Frequency of microbial isolates and pattern of antimicrobial resistance in patients with hematological malignancies: a cross-sectional study from Palestine

Antimicrobial resistance profiles of Escherichia coli isolated from clinical and environmental samples: findings and implications

Background

The overuse and misuse of antimicrobials has worsened the problem of antimicrobial resistance (AMR) globally. This study investigated the AMR profiles of Escherichia coli isolated from clinical and environmental samples in Lusaka, Zambia.

Methods

This was a cross-sectional study conducted from February 2023 to June 2023 using 450 samples. VITEK® 2 Compact was used to identify E. coli and perform antimicrobial susceptibility testing. Data analysis was done using WHONET 2022 and SPSS version 25.0.

Results

Of the 450 samples, 66.7% (n = 300) were clinical samples, whereas 33.3% (n = 150) were environmental samples. Overall, 47.8% (n = 215) (37.8% clinical and 10% environmental) tested positive for E. coli. Of the 215 E. coli isolates, 66.5% were MDR and 42.8% were ESBL-producers. Most isolates were resistant to ampicillin (81.4%), sulfamethoxazole/trimethoprim (70.7%), ciprofloxacin (67.9%), levofloxacin (64.6%), ceftriaxone (62.3%) and cefuroxime (62%). Intriguingly, E. coli isolates were highly susceptible to amikacin (100%), imipenem (99.5%), nitrofurantoin (89.3%), ceftolozane/tazobactam (82%) and gentamicin (72.1%).

Conclusions

This study found a high resistance of E. coli to some antibiotics that are commonly used in humans. The isolation of MDR and ESBL-producing E. coli is a public health concern and requires urgent action. Therefore, there is a need to instigate and strengthen interventional strategies including antimicrobial stewardship programmes to combat AMR in Zambia.

Epidemiology and clinical characteristics of patients with healthcare-acquired multidrug-resistant Gram-negative bacilli: a retrospective study from a tertiary care hospital

The numbers of infections caused by Gram-negative bacteria (GNB) that produce extended-spectrum beta-lactamases (ESBLs) and those that are carbapenem resistant, especially Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae), are increasing, and these infections are becoming a global public health problem. The aim of this study was to assess the prevalence of infections caused by ESBL-producing and carbapenem-resistant Gram-negative bacilli in patients hospitalized at An-Najah National University Hospital in Nablus, Palestine, and to provide healthcare workers with valuable information on the treatment of these infections. A retrospective cross-sectional investigation was conducted at a large tertiary care teaching hospital. The study included patients admitted to the hospital between January and December 2021, from whom ESBL-producing and carbapenem-resistant Gram-negative bacilli were isolated. The patients' clinical and demographic information was obtained from the hospital information system. In addition, information regarding the bacterial isolates and antibiotic resistance was obtained from the hospital's microbiology laboratory. This study included a total of 188 patients-91 males (48.4%) and 97 females (51.6%). The general surgical ward accounted for the highest proportion of infections (30.9%), followed by the surgical ICU (12.2%). The most common infections were caused by ESBL-producing E. coli, which accounted for 62.8% of the cases. Among them, urinary tract infections caused by this microorganism were the most prevalent (44.7% of patients). Over 50% of the patients (54.2%) had a history of antibiotic use, and 77.8% had been hospitalized within the past three months. ESBL-producing E. coli was significantly isolated from blood cultures (p-value = 0.000), and CR-K. pneumoniae was significantly isolated from endotracheal isolates (p-value = 0.001). This study emphasizes the concerning frequency of healthcare-acquired infections caused by ESBL-producing and carbapenem-resistant GNB in a tertiary care hospital. The substantial prevalence of antibiotic resistance presents considerable obstacles to the successful administration of routinely employed antibiotics. The results highlight the immediate need for improved antimicrobial stewardship and the implementation of infection control strategies to reduce the effects of multidrug-resistant GNB on patient well-being and public health.

Antibiotic resistance profiles and associated factors of Pseudomonas Infections among patients admitted to large tertiary care hospital from a developing country

BACKGROUND

Pseudomonas infections are among the most common infections encountered in hospitalized patients, especially those with chronic illnesses or an immunocompromised state. Management of these infections has become challenging due to increased antibiotic resistance. Therefore, this study examines the antibiotic resistance profiles of Pseudomonas spp. and the associated factors among patients admitted to a large tertiary hospital in a developing country.

METHODS

This retrospective observational chart review study assessed patients admitted to a large tertiary hospital in a developing country with a positive culture growth of Pseudomonas from anybody site. Antibiotic susceptibility of the isolated Pseudomonas and patient characteristics were studied from the start of 2021 to the end of 2022. The study ground consisted of 185 patients.

