An evaluation of a Stenotrophomonas maltophilia outbreak due to commercial arterial blood gas collection kit.

BACKGROUND: Stenotrophomonas maltophilia is a gram-negative bacterium that can cause hospital infections and outbreaks within hospitals. This study aimed to evaluate an outbreak of Stenotrophomonas maltophilia, caused by ready-to-use commercial syringes containing liquid lithium and heparin for arterial blood gas collection in a university hospital. METHODS: Upon detecting an increase in Stenotrophomonas maltophilia growth in blood cultures between 15.09.2021 and 19.11.2021, an outbreak analysis and a case-control study (52 patients for the case group, 56 patients for the control group) were performed considering risk factors for bacteremia. Samples from possible foci for bacteremia were also cultured. Growing bacteria were identified by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The genetic linkage and clonal relationship isolates were investigated with pulsed-field gel electrophoresis (PFGE) in the reference laboratory. RESULTS: In the case-control study, the odds ratio for the central venous catheter [3.38 (95% confidence interval [CI]: 1.444, 8.705 ; p = 0.006)], for surgery [3.387 (95% confidence interval [CI]: 1.370, 8.373 ; p = 0.008)] and for arterial blood gas collection history [18.584 (95% confidence interval [CI]:4.086, 84.197; p < 0.001)] were identified as significant risk factors. Stenotrophomonas maltophilia growth was found in ready-to-use commercial syringes used for arterial blood gas collection. Molecular analysis showed that the growths in the samples taken from commercial syringes and the growths from blood cultures were the same. It was decided that the epidemic occurred because the method for sterilization of heparinized liquid preparations were not suitable. After discontinuing the use of the kits with this lot number, the outbreak was brought under control. CONCLUSIONS: According to our results, disposable or sterile medical equipment should be included as a risk factor in outbreak analyses. The method by which injectors containing liquids, such as heparin, are sterilized should be reviewed. Our study also revealed the importance of the cooperation of the infection control team with the microbiology laboratory.

Impact of posaconazole prophylaxis and antifungal treatment on BAL GM performance in hematology malignancy patients with febrile neutropenia: a real life experience.

BACKGROUND: Diagnostic accuracy of galactomannan measurements is highly variable depending on the study population, diagnostic procedures, and treatment procedures. We aimed to evaluate the effect of posaconazole prophylaxis and empiric antifungal treatment upon diagnostic accuracy of GM measurements in bronchoalveolar lavage (BAL), bronchial lavage (BL), and serum in hematological malignancy population. METHODS: Patients hospitalized in a single tertiary care center with hematologic malignancies undergoing fiberoptic bronchoscopy (FOB) with a preliminary diagnosis of IPA were retrospectively included. RESULTS: In all the study population (n = 327), AUC for BAL, BL, and serum GM were as follows: 0.731 [0.666-0.790], 0.869 [0.816-0.912], and 0.610 [0.540-0.676] with BL samples having the best diagnostic value. GM measurements in patients under posaconazole prophylaxis (n = 114) showed similar diagnostic performance. While specificity was similar between patients with and without posaconazole prophylaxis, sensitivity of GM measurements was lower in patients with prophylaxis. Analyses with patient classified according to antifungal treatment at the time of FOB procedure (n = 166) showed a decreased diagnostic accuracy in serum GM and BAL GM measurements related with the duration of treatment. However, BAL, BL, and serum GM measurements presented similar sensitivity and specificity in higher cut-off values in longer durations of antifungal treatment. CONCLUSION: Our study shows that posaconazole prophylaxis and active short-term (3 days) antifungal treatment do not significantly affect overall diagnostic performance of GM measurements in bronchoalveolar lavage and bronchial lavage samples. However, using different cut-off values for patients receiving active treatment might be suggested to increase sensitivity.

Tocilizumab treatment in COVID-19: A prognostic study using propensity score matching.

