021 ◽

Author(s):

Daniel Hörömpöli ◽

Catherine Ciglia ◽

Karl-Heinz Glüsenkamp ◽

Lars Ole Haustedt ◽

Hildegard Falkenstein-Paul ◽

...

Keyword(s):

Cytoplasmic Membrane ◽

Binding Mode ◽

Blood Levels ◽

Gram Positive ◽

Gram Negative ◽

Bacterial Membranes ◽

Target Interaction ◽

Gram Positive Bacteria ◽

Multiple Routes ◽

Resistance Rates

Negamycin is a natural pseudo-dipeptide antibiotic with promising activity against Gram-negative and Gram-positive bacteria, including Enterobacteriaceae, Pseudomonas aeruginosa, and Staphylococcus aureus, and good efficacy in infection models. It binds to ribosomes with a novel binding mode, stimulating miscoding and inhibiting ribosome translocation. We were particularly interested in studying how the small, positively charged natural product reaches its cytoplasmic target in Escherichia coli. Negamycin crosses the cytoplasmic membrane by multiple routes depending on environmental conditions. In a peptide-free medium, negamycin uses endogenous peptide transporters for active translocation, preferentially the dipeptide permease Dpp. However, in the absence of functional Dpp or in the presence of outcompeting nutrient peptides, negamycin can still enter the cytoplasm. We observed a contribution of the DppA homologs SapA and OppA, as well as of DtpD, a proton-dependent oligopeptide transporter. Calcium strongly improves the activity of negamycin against both Gram-negative and Gram-positive bacteria, especially at concentrations around 2.5 mM, reflecting human blood levels. Calcium forms a complex with negamycin and facilitates its interaction with negatively charged phospholipids in bacterial membranes. Moreover, decreased activity at acidic pH and under anaerobic conditions point to a role of the membrane potential in negamycin uptake. Accordingly, improved activity at alkaline pH could be linked to increased uptake of [3H]negamycin. The diversity of options for membrane translocation is reflected by low resistance rates. The example of negamycin demonstrates that membrane passage of antibiotics can be multi-faceted and that for cytoplasmic anti-Gram-negative drugs, understanding of permeation and target interaction are equally important.

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The Antibiotic Resistance Profiles of Bacterial Strains Isolated from Patients with Hospital-Acquired Bloodstream and Urinary Tract Infections

Critical Care Research and Practice ◽

10.1155/2012/890797 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Hamed Ghadiri ◽

Hamid Vaez ◽

Samira Khosravi ◽

Ebrahim Soleymani

Keyword(s):

Antibiotic Resistance ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Resistance Rate ◽

Antibiotics Resistance ◽

Gram Positive ◽

Gram Negative ◽

E Coli ◽

Gram Positive Bacteria ◽

Tract Infections

Treatment of nosocomial infections is becoming difficult due to the increasing trend of antibiotics resistance. Current knowledge on antibiotic resistance pattern is essential for appropriate therapy. We aimed to evaluate antibiotic resistance profiles in nosocomial bloodstream and urinary tract pathogens. A total of 129 blood stream and 300 urinary tract positive samples were obtained from patients referring to Besat hospital over a two-year period (2009 and 2010). Antibiotic sensitivity was ascertained using the Kirby-Bauer disk diffusion technique according to CLSI guidelines. Patient's data such as gender and age were recorded. The ratio of gram-negative to gram-positive bacteria in BSIs was 1.6 : 1. The most prevalent BSI pathogen was Coagulase-NegativeStaphylococci(CoNS). The highest resistance rate of CoNS was against penicillin (91.1%) followed by ampicillin (75.6%), and the lowest rate was against vancomycin (4.4%).Escherichia coliwas the most prevalent pathogen isolated from urinary tract infections (UTIs). Ratio of gram-negative to gram-positive bacteria was 3.2 : 1. The highest resistance rate ofE. coliisolates was against nalidixic acid (57.7%). The present study showed that CoNS andE. coliare the most common causative agents of nosocomial BSIs and UTIs, and control of infection needs to be addressed in both antibiotic prescription and general hygiene.

