Prevalence Of Drug-resistant Pathogens Research Articles

Antimicrobial Hydrogels: Potential Materials for Medical Application.

Microbial infections based on drug-resistant pathogenic organisms following surgery or trauma and uncontrolled bleeding are the main causes of increased mortality from trauma worldwide. The prevalence of drug-resistant pathogens has led to a significant increase in medical costs and poses a great threat to the normal life of people. This is an important issue in the field of biomedicine, and the emergence of new antimicrobial materials hydrogels holds great promise for solving this problem. Hydrogel is an important material with good biocompatibility, water absorption, oxygen permeability, adhesion, degradation, self-healing, corrosion resistance, and controlled release of drugs as well as structural diversity. Bacteria-disturbing hydrogels have important applications in the direction of surgical treatment, wound dressing, medical device coating, and tissue engineering. This paper reviews the classification of antimicrobial hydrogels, the current status of research, and the potential of antimicrobial hydrogels for one application in biomedicine, and analyzes the current research of hydrogels in biomedical applications from five aspects: metal-loaded hydrogels, drug-loaded hydrogels, carbon-material-loaded hydrogels, hydrogels with fixed antimicrobial activity and biological antimicrobial hydrogels, and provides an outlook on the high antimicrobial activity, biodegradability, biocompatibility, injectability, clinical applicability and future development prospects of hydrogels in this field.

2187. Validation of Local Risk Factors for Antibiotic-resistant Pathogens in Community-acquired Pneumonia at an Urban Community-based Medical Center

Abstract Background The 2019 ATS/IDSA community-acquired pneumonia (CAP) guidelines recommend to abandon the term healthcare-associated pneumonia (HCAP) and to base the use of broad-spectrum antibiotics on local epidemiology and risk factors. Jamaica, NY represents a unique population of ethnically diverse, largely immigrant patients. Several nursing homes, an international airport, along with a low socioeconomic status population feed into the hospital. The purpose of this study is to determine prevalent risk factors for drug-resistant pathogens (DRP) in CAP within an urban population. The secondary objective is to validate the Drug Resistance in Pneumonia (DRIP) score in this population. Methods A retrospective study was conducted on adults admitted from August 2018-December 2019 with a diagnosis of CAP, including aspiration pneumonia. Patients with a DRP respiratory culture (collected within 48 hours of admission) were selected, the next consecutively admitted patient with a non-resistant culture was included as a control. Results A total of 227 patients were included (114 in the DRP group and 113 in the control group). The DRP group had more patients with tracheostomies (30% vs 3%, p < .001) and chronic pulmonary disease (37% vs 16%, p < .001) (Table 1). Approximately 40% of the DRP patients were admitted from a long term care (LTC) facility compared to 8.8% in the control group (p < .001). Isolation of P. aeruginosa was not associated with LTC residence (Odds Ratio: 0.75) in our population (Table 2). All DRIP score components were associated with the isolation of DRP in our patient population, except for methicillin-resistant S. aureus (MRSA) colonization (Table 3). In our population 50% of the DRP had a DRIP score < 3. DRIP scores > 2, > 3 and > 4 had low negative predictive values (NPV) for the isolation of DRP in CAP (71.9%, 67.4% and 64.2%, respectively). Conclusion Demographic risk factors may exist for DRP in CAP, e.g. tracheostomy, pulmonary disease. Using a DRIP score cut off of > 4 missed 50% of the DRP in our study population. Despite a DRIP score > 4 having a specificity of 90.3%, with a NPV of 64.2% this scoring tool may underestimate the prevalence of DRP in our patient population. Based on our findings, institutions should consider local validation of the DRIP score prior to implementing use at their site. Disclosures All Authors: No reported disclosures.

Phytochemical screening and antibacterial activity of <i>Centaurea senegalensis</i> growing in Nigeria

The increasing prevalence of drug resistant pathogens in developing countries has necessitated research for effective therapeutic agents from plants. This study was designed to evaluate the antibacterial properties of Centaurea senegalensis and investigate the phytochemical constituents. The plant sample was extracted using methanol and subjected to successive partition with n-hexane, dichloromethane and ethyl acetate. The methanol extract (ME), hexane (HF), dichloromethane (DF) and ethylacetate (EF) fractions were subjected to antibacterial screening on selected gram-positive and gram-negative bacteria using agar well and micro broth dilution methods. The antibacterial efficacies of extracts showed varying zones of growth inhibitions (15-31 mm). The DF fraction was effective on Methicillin resistant Staphylococcus aureus (MRSA), and Vancomycin resistant enterococci (VRE) with interesting activity (28 mm, MIC 12.5 mgmL-1). However, the EF was most effective fraction against gram-negative bacteria such as Escherichia coli (31 mm, MIC, 12.5 mgmL-1). Chemical composition of bioactive fraction was determined using gas chromatography-mass spectrometry (GC-MS). The compounds detected were largely natural acetylenes such as 1, 5-heptadien-3-yne (23.2%), 2-hexyne-1-ol (12.3%), 2-methyl-1,5-hexadien-3-yne (6.6%) and 5-methyl-1-hexyn-3-ol (2.1%) as most abundant phytoconstituents identified. C. senegalensis fractions have demonstrated effective activity on both gram-positive and gram-negative bacteria, which might be attributed to acetylene derived natural compounds. Our findings have shown the importance of C. senegalensis as source of chemical compounds with effective antibacterial properties.Keywords: Centaurea senegalensis, phytochemical screening, antibacterial activity, GC-MS

