QuantiFERON-CMV assay by chemiluminescence immunoassay: Is it more suitable for real-live monitoring of transplant patients?

BACKGROUND

The QuantiFERONCMV (QF-CMV) assay is an interferon-gamma release assay (IGRA) used to monitor CMV-specific cell-mediated immunity (CMV-CMI) by ELISA in transplant patients. However, a chemiluminescent immunoassay (CLIA) has been developed to quantify IFNG in the QuantiFERON-Tuberculosis (TB) to detect latent TB infection.

OBJECTIVES

The aim of this work is to compare the results of QF-CMV by ELISA with those obtained by CLIA in an automated Liaison XL analyzer using the QuantiFERON-TB Gold Plus reagents.

STUDY DESIGN

The QF-CMV assay had been performed by ELISA in kidney and lung transplant patients between July 2019-April 2023 at the IMIBIC/Reina Sofía Hospital (Cordoba, Spain). The remaining QF-CMV supernatants had been preserved at -80 ºC from then. Now, the IFNG levels in the same samples were determined by CLIA.

RESULTS

One hundred and three QF-CMV supernatants from kidney (n = 50) and lung (n = 53) transplant patients were selected. An agreement of 87.4 % (kappa coefficient 0.788) between CLIA and ELISA was observed. Thirteen (12.6 %) discrepant results were detected. Some Indeterminate results by ELISA converted to Non-reactive by CLIA (0.53-0.92 IU/mL for Mitogen-Nil values). Likewise, borderline Non-reactive results by ELISA were above the 0.2 IU/mL cut-off by CLIA and then were Reactive (0.21-0.31 for CMV-Nil values).

CONCLUSION

CLIA shows substantial concordance with ELISA and acceptable discrepancies. The possible higher sensitivity of CLIA returns a higher number of Reactive results, which entails potential clinical consequences. Therefore, a new threshold to confer protection against CMV infection after transplantation needs to be defined.

Real-life experience in two cases of secondary prophylaxis with letermovir for CMV infection in solid organ transplantation

IMPORTANCE

This observation provides comprehensive data on the clinical correlates of both cytomegalovirus (CMV) genotypic follow-up and clinical monitoring and outcomes for two different solid organ transplantation recipients that received letermovir as secondary prophylaxis. Our study emphasizes that monitoring of CMV disease in the patient and early genotypic detection of resistance mutations are essential when using new antiviral drugs for off-label indication in patients experiencing CMV relapses or not responding to standard antiviral therapy. These cases and the bibliography reviewed can be helpful for other researchers and clinicians working in the field to optimize the use of new treatments for transplant recipients since drug-resistant CMV infection is an important emerging problem even with new developments in antiviral treatment.

Phenotypic and Molecular Characterization of an Enterobacter ludwigii Clinical Isolate Carrying a Plasmid-Mediated blaIMI-6 Gene

We report a plasmid-encoded IMI-6 carbapenemase in a clinical isolate of Enterobacter ludwigii from Spain. The isolate belongs to ST641 and was susceptible to expanded-spectrum cephalosporins and resistant to carbapenems. The modified carbapenem inactivation method (mCIM) test was positive, but β-Carba was negative. Whole-genome sequencing identified the blaIMI-6 gene located in a conjugative IncFIIY plasmid and associated with the LysR-like regulator imiR. Both genes were bracketed by an ISEclI-like insertion sequence and a putatively defective ISEc36 insertion sequence. IMPORTANCE IMI carbapenemases confer an unusual resistance pattern of susceptibility to broad-spectrum cephalosporins and piperacillin-tazobactam but decreased susceptibility to carbapenems, which may make them difficult to detect in routine practice. Commercially available molecular methods for the detection of carbapenemases in clinical laboratories do not usually include blaIMI genes, which could contribute to the hidden dissemination of bacteria producing these enzymes. Techniques should be implemented to detect minor carbapenemases that are not very frequent in our environment and control their dissemination.

Memory SARS-CoV-2 T-cell response in convalescent COVID-19 patients with undetectable specific IgG antibodies: a comparative study

Background

During the COVID-19 pandemic, a variable percentage of patients with SARS-CoV-2 infection failed to elicit humoral response. This study investigates whether patients with undetectable SARS-CoV-2 IgG are able to generate SARS-CoV-2 memory T cells with proliferative capacity upon stimulation.

Methods

This cross-sectional study was conducted with convalescent COVID-19 patients, diagnosed with a positive real-time PCR (RT-PCR) from nasal and pharyngeal swab specimens. COVID-19 patients were enrolled ≥3 months after the last PCR positive. Proliferative T-cell response after whole blood stimulation was assessed using the FASCIA assay.

Results

A total of 119 participants (86 PCR-confirmed COVID-19 patients and 33 healthy controls) were randomly filtered from an initial cohort. Of these 86 patients, 59 had detectable (seropositive) and 27 had undetectable (seronegative) SARS-CoV-2 IgG. Seropositive patients were subclassified as asymptomatic/mild or severe according to the oxygen supplementation requirement. SARS-CoV-2 CD3+ and CD4+ T cells showed significantly lower proliferative response in seronegative than in seropositive patients. The ROC curve analysis indicated that ≥ 5 CD4+ blasts/μL of blood defined a "positive SARS-CoV-2 T cell response". According to this cut-off, 93.2% of seropositive patients had a positive T-cell response compared to 50% of seronegative patients and 20% of negative controls (chi-square; p < 0.001).

