Implementation of the EUCAST rapid antimicrobial susceptibility test (RAST) for carbapenemase/ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates, and its effect on mortality.

OBJECTIVES: With the rise in antimicrobial resistance, there is a growing demand for rapid antimicrobial susceptibility testing (RAST). In this study, we applied the EUCAST RAST method to ESBL/carbapenemase-producing Escherichia coli and Klebsiella pneumoniae isolates without using advanced identification systems and analysed the effect of this method on mortality rates Also the clinical impact of this method on patients infected with these bacteria and its effect on mortality rates were investigated. METHODS: RAST was used for clinical blood cultures containing carbapenemase/ESBL-producing E. coli and K. pneumoniae without advanced identification systems (e.g. MALDI TOF), with preliminary identification by simple diagnostic tests (predicted RAST, or p-RAST), and its categorical agreement was investigated. The impact of the method on mortality was analysed by comparing the clinical data of patients whose blood cultures were subject to p-RAST (p-RAST group, n = 49) and those who were not subject to p-RAST (non-RAST group, n = 145). RESULTS: p-RAST results were analysed based on 539 antibiotic-bacteria combinations. Total error rates at 4, 6 and 8 h of incubation were 2.9%, 3.9% and 3.8%, respectively. In the p-RAST group, patients who did not receive appropriate antibiotics (29/45, 59.1%) were switched to appropriate treatment within 8 h at the latest. In contrast, in the non-RAST group, treatment of patients who received inappropriate antibiotics (79/145, 54.5%) could be changed after at least 24 h. Mortality rates were lower in the p-RAST group than in the non-RAST group (28.6% versus 51.7%, P = 0.005). CONCLUSIONS: p-RAST can be used safely in hospital laboratories with high rates of antimicrobial resistance and can reduce mortality rates by shortening the transition time to appropriate treatment.

Change in Hepatitis B Surface Antibody Titers After Chemotherapy in Patients With Hematological Malignancies.

Background The change in hepatitis B surface antibody (anti-HBs) titers after chemotherapy (CT) in patients with hematological malignancy, affecting factors, and its clinical implications have not been sufficiently understood. Therefore, we aim to evaluate the change in anti-HBs titers and hepatitis B virus reactivation (HBVr) after CT. Methods This retrospective study enrolled patients with hematological malignancies who received CT between 2013 and 2021. All patients were followed up for HBVr and a change in anti-HBs titers for one year. Results Overall, 192 patients were included. In total, 33.9% of the patients were anti-HBs (+) and 26% of the patients were anti-HBc (+) ± anti-HBs (+). Hepatitis B virus (HBV) prophylaxis was given to 35 (70%) of 50 Anti-HBc (+) patients. Tenofovir disoproxil fumarate and entecavir prophylaxis were initiated in 25 (71.4%) and 10 (28.6%) patients, respectively. A significant decrease was found in anti-HBs titers of all patients (p=0.017). A significant decrease was also found in anti-HBs titers of HBc IgG (+) patients and those who received four or more courses of CT (p=0.025; p=0.041). HBVr was not diagnosed in any of the patients. Conclusion Chemotherapeutic agents administered for hematological malignancy have serious immunosuppression effects. In these patients, anti-HBs titers may decrease or become negative one year after CT. Anti-HBs titer before CT or its change after CT may not constitute a risk for HBVr patients who received HBV prophylaxis in line with current guidelines and these recommendations.

Comparative Analysis of Demographic and Clinical Findings in Spontaneous, Peritoneal Dialysis-Related, and Secondary Bacterial Peritonitis.

Background This study aims to contribute to peritonitis management strategies by comparing the demographic, clinical, and laboratory characteristics of patients diagnosed with spontaneous bacterial peritonitis (SBP), peritoneal dialysis-related peritonitis (PDrP), and secondary peritonitis. Methods This study included 86 patients diagnosed with peritonitis between 2016 and 2022. Patients were categorized and compared as SBP, PDrP, and secondary peritonitis. Results SBP was diagnosed in 36% of patients, secondary peritonitis in 36% and PDrP in 28%. The mean age of patients with PDrP is 43.71 ± 14.74, which is significantly lower compared to those with SBP and secondary peritonitis (p<0.001). Patients with hypertension (HT), chronic kidney disease (CKD), and those undergoing dialysis most commonly have PDrP whereas those without HT, without CKD, and not undergoing dialysis are most often diagnosed with secondary peritonitis (p=0.002, p<0.001, p<0.001). In peritoneal fluid cultures, the growth of Gram-positive bacteria was most commonly identified in patients with PDrP, while the growth of Gram-negative bacteria was most frequently seen in patients with secondary peritonitis (p=0.018). CRP levels and sedimentation rates were found to be higher in patients with secondary peritonitis (p<0.001, p=0.003). Conclusion The distinct characteristics observed across different types of peritonitis underscore the importance of tailored approaches to diagnosis and treatment. Parameters such as CRP levels, sedimentation rates, and patient age could serve as valuable indicators in discerning between various types of peritonitis. When selecting empirical antibiotic therapy, it's crucial to consider coverage for Gram-positive pathogens in cases of PDrP and Gram-negative pathogens in secondary peritonitis.

Comparison of the Distribution of Healthcare-Associated Infections and Causative Agents Between Intensive Care Units and Other Clinics.