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Conjugative Plasmid Transfer in Gram-Positive Bacteria

Microbiology and Molecular Biology Reviews ◽

10.1128/mmbr.67.2.277-301.2003 ◽

2003 ◽

Vol 67 (2) ◽

pp. 277-301 ◽

Cited By ~ 373

Author(s):

Elisabeth Grohmann ◽

Günther Muth ◽

Manuel Espinosa

Keyword(s):

Antibiotic Resistance ◽

Plasmid Transfer ◽

Translocator Protein ◽

Conjugative Plasmid ◽

Gram Negative Bacteria ◽

Secretion Systems ◽

Gram Positive ◽

Severe Problem ◽

Gram Negative ◽

Gram Positive Bacteria

SUMMARY Conjugative transfer of bacterial plasmids is the most efficient way of horizontal gene spread, and it is therefore considered one of the major reasons for the increase in the number of bacteria exhibiting multiple-antibiotic resistance. Thus, conjugation and spread of antibiotic resistance represents a severe problem in antibiotic treatment, especially of immunosuppressed patients and in intensive care units. While conjugation in gram-negative bacteria has been studied in great detail over the last decades, the transfer mechanisms of antibiotic resistance plasmids in gram-positive bacteria remained obscure. In the last few years, the entire nucleotide sequences of several large conjugative plasmids from gram-positive bacteria have been determined. Sequence analyses and data bank comparisons of their putative transfer (tra) regions have revealed significant similarities to tra regions of plasmids from gram-negative bacteria with regard to the respective DNA relaxases and their targets, the origins of transfer (oriT), and putative nucleoside triphosphatases NTP-ases with homologies to type IV secretion systems. In contrast, a single gene encoding a septal DNA translocator protein is involved in plasmid transfer between micelle-forming streptomycetes. Based on these clues, we propose the existence of two fundamentally different plasmid-mediated conjugative mechanisms in gram-positive microorganisms, namely, the mechanism taking place in unicellular gram-positive bacteria, which is functionally similar to that in gram-negative bacteria, and a second type that occurs in multicellular gram-positive bacteria, which seems to be characterized by double-stranded DNA transfer.

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Overview on the role of heavy metals tolerance on developing antibiotic resistance in both Gram-negative and Gram-positive bacteria

Archives of Microbiology ◽

10.1007/s00203-021-02275-w ◽

2021 ◽

Author(s):

Raju Biswas ◽

Urmi Halder ◽

Ashutosh Kabiraj ◽

Amit Mondal ◽

Rajib Bandopadhyay

Keyword(s):

Heavy Metals ◽

Antibiotic Resistance ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Metals Tolerance

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Analysis of pathogenic distribution and drug resistance of catheter-related blood stream infection in hemodialysis patients with vein tunneled cuffed catheter

European Journal of Inflammation ◽

10.1177/20587392211000887 ◽

2021 ◽

Vol 19 ◽

pp. 205873922110008

Author(s):

Wei Ren ◽

Jun Jiang ◽

Yan Wang ◽

Yan Jin ◽

Yuan Fang ◽

...

Keyword(s):

Drug Resistance ◽

Blood Culture ◽

Blood Stream ◽

Resistance Rate ◽

Penicillin G ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria ◽

Positive Rate ◽

Resistance Rates

The catheter related blood stream infections (CRBSI) in hemodialysis (HD) patients with vein tunneled cuffed catheter (TCC) and misuse of antibiotic in clinical practice seriously affected the prognosis of MHD patients. The present study aimed to investigate the pathogen distribution and drug resistance of CRBSI in HD patients with TCC to guide clinical empirical pharmacy. The clinical data of 75 HD patients with TCC diagnosed with CRBSI between January 2011 and March 2015 were retrospectively collected, and the distribution and drug resistance of pathogens were analyzed. In 75 HD patients with TCC diagnosed with CRBSI, there were 33 patients with positive blood culture, and the positive rate of blood culture was 44%. The majority of the 33 pathogens were Gram-positive bacteria (22 strains, accounting for 66.7%). Gram-positive cocci hardly resisted to vancomycin and linezolid, while the resistance rate to penicillin G nearly reached to 100%. Gram-negative bacilli had low resistance rates to carbapenems and quinolone antibiotics, and the resistance rate to cephalosporins antibioticsexceeding 50%. The positive rate of blood culture in 75 HD patients with TCC diagnosed with CRBSI is low. The pathogens resulting in CRBSI in HD patients are mainly Gram-positive bacteria which are significantly resistant to penicillin G, and have a low resistance rate to methicillin. Gram-negative bacteria have high resistance rates to commonly used antibiotics. The pathogen examination should be performed as early as possible and effective antibiotics should be chosen according to drug sensitivity test results in CRBSI in HD patients.

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Microanatomy of the Periplasm of Bacillus Licheniformis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065365 ◽

1971 ◽

Vol 29 ◽

pp. 262-263

Author(s):

B.K. Ghosh

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Bacillus Licheniformis ◽

External Environment ◽

Permeability Barrier ◽

Periplasmic Space ◽

Modified Technique ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

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