Conclusions

This proliferative assay is useful not only to discriminate convalescent patients from negative controls, but also to distinguish seropositive patients from those with undetectable SARS-CoV-2 IgG antibodies. Memory T cells in seronegative patients are able to respond to SARSCoV-2 peptides, although at a lower magnitude than seropositive patients.

Efficacy of ceftazidime-avibactam in solid organ transplant recipients with bloodstream infections caused by carbapenemase-producing Klebsiella pneumoniae

We aimed to compare the efficacy of ceftazidime-avibactam (CAZ-AVI) versus the best available therapy (BAT) in solid organ transplant (SOT) recipients with bloodstream infection caused by carbapenemase-producing Klebsiella pneumoniae (CPKP-BSI). A retrospective (2016-2021) observational cohort study was performed in 14 INCREMENT-SOT centers (ClinicalTrials.gov identifier: NCT02852902). Outcomes were 14-day and 30-day clinical success (complete resolution of attributable manifestations, adequate source control and negative follow-up blood cultures) and 30-day all-cause mortality. Multivariable logistic and Cox regression analyses adjusted for the propensity score to receive CAZ-AVI were constructed. Among 210 SOT recipients with CPKP-BSI, 149 received active primary therapy with CAZ-AVI (66/149) or BAT (83/149). Patients treated with CAZ-AVI had higher 14-day (80.7% versus 60.6%, P=0.011) and 30-day (83.1% versus 60.6%, P=0.004) clinical success and lower 30-day mortality (13.25% versus 27.3%, P=0.053) than those receiving BAT. In the adjusted analysis, CAZ-AVI increased the probability of 14-day (adjusted odds ratio [aOR]: 2.65; 95% confidence interval [95%CI]: 1.03-6.84, P=0.044) and 30-day clinical success (aOR: 3.14; 95%CI: 1.17-8.40; P=0.023). In contrast, CAZ-AVI therapy was not independently associated with 30-day mortality. In the CAZ-AVI group, combination therapy was not associated with better outcomes. In conclusion, CAZ-AVI may be considered a first-line treatment in SOT recipients with CPKP-BSI. SUMMARY SENTENCE: We retrospectively analyzed a cohort of 210 SOT recipients with bloodstream infection due to carbapenemase-producing Klebsiella pneumoniae. Among 149 patients receiving active therapy, 83 were treated with CAZ-AVI and 66 with other regimens. CAZ-AVI was an independent predictor of 14-day and 30-day clinical success.

Role of IP-10 to predict clinical progression and response to IL-6 blockade with Sarilumab in early COVID-19 pneumonia. A subanalysis of the SARICOR clinical trial

Background

Clinical Trial of Sarilumab in Adults With COVID-19 (SARICOR) showed that patients with COVID-19 pneumonia and increased levels of interleukin (IL)-6 might benefit from blockade of IL6-pathway. However, the benefit from this intervention might not be uniform. In this subanalysis, we sought to determine if other immunoactivation markers, besides IL-6, could identify which subgroup of patients benefit the most of this intervention.

Methodology

The SARICOR trial was a phase II, open-label, multicentre, controlled (July 2020-March 2021) in which patients were randomized to receive usual care (UC) (control group); UC plus single dose of Sarilumab 200 mg (Sarilumab-200 group) or UC plus single dose of Sarilumab 400 mg (Sarilumab-400 group). Patients who had baseline serum samples for cytokine determination (IL-8, IL-10, MCP-1, IP-10) were included in this secondary analysis. Progression to ARDS according to cytokine levels and treatment received was evaluated.

Results

101 (88%) of 115 patients enrolled in the SARICOR trial had serum samples (control group: n=33; Sarilumab-200: n=33; Sarilumab-400 n=35). Among all evaluated biomarkers, IP-10 showed the strongest association with treatment outcome. Patients with IP-10 ≥ 2500 pg/ml treated with Sarilumab-400 had a lower probability of progression (13%) compared to the control group (58%) (HR 0.19; 95% CI: 0.04-0.90; p=0.04). Conversely, patients with IP-10 &lt; 2500 pg/ml did not show these differences.

Conclusions

IP-10 may predict progression to ARDS in patients with COVID-19 pneumonia and IL-6 levels &gt; 40 pg/ml. Importantly, IP-10 value &lt; 2500 pg/ml might discriminate those individuals who might not benefit of Sarilumab therapy besides high IL-6 levels.

Risk factors for infections caused by carbapenem-resistant Enterobacterales: an international matched case-control-control study (EURECA)

BACKGROUND

Data on risk factors for carbapenem-resistant Enterobacterales (CRE) with wider applicability are needed to inform preventive measures and efficient design of randomised trials.

METHODS

An international matched case-control-control study was performed in 50 hospitals with high CRE incidence from March 2016 to November 2018 to investigate different aspects of infections caused by CRE (NCT02709408). Cases were patients with complicated urinary tract infection (cUTI), complicated intraabdominal (cIAI), pneumonia or bacteraemia from other sources (BSI-OS) due to CRE; control groups were patients with infection caused by carbapenem-susceptible Enterobacterales (CSE), and by non-infected patients, respectively. Matching criteria included type of infection for CSE group, ward and duration of hospital admission. Conditional logistic regression was used to identify risk factors.