Regional differences in antibiotic-resistant pathogens in patients with pneumonia: Implications for clinicians.

Antibiotic resistance is of great concern for both infection control and the treatment of infectious diseases. Previous studies reported that the occurrence of drug-resistant pathogens (DRPs)-for instance, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae-were associated with inappropriate antibiotic treatment that resulted in adverse outcomes. In addition, unnecessary use of broad-spectrum antibiotics for patients with non-DRPs increased mortality. Therefore, the assessment of risk for DRPs at diagnosis is critical to avoid patients' adverse events. In the present review, we discuss regional differences in the prevalence of DRPs, which ranged from 6% to 45%, in patients with community-onset pneumonia, including both community-acquired and healthcare-associated pneumonia. We then introduce the reported risk factors for DRPs in those patients, and present proposed prediction models for identifying patients with DRPs at diagnosis. Physicians should be aware that some of the risk factors for DRPs (e.g. prior antibiotic use and prior hospitalization) were common between regions; however, others may be different or the weighting of the risks may vary, even for the same risk factors. Therefore, a specific evaluation of risk factors for DRPs is recommended for each region and institution. Furthermore, we present a possible strategy for initial antibiotic selection in patients with community-onset pneumonia, considering DRPs risk. We also discuss future directions for the study of DRPs in community-onset, hospital-acquired and ventilator-associated pneumonia to improve the management of patients with pneumonia.

Epidemiology and drug resistance profile of acute bacterial meningitis in children in Northern India: a university hospital perspective

ObjectiveTo assess epidemiology, trends in etiology and the antimicrobial sensitivity pattern of the pathogens. MethodsCerebrospinal fluid was collected from 150 patients who were suspected of meningitis and processed according to standard microbiological techniques. Cerebrospinal fluid samples were tested for antigen detection by latex agglutination test (LAT). Antimicrobial sensitivity test was done by Kirby-Bauer disc diffusion method. ResultsFever, abnormal movements and altered sensorium were the most common presenting features. Etiological agents were identified in 79 (53%) cases. A total of 33 (42%) samples were cultured positive while 59 (75%) were positive by LAT. Pneumococcus followed by Gram-negative organisms were the most common pathogens. Mortality was 28 (19%). The aminoglycosides had the best spectrum of antimicrobial activity. An alarming rise of methicillin-resistant Staphylococcus aureus (75%) and extended-spectrum beta-lactamase (59%) was seen. No high-level aminoglycoside resistance, AmpC or mannose-binding lectin production was observed. ConclusionsPneumococcus and Gram-negative pathogens were the most common organisms. High prevalence of drug resistant pathogens is seen. Inclusion of LAT for antigen detection in routine diagnosis adds a valuable adjunct in the rapid and accurate diagnosis of pyogenic meningitis especially in partially treated cases.

Risk factors for drug-resistant bacterial pneumonia in older patients hospitalized with pneumonia in a Chinese population

The relationship between healthcare-associated pneumonia (HCAP) and resistant bacteria is unclear. The aim of this study was to identify the risk factors for pneumonia caused by drug-resistant bacteria (DRB). A prospective cohort study was conducted at a tertiary teaching hospital in Hong Kong. Consecutive older patients (aged ≥65 years) were hospitalized with pneumonia from January 2004 to June 2005. DRB comprised methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae and Acinetobacter baumannii. The entire cohort consisted of 1176 older patients. Of 472 (40.1%) patients with etiological diagnosis established, bacterial pneumonia was found in 354 (30.1%) cases. DRB were isolated in 48 patients: P. aeruginosa (41), MRSA (5) and ESBL producing enteric bacilli (3). Co-infection with P. aeruginosa and MRSA was found in one patient. The prevalence of DRB in culture-positive pneumonia was 20.1% (48/239). Patients with DRB were more likely to have limitation in activities of daily living, bronchiectasis, dementia, severe pneumonia, recent hospitalization and recent antibiotic use. Logistic regression revealed that bronchiectasis [relative risk (RR) 14.12, P = 0.002], recent hospitalization (RR 4.89, P < 0.001) and severe pneumonia (RR 2.42, P = 0.010) were independent predictors of drug-resistant bacterial pneumonia. Recent hospitalization is the only risk factor for HCAP which is shown to be associated with DRB. Nursing home residence is not a risk factor. The concept of HCAP may not be totally applicable in Hong Kong where the prevalence of drug-resistant pathogens in pneumonia is low.

