Cytomegalovirus Reactivations in Allogeneic Hematopoietic Stem Cell Transplantation from HLA-Matched and Haploidentical Donors with Post-Transplantation Cyclophosphamide.

Cytomegalovirus (CMV) reactivations cause significant morbidity in allogeneic hematopoietic stem cell transplantation (HSCT) recipients. Graft-versus-host disease (GVHD) prophylaxis with post-transplantation cyclophosphamide (PTCy) is associated with an increased risk of CMV infections. Data are limited comparing HSCT with PTCy performed from matched sibling donors (MSDs), matched unrelated donors (MUDs), and haploidentical (Haplo) donors. In the present study, we aimed to characterize CMV reactivation and recurrence in patients with hematologic malignancies undergoing HSCT from MSD, MUD, and Haplo donors using PTCy as GVHD prophylaxis in the pre-letermovir era. We also analyzed risk factors of CMV reactivation, including GVHD as a time-dependent variable, on the incidence and mortality associated with CMV infections. We analyzed CMV reactivation in patients undergoing HSCT from 160 MSDs, 124 MUDs, and 82 Haplo donors from a single institution. Uniform GVHD prophylaxis with PTCy, sirolimus, and mycophenolate mofetil was given irrespective of donor type. Overall, 46% of patients had at least 1 CMV reactivation. The 1-year cumulative incidence of CMV infection was 39% for MSD, 44% for MUD, and 62% for Haplo donors (P < .001), with 96% of reactivations occurring before day +100. Multivariate analysis identified factors associated with the first CMV reactivation, including Haplo donor, positive recipient CMV serology, older patient age, and grade II-IV acute GVHD. The 1-year cumulative incidence of second reactivation from HSCT was 13%. Recipient CMV seropositivity, older patient age, and grade II-IV acute GVHD, but not type of donor, were identified as adverse factors for second CMV reactivation in multivariate analysis. The 1-year cumulative incidence of a third reactivation post HSCT was 4.4%. Ten cases of CMV disease were recorded, with no attributable deaths. Nevertheless, the risk for nonrelapse mortality was greater for patients who experienced CMV reactivation in multivariate time-dependent Cox model analysis. CMV reactivation is frequent in HSCT with PTCy in patients not receiving letermovir prophylaxis. Identified risk factors include the use of a Haplo donor, recipient CMV seropositivity, and grade II-IV acute GVHD. The prevalence of recurrent CMV reactivations is a noteworthy issue, especially after acute GVHD, warranting trials of secondary prophylaxis strategies.

Expert Consensus: Main Risk Factors for Poor Prognosis in COVID-19 and the Implications for Targeted Measures against SARS-CoV-2.

The clinical evolution of patients infected with the Severe Acute Respiratory Coronavirus type 2 (SARS-CoV-2) depends on the complex interplay between viral and host factors. The evolution to less aggressive but better-transmitted viral variants, and the presence of immune memory responses in a growing number of vaccinated and/or virus-exposed individuals, has caused the pandemic to slowly wane in virulence. However, there are still patients with risk factors or comorbidities that put them at risk of poor outcomes in the event of having the coronavirus infectious disease 2019 (COVID-19). Among the different treatment options for patients with COVID-19, virus-targeted measures include antiviral drugs or monoclonal antibodies that may be provided in the early days of infection. The present expert consensus is based on a review of all the literature published between 1 July 2021 and 15 February 2022 that was carried out to establish the characteristics of patients, in terms of presence of risk factors or comorbidities, that may make them candidates for receiving any of the virus-targeted measures available in order to prevent a fatal outcome, such as severe disease or death. A total of 119 studies were included from the review of the literature and 159 were from the additional independent review carried out by the panelists a posteriori. Conditions found related to strong recommendation of the use of virus-targeted measures in the first days of COVID-19 were age above 80 years, or above 65 years with another risk factor; antineoplastic chemotherapy or active malignancy; HIV infection with CD4+ cell counts < 200/mm3; and treatment with anti-CD20 immunosuppressive drugs. There is also a strong recommendation against using the studied interventions in HIV-infected patients with a CD4+ nadir <200/mm3 or treatment with other immunosuppressants. Indications of therapies against SARS-CoV-2, regardless of vaccination status or history of infection, may still exist for some populations, even after COVID-19 has been declared to no longer be a global health emergency by the WHO.