FINDINGS

Overall, 235 CRE case patients, 235 CSE controls and 705 non-infected controls were included. The CRE infections were cUTI (133, 56.7%), pneumonia (44, 18.7%), cIAI and BSI-OS (29, 12.3% each). Carbapenemase genes were found in 228 isolates: OXA-48/like, 112 (47.6%), KPC, 84 (35.7%), and metallo-β-lactamases, 44 (18.7%); 13 produced two. The risk factors for CRE infection in both type of controls were (adjusted OR for CSE controls; 95% CI; p value) previous colonisation/infection by CRE (6.94; 2.74-15.53; <0.001), urinary catheter (1.78; 1.03-3.07; 0.038) and exposure to broad spectrum antibiotics, as categorical (2.20; 1.25-3.88; 0.006) and time-dependent (1.04 per day; 1.00-1.07; 0.014); chronic renal failure (2.81; 1.40-5.64; 0.004) and admission from home (0.44; 0.23-0.85; 0.014) were significant only for CSE controls. Subgroup analyses provided similar results.

INTERPRETATION

The main risk factors for CRE infections in hospitals with high incidence included previous colonization, urinary catheter and exposure to broad spectrum antibiotics.

FUNDING

The study was funded by the Innovative Medicines Initiative Joint Undertaking (https://www.imi.europa.eu/) under Grant Agreement No. 115620 (COMBACTE-CARE).

Cytomegalovirus in the transplant setting: Where are we now and what happens next? A report from the International CMV Symposium 2021

The CMV Symposium in September 2021 was an international conference dedicated to cytomegalovirus (CMV) infection after solid organ or hematopoietic stem cell transplantation. This review provides an overview of the presentations given by the expert faculty, supplemented with educational clinical cases. Topics discussed include CMV epidemiology and diagnosis, the burden of CMV infection and disease, CMV-specific immunity and management of CMV in transplant settings. Major advances in the prevention and treatment of CMV in the past decade and increased understanding of CMV immunity have led to improved patient outcomes. In the future, management algorithms may be individualized based on the transplant recipient's immune profile, which will mark the start of a new era for patients with CMV.

Prognostic Significance of the Relative Load of KPC-Producing Klebsiella pneumoniae within the Intestinal Microbiota in a Prospective Cohort of Colonized Patients

Increased relative bacterial load of KPC-producing Klebsiella pneumoniae (KPC-KP) within the intestinal microbiota has been associated with KPC-KP bacteremia. Prospective observational study of KPC-KP adult carriers with a hospital admission at recruitment or within the three prior months (January 2018 to February 2019). A qPCR-based assay was developed to measure the relative load of KPC-KP in rectal swabs (RLKPC, proportion of blaKPC relative to 16S rRNA gene copy number). We generated Fine-Gray competing risk and Cox regression models for survival analysis of all-site KPC-KP infection and all-cause mortality, respectively, at 90 and 30 days. The median RLKPC at baseline among 80 KPC-KP adult carriers was 0.28% (range 0.001% to 2.70%). Giannella Risk Score (GRS) was independently associated with 90-day and 30-day all-site infection (adjusted subdistribution hazard ratio [aHR] 1.23, 95% CI = 1.15 to 1.32, P < 0.001). RLKPC (adjusted hazard ratio [aHR] 1.04, 95% CI = 1.01 to 1.07, P = 0.008) and age (aHR 1.05, 95% CI = 1.01 to 1.10, P = 0.008) were independent predictors of 90-day all-cause mortality in a Cox model stratified by length of hospital stay (LOHS) ≥20 days. An adjusted Cox model for 30-day all-cause mortality, stratified by LOHS ≥14 days, included RLKPC (aHR 1.03, 95% CI = 1.00 to 1.06, P = 0.027), age (aHR 1.10, 95% CI = 1.03 to 1.18, P = 0.004), and severe KPC-KP infection (INCREMENT-CPE score >7, aHR 2.96, 95% CI = 0.97 to 9.07, P = 0.057). KPC-KP relative intestinal load was independently associated with all-cause mortality in our clinical setting, after adjusting for age and severe KPC-KP infection. Our study confirms the utility of GRS to predict infection risk in patients colonized by KPC-KP. IMPORTANCE The rapid dissemination of carbapenemase-producing Enterobacterales represents a global public health threat. Increased relative load of KPC-producing Klebsiella pneumoniae (KPC-KP) within the intestinal microbiota has been associated with an increased risk of bloodstream infection by KPC-KP. We developed a qPCR assay for quantification of the relative KPC-KP intestinal load (RLKPC) in 80 colonized patients and examined its association with subsequent all-site KPC-KP infection and all-cause mortality within 90 days. Giannella Risk Score, which predicts infection risk in colonized patients, was independently associated with the development of all-site KPC-KP infection. RLKPC was not associated with all-site KPC-KP infection, possibly reflecting the large heterogeneity in patient clinical conditions and infection types. RLKPC was an independent predictor of all-cause mortality within 90 and 30 days in our clinical setting. We hypothesize that KPC-KP load may behave as a surrogate marker for the severity of the patient's clinical condition.

Current Positioning against Severe Infections Due to Klebsiella pneumoniae in Hospitalized Adults

Infections due to Klebsiella pneumoniae have been increasing in intensive care units (ICUs) in the last decade. Such infections pose a serious problem, especially when antimicrobial resistance is present. We created a task force of experts, including specialists in intensive care medicine, anaesthesia, microbiology and infectious diseases, selected on the basis of their varied experience in the field of nosocomial infections, who conducted a comprehensive review of the recently published literature on the management of carbapenemase-producing Enterobacterales (CPE) infections in the intensive care setting from 2012 to 2022 to summarize the best available treatment. The group established priorities regarding management, based on both the risk of developing infections caused by K. pneumoniae and the risk of poor outcome. Moreover, we reviewed and updated the most important clinical entities and the new antibiotic treatments recently developed. After analysis of the priorities outlined, this group of experts established a series of recommendations and designed a management algorithm.