BACKGROUND: The potential role of interleukin-6 (IL-6) in coronavirus disease 2019 (COVID-19) pneumonia provides the rationale for investigating IL-6 signaling inhibitors. OBJECTIVES: To evaluate and report treatment responses to tocilizumab (TCZ) in COVID-19 patients and compare mortality outcomes with those of standard care. MATERIAL AND METHODS: Patients hospitalized with a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, diagnosed with reverse transcription polymerase chain reaction (RT-PCR) between March 2020 and April 2021, were enrolled in this single-center retrospective cohort study. Propensity score matching was performed in order to reduce confounding effects secondary to imbalances in receiving TCZ treatment. RESULTS: A total of 364 patients were included in this study. Two hundred thirty-six patients received standard care, while 128 patients were treated with TCZ in addition to standard care (26 (20.3%) patients received a dose of 400 mg intravenously once, while 102 (79.7%) patients received a total dose of 800 mg intravenously). In the propensity score-matched population, less noninvasive mechanical ventilation (p = 0.041) and mechanical ventilation support (p = 0.015), and fewer deaths (p = 0.008) were observed among the TCZ-treated patients. The multivariate adjusted Cox regression model showed a significantly higher survival rate among TCZ patients compared to controls (hazard ratio (HR): 0.157, 95% confidence interval (95% CI): 0.026-0.951; p = 0.044). The hazard ratio for mortality in the TCZ group was 0.098 (95% CI: 0.030-0.318; p = 0.0001 using log-rank test). CONCLUSIONS: This study determined that TCZ treatment in COVID-19 patients was associated with better survival, reduced need for mechanical ventilation and reduced hospital-associated mortality.

Evaluation of Using Empiric Glycopeptides in Accordance with the IDSA Guidelines in Hematologic Malignancy Patients with Febrile Neutropenia.

Background: This study aimed to evaluate the effects of the appropriate use of empiric glycopeptide therapy in hematologic malignancy patients with febrile neutropenia (FN). Materials and Methods: Patients with FN who were hospitalized in our clinic and started empiric glycopeptide therapy were retrospectively analyzed. Empiric glycopeptide treatment initial indications were determined according to 7 specific criteria in the IDSA guidelines. In addition, the duration of glycopeptide use according to initial indications, causative pathogens in culture positivity, frequency of VRE infection, and the mortality rate was identified. Results: 87 patients were included. Of these, 102 episodes of FN were analyzed. Appropriate use of glycopeptides was observed in 98% of patients. The most common initial indication for glycopeptide was skin or soft-tissue infection, with 52% (n = 53). The mean duration of glycopeptide use was 11 (2-22) days. The time of glycopeptide use was longer in patients with catheter-related infections than in those with severe mucositis and hemodynamic instability (p = 0,041/p = 0,016). The duration of glycopeptide use was shorter in patients with consolidation therapy than in those without consolidation therapy. The mortality rate in culture-positive patients was significantly higher than in culture-negative patients (p = 0.041). At 72 h, glycopeptide therapy was discontinued in 8 of 79 FN episodes within culture-negative patients. Conclusion: This study showed that the mortality rate was higher in culture-positive patients. Additionally, glycopeptides should be discontinued early with no evidence of gram-positive infection.

Assessment of CD39 expression in regulatory T-cell subsets by disease severity in adult and juvenile COVID-19 cases.

COVID-19 is a disease characterized by acute respiratory failure and is a major health problem worldwide. Here, we aimed to investigate the role of CD39 expression in Treg cell subsets in COVID-19 immunopathogenesis and its relationship to disease severity. One hundred and ninety COVID-19 patients (juveniles, adults) and 43 volunteers as healthy controls were enrolled in our study. Flow cytometric analysis was performed using a 10-color monoclonal antibody panel from peripheral blood samples. In adult patients, CD39+ Tregs increased with disease severity. In contrast, CD39+ Tregs were decreased in juvenile patients in an age-dependent manner. Overall, our study reveals an interesting profile of CD39-expressing Tregs in adult and juvenile cases of COVID-19. Our results provide a better understanding of the possible role of Tregs in the mechanism of immune response in COVID-19 cases.

