Battle of polymyxin induced nephrotoxicity: Polymyxin B versus colistin

OBJECTIVES

Nephrotoxicity is the most serious and common adverse effect that limits the use of polymyxins. This study compared polymyxin E (colistin) and polymyxin B regarding drug-related nephrotoxicity.

METHODS

This study was conducted as a retrospective cohort study in a university hospital between January 2020 and July 2022. Patients older than 18 years and who received colistin or polymyxin B were identified using electronic hospital records. Kidney disease improving global outcome criteria were used for assessing nephrotoxicity.

RESULTS

A total of 190 patients, 95 in both groups, were evaluated. The incidence of acute kidney injury during the treatment was higher in the colistin group [52.6% (n = 50) and 34.7% (n = 33), P = 0.013]. In patients who were exposed to high-dose, the rate of nephrotoxicity was higher in patients receiving colistin [25% (n = 3) vs. 76.9% (n = 10); P = 0.017]. Nephrotoxicity was reversible in 64.4% (n = 38) of patients and the reversibility rate was similar (70% and 52.6% for colistin and polymyxin; P = 0.248). In the multivariable analysis, colistin treatment [odds ratio (OR): 3.882, 95% confidence interval (95% CI) = (1.829-8.241)], concomitant vasopressor use (OR = 2.08, CI: 1.036-4.179), and age (OR=1.036, CI: 1.014-1.058) were found to be independent markers of nephrotoxicity.

CONCLUSION

Nephrotoxicity was more common in patients receiving high-dose colistin than polymyxin B. Therefore, the use of appropriate doses of colistin is important in terms of preventing nephrotoxicity. In addition, advancing age and concomitant use of vasopressors contribute to polymyxin-related nephrotoxicity.

Does marking as sterile mean really sterile? Stenotrophomonas maltophilia outbreak caused by a blood-gas injector containing liquid heparin

An outbreak investigation was initiated after detecting an increase in the number of patients with Stenotrophomonas maltophilia bloodstream infections (SM-BSIs) througout the hospital. S. maltophilia was isolated from the cultures of blood-gas ınjectors containing liquid heparin. The incidence density of SM-BSIs decreased significantly after prohibiting the use of those injectors.

Cessation of Rectal Screening for Vancomycin-Resistant Enterococci: Experience from a Tertiary Care Hospital from Türkiye

OBJECTIVE

Here, we compared the impact of different polices on the epidemiology of Vancomycin-resistant Enterococcus faecium bloodstream infections (VRE-BSIs) in a tertiary care hospital including two hospital buildings (oncology and adult hospitals) in the same campus.

MATERIAL AND METHODS

All patients who were hospitalized in high-risk units were screened weekly for VRE colonization via rectal swab between January 2006 and January 2013. After January 2013, VRE screening was only performed in cases of suspicion of VRE outbreak and during point prevalence studies to evaluate the epidemiology of VRE colonization. Contact precautions were in place for all VRE-positive patients. The incidence density rates of hospital-acquired (HA)-VRE-BSIs were compared between two periods.

RESULTS

While the rate of VRE colonization was higher in the second period (5% vs. 9.5% (p < 0.01) for the adult hospital, and 6.4% vs. 12% (p = 0.02 for the oncology hospital), there was no increase in the incidence rate HA-VRE BSIs after the cessation of routine rectal screening in either of the hospitals.

CONCLUSION

Screening policies should be dynamic and individualized according to the epidemiology of VRE as well as the workforce and cost. Periodical rectal screening of VRE can be discontinued if suspicion of an outbreak can be carefully monitored.

Risk of infection in patients with hematological malignancies receiving CAR T-cell therapy: systematic review and meta-analysis

BACKGROUND

Chimeric antigen receptor (CAR) T-cell therapy has emerged as a promising treatment option for relapsed or refractory B-cell malignancies and multiple myeloma. Underlying and treatment-related variables may contribute to the development of infectious complications.

