OBJECTIVE

To determine the prevalence of rectal colonization with carbapenem-resistant organisms (CRO) among PGH neonatal intensive care unit (NICU) patients.

A prospective single-center observational study conducted over a 1-month period included all NICU 3 and cohort area patients admitted on April 24, 2024. Rectal swabs were collected for multidrug-resistant organism (MDRO) screening and repeated weekly for 1 month while admitted. Swabs were inoculated on chromogenic media, and isolates were identified and tested for antimicrobial sensitivity by disk diffusion. Clinical characteristics and outcomes were collected for 30 days from initial MDRO screening. Descriptive statistics were used to summarize the data.

The point prevalence of CRO colonization was 37% (14 of 38) at initial screening. There were 14 incident colonizations, hence the 4-week period prevalence of CRO colonization was 72.5% (29 of 40). The patients were mostly very preterm, very low birth weight neonates, majority were tested within the first 2 weeks of life, and half were exposed to meropenem at initial screening. Nosocomial infection developed in 29% and 64%, and 30-day mortality rate was 8% and 21% among initially non-CRO-colonized and CRO-colonized patients respectively. Despite high CRO colonization, no culture-proven CRO infection was observed. Surveillance screening documented persistent CRO colonization in 37%, but no decolonization. Escherichia coli, Klebsiella spp. and Serratia spp. were the most common colonizers.

The high prevalence of rectal CRO colonization in the NICU emphasizes the burden of antimicrobial resistance, but despite the high CRO colonization, no CRO infection was documented from the limited sample and study period.

BACKGROUND AND OBJECTIVE

Antimicrobial resistance (AMR) is a leading global public health concern as it resulted in more difficult-to-treat infections and fatalities. In the Philippines, drug-resistant E. coli, including multidrug-resistant (MDR), extended-spectrum beta-lactamase (ESBL)-producing, carbapenemase-producing carbapenem-resistant (CP-CR) E. coli, have been isolated from common food animals, increasing the risk of cross-contamination between humans, animals, and the environment. However, there is a lack of data on the distribution of E. coli in chicken meat in public wet markets. This study aims to describe the AMR profile of E. coli in raw chicken meat from retail stalls in a selected wet market in Manila City.

This quantitative descriptive study characterized the AMR profile of E. coli isolated from 25 raw chicken meat samples from a wet market in Manila City. Antimicrobial susceptibility was determined through disk diffusion method against 23 antimicrobial agents in 16 antimicrobial classes. MDR E. coli were identified based on the resistance patterns. ESBL- and carbapenemase-producing capacities of the bacteria were tested through double disk synergy test and modified carbapenem inactivation method, respectively.

Twenty-four out of 25 (96%) chicken samples contained E. coli isolates. Of these, 23 (96%) were classified as MDR. High resistance rates were observed against ampicillin (92%), tetracycline (88%), trimethoprim-sulfamethoxazole (83%), chloramphenicol (79%), ampicillin-sulbactam (75%), amoxicillin-clavulanic acid (67%), fosfomycin (67%), and streptomycin (54%). The majority of the E. coli isolates were still susceptible to a wide range of selected antimicrobial agents, including carbapenems (100%), ceftriaxone (100%), cefepime (100%), cefuroxime (96%), cefotaxime (96%), ceftazidime (96%), piperacillin-tazobactam (96%), aztreonam (96%), cefoxitin (92%), and nitrofurantoin (83%), among others. Meanwhile, none of the 24 isolated E. coli samples were classified as ESBL- and CP-CR E. coli.

Among the 25 chicken samples, 24 E. coli colonies were isolated that exhibited 0% to 92% resistance rates against selected antimicrobial agents. Most isolates were classified as MDR, but none were considered ESBLand CP-CR E. coli. This study suggests that chickens in wet markets can potentially serve as reservoir hosts for drugresistance genes, which could transfer to other bacteria and contaminate humans, animals, and the environment within the food production and supply chain. These findings emphasize the need for AMR surveillance and strategies to combat AMR in the Philippines through the One Health approach.