Community-acquired bacteremia by Klebsiella pneumoniae producing KPC-3 and resistant to ceftazidime/avibactam

OBJECTIVES

To describe the clinical and microbiological features of a case of community-acquired infection by KPC-producing K. pneumoniae (KPCKP) resistant to ceftazidime/avibactam (CAZ-AVI).

METHODS

Identification of microorganisms was performed with MALDI Biotyper CA System (BrukerDaltonics, Madrid, Spain). Antimicrobial susceptibility testing was performed using Sensitre EURGNCOL panels (Thermo Fisher Scientific, Madrid, Spain) and gradient strips (Etest, bioMérieux, Madrid, Spain) in the case of CAZ-AVI, using EUCAST breakpoints for interpretation. Whole Genome Sequencing of blood culture and rectal swab isolates was performed using the Illumina NovaSeq 6000 sequencing system, with 2 × 150-bp paired-end reads (Illumina Inc).

RESULTS

Blood culture and rectal swab KPCKP isolates were resistant to carbapenems and to CAZ-AVI. The blood culture isolate showed susceptibility to trimethoprim-sulfamethoxazole (TMP-SMX) but the rectal swab culture isolate was resistant to this antibiotic. Both isolates belonged to clonal lineage ST512, harboured a single copy of bla_KPC-3 gene, and showed 16 Single Nucleotide Polymorphism (SNP) between them and 38 SNPs with regards to the first KPC-3 producing K. pneumoniae isolated in our hospital in an initial outbreak in 2012. Genome-wide resistome analysis revealed the presence of a IncFIB(K) plasmid harbouring sul1 and dfrA12 genes only in the rectal swab culture isolate, which may explain its resistance to TMP-SMX.

CONCLUSIONS

Resistance to ceftazidime-avibactam is an emerging nosocomial problem. This case shows that CAZ-AVI-resistant KPCKP strains may disseminate into the community and cause serious infections.

Recommendations for prevention of infection in systemic autoimmune rheumatic diseases

OBJECTIVES

To develop recommendations for the prevention of infection in adult patients with systemic autoimmune rheumatic diseases (SARD).

METHODS

Clinical research questions relevant to the objective of the document were identified by a panel of experts selected based on their experience in the field. Systematic reviews of the available evidence were conducted, and evidence was graded according to the Scottish Intercollegiate Guidelines Network criteria. Specific recommendations were made.

RESULTS

Five questions were selected, referring to prevention of infection by Pneumocystis jirovecii with trimethoprim/sulfamethoxazole, primary and secondary prophylactic measures against hepatitis B virus, vaccination against human papillomavirus, vaccination against Streptococcus pneumoniae and vaccination against influenza virus, making a total of 18 recommendations, structured by question, based on the evidence found for the different SARD and/or expert consensus.

CONCLUSIONS

There is enough evidence on the safety and efficacy of vaccinations and other prophylactic measures against the microorganisms reviewed in this document to specifically recommend them for patients with SARD.

In vivo selection of KPC-94 and KPC-95 in Klebsiella pneumoniae isolates from patients treated with ceftazidime-avibactam

BACKGROUND

Ceftazidime-avibactam (CZA) is used to treat infections caused by KPC-producing Klebsiella pneumoniae (KPC-Kp). Resistance to CZA is commonly related to point mutations in the bla_KPC gene.

OBJECTIVES

We describe the in vivo emergence of CZA resistance in clinical isolates of KPC-Kp from four patients treated with this combination therapy.

METHODS

Four pre-therapy and five post-therapy isolates were examined. Antibiogram (microdilution; gradient strips) and whole genome sequencing were performed. The role of KPC mutations was validated by cloning bla_KPC genes into competent E. coli.

RESULTS

All isolates recovered before treatment with CZA were susceptible to CZA and produced KPC-3. Five KPC-Kp isolates recovered after treatment were resistant to this combination. Three post-therapy isolates from two patients produced KPC-31 (D179Y mutation). Additionally, we identified the novel substitution LN169-170H (KPC-94) in one isolate and the combination in another isolate of two independently described mutations, D179Y and A172T (KPC-95). All KPC-producing K. pneumoniae isolates belonged to ST512. All CZA-resistant isolates with bla_KPC variants had restoration of carbapenem susceptibility.

CONCLUSIONS

Resistance to CZA was related to bla_KPC mutations, including the new KPC-94 and KPC-95 alleles, which did not cause carbapenem resistance.

Propensity Score and Desirability of Outcome Ranking Analysis of Ertapenem for Treatment of Nonsevere Bacteremic Urinary Tract Infections Due to Extended-Spectrum-Beta-Lactamase-Producing Enterobacterales in Kidney Transplant Recipients

There are scarce data on the efficacy of ertapenem in the treatment of bacteremia due to extended-spectrum-beta-lactamase (ESBL)-producing Enterobacterales (ESBL-E) in kidney transplant (KT) recipients. We evaluated the association between treatment with ertapenem or meropenem and clinical cure in KT recipients with nonsevere bacteremic urinary tract infections (B-UTI) caused by ESBL-E. We performed a registered, retrospective, international (29 centers in 14 countries) cohort study (INCREMENT-SOT, NCT02852902). The association between targeted therapy with ertapenem versus meropenem and clinical cure at day 14 (the principal outcome) was studied by logistic regression. Propensity score matching and desirability of outcome ranking (DOOR) analyses were also performed. A total of 201 patients were included; only 1 patient (treated with meropenem) in the cohort died. Clinical cure at day 14 was reached in 45/100 (45%) and 51/101 (50.5%) of patients treated with ertapenem and meropenem, respectively (adjusted OR 1.29; 95% CI 0.51 to 3.22; P = 0.76); the propensity score-matched cohort included 55 pairs (adjusted OR for clinical cure at day 14, 1.18; 95% CI 0.43 to 3.29; P = 0.74). In this cohort, the proportion of cases treated with ertapenem with better DOOR than with meropenem was 49.7% (95% CI, 40.4 to 59.1%) when hospital stay was considered. It ranged from 59 to 67% in different scenarios of a modified (weights-based) DOOR sensitivity analysis when potential ecological advantage or cost was considered in addition to outcome. In conclusion, targeted therapy with ertapenem appears as effective as meropenem to treat nonsevere B-UTI due to ESBL-E in KT recipients and may have some advantages.