RESEARCH DESIGN AND METHODS

We conducted a systematic review and meta-analysis on the incidence of overall and severe (grade ≥3) infection in patients with hematological malignancies receiving CAR T-cells. Secondary outcomes included the specific rates of bacterial, viral and invasive fungal infection (IFI), and infection-related mortality. PubMed, Embase and Web of Science databases were searched from inception to 27 May 2022. Sensitivity analysis were performed according to the type of malignancy and study design (randomized clinical trials [RCTs] or observational studies).

RESULTS

Forty-five studies (34 RCTs) comprising 3,591 patients were included. The pooled incidence rates of overall and severe infection were 33.8% (I² = 96.31%) and 16.2% (I² = 74.41%). The respiratory tract was the most common site of infection. Most events were bacterial or viral, whereas the occurrence of IFI was rare. The pooled attributable mortality was 1.8% (I² = 43.44%).

CONCLUSIONS

Infection is a frequent adverse event in patients receiving CAR T-cell therapy. Further research should address specific risk factors in this population.

The impact of COVID-19 pandemic on nosocomial multidrug-resistant bacterial bloodstream infections and antibiotic consumption in a tertiary care hospital

We investigated the change in the epidemiology of nosocomial bloodstream infections (BSIs) caused by multidrug-resistant bacteria during Coronavirus Disease (COVID-19) and antibiotic consumption rates at a pandemic hospital and at the Oncology Hospital which operated as COVID-19-free on the same university campus. Significant increases in the infection density rate (IDRs) of BSIs caused by carbapenem-resistant Acinetobacter baumannii (CRAB) and ampicillin-resistant Enterococcus faecium (ARE) were detected at the pandemic hospital, whereas carbapenem-resistant Klebsiella pneumoniae BSIs were increased at the non-pandemic Oncology Hospital. Pulsed field gel electrophoresis showed a polyclonal outbreak of CRAB in COVID-19 intensive care units. Antibiotic consumption rates were increased for almost all antibiotics, and was most significant for meropenem at both of the hospitals. Increased IDRs of CRAB and ARE BSIs as well as an increased consumption rate of broad-spectrum antibiotics emphasize the importance of a multimodal infection prevention strategy combined with an active antibiotic stewardship program.

PERFORMANCE EVALUATION OF SIX DIFFERENT SARS-CoV-2 ANTIBODY IMMUNOASSAYS: DISEASE SEVERITY AND SERUM SAMPLING TIME AFFECT THE SENSITIVITY

Comparative validation data and clinical performance data are essential for the reliable interpretation of SARS-CoV-2 antibody test results. This study aimed to assess the performance of six SARS-CoV-2 IgG immunoassays in different disease severity settings. Four automated chemiluminescence immunoassays Access (Beckman Coulter), Architect (Abbott), Atellica-IM (Siemens) and Elecsys (Roche) and two ELISA assays (SARS-CoV-2 IgG-S1-based and NCP IgG, Euroimmun) were evaluated in 143 patients and 50 pre-pandemic control sera. Accuracy and precision tests were performed for validation. Overall sensitivity differed between 73.38-88.65%, being higher in spike protein-based assays. Specificity was ≥ 98% in all immunoassays. IgG response was lower for the samples taken <20 days post-symptom onset (87.30%) than for the samples taken ≥20 days post-symptom onset (94.80%). Higher rate of antibody was detected in the clinically moderate disease group. In the asymptomatic and mild group more antibody positivity was detected with spike protein-based assays. Clinical performance of the immunoassays differs according to disease severity and antigen targeted; moderate disease leading to highest rate of IgG response. All the assays tested were eligible for the detection of SARS-CoV-2 IgG however, spike-based assays revealed relatively higher sensitivity than the nucleoprotein-based assays particularly in the asymptomatic and mild disease severity.