Healthcare-Associated Stenotrophomonas maltophilia Bacteraemia: Retrospective Evaluation of Treatment and Outcome.

Introduction Stenotrophomonas maltophilia (SM) is one of the common gram-negative pathogens that cause nosocomial infections. The aim of the present study is to evaluate the treatment and outcome of SM bacteraemia. Materials and Methods We retrospectively evaluated antimicrobial treatment in adult patients with nosocomial SM bacteraemia, with the 14th and 30th-day mortality as the outcome. Results In total, 140 adult patients with SM bacteraemia who were diagnosed between January 1, 2002, and December 31, 2016 were enrolled in the present study. Seventy-one (50.7%) patients were in the intensive care unit (ICU). The 14th and the 30th-day mortality rates were 32.9% (n=46) and 45.7% (n=64), respectively. Female sex (OR, 7.47; 95% CI 1.61-34.47, p<0.01), steroid use within the last month (OR, 10.2; 95% CI 1.27-82.27, p=0.029), Pittsburgh bacteraemia score (PBS) ≥4 (OR, 39.9; 95% CI 4.96-321.32, p<0.001) and solid organ malignancy (OR, 9.6; 95% CI 1.73-53.72, p<0.01) were independent risk factors for 14th day mortality. Removal of the catheter was an independent protective factor for both 14th (OR, 0.05; 95% CI 0.22-0.010, p<0.001) and 30th day (OR, 0.039;95% CI 0.164-0.009, p<0.001) mortality. We did not detect any difference between treatment regimens including trimethoprim-sulfamethoxazole (TMP/SMX) or levofloxacin in terms of mortality. We found that TMP/SMX and levofloxacin combination did not significantly improve patient prognosis. Conclusion  Due to the high mortality rates associated with nosocomial SM bacteraemia, adequate antibiotic therapy should be initiated immediately in the suspicion of infection, and prompt removal of any indwelling central venous catheter is important.

Conventional Amphotericin B Associated Nephrotoxicity in Patients With Hematologic Malignancies.

INTRODUCTION:  Amphotericin B (AmB-d) is one of the most effective therapeutic options against frequently life-threatening systemic fungal infections in patients with hematologic malignancies. However, significant adverse effects including nephrotoxicity associated with its use limit its more widespread use. The objectives of our study were to determine the incidence of AmB-d associated nephrotoxicity, to evaluate clinical and epidemiological characteristics of patients, and to support the notion that conventional amphotericin B remains a valid therapeutic option among hematologic patients with proper patient selection. MATERIALS AND METHODS: A total of 110 patients with hematologic malignancies were admitted to our Hematology Unit between January 2014 and November 2017 who required anti-fungal therapy during intensive systemic chemotherapy. The incidence of AmB-d associated nephrotoxicity, side effect profile, time to nephrotoxicity, and clinical and epidemiological characteristics associated with treatment success were assessed retrospectively. RESULTS: Of the 110 patients receiving AmB-d, 70 (63.6%) were male and 40 (36.4%) were female. The mean age of participants was 44 years. The most common diagnosis was acute myeloid leukemia (n=53, 48.2%), and the most common chemotherapy protocol was 7 + 3 remission-induction (cytarabine 100 mg/m² days 1-7, Idarubicin 12 mg/m² days 1-3; n=24, 21.8%). In 56.4% of the patients, antifungal therapy was given empirically. In 40 patients (36.4%), nephrotoxicity was observed following antifungal treatment, and only four patients had stage 3 renal failure. The mean duration of time to nephrotoxicity from initiation of amphotericin B was four days (min: 2, max: 31). All patients were found to receive at least one additional potential nephrotoxic treatment during the antifungal treatment process.  Conclusion: AmB-d is associated with a significant risk of nephrotoxicity. In most hematological patients, antifungal treatment is initiated empirically, and patients received prolonged courses of treatment. Therefore, it is plausible to initiate such treatment with AmB-d, when one considers the already high treatment costs in this patient group as well as the fact that AmB-d offers similar efficacy to antifungal agents at a lower cost. AmB-d may be recommended as a first-line agent in this patient group with the introduction of newer and more costly antifungal agents when needed, on the basis of the fact that these patients can be closely monitored in a hospital setting, reversible nature of nephrotoxicity upon discontinuation, and rare occurrence of severe renal failure requiring dialysis.