Seven-versus 14-day course of antibiotics for the treatment of bloodstream infections by Enterobacterales: a randomized, controlled trial

OBJECTIVE

To prove that 7-day courses of antibiotics for bloodstream infections caused by members of the Enterobacterales (eBSIs) allow a reduction in patients' exposure to antibiotics while achieving clinical outcomes similar to those of 14-day schemes.

METHODS

A randomized trial was performed. Adult patients developing eBSI with appropriate source control were assigned to 7 or 14 days of treatment, and followed 28 days after treatment cessation; treatments could be resumed whenever necessary. The primary endpoint was days of treatment at the end of follow-up. Clinical outcomes included clinical cure, relapse of eBSI and relapse of fever. A superiority margin of 3 days was set for the primary endpoint, and a non-inferiority margin of 10% was set for clinical outcomes. Efficacy and safety were assessed together with a DOOR/RADAR (desirability of outcome ranking and response adjusted for duration of antibiotic risk) analysis.

RESULTS

248 patients were assigned to 7 (n = 119) or 14 (n = 129) days of treatment. In the intention-to-treat analysis, median days of treatment at the end of follow-up were 7 and 14 days (difference 7, 95%CI 7-7). The non-inferiority margin was also met for clinical outcomes, except for relapse of fever (-0.2%, 95%CI -10.4 to 10.1). The DOOR/RADAR showed that 7-day schemes had a 77.7% probability of achieving better results than 14-day treatments.

CONCLUSIONS

7-day schemes allowed a reduction in antibiotic exposure of patients with eBSI while achieving outcomes similar to those of 14-day schemes. The possibility of relapsing fever in a limited number of patients, without relevance to final outcomes, may not be excluded, but was overcome by the benefits of shortening treatments.

Recommendations for prevention of infection in systemic autoimmune rheumatic diseases

OBJECTIVES

To develop recommendations for the prevention of infection in adult patients with systemic autoimmune rheumatic diseases (SARD).

METHODS

Clinical research questions relevant to the objective of the document were identified by a panel of experts selected based on their experience in the field. Systematic reviews of the available evidence were conducted, and evidence was graded according to the Scottish Intercollegiate Guidelines Network criteria. Specific recommendations were made.

RESULTS

Five questions were selected, referring to prevention of infection by Pneumocystis jirovecii with trimethoprim/sulfamethoxazole, primary and secondary prophylactic measures against hepatitis B virus, vaccination against human papillomavirus, vaccination against Streptococcus pneumoniae and vaccination against influenza virus, making a total of 18 recommendations, structured by question, based on the evidence found for the different SARD and/or expert consensus.

CONCLUSIONS

There is enough evidence on the safety and efficacy of vaccinations and other prophylactic measures against the microorganisms reviewed in this document to specifically recommend them for patients with SARD.

Immunoguided Discontinuation of Prophylaxis for Cytomegalovirus Disease in Kidney Transplant Recipients Treated with Antithymocyte Globulin: A Randomized Clinical Trial

BACKGROUND

Antiviral prophylaxis is recommended in cytomegalovirus (CMV)-seropositive kidney transplant (KT) recipients receiving antithymocyte globulin (ATG) as induction. An alternative strategy of premature discontinuation of prophylaxis after CMV-specific cell-mediated immunity (CMV-CMI) recovery (immunoguided prevention) has not been studied. The aim of this study was to evaluate whether it is effective and safe to discontinue prophylaxis when CMV-CMI is detected and to continue with preemptive therapy.

METHODS

In this open-label, non-inferiority clinical trial, patients were randomized 1:1 to follow immunoguided strategy, receiving prophylaxis (valganciclovir 900 mg daily) until CMV-CMI recovery or to receive fixed-duration prophylaxis until day +90. After prophylaxis, preemptive therapy (valganciclovir 900 mg twice daily) was indicated in both arms until month 6. The primary and secondary outcomes were incidence of CMV disease and replication, respectively, within the first 12 months. Desirability of outcome ranking (DOOR) assessed two deleterious events (CMV disease/replication and neutropenia).

RESULTS

A total of 150 CMV-seropositive KT recipients were randomly assigned. There was no difference in the incidence of CMV disease (0% vs. 2.7%; P = 0.149) and replication (17.1% vs. 13.5%; log-rank test, P = 0.422) between both arms. Incidence of neutropenia was lower in the immunoguided arm (9.2% vs. 37.8%; OR, 6.0; P < 0.001). A total of 66.1% of patients in the immunoguided arm showed a better DOOR, indicating a greater likelihood of a better outcome.

CONCLUSIONS

Prophylaxis can be prematurely discontinued in CMV-seropositive KT patients receiving ATG when CMV-CMI is recovered since no significant increase in the incidence of CMV replication or disease is observed.