RESULTS

The study included 185 patients with positive Pseudomonas isolates. Males constituted 54.6% of the sample, while 45.4% were females. The median age of the patients was 53 years. Patient comorbidities and risk factors for Pseudomonas infection and multidrug resistance were assessed. Antibiotic resistance to the Pseudomonas regimens showed the highest resistance to meropenem and ciprofloxacin (23.4%, similarly) among isolates of Pseudomonas aeruginosa. Multidrug resistance (MDR) was found in 108 (58.4%) isolates. The most commonly used antibiotic for treatment was piperacillin-tazobactam, accounting for 33.3% of cases, followed by aminoglycosides at 26.6%.

CONCLUSIONS

Pseudomonas aeruginosa isolates were resistant to meropenem and ciprofloxacin. Over half of the isolates were multidrug-resistant, which was worrying. Piperacillin-tazobactam and aminoglycosides were the most often utilized antibiotics, highlighting the significance of susceptibility testing. Implementing antimicrobial stewardship programs and infection control measures can help reduce drug resistance and improve outcomes in Pseudomonas infections.

[Value of metagenomic next-generation sequencing in children with hematological malignancies complicated with infections]

OBJECTIVES

To explore the value of metagenomic next-generation sequencing (mNGS) in the pathogen identification in children with hematological malignancies complicated with infections.

METHODS

A retrospective analysis was conducted on clinical data and pathogenic test results of 43 children with hematological malignancies who underwent microbial culture and mNGS due to infections in the Third Xiangya Hospital of Central South University between June 2020 and July 2022. Differences in detection rates and characteristics of pathogenic microorganisms detected by mNGS and microbial culture were compared.

RESULTS

A total of 54 specimens were examined, and the overall detection rate of pathogen by mNGS (80%, 43/54) was significantly higher than that by microbial culture (30%, 16/54) (P<0.001). The most commonly detected infection type by mNGS was viral infection, followed by fungal infection combined viral infection, while that by microbial culture was bacterial infection, followed by fungal infection. The detection rate of fungi by mNGS (33%, 18/54) was higher than that by microbial culture (6%, 3/54) (P<0.001). The detection rate of two or more pathogenic microorganisms by mNGS was higher at 48% compared to microbial culture at 9% (P<0.05). The detection rate of two or more types of pathogenic microorganisms by mNGS was also significantly higher at 33% compared to microbial culture at 2% (P<0.05). The most commonly detected bacteria and fungi by mNGS were Pseudomonas aeruginosa and Candida tropicalis, respectively, in peripheral blood, while Streptococcus pneumoniae and Pneumocystis jirovecii were most commonly detected in bronchoalveolar lavage fluid. Treatment adjustments based on mNGS results were beneficial for 35% (15/43) of the cases.

CONCLUSIONS

mNGS has a higher detection rate than microbial culture and has obvious advantages in diagnosing mixed and fungal infections, making it a useful supplementary diagnostic method to microbial culture.

Impact of an antibiotic stewardship program on antibiotic utilization, bacterial susceptibilities, and cost of antibiotics

Antimicrobial misuse is a worldwide issue, and antimicrobial resistance is considered the most challenging aspect of health care. It has been reported that as much as 30-50% of antimicrobials prescribed in hospitals are deemed unnecessary or inappropriate. Antibiotic stewardship programs (ASPs) include policies that apply continuous management of judicious anti-infectious treatment in the clinical setting. Therefore, the objectives of this study were to evaluate the effect of ASPs on antibiotic consumption, the costs of antibiotic expenditure, and the sensitivity of antimicrobials. A retrospective, quasi-experimental study was performed to assess the effect of ASP at An-Najah National University Hospital, a tertiary care hospital in the West Bank, Palestine, over a period of 20 months before and 17 months after the implementation of the ASP. Data on antibiotic consumption were reported monthly as days of therapy per 1000 patient-days and monthly costs (USD/1000 patient-days). A total of 2367 patients who received one or more of the targeted antibiotics (meropenem, colistin and tigecycline) during their hospital stay were included in the study. They have split into two groups: 1710 patients in the pre-ASP group, and 657 patients in the post ASP group. The most significant reduction in DOT per 1000 patient-days was seen with tigecycline, with a percentage of change of - 62.08%. Furthermore, the mean cost of the three antibiotics decreased significantly by 55.5% in the post-ASP phase compared to the pre-ASP phase. After the implementation of ASP, there was a statistically significant increase in susceptibility to meropenem, piperacillin and piperacillin/tazobactam with respect to Pseudomonas aeruginosa. However, changes in mortality rates were not statistically significant (p = 0.057). ASP positively reduced costs and antimicrobial consumption, with no statistically significant effect on the overall mortality rate. However, a long-term evaluation of the ASP's impact is needed to conclude its lasting impact on infection-related mortality and antimicrobial susceptibility pattern.