Response to Vaccines in Patients with Immune-Mediated Inflammatory Diseases: A Narrative Review.

Patients with immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis and inflammatory bowel disease, are at increased risk of infection. International guidelines recommend vaccination to limit this risk of infection, although live attenuated vaccines are contraindicated once immunosuppressive therapy has begun. Biologic therapies used to treat IMIDs target the immune system to stop chronic pathogenic process but may also attenuate the protective immune response to vaccines. Here, we review the current knowledge regarding vaccine responses in IMID patients receiving treatment with biologic therapies, with a focus on the interleukin (IL)-12/23 inhibitors. B cell-depleting therapies, such as rituximab, strongly impair vaccines immunogenicity, and tumor necrosis factor (TNF) inhibitors and the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) fusion protein abatacept are also associated with attenuated antibody responses, which are further diminished in patients taking concomitant immunosuppressants. On the other hand, integrin, IL-6, IL-12/23, IL-17, and B-cell activating factor (BAFF) inhibitors do not appear to affect the immune response to several vaccines evaluated. Importantly, treatment with biologic therapies in IMID patients is not associated with an increased risk of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or developing severe disease. However, the efficacy of SARS-CoV-2 vaccines on IMID patients may be reduced compared with healthy individuals. The impact of biologic therapies on the response to SARS-CoV-2 vaccines seems to replicate what has been described for other vaccines. SARS-CoV-2 vaccination appears to be safe and well tolerated in IMID patients. Attenuated but, in general, still protective responses to SARS-CoV-2 vaccination in the context of certain therapies warrant current recommendations for a third primary dose in IMID patients treated with immunosuppressive drugs.

Common seasonal respiratory virus infections in allogeneic stem cell transplant recipients during the SARS-COV-2 pandemic.

The SARS-COV-2 pandemic has led to strict and generalized transmission prevention measures that may have changed the epidemiological landscape of common seasonal respiratory virus (CSRV). Through a prospective CSRV survey program conducted from 2016 onwards in allogeneic stem cell transplant (allo-HSCT) recipients with respiratory symptoms, we aimed to analyze and compare the epidemiology and characteristics of CSRV over three consecutive periods [from February 1 to September 30 of 2018 (P1), 2019 (P2), and 2020 (P3)]. CSRV screening was performed through multiplex PCR assays during the study period. We identified 188 consecutive allo-HSCT recipients with 406 episodes screened for CSRV during the study period, of which 147 developed 300 CSRV. In P1 and P2 we diagnosed 115 (38.3%) and 145 (48.3%) CSRV episodes, respectively, whereas in P3 only 40 (13.3%) episodes were detected (p < 0.001). During P3, we observed a reduction of 80.2% in Ev/Rh, 93.3% in RSV, 80% in hIV, 96.3% HPIV, 68.4% in hMPV, 77.7% in ADV, 100% in HBoV, and 53.6% in HCoV as compared to P1 and P2. Consequently, we also observed a decline in absolute numbers of lower respiratory tract disease (68.1%), co-infections (91.7%), and hospitalizations (72.6%) during P3. We diagnosed SARS-COV-2 in nine allo-HSCT recipients, representing 23% of all CSRV detections in that period. In conclusion, we provide evidence of a significant drop in CSRV circulation during the SARS-COV-2 pandemic in our allo-HSCT recipients, indicating that prevention measures in the general population are highly effective in reducing CSRV prevalence and its complications in immunocompromised patients.

Recommendations for screening, monitoring, prevention, and prophylaxis of infections in adult and pediatric patients receiving CAR T-cell therapy: a position paper.

Chimeric antigen receptor (CAR) T-cell therapy is one of the most promising emerging treatments for B-cell malignancies. Recently, two CAR T-cell products (axicabtagene ciloleucel and tisagenlecleucel) have been approved for patients with aggressive B-cell lymphoma and acute lymphoblastic leukemia; many other CAR-T constructs are in research for both hematological and non-hematological diseases. Most of the patients receiving CAR-T therapy will develop fever at some point after infusion, mainly due to cytokine release syndrome (CRS). The onset of CRS is often indistinguishable from an infection, which makes management of these patients challenging. In addition to the lymphodepleting chemotherapy and CAR T cells, the treatment of complications with corticosteroids and/or tocilizumab increases the risk of infection in these patients. Data regarding incidence, risk factors and prevention of infections in patients receiving CAR-T cell therapy are scarce. To assist in patient care, a multidisciplinary team from hospitals designated by the Spanish Ministry of Health to perform CAR-T therapy prepared these recommendations. We reviewed the literature on the incidence, risk factors, and management of infections in adult and pediatric patients receiving CAR-T cell treatment. Recommendations cover different areas: monitoring and treatment of hypogammaglobulinemia, prevention, prophylaxis, and management of bacterial, viral, and fungal infections as well as vaccination prior and after CAR-T cell therapy.