Human cytomegalovirus (HCMV)-encoded microRNAs: potential biomarkers and clinical applications

HCMV-encoded microRNAs (hcmv-miRNAs) are non-coding and non-immunogenic molecules that target numerous cellular genes and allow the virus to modulate the host's signalling pathways, thus favouring viral survival and replication. Given their capacity to silence the human genes involved in various physiological processes, these hcmv-miRNAs have now emerged as a potential clinical biomarker in many human diseases. In this review, we summarize the evidence published on the diagnostic and prognostic value of hcmv-miRNAs in several human diseases and their clinical implications. Specifically, we discuss the role of hcmv-miRNAs in the development of cardiovascular diseases and cancer by silencing tumour suppressors. We also examine the current knowledge on the utility of some hcmv-miRNAs in predicting HCMV viraemia recurrence in transplant patients, as well as the interference of hcmv-miRNAs in the development of an appropriate immune response against other viral infections, which might have therapeutic implications.

Impact of an Antimicrobial Stewardship Program on the Incidence of Carbapenem Resistant Gram-Negative Bacilli: An Interrupted Time-Series Analysis

Carbapenem-resistant Gram-negative bacilli (CR-GNB) are a critical public health threat, and carbapenem use contributes to their spread. Antimicrobial stewardship programs (ASPs) have proven successful in reducing antimicrobial use. However, evidence on the impact of carbapenem resistance remains unclear. We evaluated the impact of a multifaceted ASP on carbapenem use and incidence of CR-GNB in a high-endemic hospital. An interrupted time-series analysis was conducted one year before and two years after starting the ASP to assess carbapenem consumption, CR-GNB incidence, death rates of sentinel events, and other variables potentially related to CR-GNB incidence. An intense reduction in carbapenem consumption occurred after starting the intervention and was sustained two years later (relative effect -83.51%; 95% CI -87.23 to -79.79). The incidence density of CR-GNB decreased by -0.915 cases per 1000 occupied bed days (95% CI -1.743 to -0.087). This effect was especially marked in CR-Klebsiella pneumoniae and CR-Escherichia coli, reversing the pre-intervention upward trend and leading to a relative reduction of -91.15% (95% CI -105.53 to -76.76) and -89.93% (95% CI -107.03 to -72.83), respectively, two years after starting the program. Death rates did not change. This ASP contributed to decreasing CR-GNB incidence through a sustained reduction in antibiotic use without increasing mortality rates.

Clinical characteristics and outcome of bacteraemia caused by Enterobacter cloacae and Klebsiella aerogenes: more similarities than differences

OBJECTIVES

The genus Enterobacter is a common cause of nosocomial infections. Historically, the most frequent Enterobacter species were those of Enterobacter cloacae complex and Enterobacter aerogenes. In 2019, E. aerogenes was re-classified as Klebsiella aerogenes owing to its higher genotypic similarity with the genus Klebsiella. Our objective was to characterise and compare the clinical profiles of bacteraemia caused by E. cloacae and K. aerogenes.

METHODS

This 3-year multicentre, prospective cohort study enrolled consecutive patients with bacteraemia by E. cloacae or K. aerogenes. Baseline characteristics, bacteraemia features (source, severity, treatment), antibiotic susceptibility, resistance mechanisms and mortality were analysed.

RESULTS

The study included 285 patients with bacteraemia [196 (68.8%) E. cloacae and 89 (31.2%) K. aerogenes]. The groups showed no differences in age, sex, previous use of invasive devices, place of acquisition, sources or severity at onset. The Charlson score was higher among patients with E. cloacae bacteraemia [2 (1-4) vs. 1 (0.5-3); P = 0.018], and previous antibiotic therapy was more common in patients with K. aerogenes bacteraemia (57.3% vs. 41.3%; P = 0.01). Mortality was 19.4% for E. cloacae and 20.2% for K. aerogenes (P = 0.869). Antibiotic susceptibility was similar for both species, and the incidence of multidrug resistance or ESBL production was low (6% and 5.3%, respectively), with no differences between species.

CONCLUSION

Bacteraemias caused by E. cloacae and K. aerogenes share similar patient profiles, presentation and prognosis. Patients with E. cloacae bacteraemia had more co-morbidities and those with K. aerogenes bacteraemia had received more antibiotics.

Effect of Influenza Vaccination Inducing Antibody Mediated Rejection in Solid Organ Transplant Recipients

Introduction

Our goal was to study whether influenza vaccination induced antibody mediated rejection in a large cohort of solid organ transplant recipients (SOTR).

Methods

Serum anti-Human Leukocyte Antigen (HLA) antibodies were determined using class I and class II antibody-coated latex beads (FlowPRA^TM Screening Test) by flow cytometry. Anti-HLA antibody specificity was determined using the single-antigen bead flow cytometry (SAFC) assay and assignation of donor specific antibodies (DSA) was performed by virtual-crossmatch.

Results

We studied a cohort of 490 SOTR that received an influenza vaccination from 2009 to 2013: 110 (22.4%) received the pandemic adjuvanted vaccine, 59 (12%) within the first 6 months post-transplantation, 185 (37.7%) more than 6 months after transplantation and 136 (27.7%) received two vaccination doses. Overall, no differences of anti-HLA antibodies were found after immunization in patients that received the adjuvanted vaccine, within the first 6 months post-transplantation, or based on the type of organ transplanted. However, the second immunization dose increased the percentage of patients positive for anti-HLA class I significantly compared with patients with one dose (14.6% vs. 3.8%; P = 0.003). Patients with pre-existing antibodies before vaccination (15.7% for anti-HLA class I and 15.9% for class II) did not increase reactivity after immunization. A group of 75 (14.4%) patients developed de novo anti-HLA antibodies, however, only 5 (1.02%) of them were DSA, and none experienced allograft rejection. Only two (0.4%) patients were diagnosed with graft rejection with favorable outcomes and neither of them developed DSA.