Background and Objective: Antimicrobial resistance (AMR) is a leading global public health concern as it resulted in more difficult-to-treat infections and fatalities. In the Philippines, drug-resistant E. coli, including multidrug-resistant (MDR), extended-spectrum beta-lactamase (ESBL)-producing, carbapenemase-producing carbapenem-resistant (CP-CR) E. coli, have been isolated from common food animals, increasing the risk of cross-contamination between humans, animals, and the environment. However, there is a lack of data on the distribution of E. coli in chicken meat in public wet markets. This study aims to describe the AMR profile of E. coli in raw chicken meat from retail stalls in a selected wet market in Manila City. Methods: This quantitative descriptive study characterized the AMR profile of E. coli isolated from 25 raw chicken meat samples from a wet market in Manila City. Antimicrobial susceptibility was determined through disk diffusion method against 23 antimicrobial agents in 16 antimicrobial classes. MDR E. coli were identified based on the resistance patterns. ESBL- and carbapenemase-producing capacities of the bacteria were tested through double disk synergy test and modified carbapenem inactivation method, respectively. Results: Twenty-four out of 25 (96%) chicken samples contained E. coli isolates. Of these, 23 (96%) were classified as MDR. High resistance rates were observed against ampicillin (92%), tetracycline (88%), trimethoprim-sulfamethoxazole (83%), chloramphenicol (79%), ampicillin-sulbactam (75%), amoxicillin-clavulanic acid (67%), fosfomycin (67%), and streptomycin (54%). The majority of the E. coli isolates were still susceptible to a wide range of selected antimicrobial agents, including carbapenems (100%), ceftriaxone (100%), cefepime (100%), cefuroxime (96%), cefotaxime (96%), ceftazidime (96%), piperacillin-tazobactam (96%), aztreonam (96%), cefoxitin (92%), and nitrofurantoin (83%), among others. Meanwhile, none of the 24 isolated E. coli samples were classified as ESBL- and CP-CR E. coli. Conclusion Among the 25 chicken samples, 24 E. coli colonies were isolated that exhibited 0% to 92% resistance rates against selected antimicrobial agents. Most isolates were classified as MDR, but none were considered ESBLand CP-CR E. coli. This study suggests that chickens in wet markets can potentially serve as reservoir hosts for drugresistance genes, which could transfer to other bacteria and contaminate humans, animals, and the environment within the food production and supply chain. These findings emphasize the need for AMR surveillance and strategies to combat AMR in the Philippines through the One Health approach.
drug resistance ; multi-drug resistance ; drug resistance, multiple ; carbapenemase ; Escherichia coli

OBJECTIVES

The objectives of the study were to determine the antibiotic consumption of restricted antibiotics and to correlate this with resistance rate.

A retrospective review of pharmacy dispensing records was conducted in the adult internal medicine wards of a tertiary level teaching hospital in the Philippines between March 2019 to February 2020. Antibiotic consumption was determined using Defined Daily Dose (DDD) per 1000 patient-days (PD). Correlations between antibiotic consumption and antibiotic resistance of restricted antibiotics were done. Outcomes were compared between Ward 1 (with the presence of a unit-dose pharmacist) and Ward 3 (without a unit-dose pharmacist).

Both wards showed decreasing trends of piperacillin-tazobactam consumption and increasing trends of ceftazidime consumption from quarter 1 to quarter 4. It was observed that levofloxacin was the most prescribed fluoroquinolone with the highest consumption recorded from March to May 2019 in Ward 3 of 350.2 DDD/1000 PD as compared with ciprofloxacin which has the highest consumption (23.3 DDD/1000 PD) during the period June to August 2019 in Ward 1. Antibiotic resistance of Acinetobacter baumannii against ciprofloxacin, levofloxacin, and piperacillin-tazobactam were statistically significantly different between the wards. In Ward 1, ciprofloxacin consumption was strongly positively correlated with Escherichia coli resistance (r = 0.90). In Ward 3, a significantly moderately positive association was observed for ceftazidime consumption and A. baumannii resistance (r = 0.61), positive correlation between piperacillin-tazobactam and E. coli resistance (r = 0.65), and a strong positive correlation in Ward 3 between levofloxacin and Pseudomonas aeruginosa resistance (r = 0.71).

The restriction and pre-authorization strategy of the AMS program has greatly contributed to the decrease in the consumption of almost all restricted antibiotics. This strategy has been helpful in minimizing unnecessary antibiotic use associated with inappropriate drug therapy. The success of the AMS program has been based on the collective efforts of the AMS team with the implementation of hospital policies, such as the AMS program, across the different sites in the hospital in order to achieve optimum patient health outcomes. It was noted that the resistance rates of A. baumannii against ciprofloxacin, levofloxacin, and piperacillin-tazobactam were higher in Ward 3 compared to Ward 1 which makes infections very difficult to treat which may result to prolonged hospital stay, increased health-care costs and increased mortality rate. This study has supported the involvement of pharmacists in the AMS team by conducting auditing activities that promote safe compliance of restricted antibiotic use among patients. Pharmacists can greatly participate on either prospective or retrospective review of antibiotic utilization and analyze trends of antibiotic consumption data to provide feedback to prescribing physicians on prescribing patterns and possible correlation with occurrence of antibiotic resistance.

