Bacteriological and resistance profile in isolates from diabetic patients

Antimicrobial Resistance Patterns and Virulence Gene Profiles of Klebsiella pneumoniae Isolated from Surgical Site Infections in Iran

Background: The prevalence of Klebsiella pneumoniae in surgical site infections (SSIs) has increased recently. This study aimed to evaluate the antimicrobial resistance patterns and biofilm formation capacity of K. pneumoniae strains isolated from SSIs. Methods: A total of 63 K. pneumoniae isolates were obtained from patients with SSIs. Antimicrobial susceptibility testing was determined using the Kirby-Bauer method. Molecular analyses were performed to confirm the presence of virulence and antibiotic resistance genes. Biofilm formation was determined using a semiquantified microtiter plate assay, and optical density measurements were used to classify the isolates into weak, moderate, and strong biofilm producers. Biofilm structure was observed using field-emission scanning electron microscopy. Statistical analyses were performed using SPSS software version 16 (SPSS Inc., Chicago, IL, USA), and data were analyzed and presented in terms of frequency and percentage. Results: The frequencies of fimH, mrkD, mrkA, wcaG, and magA were 98.4%, 96.8%, 77.7%, 61.9%, and 7.9%, respectively. The highest rates of antibiotic resistance were observed for cefazolin, cefuroxime, and piperacillin/tazobactam and 98.4% of the isolates were resistant to at least one antibiotic agent. The most prevalent resistance genes were blaSHV (42.8%), blaCTX-M (31.7%), blaTEM (28.5%), and blaOXA48 (22.2%). All the tested isolates were able to produce biofilms, and 76.2% were classified as strong biofilm producers. Conclusions: Klebsiella pneumoniae is one of the common pathogens in SSIs, and due to its antibiotic resistance and the presence of multiple virulence factors, proper controlling strategies need to be carried out.

Factors associated with severity and outcomes of diabetic foot ulcers: A single center hospital-based cross-sectional observational study in Eastern India

Background

Diabetes mellitus (DM) affects millions globally and is associated with high morbidity, risk of infection, and potential for severe outcomes. In India, where the prevalence of diabetic foot complications is notably high, data on factors influencing the severity and outcomes of diabetic foot ulcers (DFUs) in specific regions, particularly Eastern India, remain sparse.

Methods

This hospital-based cross-sectional study included Type 2 DM patients aged over 18 years, excluding those unwilling to participate and those with ulcers classified as Wagner grade less than 2. The study involved the complete enumeration of eligible patients presenting with DFUs. Clinical and demographic data were collected, including glycemic control, physical activity levels, and microbial cultures from ulcer specimens.

Results

The study included 90 patients with a mean age of 56.1 years. Most participants were male (76.7%), with 47.8% receiving regular diabetes treatment and only 10% achieving good glycemic control. Positive swab cultures were found in 68.9% of patients, predominantly mono-microbial. Higher grade ulcers were associated with male gender (AOR 5.715), and positive swab cultures (AOR 17.470). Moderate-to-severe physical activity (AOR 9.683) and paresthesia (AOR 0.101) were significant predictors of gangrene, with absent distal pulses (COR 13.818) also indicating a higher risk for gangrene. Good glycemic control was associated with a reduced risk of gangrene (COR 0.125).

Conclusions

Maintaining good glycemic control is crucial in preventing complications such as gangrene. Physical activity is generally beneficial in DM; however, excessive or high-impact activities may exacerbate existing foot ulcers and increase the risk of gangrene.

Microbial Etiology, Antimicrobial Resistance, and Risk Factors of Surgical Site Infections in Gestational Diabetes Mellitus Patients Undergoing Elective Pre-Labor Cesarean Deliveries

Background

Gestational Diabetes Mellitus (GDM) significantly increases the risk of adverse pregnancy outcomes, including elective pre-labor cesarean deliveries. Postoperative surgical site infections (SSIs) pose a significant concern, underscoring the need for a detailed investigation into their causes and preventative measures. The aim of this study is to systematically identify and analyze the microbial etiology and antimicrobial resistance profiles of pathogens responsible for SSIs in GDM patients undergoing elective pre-labor cesarean deliveries. Additionally, this research aims to elucidate the risk factors contributing to SSIs, with a specific focus on operation duration, amniotic fluid contamination, and genital tract inflammation, and their correlation with the incidence of SSIs.