OBJECTIVE: To compare the trends in the distribution of healthcare associated infectious (HAIs) and causative agents in intensive care units (ICUs) and other clinics. STUDY DESIGN: Descriptive study. Place and Duration of the Study: Department of Infectious Diseases and Clinical Microbiology, Health Sciences University, Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkiye, from 2015 to 2022. METHODOLOGY: The study included patients who were diagnosed with HAIs and admitted to both the ICUs and the clinics. The data of HAIs identified between 2015-2022 were accessed and analysed retrospectively from the surveillance records of the IPC committee between 28.05.2023-07.08.2023. RESULTS: There was a decreasing trend observed in both ICU and clinics regarding the ratio of patients developing HAIs and the overall HAI rate (all p-values <0.001). These two measures were found to be significantly lower in the years 2019-2022 compared to the years 2015-2018. Over the years, particularly after 2020, a significant increasing trend in carbapenem resistance was observed in E. coli, K. pneumoniae, and P. aeruginosa (p=0.009, p<0.001, and p<0.001, respectively). The ratio of patients developing HAIs in the ICUs was higher than in the clinics (p<0.001). There was an increasing trend in the ratio of pneumonia and bloodstream infection (BSI) in ICUs. CONCLUSION: The increasing ratio of BSI and pneumonia in ICUs highlighted the need to review infection control bundles. Carbapenem resistance has been increasing over the years, suggesting that antimicrobial description and consumption practices should be re-evaluated, especially in the context of the COVID-19 pandemic. KEY WORDS: Intensive Care Unit, Healthcare-Associated Infections, Surveillance, Infection prevention and control, Antibiotic resistance.

Gram-Negative Bloodstream Infections in Healthcare: The Relationship Between Antibiotic Resistance, Mortality, and Novel Serological Biomarker.

BACKGROUND: Bloodstream infections caused by Gram-negative bacteria are highly mortal. In this study, we aimed to investigate the relationship between antimicrobial resistance profile and novel serological biomarkers and mortality in bloodstream infections (BSIs) caused by Gram-negative bacteria in intensive care units (ICUs). METHODS: 366 Patients diagnosed with healthcare-associated Gram-negative bloodstream infection in the ICUs of our hospital between February 2015 and December 2021 were included in the study. Demographic variables (age, gender, comorbidities), causative microorganisms and antimicrobial susceptibilities, time to first positive blood culture after hospitalization, length of stay in hospital, surgical procedures, laboratory data (hemograms, C-reactive protein (CRP) levels, albumin), and survival data were collected. Novel serological biomarkers were calculated. RESULTS: Mortality in Gram-negative bloodstream infection was found to be associated with age and novel serological biomarkers, but not with carbapenems and colistin minimum inhibitory concentration (MIC) values. Mortality rates increased with age (p˂0.001). Patients who died had higher C-reactive protein/albumin ratio (CAR) (p<0.001) and neutrophil/lymphocyte ratio (NLR) (p=0.009) and lower prognostic nutritional index (PNI) (p<0.001). CONCLUSION: The study emphasizes that resistance to colistin and carbapenems is not associated with mortality in BSIs caused by Gram-negative bacteria. Novel serological biomarkers may be useful in predicting mortality. These results support the need for further studies to elucidate the true impact of infections caused by resistant bacteria.

Impact of the COVID-19 Pandemic on Diabetic Foot Patients: A Shift in the Infectious Agent Profile Toward Nonfermentative Gram-Negative Bacilli.

BACKGROUND: Diabetes foot infection is a very important public health problem that causes serious health problems, mortality, and high health expenditures, and is one of the most important complications of diabetes mellitus. There are concerns that approaches such as limited personal visits to doctors, avoidance of hospitals, and restrictions on nonemergency surgical procedures during the coronavirus disease of 2019 pandemic pose a threat to those with diabetic foot problems, including diabetic foot ulcers (DFUs), ischemia, and infection, resulting in increased limb loss and mortality. METHODS: This multicenter, retrospective, cross-sectional study was conducted in 14 tertiary care hospitals from various regions of Turkey. A total of 1,394 patient records were evaluated, 794 of which were between January 1, 2019, and January 30, 2020 (prepandemic [Pre-P]), and 605 of which were between February 1, 2020, and February 28, 2021 (pandemic period [PP]). RESULTS: During the PP, diabetic foot patient follow-up decreased by 23.8%. In addition, the number of hospitalizations attributable to DFU has decreased significantly during the PP (P = .035). There was no difference between the groups regarding patient demographics, medical history, DFU severity, biochemical and radiologic findings, or comorbidities, but the mean duration of diabetes mellitus years was longer in patients in the Pre-P than in those in the PP (15.1 years versus 13.7 years). There was no difference between the two groups in terms of major complications such as limb loss and mortality, but infection recurrence was higher in the PP than in the Pre-P (12.9% versus 11.4%; P < .05). The prevalence of nonfermentative gram-negative bacteria as causative agents in DFU infections increased during the PP. In particular, the prevalence of carbapenem-resistant Pseudomonas spp. increased statistically during the PP. CONCLUSIONS: The rapid adaptation to the pandemic with the measures and changes developed by the multidisciplinary diabetic foot care committees may be the reasons why there was no increase in complications because of DFU during the pandemic in Turkey.