Pulmonary nocardiosis caused by Nocardia abscessus mimicking pulmonary thromboembolism in a patient with atypical anti-glomerular basement membrane glomerulonephritis

Nocardia species are opportunistic bacteria that are frequently contagious by inhalation. Recently, Nocardia abscessus has been described as a different species. We report a 54-year-old male who presented with acute pleuritic chest pain, mimicking pulmonary thromboembolism on the 5th day of discharge from the hospital. The patient was receiving immunosuppressive therapy for newly diagnosed atypical anti-glomerular basement membrane disease. Thorax computed tomography revealed a 17x19 mm soft tissue lesion in the lateral segment of the middle lobe of the right lung. After further examinations, a biopsy decision was made and Nocardia abscessus was isolated in the aerobic culture of the aspiration material.

[SARS-CoV-2 Seroprevalence Among Healthcare Workers: Retrospective Analysis of the Data From A University Hospital in Turkey]

COVID-19 infection caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) continues to affect people as a global threat, and the number of cases is increasing every day. Healthcare workers who face potential COVID-19 exposure are at high risk of SARS-CoV-2 transmission. Estimating the prevalence of infection among healthcare professionals, determining the related risk factors and applying effective infection control measures are essential for the continuity of the health system. The aim of this study was to investigate the seroprevalence of SARS-CoV-2 among healthcare workers in our hospital who have participated extensively in the monitoring of COVID-19 patients. In the study, the anti-SARS-CoV-2 IgG antibody test results of 774 healthcare workers between March 24, 2020, and September 10, 2020 were analyzed retrospectively. Age, sex, profession, and the status of being diagnosed with COVID-19 before the antibody test were determined for the healthcare workers in the study. When the anti-SARS-CoV-2 IgG antibody results were evaluated, it was determined that 57 healthcare workers were positive, 708 healthcare workers were negative, and 9 healthcare workers were borderline. The seroprevalence among the workers of our hospital was found to be 7.4%. The antibody positivity rate was 75.6% in individuals diagnosed with COVID-19 by SARS-CoV-2 PCR (polymerase chain reaction) and/or thoracic computed tomography and it was found to be 3.5% in individuals without the diagnosis. The semi-quantitative antibody index values of the healthcare workers who were seropositive and diagnosed with COVID-19 before the test (n= 31) and those who did not (n= 26) were statistically compared and a significant difference was found between the two groups (p<0.01). In our study, the highest seropositivity was observed among residents (12.3%) and among nurses (11.1%), respectively. When the seropositivity rates of the residents and the nurses were compared with other occupational groups, the differences were found to be statistically significant (p= 0.04, p= 0.04, respectively). In conclusion, the seroprevalence of SARS-CoV-2 was determined as 7.4% among healthcare workers in a tertiary hospital with high patient admissions during the COVID-19 pandemic. Considering that SARS-CoV-2 seroprevalence was announced as 0.81% in the press release made by the Ministry of Health of Turkey in July 2020, it is seen that the rate of seroprevalence among health care workers is significantly larger than the community. Determination of the seroprevalence in the general population and large-scale studies are needed for risk assessment in healthcare professionals.

The clinical course of COVID-19 in hematopoietic stem cell transplantation (HSCT) recipients

Background/aim

The disease caused by SARS-CoV-2 was named as COVID-19. There is as yet insufficient information about the effects of HSCT on the clinical course of COVID-19. In the present study, we aimed to investigate the clinical course of COVID-19 in patients who had undergone HSCT.

Materials and methods

We analyzed baseline characteristics, clinical course and findings of COVID-19, hospitalization and death rates, overall survival, and case fatality rates of HSCT recipients diagnosed with COVID-19 retrospectively.

Results

57.6% of the patients underwent AHSCT, and 42.4% underwent allo-HSCT. 60.6%, 27.3%, and 12.1% of the patients had mild, moderate, and severe COVID-19 or critical illness, respectively. Overall, 45.5% were hospitalized, 12.1% required intensive care, and 9.1% necessitated invasive mechanical ventilation. The total CFR was 9.1% in HSCT recipients, 22.2% in patients with active hematologic malignancy, and 4.2% in patients without active hematologic malignancy.

Conclusion

It can be concluded that mortality of HSCT recipients is lower in patients whose primary disease is in remission compared to ones that are not in remission. Further studies with larger group patients are needed in order to delineate the effects of COVID-19 on HSCT patients.