Methods

A retrospective analysis was conducted at our Hospital between September 2018 and July 2023, involving 150 GDM patients who underwent elective pre-labor cesarean deliveries. Patients were categorized into infected and uninfected groups based on postoperative SSIs. Clinical data were meticulously collected and analyzed using SPSS software (version 27.0). Independent sample t-tests and chi-square tests were employed for statistical analysis.

Results

Microbial profiling revealed that Gram-negative bacteria, primarily E. coli, constituted approximately 59.46% of the isolated strains, exhibiting significant resistance to commonly used antibiotics such as ampicillin and cefotaxime. Elevated levels of biomarkers, including Procalcitonin (PCT) and Hemoglobin A1c (HbA1c), were significantly associated with SSIs. Multivariate logistic regression analysis identified operation time ≥1-hour, amniotic fluid contamination, and genital tract inflammation as significant risk factors.

Conclusion

This study highlights the microbial etiology, resistance patterns, and risk factors for SSIs in GDM cesarean patients, emphasizing the need for tailored preoperative evaluations.

A Multicenter Experience of Inducible Clindamycin Resistance in Staphylococcus aureus Infection among 800 Egyptian Patients with or without Diabetes Mellitus

Staphylococcus aureus causes a wide range of illnesses, from skin infections and persistent bone infections to life-threatening septicemia and endocarditis. Methicillin-resistant S. aureus (MRSA) is one of the most common bacteria that cause nosocomial and community-acquired infections. Clindamycin is one of the most effective treatments for several bacterial infections. Despite this, these infections may develop inducible clindamycin resistance during treatment, leading to treatment failure. This study determined the incidence of inducible clindamycin resistance among S. aureus clinical isolates. A total of 800 S. aureus strains were identified from clinical samples collected from several university hospitals in Egypt. All isolates were examined for the presence of MRSA using cefoxitin (30 μg) and the Kirby Bauer disk diffusion technique. The induction phenotypes of all 800 S. aureus strains were evaluated using the disk approximation test (D test), as recommended by the Clinical and Laboratory Standard Institute. Of the 800 strains of S. aureus, 540 (67.5%) were identified as MRSA and 260 (32.5%) were classified as methicillin-sensitive S. aureus (MSSA). In MRSA infections, clindamycin constitutive and inducible resistance was more frequent than in MSSA infections (27.8% versus 11.5% and 38.9% versus 15.4%, respectively). Clindamycin-sensitive strains were more prevalent in MSSA (53.8%) than in MRSA (20.4%) infections. In conclusion, the frequency of constitutive and inducible clindamycin resistance in MRSA isolates emphasizes the need to use the D test in routine antimicrobial susceptibility testing to evaluate clindamycin susceptibility, as the inducible resistance phenotype can inhibit the action of clindamycin and thus affect treatment efficacy.

Genomic Characterization of International High-Risk Clone ST410 Escherichia coli Co-Harboring ESBL-Encoding Genes and blaNDM-5 on IncFIA/IncFIB/IncFII/IncQ1 Multireplicon Plasmid and Carrying a Chromosome-Borne blaCMY-2 from Egypt

The accelerated dispersion of multidrug-resistant (MDR) Escherichia coli due to the production of extended-spectrum β-lactamases (ESBLs) or AmpC enzymes has been noted in Egypt, presenting a serious treatment challenge. In this study, we investigate the prevalence of ESBLs and AmpC enzymes among 48 E. coli isolates collected from patients with urinary tract infections admitted to a teaching hospital in Alexandria. Phenotypic and genotypic methods of detection are conducted. Isolates producing both enzymes are tested for the mobilization of their genes by a broth mating experiment. Whole genome sequencing (WGS) is performed for isolate EC13655. The results indicate that 80% of the isolates are MDR, among which 52% and 13% were ESBL and AmpC producers, respectively. Conjugation experiments fail to show the mobilization of blaCMY-2 in EC13655, which was chosen for WGS. In silico analysis reveals that the isolate belongs to a ST410-H24Rx high-risk clone. It coharbors the ESBL-encoding genes blaCTX-M-15, blaTEM-1, and blaOXA-1 on an IncFIA/IncFIB/IncFII/IncQ1 multireplicon plasmid. The chromosomal location of blaCMY-2 is detected with a flanking upstream copy of ISEcp1. This chromosomal integration of blaCMY-2 establishes the stable maintenance of the gene and thus, necessitates an imperative local surveillance to reduce further spread of such strains in different clinical settings.