Fungal co-infection in COVID-19 patients: Should we be concerned?

Critically ill COVID-19 patients have higher pro-inflammatory (IL-1, IL-2, IL-6, tumor necrosis alpha) and anti-inflammatory (IL-4, IL-10) cytokine levels, less CD4 interferon-gamma expression, and fewer CD4 and CD8 cells. This severe clinical situation increases the risk of serious fungal infections, such as invasive pulmonary aspergillosis, invasive candidiasis or Pneumocystis jirovecii pneumonia. However, few studies have investigated fungal coinfections in this population. We describe an update on published reports on fungal coinfections and our personal experience in three Spanish hospitals. We can conclude that despite the serious disease caused by SARS-CoV-2 in many patients, the scarcity of invasive mycoses is probably due to the few bronchoscopies and necropsies performed in these patients because of the high risk in aerosol generation. However, the presence of fungal markers in clinically relevant specimens, with the exception of bronchopulmonary colonization by Candida, should make it advisable to early implement antifungal therapy.

Community acquired respiratory virus infections in adult patients undergoing umbilical cord blood transplantation.

Characteristics and risk factors (RFs) of community-acquired respiratory virus (CARV) infections after umbilical cord blood transplantation (UCBT) are lacking. We retrospectively analyzed CARV infections in 216 single-unit myeloablative UCBT recipients. One-hundred and fourteen episodes of CARV infections were diagnosed in 62 (29%) patients. Upper respiratory tract disease (URTD) occurred in 61 (54%) whereas lower respiratory tract disease (LRTD) in 53 (46%). The 5-year cumulative incidence of CARV infection was 29%. RFs for developing CARV infections were: prednisone-based graft-versus-host disease (GVHD) prophylaxis and grade II-IV acute GVHD. RFs analysis of CARV progression to LRTD identified 2007-2009 period and absolute lymphocyte count (ALC) < 0.5 × 109/L. ALC < 0.5 × 109/L had a negative impact on day 60 mortality in both overall CARV and those with LRTD, whereas proven LRTD was associated with higher day 60 mortality. CARV infections had a negative effect on non-relapse mortality. Overall survival at day 60 after CARV detection was significantly lower in recipients with LRTD compared with URTD (74% vs. 93%, respectively). In conclusion, CARV infections after UCBT are frequent and may have a negative effect in the outcomes, in particular in the context of lymphocytopenia.

The clinical benefit of instituting a prospective clinical community-acquired respiratory virus surveillance program in allogeneic hematopoietic stem cell transplantation.

BACKGROUND: There is a lack of studies comparing clinical outcomes among retrospective versus prospective cohorts of allogeneic stem cell transplant (allo-HCT) recipients with community acquired respiratory virus (CARV) infections. METHODS: We compare outcomes in two consecutive cohorts of allo-HCT recipients with CARV infections. The retrospective cohort included 63 allo-HCT recipients with 108 CARV infections from January 2013 to April 2016 who were screened and managed following standard clinical practice based on influenza and respiratory syncytial virus rapid antigen detection methods. The prospective cohort was comprised of 144 consecutive recipients with 297 CARV episodes included in a prospective interventional clinical surveillance program (ProClinCarvSur-P) based on syndromic multiplex PCR as first-line test from May 2016 to December 2018 at a single transplant center. RESULTS: CARV infections in the retrospective cohort showed more severe clinical features at the time of diagnosis compared to the prospective cohort (fever 83% vs. 57%, hospital admission 69% vs. 28% and lower respiratory tract 58% vs. 31%, respectively, p ≤ 0.002 for all comparisons). Antiviral therapy was more commonly prescribed in the prospective cohort (69 vs. 43 treated CARV episodes), particularly at the upper respiratory tract disease stage (34 vs. 12 treated CARV episodes). Three-month all-cause mortality was significantly higher in the retrospective cohort (n = 23, 37% vs. n = 10, 7%, p < 0.0001). Multivariate logistic regression analysis showed that recipients included in ProClinCarvSur-P had lower mortality rate [odds ratio 0.31, 95% confidence interval 0.12-0.7, p = 0.01]. CONCLUSION: This study report on outcome differences when reporting retrospective vs. prospective CARV infections after allo-HCT. Recipients included in a ProClinCarvSur-P had lower mortality.