Conclusion

Our results suggest that influenza vaccination is not associated with graft rejection in this cohort of SOTR.

Pretransplant CMV-Specific T-Cell Immunity But Not Dose of Antithymocyte Globulin Is Associated With Recovery of Specific Immunity After Kidney Transplantation

BACKGROUND

This is a prospective, multicenter, observational study in cytomegalovirus (CMV)-seropositive kidney transplant recipients with pretransplant CMV-specific cell-mediated immunity (CMV-CMI) receiving antithymocyte globulin (ATG). We aimed to investigate posttransplant CMV-CMI over time and the impact of the dose-dependent ATG.

METHODS

CMV-CMI was assessed at days +30, +45, +60, and +90 after transplantation with the QuantiFERON-CMV assay. A reactive result (interferon-γ [IFN-γ] ≥ 0.2 IU/mL) indicated a positive CMV-CMI.

RESULTS

A total of 78 positive CMV-CMI patients were enrolled in the study, of which 59.5% had a positive CMV-CMI at day +30 and 82.7% at day +90. Multivariate logistic regression analysis showed that ATG dose was not associated with positive CMV-CMI at any point. However, pretransplant IFN-γ level (>12 IU/mL vs ≤12 IU/mL) was associated with positive CMV-CMI at day +30 (odds ratio, 12.9; 95% confidence interval, 3.1-53.3; P < .001). In addition, all the patients who did not recover CMV-CMI at day +90 had a pretransplant IFN-γ level ≤12 IU/mL.

CONCLUSIONS

More than half of CMV-seropositive kidney transplant recipients receiving ATG recover (or maintain) CMV-CMI by the first month after transplantation. The pretransplant IFN-γ level, but not the ATG dose, shows a strong association with the kinetics of this recovery.

Predictors of mortality in solid organ transplant recipients with bloodstream infections due to carbapenemase-producing Enterobacterales: The impact of cytomegalovirus disease and lymphopenia

Treatment of carbapenemase-producing Enterobacterales bloodstream infections in solid organ transplant recipients is challenging. The objective of this study was to develop a specific score to predict mortality in solid organ transplant recipients with carbapenemase-producing Enterobacterales bloodstream infections. A multinational, retrospective (2004-2016) cohort study (INCREMENT-SOT, ClinicalTrials.gov NCT02852902) was performed. The main outcome variable was 30-day all-cause mortality. The INCREMENT-SOT-CPE score was developed using logistic regression. The global cohort included 216 patients. The final logistic regression model included the following variables: INCREMENT-CPE mortality score ≥8 (8 points), no source control (3 points), inappropriate empirical therapy (2 points), cytomegalovirus disease (7 points), lymphopenia (4 points), and the interaction between INCREMENT-CPE score ≥8 and CMV disease (minus 7 points). This score showed an area under the receiver operating characteristic curve of 0.82 (95% confidence interval [CI] 0.76-0.88) and classified patients into 3 strata: 0-7 (low mortality), 8-11 (high mortality), and 12-17 (very-high mortality). We performed a stratified analysis of the effect of monotherapy vs combination therapy among 165 patients who received appropriate therapy. Monotherapy was associated with higher mortality only in the very-high (adjusted hazard ratio [HR] 2.82, 95% CI 1.13-7.06, P = .03) and high (HR 9.93, 95% CI 2.08-47.40, P = .004) mortality risk strata. A score-based algorithm is provided for therapy guidance.

A prospective, multicenter case control study of risk factors for acquisition and mortality in Enterobacter species bacteremia

BACKGROUND

Enterobacter is among the main etiologies of hospital-acquired infections. This study aims to identify the risk factors of acquisition and attributable mortality of Enterobacter bacteremia.

METHODS

Observational, case-control study for risk factors and prospective cohort for outcomes of consecutive cases with Enterobacter bacteremia. This study was conducted in five hospitals in Spain over a three-year period. Matched controls were patients with negative blood cultures and same sex, age, and hospitalization area.

RESULTS

The study included 285 cases and 570 controls. E. cloacae was isolated in 198(68.8%) cases and E. aerogenes in 89(31.2%). Invasive procedures (hemodialysis, nasogastric tube, mechanical ventilation, surgical drainage tube) and previous antibiotics or corticosteroids were independently associated with Enterobacter bacteremia. Its attributable mortality was 7.8%(CI95%2.7-13.4%), being dissimilar according to a McCabe index: non-fatal=3.2%, ultimately fatal=12.9% and rapidly fatal=0.12%. Enterobacter bacteremia remained an independent risk factor for mortality among cases with severe sepsis or septic shock (OR 5.75 [CI95%2.57-12.87], p<0.001), with an attributable mortality of 40.3%(CI95%25.7-53.3). Empiric therapy or antibiotic resistances were not related to the outcome among patients with bacteremia.

CONCLUSIONS

Invasive procedures, previous antibiotics and corticosteroids predispose to acquire Enterobacter bacteremia. This entity increases mortality among fragile patients and those with severe infections. Antibiotic resistances did not affect the outcome.