'Perceptions' and 'practices' to antibiotic usage among diabetic patients receiving care from a rural tertiary care center: A mixed-methods study

BACKGROUND

Contribution to antibiotic resistance can happen at two interfaces - doctor prescribing antibiotics inadvertently or patient's usage of antibiotics inadvertently. This study was conducted among diabetic inpatients in a rural tertiary health center in Kolar, South India, to assess the various practices related to antibiotic use and to explore the possible reasons for these practices with regard to antibiotic use.

MATERIALS AND METHODS

An exploratory sequential mixed-methods study was conducted with an initial cross-sectional quantitative study followed by qualitative in-depth interviews during August-September 2019. A pretested semi-structured questionnaire was used to capture the sociodemographic, disease-, and treatment-related characteristics and practices related to antibiotic use. An open-ended interview guide was used to conduct in-depth interviews. The practices to antibiotic use were reported using frequency (percentage). Manual descriptive content analyses were done by two investigators separately to identify codes under the broad topic "reasons for adopted practices with regard to antibiotic use."

RESULTS

Of the 152 diabetic inpatients interviewed, 20 (13.2%) felt that antibiotics are safe drugs and can be used commonly. Among these inpatients, seven (4.6%) knew that antibiotics can kill bacteria and four (2.6%) perceived 'antibiotic resistance' as a big problem in India. The practice of checking the expiry date before using antibiotics was seen in 21 (13.8%) and 44 (29%) of them finished the full course of antibiotics. A total of six codes were identified under the broad theme of "reasons for adopted practices with regard to antibiotic use" among diabetic inpatients.

CONCLUSIONS

Less than one-third of them completed the antibiotic course given by the doctor, and almost everyone was ready for over-the-counter purchase of antibiotics offered by the pharmacist. The reasons for such practices were mostly attributed to the "partial drug purchases" and "incomplete advice by the doctor." There is an urgent need to plan and deliver an interventional package to enhance the knowledge and inculcate good antibiotic usage practices among these high-risk populations.

Vancomycin-Induced Modulation of Gram-Positive Gut Bacteria and Metabolites Remediates Insulin Resistance in iNOS Knockout Mice

The role of oxidative and nitrosative stress has been implied in both physiology and pathophysiology of metabolic disorders. Inducible nitric oxide synthase (iNOS) has emerged as a crucial regulator of host metabolism and gut microbiota activity. The present study examines the role of the gut microbiome in determining host metabolic functions in the absence of iNOS. Insulin-resistant and dyslipidemic iNOS-/- mice displayed reduced microbial diversity, with a higher relative abundance of Allobaculum and Bifidobacterium, gram-positive bacteria, and altered serum metabolites along with metabolic dysregulation. Vancomycin, which largely depletes gram-positive bacteria, reversed the insulin resistance (IR), dyslipidemia, and related metabolic anomalies in iNOS-/- mice. Such improvements in metabolic markers were accompanied by alterations in the expression of genes involved in fatty acid synthesis in the liver and adipose tissue, lipid uptake in adipose tissue, and lipid efflux in the liver and intestine tissue. The rescue of IR in vancomycin-treated iNOS-/- mice was accompanied with the changes in select serum metabolites such as 10-hydroxydecanoate, indole-3-ethanol, allantoin, hippurate, sebacic acid, aminoadipate, and ophthalmate, along with improvement in phosphatidylethanolamine to phosphatidylcholine (PE/PC) ratio. In the present study, we demonstrate that vancomycin-mediated depletion of gram-positive bacteria in iNOS-/- mice reversed the metabolic perturbations, dyslipidemia, and insulin resistance.