Vancomycin-resistant enterococci infection and predisposing factors for infection and mortality in patients with acute leukaemia and febrile neutropenia.

BACKGROUND: Vancomycin-resistant enterococcus (VRE) is an infectious agent that can increase morbidity and mortality, especially in patients with neutropenia in haematology departments. We analysed VRE infections and mortality rates among VRE colonized patients with acute leukaemia, defined predisposing risk factors for infection and mortality, and investigated the influence of daptomycin or linezolid treatment on mortality. PATIENTS-METHODS: We included 200 VRE colonized adult acute leukaemia patients with febrile neutropenia between January 2010 and January 2016. Data were collected from electronic files. RESULTS: There were 179 patients in the colonized group, and 21 patients in the infected group. Enterococcus faecium (van A) was isolated from all patients. The infection rate was 10.5 %, and the types of infections noted were as follows: bloodstream (n = 14; 66.7 %), skin and soft tissue (n = 3; 14.3 %), urinary (n = 2; 9.5 %), and others (9.5 %). In the multivariate logistic regression analysis, exposure to invasive procedures, coinfection status, and >15 days of VRE positivity were independent risk factors for VRE infections. In hospital mortality rates were 57.1 % in the infected group, and 9.5 % in the colonized group (p < 0.001). Older age, female gender, absolute neutropenia, and coinfection status were statistically significant predictor of survival. CONCLUSION: Vancomycin-resistant enterococcus infections are associated with high morbidity and mortality in haematology patients with neutropenia. Clinicians should be aware of predisposing risk factors for VRE infection to avoid unfavourable outcomes. We believe that larger studies are necessary regarding the influence of treatment with daptomycin and linezolid.

The Outcome of Antifungal Prophylaxis with Posaconazole in Patients with Acute Myeloid Leukemia: A Single-Center Study

Objective: Invasive fungal infections (IFIs) are a significant cause of morbidity and mortality among neutropenic patients undergoing chemotherapy for acute myeloid leukemia (AML) and stem cell transplantation. The aim of this study was to evaluate the real-life impact of posaconazole prophylaxis. Materials and Methods: Eighty-four adult patients were included with AML under remission induction chemotherapy and posaconazole prophylaxis. The 34 patients in the control group did not receive primary antifungal prophylaxis. The period between June 2006 and January 2009, when antifungal prophylaxis was not administered (control group), was retrospectively compared to the period between December 2010 and May 2012 when primary oral posaconazole prophylaxis was administered in similar conditions (posaconazole group) according to the use of antifungal agents for treatment, breakthrough infections, galactomannan performance, and the necessity for performing bronchoalveolar lavage (BAL) procedures. Results: The two groups were compared according to the use of antifungal agents; progression to a different antifungal agent was found in 34/34 patients (100%) in the control group and in 9/84 patients (11%) in the posaconazole group (p<0.001). There were four breakthrough IFIs (4/84, 4.8%) in the posaconazole group and 34 IFIs in the control group (p<0.001). In addition, 15/34 patients (44%) in the control group required BAL compared to 11/84 patients (13%) in the posaconazole group (p<0.001). Posaconazole treatment was discontinued within 7-14 days in 7/84 patients (8.3%) due to poor oral compliance related to mucositis after chemotherapy. Conclusion: Posaconazole appears to be effective and well-tolerated protection against IFIs for AML patients.

Comparison of galactomannan, beta-D-glucan, and Aspergillus DNA in sera of high-risk adult patients with hematological malignancies for the diagnosis of invasive aspergillosis.