The effect of timing on community acquired respiratory virus infection mortality during the first year after allogeneic hematopoietic stem cell transplantation: a prospective epidemiological survey.

The effect of timing of community acquired respiratory virus (CARV) infection after allogeneic hematopoietic stem cell transplant (allo-HCT) is an as yet unsettled issue. We evaluate this issue by including all consecutive allo-HCT recipients with molecularly-documented CARV infection during the first year after transplant. The study cohort was drawn from a prospective longitudinal survey of CARV in allo-HCT recipient having respiratory symptoms conducted from December 2013 to December 2018 at two Spanish transplant centers. Respiratory viruses in upper and/or lower respiratory specimens were tested using multiplex PCR panel assays. The study cohort comprised 233 allo-HCT recipients with 376 CARV infection episodes diagnosed during the first year after allo-HCT. Overall, 60% of CARV episodes occurred within the first 6 months (227 out of 376). Thirty patients (13%) had died at 3 months after CARV detection, of which 25 (83%) were recipients developing CARV within the first 6 months after transplant. Multivariate analysis identified four risk factors for mortality: ATG used as part of conditioning regimen [odds ratio (OR) 2.8, 95% confidence interval (C.I.) 1.21-6.4, p = 0.01], CARV lower respiratory tract disease (OR 3.4, 95% C.I. 1.4-8.4, p = 0.007), CARV infection within the first 6 months of transplant (OR 3.04, 95% C.I. 1.1-8.7, p = 0.03), and absolute lymphocyte count <0.2 × 109/L (OR 2.4, 95% C.I. 1-5.3, p = 0.04). Developing CARV infection within the first 6 months was associated with higher mortality. Our data supports that the timing of CARV development after allo-HCT could be of major interest.

Fungal infections following treatment with monoclonal antibodies and other immunomodulatory therapies.

Tumor necrosis factor (TNF) is a proinflammatory cytokine involved in a wide range of important physiologic processes and has a pathologic role in some diseases. TNF antagonists (infliximab, adalimumab, etanercept) are effective in treating inflammatory conditions. Antilymphocyte biological agents (rituximab, alemtuzumab), integrin antagonists (natalizumab, etrolizumab and vedolizumab), interleukin (IL)-17A blockers (secukinumab, ixekizumab) and IL-2 antagonists (daclizumab, basiliximab) are widely used after transplantation and for gastroenterological, rheumatological, dermatological, neurological and hematological disorders. Given the putative role of these host defense elements against bacterial, viral and fungal agents, the risk of infection during a treatment with these antagonists is a concern. Fungal infections, both opportunistic and endemic, have been associated with these biological therapies, but the causative relationship is unclear, especially among patients with poor control of their underlying disease or who are undergoing steroid therapy. Potential recipients of these drugs should be screened for latent endemic fungal infections. Cotrimoxazole prophylaxis could be useful for preventing Pneumocystis jirovecii infection in patients over 65 years of age who are taking TNF antagonists, antilymphocyte biological agents or who have lymphopenia and are undergoing concomitant steroid therapy. As with other immunosuppressant drugs, TNF antagonists and antilymphocyte antibodies should be discontinued for patients with active infectious disease.

High Heterogeneity of Multidrug-Resistant Enterobacteriaceae Fecal Levels in Hospitalized Patients Is Partially Driven by Intravenous ß-Lactams.