Modulation of Insulin Resistance, Dyslipidemia and Serum Metabolome in iNOS Knockout Mice following Treatment with Nitrite, Metformin, Pioglitazone, and a Combination of Ampicillin and Neomycin

Oxidative and nitrosative stress plays a pivotal role in the incidence of metabolic disorders. Studies from this lab and others in iNOS-/- mice have demonstrated occurrence of insulin resistance (IR), hyperglycemia and dyslipidemia highlighting the importance of optimal redox balance. The present study evaluates role of nitrite, L-arginine, antidiabetics (metformin, pioglitazone) and antibiotics (ampicillin-neomycin combination, metronidazole) on metabolic perturbations observed in iNOS-/- mice. The animals were monitored for glucose tolerance (IPGTT), IR (insulin, HOMA-IR, QUICKI), circulating lipids and serum metabolomics (LC-MS). Hyperglycemia, hyperinsulinemia and IR were rescued by nitrite, antidiabetics, and antibiotics treatments in iNOS-/- mice. Glucose intolerance was improved with nitrite, metformin and pioglitazone treatment, while ampicillin-neomycin combination normalised the glucose utilization in iNOS-/- mice. Increased serum phosphatidylethanolamine lipids in iNOS-/- mice were reversed by metformin, pioglitazone and ampicillin-neomycin; dyslipidemia was however marginally improved by nitrite treatment. The metabolic improvements were associated with changes in selected serum metabolites-purines, ceramide, 10-hydroxydecanoate, glucosaminate, diosmetin, sebacic acid, 3-nitrotyrosine and cysteamine. Bacterial metabolites-hippurate, indole-3-ethanol; IR marker-aminoadipate and oxidative stress marker-ophthalmate were reduced by pioglitazone and ampicillin-neomycin, but not by nitrite and metformin treatment. Results obtained in the present study suggest a crucial role of gut microbiota in the metabolic perturbations observed in iNOS-/- mice.

Antimicrobial Resistance Patterns in Diabetic Foot Infections, an Epidemiological Study in Northeastern Italy

This study is a retrospective epidemiological assessment of bacterial species isolated from a cohort of out-patients with diabetic foot infections referred to our “Diabetic Foot Unit” over one year, with particular attention to index pathogens, as identified by the EARS Network. Staphylococcus aureus and Pseudomonas aeruginosa accounted for 33.5% and 11.9% of cases, respectively. MRSA was isolated in 27.1% of patients, with 14.06% showing additional resistance to three antimicrobial classes. Pseudomonas aeruginosa presented extensive resistance to fluoroquinolones (57.3%), which was associated with resistance to piperacillin in 17.6% or to carbapenems in 23.5% of cases. Other pathogens, such as methicillin resistantStaphylococcus epidermidis, Escherichia coli and Morganella morganii ESBL and Enterococcus faecium VRE, were also found.

Phenotypic Identification and Genotypic Characterization of Plasmid-Mediated AmpC β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae Isolates in Iran

One of the mechanisms of Klebsiella pneumoniae and Escherichia coli resistance to β-lactam antibiotics is the production of β-lactamase enzymes. Among these are the AmpC β-lactamases, which confer resistance to a class of antibiotics. However, little is known about the AmpC β-lactamases of K. pneumoniae and E. coli clinical isolates in Qazvin, Iran. This study was designed to assess the AmpC β‑lactamases-producing strains and also identify the prevalence of AmpC β‑lactamases genes. Antimicrobial susceptibility tests were performed on 435 K. pneumoniae and E. coli isolates using disk diffusion technique. Plasmid-mediated AmpC genes were studied using a multiplex PCR assay. The AmpC β-lactamase-producer isolates were studied by employing cefoxitin disk diffusion test, AmpC induction test, AmpC cefoxitin-EDTA test, and boronic acid disk test. Our results showed that of 46 (18.4%) cefoxitin-insensitive E. coli isolates, 10 (21.7%) were positive for AmpC β-lactamase genes, among them 4 (8.69%) isolates were positive for bla_DHA genes and 6 (13%) for bla_CIT genes. Of 57 (30.4%) cefoxitin-insensitive K. pneumoniae isolates, 10 (17.5%) were positive for AmpC gene with 4 (6.34%) and 6 (9.5%) isolates positive for bla_DHA and bla_CIT genes, respectively. However, no MOX, ACC, FOX, or EBC genes were detected in the isolates. Considering the results of different confirmatory phenotypic tests, the AmpC cefoxitin-EDTA test showed a higher discriminatory power for detecting AmpC β-lactamase-producing strains. The specificity and sensitivity of AmpC cefoxitin-EDTA were 77%, 100% for K. pneumonia and 70%, 90% for E. coli higher than the other two tests, respectively. Also, the authors demonstrated high prevalence rate for resistance to certain antibiotics, such as cefuroxime, trimethoprim-sulfamethoxazole, ampicillin, and cefotaxime. In conclusion, our study provided valuable information regarding the plasmid-mediated AmpC β-lactamase gene content, antibiotic resistance, and confirmatory phenotypic tests for AmpC β-lactamases in E. coli and K. pneumoniae isolates from clinical sources.