Epidemiology and source of infection in cancer patients with febrile neutropenia: an experience from a developing country

BACKGROUND

Febrile neutropenia (FN) is a life-threatening complication that predisposes cancer patients to serious infections. This study aims to describe the epidemiology and source of infection in cancer patients with FN in a tertiary care hospital.

METHODS

A hospital-based retrospective study was conducted in a large tertiary care hospital from January 2020 to December 2021. Data on cancer patients with FN were collected from the hospital information system.

RESULTS

150 cancer patients with FN were identified during the study period. Most patients were males (98; 65.3%), and the mean age of participants was 42.2 ± 16.0 years. Most patients (127; 84.7%) had hematologic malignancies, and acute myeloid leukemia was the most common diagnosis (42; 28%), followed by acute lymphocytic leukemia (28; 18.7%) and Hodgkin's lymphoma (20; 13.3%). Fifty-four (36%) patients had a median Multinational Association for Supportive Care in Cancer (MASCC) scores greater than 21. Regarding the outcome, nine (6%) died, and 141(94%) were discharged. The focus of fever was unknown in most patients (108; 72%). Among the known origins of fever were colitis (12; 8%), pneumonia (8; 5.3%), cellulitis (6; 4%), bloodstream infections (7; 4.6%), perianal abscess (2; 1.3%) and others. The median duration of fever was two days, and the median duration of neutropenia was seven days. Sixty-three (42%) patients had infections: 56 (73.3%) were bacterial, four (2.6%) were viral, two (1%) were fungal and 1 (0.7%) was parasitic. Among the bacterial causes, 50 cases (89.2%) were culture-positive. Among the culture-positive cases, 34 (68%) were gram-positive and 22 (44%) were gram-negative. The most frequent gram-positive bacteria were E. faecalis (9; 18% of culture-positive cases), and the most frequent gram-negative organisms were Klebsiella pneumoniae (5; 10%). Levofloxacin was the most commonly used prophylactic antibiotic (23; 15.33%), followed by acyclovir (1610.7%) and fluconazole in 15 patients (10%). Amikacin was the most popular empiric therapy, followed by piperacillin/tazobactam (74; 49.3%), ceftazidime (70; 46.7%), and vancomycin (63; 42%). One-third of E. faecalis isolates were resistant to ampicillin. Approximately two-thirds of Klebsiella pneumoniae isolates were resistant to piperacillin/tazobactam and ceftazidime. Amikacin resistance was proven in 20% of isolates.

CONCLUSIONS

The majority of patients suffered from hematologic malignancies. Less than half of the patients had infections, and the majority were bacterial. Gram-positive bacteria comprised two-thirds of cases. Therefore, empiric therapy was appropriate and in accordance with the antibiogram of the isolated bacteria.

Prediction of Multiple Clinical Complications in Cancer Patients to Ensure Hospital Preparedness and Improved Cancer Care

Reliable and rapid medical diagnosis is the cornerstone for improving the survival rate and quality of life of cancer patients. The problem of clinical decision-making pertaining to the management of patients with hematologic cancer is multifaceted and intricate due to the risk of therapy-induced myelosuppression, multiple infections, and febrile neutropenia (FN). Myelosuppression due to treatment increases the risk of sepsis and mortality in hematological cancer patients with febrile neutropenia. A high prevalence of multidrug-resistant organisms is also noted in such patients, which implies that these patients are left with limited or no-treatment options amidst severe health complications. Hence, early screening of patients for such organisms in their bodies is vital to enable hospital preparedness, curtail the spread to other weak patients in hospitals, and limit community outbreaks. Even though predictive models for sepsis and mortality exist, no model has been suggested for the prediction of multidrug-resistant organisms in hematological cancer patients with febrile neutropenia. Hence, for predicting three critical clinical complications, such as sepsis, the presence of multidrug-resistant organisms, and mortality, from the data available from medical records, we used 1166 febrile neutropenia episodes reported in 513 patients. The XGboost algorithm is suggested from 10-fold cross-validation on 6 candidate models. Other highlights are (1) a novel set of easily available features for the prediction of the aforementioned clinical complications and (2) the use of data augmentation methods and model-scoring-based hyperparameter tuning to address the problem of class disproportionality, a common challenge in medical datasets and often the reason behind poor event prediction rate of various predictive models reported so far. The proposed model depicts improved recall and AUC (area under the curve) for sepsis (recall = 98%, AUC = 0.85), multidrug-resistant organism (recall = 96%, AUC = 0.91), and mortality (recall = 86%, AUC = 0.88) prediction. Our results encourage the need to popularize artificial intelligence-based devices to support clinical decision-making.