Humans ; Mycobacterium tuberculosis/genetics* ; Microspheres ; Antitubercular Agents/pharmacology* ; Mutation ; Microbial Sensitivity Tests ; Fluoroquinolones ; Drug Resistance, Bacterial/genetics* ; Tuberculosis, Multidrug-Resistant/microbiology*

OBJECTIVE: To explore the genotyping characteristics of human fecal Escherichia coli( E. coli) and the relationships between antibiotic resistance genes (ARGs) and multidrug resistance (MDR) of E. coli in Miyun District, Beijing, an area with high incidence of infectious diarrheal cases but no related data. METHODS: Over a period of 3 years, 94 E. coli strains were isolated from fecal samples collected from Miyun District Hospital, a surveillance hospital of the National Pathogen Identification Network. The antibiotic susceptibility of the isolates was determined by the broth microdilution method. ARGs, multilocus sequence typing (MLST), and polymorphism trees were analyzed using whole-genome sequencing data (WGS). RESULTS: This study revealed that 68.09% of the isolates had MDR, prevalent and distributed in different clades, with a relatively high rate and low pathogenicity. There was no difference in MDR between the diarrheal (49/70) and healthy groups (15/24). CONCLUSION We developed a random forest (RF) prediction model of TEM.1 + baeR + mphA + mphB + QnrS1 + AAC.3-IId to identify MDR status, highlighting its potential for early resistance identification. The causes of MDR are likely mobile units transmitting the ARGs. In the future, we will continue to strengthen the monitoring of ARGs and MDR, and increase the number of strains to further verify the accuracy of the MDR markers.
Humans ; Escherichia coli/genetics* ; Escherichia coli Infections/epidemiology* ; Multilocus Sequence Typing ; Genotype ; Beijing ; Drug Resistance, Multiple, Bacterial/genetics* ; Anti-Bacterial Agents/pharmacology* ; Diarrhea ; Microbial Sensitivity Tests

Stenotrophomonas species are non-fermentative Gram-negative bacteria that are widely distributed in environment and are highly resistant to numerous antibiotics. Thus, Stenotrophomonas serves as a reservoir of genes encoding antimicrobial resistance (AMR). The detection rate of Stenotrophomonas is rapidly increasing alongside their strengthening intrinsic ability to tolerate a variety of clinical antibiotics. This review illustrated the current genomics advances of antibiotic resistant Stenotrophomonas, highlighting the importance of precise identification and sequence editing. In addition, AMR diversity and transferability have been assessed by the developed bioinformatics tools. However, the working models of AMR in Stenotrophomonas are cryptic and urgently required to be determined. Comparative genomics is envisioned to facilitate the prevention and control of AMR, as well as to gain insights into bacterial adaptability and drug development.
Stenotrophomonas/genetics* ; Drug Resistance, Bacterial/genetics* ; Anti-Bacterial Agents/pharmacology* ; Gram-Negative Bacteria ; Genomics ; Microbial Sensitivity Tests