Multidrug-resistant Enterobacteriaceae (MRE) colonize the intestine asymptomatically from where they can breach into the bloodstream and cause life-threatening infections, especially in heavily colonized patients. Despite the clinical relevance of MRE colonization levels, we know little about how they vary in hospitalized patients and the clinical factors that determine those levels. Here, we conducted one of the largest studies of MRE fecal levels by tracking longitudinally 133 acute leukemia patients and monitoring their MRE levels over time through extensive culturing. MRE were defined as Enterobacteriaceae species that acquired nonsusceptibility to ≥1 agent in ≥3 antimicrobial categories. In addition, due to the selective media used, the MRE had to be resistant to third-generation cephalosporins. MRE were detected in 60% of the patients, but their fecal levels varied considerably among patients and within the same patient (>6 and 4 orders of magnitude, respectively). Multivariate analysis of clinical metadata revealed an impact of intravenous beta-lactams (i.e., meropenem and piperacillin-tazobactam), which significantly diminished the fecal MRE levels in hospitalized patients. Consistent with a direct action of beta-lactams, we found an effect only when the patient was colonized with strains sensitive to the administered beta-lactam (P < 0.001) but not with nonsusceptible strains. We report previously unobserved inter- and intraindividual heterogeneity in MRE fecal levels, suggesting that quantitative surveillance is more informative than qualitative surveillance of hospitalized patients. In addition, our study highlights the relevance of incorporating antibiotic treatment and susceptibility data of gut-colonizing pathogens for future clinical studies and in clinical decision-making.

Genomic characterization of Citrobacter freundii strains coproducing OXA-48 and VIM-1 carbapenemase enzymes isolated in leukemic patient in Spain.

Background: The emergence of carbapenemase-producing (CP) Citrobacter freundii poses a significant threat to public health, especially in high-risk populations. In this study, whole genome sequencing was used to characterize the carbapenem resistance mechanism of three C. freundii clinical isolates recovered from fecal samples of patients with acute leukemia (AL) from Spain. Materials and methods: Twelve fecal samples, collected between 2013 and 2015 from 9 patients with AL, were screened for the presence of CP strains by selecting them on MacConkey agar supplemented with ertapenem (0.5 mg/L). Bacteria were identified by MALDI-TOF mass spectrometry and were phenotypically characterized. Whole genome sequencing of C. freundii isolates was performed using the MinION and MiSeq Illumina sequencers. Bioinformatic analysis was performed in order to identify the molecular support of carbapenem resistance and to study the genetic environment of carbapenem resistance encoding genes. Results: Three carbapenem-resistant C. freundii strains (imipenem MIC≥32 mg/L) corresponding to three different AL patients were isolated. Positive modified Carba NP test results suggested carbapenemase production. The genomes of each C. freundii tested were assembled into a single chromosomal contig and plasmids contig. In all the strains, the carbapenem resistance was due to the coproduction of OXA-48 and VIM-1 enzymes encoded by genes located on chromosome and on an IncHI2 plasmid, respectively. According to the MLST and the SNPs analysis, all strains belonged to the same clone ST169. Conclusion: We report in our study, the intestinal carrying of C. freundii clone ST169 coproducing OXA-48 and VIM-1 identified in leukemic patients.

Incidence, risk factors, and outcome of pulmonary invasive fungal disease after respiratory virus infection in allogeneic hematopoietic stem cell transplantation recipients.

BACKGROUND: There is growing evidence that community-acquired respiratory virus (CARV) increases the risk of pulmonary invasive fungal disease (IFD) in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) setting. To date, there is a lack of knowledge regarding the risk factors (RFs), as well as the most critical period for subsequent onset of IFD after CARV infections in allo-HSCT recipients. METHODS: In this prospective longitudinal observational CARV survey, we analyzed the effect of CARV on subsequent IFD development in 287 adult allo-HSCT recipients diagnosed with 597 CARV episodes from December 2013 to December 2018. Multiplex PCR panel assays were used to test CARVs in respiratory specimens. FINDINGS: Twenty-nine out of 287 allo-HSCT recipients (10%) developed IFD after a CARV episode. The median time of IFD onset was 21 days (range, 0-158 days) from day of the first CARV detection. Generalized estimating equation model identified 4 risk factors for IFD: ATG-based conditioning regimen [odds ratio (OR) 2.34, 95% confidence interval (CI) 1.05-5.2, P = .038], CARV lower respiratory tract disease (OR 10.6, 95% CI 3.7-30.8, P < .0001), CARV infection during the first year after transplant (OR 5.34, 95% CI 1.3-21.8, P = .014), and corticosteroids during CARV (OR 2.6, 95% CI 1.1-6.3, P = .03). CONCLUSION: Allo-HSCT recipients conditioned with ATG and under corticosteroid therapy at the time of CARV LRTD during the first year after transplant may require close monitoring for subsequent IFD.

Incidence and outcome of invasive fungal disease after front-line intensive chemotherapy in patients with acute myeloid leukemia: impact of antifungal prophylaxis.