Bacteriological profile and antibiotic susceptibility of diabetic Foot infections at Ribat University hospital; a retrospective study from Sudan

Purpose

Diabetic foot infection (DFI) is one of the most feared complications of diabetes. In Sudan, the number of cases and the problems associated with diabetic foot infections increased in recent years. This study aimed to assess the bacteriological profile of patients with DFIs and their antibiotic susceptibility pattern.

Methods

A descriptive retrospective cross-sectional study was carried out at Surgery Department of Ribat University Hospital. All medical records of patients with DFIs during the period from September 2017 to February 2019 were reviewed using data collection sheet. The collected data were analyzed using Statistical Package for Social Sciences.

Results

Out of 250 DFI patients, 73.2% of them were males, and 86.4% of them had type 2 diabetes mellitus, and most of them suffered from diabetes for more than 10 years. Regarding culture results, 64.7% and 35.3% of the samples revealed presence of single microorganism and mixed infections, respectively. A total of 335 bacterial isolates were identified, gram-negative were more prevalent than gram-positive organisms. The most frequently isolated organisms were Proteus spp. Staphylococcus aureus, and Escherichia coli. Furthermore, antibiotic susceptibility pattern showed that imipenem, amikacin and vancomycin have the highest activity against isolated bacteria, and all isolates were found to be completely resistant to different cephalosporin drugs.

Conclusion

Among the studied samples, gram-negative bacteria were found to be more common in DFI patients, Proteus spp. and S. aureus were the most common microorganisms. Moreover, different isolated microorganisms showed to have different degrees of resistance and sensitivity to various antibacterial drugs.

Evaluation of various risk factors associated with multidrug-resistant organisms isolated from diabetic foot ulcer patients

AIMS:

Diabetic foot ulcer is a dreaded complication of diabetes. Diabetic foot ulcer patients are often infected with multidrug resistant organism (MDRO) due to chronic course of the wound, inappropriate antibiotics treatment, frequent hospital admission, neuropathy, nephropathy, and peripheral vascular disease.

MATERIALS AND METHODS:

This prospective study was conducted in our 750 bedded hospital for a period of 6 months. The present study was undertaken to isolate various MDRO methicillin resistant Staphylococcus aureus; Gram-negative bacteria producing enzymes such as extended spectrum beta-lactamases (ESBL), Amp C, Carbapenamases; Pseudomonas and Acinetobacter species producing metallo-beta-lactamases (MBL). In addition we attempted to identify risk factors for association of diabetic foot ulcer and MDRO.

RESULTS:

A total of 149 bacterial isolates were identified. Of the total isolates 73.2% were Gram-negative and remaining 26.8% were Gram-positive bacteria. Among Enterobacteriaceae 59% were ESBL producers and 48% were Amp C producers. In addition, 41.5% of the isolates produced both ESBL and Amp C and 13.4% were carbapenem resistant Enterobacteriaceae. Among 20 Pseudomonas and Acinetobacter isolates, 5 were MBL producers (25%). Furthermore, in the study, 56% of patients with diabetic foot ulcer harbored MDRO. The risk of multidrug-resistant infection is significantly more in patients having diabetes duration >20 years and size of ulcer more than 4 cm².

CONCLUSION:

The detection of MDRO in patients of diabetic foot ulcer changes the treatment strategies limits the antimicrobial options and causes higher complications among them.