Clinical Scoring for Risk of Resistant Organisms in Pneumonia: Right Idea, Wrong Interpretation

To the Editor—In their recent article, Shorr and colleagues present a new clinical tool to predict risk of drug-resistant bacterial pneumonia in patients presenting to emergency departments [1]. Improving risk assessment and minimizing inappropriate antibiotic use are necessary given the increasing prevalence of resistant pathogens and the risk of selecting for further resistance through overuse of broad-spectrum antibiotics, but this new risk score has several weaknesses. A weighted risk score is an attractive strategy to improve clinical decision making, but the authors overstate its advantages over the existing healthcare-associated pneumonia (HCAP) definition. Although the authors assert that their new risk score is superior to HCAP criteria because it incorporates weighting of risk factors, the cutoff of 0 turns the risk score into a dichotomous tool by which the presence of any risk factor yields a score considered positive rather than a stratified risk score. Under this conclusion, the predictive ability of the new tool is comparable (but not superior) to the current HCAP definition. Using a dichotomous risk tool ignores the information contained in a scoring system, and such a tool cannot be compared directly with the HCAP criteria. To compare the two, cutoff points should be contrasted for persons meeting 1, 2, or more HCAP or risk score criteria. The authors could further improve the predictive ability of their score by presenting likelihood ratios for each of the risk scores of the new tool. The authors present single positive and negative predictive values based on a risk score of 0, but these statistics could be calculated for other scores as well. Because of the effect of prevalence on the performance of diagnostic tests, we are concerned that the prevalence of drug-resistant pathogens reported in the study is inaccurate due to verification bias that occurs when the action of performing a test is affected by the pretest probability of disease [2]. The authors report a 47% prevalence of drug-resistant pathogens, likely an overestimation. A medical history suggesting a person had high risk for drug-resistant bacterial infection might influence physicians’ decisions to obtain cultures, a criterion for inclusion in the study. Persons without significant healthcare exposure might be deemed low-risk by clinicians, who would not order cultures, leading to underrepresentation of these patients in this study. Verification bias results in overestimation of the sensitivity and underestimation of the specificity of the new risk score. Unfortunately it is difficult to confirm that verification bias has occurred; however, the authors could have performed sensitivity analyses or controlled for culture collection to assess this problem. Finally, the most appropriate cutoff for risk score is determined by weighing the costs of further testing or broad-spectrum antibiotic use in patients who do not need them against benefits of appropriate early therapy in those infected with drug-resistant pathogens. This balance will depend on the clinical characteristics and risk factors of the patients, societal views of medical care, and economic considerations. Although the HCAP definition reaches an imperfect balance, the authors’ clinical risk score fails to improve upon that standard.

Antibiotic Resistance Among Genital Tract Isolates from Sexually-Transimitted Disease Patients

A retrospective study of 974 genital tract pathogens isolated from sexually-transmitted disease (STD) patients was carried out at the University of Benin Teaching Hospital (UBTH), Benin City, between February 2001 and September 2003. The isolates which were associated with 22 cases of gonorrhoea, 271 cases of non-gonococcal urethritis (NGU) and 681 of pelvic inflammatory disease (PID) comprised Staphylococcus aureus (579), Escherichia coli (220), Klebsiella spp. (199), Proteus spp. (54) and Neisseria gonorrhoeae (22). The lack of appropriate diagnostic procedures precluded the investigation of the involvement of chlamydiae and mycoplasma in these infections. The susceptibility of bacterial isolates to new-quinolones and other antibacterial agents was determined by the use of multi-disc diffusion method. Most isolates were susceptible to ofloxacin, ciprofloxacin and perfloxacin, while most isolates were resistant to ampicillin, chloramphenicol, cotrimoxazole and streptomycin. The results of the susceptibility pattern shows that there is still a rise in the prevalence of drug-resistant pathogens in our hospitals. This could be due to inappropriate therapeutic use of antimicrobials such as unprescribed use of broad spectrum antibiotics against causative microbial agents for which antibiogram profiles had not been determined. Keywords: Antibiotic resistance, genital tract isolates Journal of Medical Laboratory Sciences Vol. 14 (1) 2005: pp. 63-68