Few reports analyze the incidence and clinical outcome of invasive fungal disease (IFD) in patients with newly diagnosed acute myeloid leukemia (AML) undergoing intensive chemotherapy, and thus the impact of different antifungal prophylactic regimens remains unclear. We analyze the incidence and clinical outcome of IFD in a large series of adult AML patients undergoing front-line intensive induction and consolidation chemotherapy between 2004 and 2015 in a single institution. Three antifungal prophylaxis regimens were given (2004-2005 oral fluconazole, 2006-2012 intravenous itraconazole, and 2013-2015 voriconazole). Overall, 285 patients and 589 intensive chemotherapy episodes were assessed (47%) (induction courses 47% and consolidation 53%). The median age was 51 years (range, 17-65). We observed 56 (10%) episodes of IFD. According to the EORTC 2008 criteria, IFD was classified as possible (29, 52%), probable (17, 30%), and proven (10, 18%). Possible/probable/proven IFD rate was significantly lower during HiDAC consolidation as compared to any anthracycline-containing chemotherapy courses (2% vs. 11%, P = 0.001), and under voriconazole prophylaxis as compared to itraconazole and fluconazole (6% vs. 11% vs. 15%, P = 0.007), and the multivariate analysis showed that they were independent risk factors. Patients under voriconazole prophylaxis had shorter hospitalization duration and less frequent use of empirical or directed antifungal therapy. In conclusion, IFD was a frequent complication during upfront intensive chemotherapy courses for adult AML patients. This retrospective study shows that voriconazole prophylaxis was feasible and associated with a lower risk of IFD compared with intravenous itraconazole or oral fluconazole schedules.

High delayed mortality after the first episode of Clostridium difficile infection.

Clostridium difficile infection (CDI) is characterized by a high delayed and unrelated mortality. Predicting delayed mortality in CDI patients could allow the implementation of interventions that could reduce these events. A prospective multicentric study was carried out to investigate prognostic factors associated with mortality. It was based on a cohort (July 2015 to February 2016) of 295 patients presenting with CDI. Logistic regression was used and the model was calibrated using the Hosmer-Lemeshow test. The mortality rate at 75 days in our series was 18%. Age (>65 years), comorbidity (defined by heart failure, diabetes mellitus with any organ lesion, renal failure, active neoplasia or immunosuppression) and fecal incontinence at clinical presentation were associated with delayed (75-day) mortality. When present, each of the aforementioned variables added one point to the score. Mortalities with 0, 1, 2 and 3 points were 0%, 9.4%, 18.5% and 38.2%, respectively. The area under the ROC curve was 0.743, and the Hosmer-Lemeshow goodness-of-fit test p value was 0.875. Therefore, the prediction of high delayed mortality in CDI patients by our scoring system could promote measures for increasing survival in suitable cases.

Detection of plasmid-mediated colistin resistance, mcr-1 gene, in Escherichia coli isolated from high-risk patients with acute leukemia in Spain.

BACKGROUND: Bacterial infections in immunocompromised patients are associated with a high mortality and morbidity rate. In this high-risk group, the presence of multidrug-resistant (MDR) bacteria, particularly bacteria that harbor a transferable antibiotic resistance gene, complicates the management of bacterial infections. In this study, we investigated the presence of the transferable colistin resistance mcr genes in patients with leukemia in Spain. METHODS: 217 fecal samples collected in 2013-2015 from 56 patients with acute leukemia and colonized with MDR Enterobacteriaceae strains, were screened on September 2017 for the presence of the colistin resistance mcr genes (mcr-1 to -5) by multiplex PCR. mcr positive strains selected on LBJMR and MacConkey supplemented with colistin (2 µg/ml) media were phenotypically and molecularly characterized by antimicrobial susceptibility testing, minimum inhibitory concentration, multilocus sequence typing and plasmid characterization. RESULTS: Among 217 fecal samples, 5 samples collected from 3 patients were positive for the presence of the mcr-1 colistin-resistance gene. Four Escherichia coli strains were isolated and exhibited resistance to colistin with MIC = 4 µg/ml. Other genes conferring the resistance to ß-lactam antibiotics have also been identified in mcr-1 positive strains, including blaTEM-206 and blaTEM-98. Three different sequence types were identified, including ST1196, ST140 and ST10. Plasmid characterization allowed us to detect the mcr-1 colistin resistance gene on conjugative IncP plasmid type. CONCLUSION: To the best of our knowledge, we have identified the mcr-1 gene for the first time in leukemia patients in Spain. In light of these results, strict measures have been implemented to prevent its dissemination.