High prevalence of blaCMY AmpC beta-lactamase in ESBL co-producing Escherichia coli and Klebsiella spp. clinical isolates in the northeast of Iran

OBJECTIVE

The production of β-lactamase enzymes such as AmpC β-lactamases and extended-spectrum β-lactamases (ESBLs) is among the main mechanisms for resistance to expanded-spectrum cephalosporins. The present study was conducted to investigate the prevalence and molecular epidemiology of plasmid-mediated AmpC beta (β)-lactamase in ESBL co-producing Escherichia coli (E. coli) and Klebsiella spp. (Klebsiella pneumoniae and Klebsiella oxytoca) clinical isolates in the northeast of Iran.

METHODS

A total of 602 E. coli and Klebsiella spp. clinical isolates were collected from three hospitals in Mashhad (northeast of Iran). A combination disk test (CDT) was performed for the phenotypic detection of ESBLs. Screening for the detection of AmpC β-lactamases was performed by a susceptibility test to a cefoxitin disc among ESBL producing isolates. A confirmatory test for AmpC β-lactamases was performed using the Mast® D68C test. Identification of plasmid-mediated AmpC cluster genes was done by multiplex polymerase chain reaction (PCR).

RESULTS

Among 336 ESBL-producing strains, 230 (68.4%) isolates were resistant to cefoxitin. Results of the Mast® D68C test showed that 30% (69/230) of cefoxitin-resistant isolates simultaneously exhibited ESBL and AmpC activity and 22% (51/230) of isolates probably showed multi-drug resistant (MDR) phenotype. Results of multiplex PCR among ESBL-positive isolates showed that, 16.7% (56/336) of isolates were positive for plasmid-borneampC cluster genes, and CMY (38%) was the most frequent genotype of plasmid mediated AmpC.

CONCLUSION

Findings of the study revealed that an increase in the prevalence of ESBL and AmpC co-producer in E. coli and Klebsiella spp. strains may become an important public health issue. Therefore, there is a vital need for surveillance of spread of these clinical isolates.

Antimicrobial susceptibility pattern of aerobes in diabetic foot ulcers in a South-Indian tertiary care hospital

PURPOSE

Diabetic foot infections (DFIs) are major public health concerns. In the view of the ever increasing burden of multidrug-resistant (MDR) organisms, improving the use of antimicrobial agents (AMAs) is a national priority. Objective of the study was to determine antimicrobial susceptibility (AMS) pattern of aerobes in DFIs.

METHODS

A cross-sectional study was conducted for a period of 3 years at Department of Surgery, Kasturba hospital, Manipal, India during which, 260 diabetic foot ulcer (DFU) patients admitted in the general surgery wards were enrolled for the study. These patients' culture specimens were observed as Gram-stained smears and cultured aerobically on blood agar and MacConkey agar plates. AMS test was performed by disc diffusion technique according to Clinical and Laboratory Standards Institute (CLSI) guidelines.

RESULTS

A total of 354 microbes were isolated from the ulcer wounds of 213 diabetic foot patients, with an average of 1.7 organisms per lesion. Monomicrobial infections were less common (n=81; 31.2%) than polymicrobial infections (n=132; 50.7%). Gram-negative bacteria were the most common among the isolates (n=192; 54.2%). Aerobic Gram-positive Cocci accounted for 162 (45.8%) of all isolates. On the other hand, Staphylococcus aureus was the most frequently isolated aerobe (n=106; 29.9%) followed by Pseudomonas aeruginosa (n=91; 25.7%).

CONCLUSION

AMS data from our study recommends that doxycycline would be the appropriate choice as single drug for empirical coverage for Gram-positive organisms. The most appropriate antibiotic for Gram-negative organisms is meropenem. One of the critical observations is the presence of Acinetobacter, an MDR isolated from DFIs, which is either relatively or totally resistant to all the AMAs tested.

Antibacterial activity of Withania somnifera against Gram-positive isolates from pus samples

Background:

Withania somnifera is an important medicinal plant that has been used in Ayurvedic and indigenous medicine since ancient times. In the view of its varied therapeutic potential, it has also been the subject of considerable modern scientific attention. Attention has been drawn to antibacterial activity of the plant and its metabolites due to the challenge on growing antibacterial resistant pathogens.

Aim:

To examine the antimicrobial potential of leaf extract of W. somnifera against Gram-positive cocci.

Materials and Methods:

In this study, leaf extract of W. somnifera was used to examine their antimicrobial potential against Gram-positive cocci (n = 20) from pus samples of patients admitted in Government Medical College, Haldwani. Agar well diffusion method was used by taking methanolic leaf extract of W. somnifera.