BACKGROUND/AIM: Invasive aspergillosis (IA) is a fatal infection that is difficult to diagnose in immunocompromised patients. In this study, Aspergillus-specific DNA was searched using real-time PCR (RT-PCR) in serum samples. Galactomannan (GM) and/or beta-D-glucan (BDG) tests were previously performed on these samples for 70 neutropenic patients with hematological malignancy. MATERIALS AND METHODS: The patients were categorized according to the criteria of the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG). Among the patient serum samples, the first positive GM or BDG test sample and the median sample of GM or BDG test for negative patients were used to detect DNA levels by RT-PCR method (Light Cycler 480, Roche Molecular Biochemicals, Meylan, France) using a commercial kit (Way2Gene Fungi; Genmar, Izmir, Turkey). RESULTS: When the proven and probable IA group were considered as real patients, sensitivity of Aspergillus-specific DNA test was 90%, specificity was 73.3%, positive predictive value was 81.8%, and negative predictive value was 84.6%. CONCLUSION: This study found that searching for specific DNA by RT-PCR method has a sensitivity as high as the GM test. Although specificity was rather low, it was concluded that it can be used jointly with GM and BDG tests after decreasing contamination by severe laboratory applications.

Serum galactomannan levels in the diagnosis of invasive aspergillosis.

BACKGROUND/AIMS: In this study, the sensitivity-specificity of galactomannan-enzyme immunoassay (GM-EIA) with a cut-off value of 0.5 for a single, two, or three consecutive positivity in the diagnosis of invasive pulmonary aspergillosis (IPA) in neutropenic patients with hematological malignancy was investigated. METHODS: IPA was classified as "proven," "probable," or "possible" as described in the guidelines prepared by the European Organization for Research and Treatment of Cancer and Mycoses Study Group." Serum samples were collected from the patients twice a week throughout their hospitalization. A total of 1,385 serum samples, with an average of 8.3 samples per episode, were examined. RESULTS: Based on the 165 febrile episodes in 106 patients, 80 (48.5%) were classified as IPA (4 proven, 11 probable, 65 possible) and 85 (51.5%) as non-IPA. The sensitivity/ specificity was 100%/27.1% for a single proven/probable IPA with the cut of value of GM-EIA ≥ 0.5, 86.7%/71.8% for two consecutive positive results, and 73.3%/85.9% for three consecutive positive results. CONCLUSIONS: With the galactomannan levels measured twice a week, consecutive sensitivity decreased and specificity increased. Therefore, an increase may be obtained in sensitivity-specificity by more frequent monitoring of GM-EIA starting from the first day of positivity is detected.

Comparative evaluation of galactomannan optical density indices and culture results in bronchoscopic specimens obtained from neutropenic and non-neutropenic patients.

Aspergillus infections are major causes of morbidity and mortality among immunocompromised patients. This study was designed to investigate the galactomannan assay optical density (OD) indices relative to the culture results in bronchoscopic samples obtained from neutropenic and non-neutropenic patients. Galactomannan OD indices from 1427 samples from 2005 to 2012, which were sent from 839 patients and were composed of bronchial lavage (BL = 727) and bronchoalveolar lavage fluids (BAL = 700), were retrospectively analysed. The recovery rates of Aspergillus species from these specimens were 9.4% from the combined patient group and 13.3% from the neutropenic group. Aspergillus fumigatus complex was the most frequently isolated species. The mean and median OD indices of the positive and negative culture samples are approximately 5 and 1, respectively, and 91% of all culture-positive samples have ≥1 OD index value. The receiver-operating characteristics curve analysis demonstrated that the feasibility of the Aspergillus galactomannan assay and Aspergillus galactomannan test has superior accuracy in BAL compared to BL fluids, and the test is not affected by the immune status of the patient. We suggest that the Aspergillus galactomannan test, which uses bronchoscopic material, leads to an earlier diagnosis and if the OD index is found ≥1, fungal growth can be expected.