Objective To analyze the genetic subtypes of human immunodeficiency virus (HIV) and the prevalence of pretreatment drug resistance in the newly reported HIV-infected men in Guangxi. Methods The stratified random sampling method was employed to select the newly reported HIV-infected men aged≥50 years old in 14 cities of Guangxi from January to June in 2020.The pol gene of HIV-1 was amplified by nested reverse transcription polymerase chain reaction and then sequenced.The mutation sites associated with drug resistance and the degree of drug resistance were then analyzed. Results A total of 615 HIV-infected men were included in the study.The genetic subtypes of CRF01_AE,CRF07_BC,and CRF08_BC accounted for 57.4% (353/615),17.1% (105/615),and 22.4% (138/615),respectively.The mutations associated with the resistance to nucleoside reverse transcriptase inhibitors (NRTI),non-nucleoside reverse transcriptase inhibitors (NNRTI),and protease inhibitors occurred in 8 (1.3%),18 (2.9%),and 0 patients,respectively.M184V (0.7%) and K103N (1.8%) were the mutations with the highest occurrence rates for the resistance to NRTIs and NNRTIs,respectively.Twenty-two (3.6%) patients were resistant to at least one type of inhibitors.Specifically,4 (0.7%),14 (2.3%),4 (0.7%),and 0 patients were resistant to NRTIs,NNRTIs,both NRTIs and NNRTIs,and protease inhibitors,respectively.The pretreatment resistance to NNRTIs had much higher frequency than that to NRTIs (2.9% vs.1.3%;χ²=3.929,P=0.047).The prevalence of pretreatment resistance to lamivudine,zidovudine,tenofovir,abacavir,rilpivirine,efavirenz,nevirapine,and lopinavir/ritonavir was 0.8%, 0.3%, 0.7%, 1.0%, 1.3%, 2.8%, 2.9%, and 0, respectively. Conclusions CRF01_AE,CRF07_BC,and CRF08_BC are the three major strains of HIV-infected men≥50 years old newly reported in Guangxi,2020,and the pretreatment drug resistance demonstrates low prevalence.
Male ; Humans ; Middle Aged ; Reverse Transcriptase Inhibitors/therapeutic use* ; HIV Infections/drug therapy* ; Drug Resistance, Viral/genetics* ; China/epidemiology* ; Mutation ; HIV-1/genetics* ; Protease Inhibitors/therapeutic use* ; Genotype

Multiple myeloma(MM)is a systemic malignancy of plasma cells.Nowadays,the basic research on MM is flourishing with the continuous optimization and innovation of mouse models of MM.Heterologous mouse models of MM established with human-derived cells and immunodeficient mice have been applied in assessing drug efficacy,exploring drug resistance mechanisms,and observing tumor-bone marrow microenvironment interactions.In the last decades,the homologous mouse models of MM established with murine-derived cells or gene-editing technologies have been widely used in the research on the pathogenesis and drug development.Additionally,the stable modeling of targeted organ injury will be a key problem to be tackled in this field.This review summarizes the characteristics and application progress of mouse models of MM.
Humans ; Animals ; Mice ; Multiple Myeloma/pathology* ; Bone Marrow/pathology* ; Disease Models, Animal ; Drug Resistance ; Tumor Microenvironment

This study explored the effect and underlying mechanism of Stellera chamaejasme extract(SCE) on multidrug resistance of breast cancer. The chemotherapy-sensitive breast cancer cell line MCF-7 and adriamycin(ADR)-resistant cell line MCF-7/ADR were used as experimental subjects. MTT assay was used to detect cell proliferation activity. Pi staining was used to detect the cell cycle. 4',6-Diamidino-2-phenylindole, dihydrochloride(DAPI) staining and flow cytometry were used to detect apoptosis. Dansylcadaverine(MDC) staining and GFP-LC3B-Mcherry adenovirus transfection were used to detect autophagy. The protein expression of Bcl-2, Bax, caspase-9, caspase-3, LC3B, p62, and Beclin-1 was detected by Western blot. The results showed that SCE could significantly inhibit the proliferation of both sensitive and resistant breast cancer cell lines. The drug resistance factor was 0.53, which was significantly lower than 59 of ADR. Meanwhile, the proportion of sensitive/resistant cells in the G_0/G_1 phase increased significantly after SCE treatment. In addition, DAPI staining showed that a series of apoptosis phenomena such as nuclear pyknosis, staining deepening, and nuclear fragmentation appeared in sensitive/resistant cell lines after SCE administration. Moreover, the results of flow cytometry double staining showed that the proportion of apoptotic cells in sensitive/resistant cell lines increased significantly after SCE administration. Besides, Western blot showed that the protein expression levels of caspase-3, caspase-9, and Bcl-2 significantly decreased and the expression level of Bax protein significantly increased in both breast cancer cell lines after SCE administration. Furthermore, SCE could also increase the positive fluorescent spots after MDC staining and yellow fluorescent spots after GFP-LC3B-mcherry transfection, and up-regulate the expression levels of autophagy-related proteins LC3B-Ⅱ, p62, and Beclin-1 in breast cancer cells. In summary, SCE may play the role of anti-multidrug resistance by blocking the cell cycle of breast cancer multidrug-resistant cells, blocking autophagy flow, and ultimately interfering with the apoptosis resistance of drug-resistant cells.
Humans ; Female ; Breast Neoplasms/metabolism* ; MCF-7 Cells ; Caspase 3/metabolism* ; Caspase 9/metabolism* ; Beclin-1/pharmacology* ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; Cell Proliferation