Results:

It was observed that the methanolic leaf extract of W. somnifera was very effective in inhibiting the test pathogens including methicillin resistant Staphylococcus aureus and Enterococcus spp., with an average zone of inhibition of 20.6 mm and 19.4 mm at 2 mg/ml (100 μl) concentration, respectively.

Conclusion:

These results indicate that the antimicrobial property of W. somnifera leaf supports the traditional use of the plant in therapeutic use against microbial infections.

Risk factors of community-associated infections in Chinese patients with diabetes: A meta-analysis

Objective

To identify the common sites and risk factors of community-associated infections in Chinese patients with diabetes.

Materials and Methods

The Wanfang, CNKI, PUBMED and VIP databases restricting to Chinese patients with diabetes were queried without restriction to time period. Randomized controlled trials (RCTs) on the risk factors of community-associated infections in Chinese patients with diabetes were considered. Polled odd ratios (OR) and 95% confidence intervals (95% CI) were used for each factor in fixed or random-effect meta-analyses.

Results

Twelve studies were identified that investigated seven risk factors of community-associated infections in Chinese patients with diabetes. The average infection incidence was 39.55%. The respiratory tract and urology tract were the predilection sites. Meta-analysis results are as follows: Diabetic patients with chronic complications (OR: 1.63; 95% CI 1.45–1.82), advanced age (OR: 1.30; 95% CI 1.19–1.42), longer duration (OR: 1.47; 95% CI 1.35–1.61) or ketoacidosis (OR: 1.37; 95% CI 1.13–1.66) were more prone to suffer from infections. Those with better glycemic control (OR: 0.68; 95% CI 0.61–0.76) or males (OR: 0.69; 95% CI 0.64–0.75) were less prone to suffer from infections.

Conclusion

Chinese patients with diabetes had a high incidence of community-associated infections. We should highlight the risk factors that might provide a reference for the same.

Antibiogram of Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus in patients with diabetes

Objective: To determine the antibiogram of Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus (MRSA) in patients with diabetes.

Methods: The study was carried out in the Microbiology Department of Clinical and Research Laboratory, Baqai Institute of Diabetology and Endocrinology (BIDE) from January 2012 to December 2012. All samples received in the laboratory were processed according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Identification of Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus (MRSA) was done and antimicrobial susceptibility pattern was determined by disc diffusion method.

Results: A total of 585 pathogens were isolated from 542 specimens of patients with diabetes. One hundred twenty one (20.68%) Pseudomonas aeruginosa and 25(4.27%) non-aeruginosa Pseudomonas were detected from 542 samples. Among 108 (18%) samples detecting the growth of Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus (MRSA) were found in 42 (39%) samples. Pseudomonas aeruginosa showed marked susceptibility to imipenem (100%) followed by piperacillin / tazobactam (90.91%). All MRSA positive specimens were susceptible to vancomycin, but highly or completely resistant to the other antimicrobial drugs.

Conclusion: In the present study imipenem, piperacillin/tazobactam and sulbactam-cefoperazone were found to be the most effective drugs against Pseudomonas aeruginosa. The majority of MRSA were resistant to one or more than one antimicrobial drugs. Vancomycin and imipenem were the most effective drugsagainstStaphylococcus aureus and MRSA. .

Phenotypic and molecular characterization of plasmid mediated AmpC β-lactamases among Escherichia coli, Klebsiella spp., and Proteus mirabilis isolated from urinary tract infections in Egyptian hospitals

The incidence of resistance by Enterobacteriaceae to β-lactam/β-lactamase inhibitors combination is increasing in Egypt. Three phenotypic techniques, comprising AmpC disk diffusion and inhibition dependent methods using phenylboronic acid (PBA) and cloxacillin, were compared to PCR based method for detection of plasmid mediated AmpC β-lactamase in common urinary tract isolates. A total of 143 isolates, including E. coli, Klebsiella pneumonia, and Proteus mirabilis, were collected from urinary tract infections cases in Egyptian hospitals. Plasmid encoded AmpC genes were detected by PCR in 88.46% of cefoxitin resistant isolates. The most prevalent AmpC gene family was CIT including CMY-2, CMY-4, and two CMY-2 variants. The second prevalent gene was DHA-1 which was detected in E. coli and Klebsiella pneumonia. The genes EBC, FOX, and MOX were also detected but in small percentage. Some isolates were identified as having more than one pAmpC gene. The overall sensitivity and specificity of phenotypic tests for detection of AmpC β-lactamase showed that AmpC disk diffusion and inhibition dependent method by cloxacillin were the most sensitive and the most specific disk tests. PCR remains the gold standard for detection of AmpC β-lactamases. This study represents the first report of CMY-2 variants of CMY-42 and CMY-102 β-lactamase-producing E. coli, Klebsiella pneumonia, and Proteus mirabilis isolates in Egypt.