Extended-pulsed fidaxomicin versus vancomycin in patients 60 years and older with Clostridium difficile infection: cost-effectiveness analysis in Spain.

The cost of treating Clostridium difficile infection (CDI) in Spain is substantial. Findings from the randomised, controlled, open-label, phase 3b/4 EXTEND study showed that an extended-pulsed fidaxomicin (EPFX) regimen was associated with improved sustained clinical cure and reduced recurrence of CDI versus vancomycin in patients aged 60 years and older. We assessed the cost-effectiveness of EPFX versus vancomycin for the treatment of CDI in patients aged 60 years and older from the perspective of the National Health System (NHS) in Spain. We used a Markov model with six health states and 1-year time horizon. Health resources, their unit costs and utilities were based on published sources. Key efficacy data and transition probabilities were obtained from the EXTEND study and published sources. A panel of Spanish clinical experts validated all model assumptions. In the analysis, 0.638 and 0.594 quality-adjusted life years (QALYs) per patient were obtained with EPFX and vancomycin, respectively, with a gain of 0.044 QALYs with EPFX. The cost per patient treated with EPFX and vancomycin was estimated to be €10,046 and €10,693, respectively, with a saving of €647 per patient treated with EPFX. For willingness-to-pay thresholds of €20,000, €25,000 and €30,000 per QALY gained, the probability that EPFX was the most cost-effective treatment was 99.3%, 99.5% and 99.9%, respectively. According to our economic model and the assumptions based on the Spanish NHS, EPFX is cost-effective compared with vancomycin for the first-line treatment of CDI in patients aged 60 years and older.

Pulmonary cytomegalovirus (CMV) DNA shedding in allogeneic hematopoietic stem cell transplant recipients: Implications for the diagnosis of CMV pneumonia.

OBJECTIVES: To date no definitive cut-off value for cytomegalovirus (CMV) DNA load in bronchoalveolar lavage (BAL) fluid specimens has been established to discriminate between CMV pneumonia and pulmonary CMV DNA shedding in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients. METHODS: The current retrospective study is aimed at assessing the range of CMV DNA loads quantified in BAL fluid specimens from allo-HSCT patients with pneumonia in which different microorganisms were causally involved. RESULTS: A total of 144 BAL specimens from 123 patients were included. CMV DNA was detected in 56 out of 144 BAL fluid specimens and the median CMV DNA load from patients in whom CMV pneumonia was unlikely or could be tentatively ruled out was 1210 (31-68, 920) IU/ml. The frequency of CMV DNA detection and median CMV DNA loads were comparable, irrespective of the attributable cause of pneumonia. Detection of CMV DNA loads in BAL fluid specimens >500 IU/ml was independently associated with pneumonia-attributable mortality. CONCLUSIONS: The current study highlights the difficulty in establishing universal CMV DNA load thresholds in BAL fluid specimens for distinguishing between CMV pneumonia and pulmonary CMV DNA shedding, and suggests that the presence of CMV DNA in BAL fluid specimens beyond a certain level may have a deleterious impact on patient outcome.

Challenges in Clinical Metaproteomics Highlighted by the Analysis of Acute Leukemia Patients with Gut Colonization by Multidrug-Resistant Enterobacteriaceae.

The microbiome has a strong impact on human health and disease and is, therefore, increasingly studied in a clinical context. Metaproteomics is also attracting considerable attention, and such data can be efficiently generated today owing to improvements in mass spectrometry-based proteomics. As we will discuss in this study, there are still major challenges notably in data analysis that need to be overcome. Here, we analyzed 212 fecal samples from 56 hospitalized acute leukemia patients with multidrug-resistant Enterobactericeae (MRE) gut colonization using metagenomics and metaproteomics. This is one of the largest clinical metaproteomic studies to date, and the first metaproteomic study addressing the gut microbiome in MRE colonized acute leukemia patients. Based on this substantial data set, we discuss major current limitations in clinical metaproteomic data analysis to provide guidance to researchers in the field. Notably, the results show that public metagenome databases are incomplete and that sample-specific metagenomes improve results. Furthermore, biological variation is tremendous which challenges clinical study designs and argues that longitudinal measurements of individual patients are a valuable future addition to the analysis of patient cohorts.