Target site pharmacokinetics of linezolid after single and multiple doses in diabetic patients with soft tissue infection

The underlying pathology of diabetic wounds, i.e. impairment of macro- and microcirculation, might also impact target site penetration of antibacterial drugs. To compare tissue concentrations of linezolid in infected and not infected tissue 10 patients suffering from type 2 diabetes with foot infection were included in the study. Tissue penetration of linezolid was assessed using in vivo microdialysis at the site of infection as well as in non-inflamed subcutaneous adipose tissue. All patients were investigated after receiving a single dose of linezolid and five patients in addition at steady state. After a single dose of linezolid significantly higher area under the concentration vs. time curve over 8 hours (AUC0-8 ) and maximum concentrations (Cmax )-values were observed in plasma (65.5 ± 21.2 mg*h/L and 16.4 ± 4.6 mg/L) as compared to inflamed (36.3 ± 22.9  mg*h/L and 6.6 ± 3.6 mg/L) and non-inflamed tissue (33.0 ± 17.7 mg*h/L and 6.7 ± 3.6 mg/L). Multiple administrations of linezolid led to disappearance of significant differences in Cmax and AUC0-8 between plasma, inflamed, and non-inflamed tissue. Approximately 2-fold increase of Cmax and AUC0-8 -values in tissue was observed at steady state as compared to the first administration. Penetration of linezolid is not impaired in diabetic foot infection but equilibrium between plasma and tissue might be delayed.

Detection of Different β-Lactamases and their Co-existence by Using Various Discs Combination Methods in Clinical Isolates of Enterobacteriaceae and Pseudomonas spp

Background:

Resistance to broad spectrum beta-lactams mediated by extended spectrum β-lactamase (ESBL), AmpC, and metallobetalactamase (MBLs) enzymes are an increasing problem worldwide. The study was aimed to detect occurrence rate and to evaluate different substrates and inhibitors by disc combination method for detecting varying degree of β-lactamase enzymes and their co-production.

Materials and Methods:

A disc panel containing imipenem (IMP), IMP/EDTA, ceftazidime (CA), ceftazidime-tazobactum (CAT), CAT/cloxacillin (CLOX), ceftazidime-clavulanic acid (CAC), CAC/CLOX, cefoxitin (CN), and CN/CLOX in a single plate was used to detect presence of ESBLs, AmpC, and MBLs and/or their co-existence in 184 consecutive, nonrepetitive, clinical isolates of Enterobacteriace (n = 96) and Pseudomonas spp. (n = 88) from pus samples of hospitalized patients, resistant to 3^rd generation cephalosporins.

Results:

Out of a total of 96 clinical isolates of Enterobacteriaceae, 18.7, 20.8, and 27% were pure ESBL, AmpC, and MBL producers, respectively. ESBL and AmpC were co-produced by 25% isolates. Among 88 Pseudomonas spp. 38.6, 13, and 6% were pure MBL, ESBL, and AmpC producers, respectively. ESBL/AmpC and MBL/AmpC co-production was seen in 20% and 18% isolates, respectively. Among ESBL and AmpC co-producers, CA/CAC/CLOX disc combination (DC) missed 7 of the 24 ESBL producers in Enterobacteriace and 4 of the 18 ESBL in Pseudomonas spp., which were detected by CA/CAT/CLOX DC. No mechanism was detected among 8.3% Enterobacteriaceae and 2.3% Pseudomonas isolates.

Conclusion:

Diagnostic problems posed by co-existence of different classes of β-lactamases in a single isolate could be solved by disc combination method by using simple panel of discs containing CA, CAT, CAT/CLOX, IMP, and IMP/EDTA.