External validation of the INCREMENT-CPE mortality score in a carbapenem-resistant Klebsiella pneumoniae bacteraemia cohort: the prognostic significance of colistin resistance

External validation of the INCREMENT-CPE risk score (ICS) for 30-day all-cause mortality is needed. There is also scarce information about whether colistin resistance influences the prognosis of carbapenem-resistant Klebsiella pneumoniae (CRKp) bacteraemia. In this study, the ability of ICS to predict all-cause mortality in the KAPECOR cohort was calculated using the area under the receiver operating characteristic (AUROC) curve. The association of colistin resistance with mortality was studied. The ICS showed an AUROC curve of 0.77 (95% CI 0.68-0.86). A cut-off of 8 points showed 96.8% sensitivity and 50.7% specificity. Mortality of low-risk patients was not different in those treated with monotherapy versus combination therapy. However, mortality of high-risk patients treated with combination therapy (37.8%) was significantly lower than in those treated with monotherapy (68.4%) (P = 0.008). To study the prognostic significance of colistin resistance, 83 selected cases of bacteraemia due to colistin-susceptible CRKp were obtained from the INCREMENT cohort for comparison. Colistin resistance could not be shown to be associated with higher mortality in either the high-risk ICS group [adjusted odds ratio (aOR) = 1.56, 95% CI 0.69-3.33; P = 0.29] or in 37 ICS-matched pairs (aOR = 1.38, 95% CI 0.55-3.42; P = 0.49), or in a sensitivity analysis including only KPC isolates (aOR = 1.81, 95% CI 0.73-4.57; P = 0.20), but the precision of estimates was low. These results validate ICS for all-cause mortality and to optimise targeted therapy for CRKp bacteraemia. Colistin resistance was not clearly associated with increased mortality.

Bacteremia in Systemic Lupus Erythematosus in Patients from a Spanish Registry: Risk Factors, Clinical and Microbiological Characteristics, and Outcomes

OBJECTIVE

To describe the incidence of bacteremia in a large multicentric cohort of patients with systemic lupus erythematosus (SLE) and their clinical characteristics and to identify risk factors.

METHODS

All bacteremic episodes from the Spanish RELESSER registry were included. Clinical and laboratory characteristics concerning bacteremia and SLE status, as well as comorbidities at the time of infection, were retrospectively collected. A comparison with sex- and age-matched SLE controls without bacteremia was made. A logistic regression was conducted.

RESULTS

The study included 114 episodes of bacteremia in 83 patients. The incidence rate was 2.7/1000 patient-years. At the time of bacteremia, the median age was 40.5 (range: 8-90) years, and 88.6% of patients were female. The Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index was 4 [interquartile range (IQR) 8]; 41% had an SLE flare (66% severe); Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index was 3 (IQR 4). A comorbidity was recorded in 64% of cases. At the time of bacteremia, 88.6% received corticosteroids (68.6% > 10 mg/day) and 57% immunosuppressors. Gram-negative bacilli, most frequently Escherichia coli (29.8%), caused 52.6% of the episodes. The bacteremia-related mortality was 14% and bacteremia was recurrent in 27.2% of cases. A dose-response relationship was found between corticosteroids and bacteremia risk. In the multivariate analysis, these factors were associated with bacteremia: elevated creatinine (OR 1.31, 95% CI 1.01-1.70; p = 0.045), diabetes (OR 6.01, 95% CI 2.26-15.95; p < 0.001), cancer (OR 5.32, 95% CI 2.23-12.70; p < 0.001), immunosuppressors (OR 6.35, 95% CI 3.42-11.77; p < 0.001), and damage (OR 1.65, 95% CI 1.31-2.09; p < 0.001).

CONCLUSION

Bacteremia occurred mostly in patients with active SLE and was frequently associated with severe flares and corticosteroid use. Recurrence and mortality were high. Immunosuppressors, comorbidities, and disease-related damage were associated with bacteremia.

ESCMID-EUCIC clinical guidelines on decolonization of multidrug-resistant Gram-negative bacteria carriers

SCOPE

The aim of these guidelines is to provide recommendations for decolonizing regimens targeting multidrug-resistant Gram-negative bacteria (MDR-GNB) carriers in all settings.

METHODS

These evidence-based guidelines were produced after a systematic review of published studies on decolonization interventions targeting the following MDR-GNB: third-generation cephalosporin-resistant Enterobacteriaceae (3GCephRE), carbapenem-resistant Enterobacteriaceae (CRE), aminoglycoside-resistant Enterobacteriaceae (AGRE), fluoroquinolone-resistant Enterobacteriaceae (FQRE), extremely drug-resistant Pseudomonas aeruginosa (XDRPA), carbapenem-resistant Acinetobacter baumannii (CRAB), cotrimoxazole-resistant Stenotrophomonas maltophilia (CRSM), colistin-resistant Gram-negative organisms (CoRGNB), and pan-drug-resistant Gram-negative organisms (PDRGNB). The recommendations are grouped by MDR-GNB species. Faecal microbiota transplantation has been discussed separately. Four types of outcomes were evaluated for each target MDR-GNB:(a) microbiological outcomes (carriage and eradication rates) at treatment end and at specific post-treatment time-points; (b) clinical outcomes (attributable and all-cause mortality and infection incidence) at the same time-points and length of hospital stay; (c) epidemiological outcomes (acquisition incidence, transmission and outbreaks); and (d) adverse events of decolonization (including resistance development). The level of evidence for and strength of each recommendation were defined according to the GRADE approach. Consensus of a multidisciplinary expert panel was reached through a nominal-group technique for the final list of recommendations.

RECOMMENDATIONS

The panel does not recommend routine decolonization of 3GCephRE and CRE carriers. Evidence is currently insufficient to provide recommendations for or against any intervention in patients colonized with AGRE, CoRGNB, CRAB, CRSM, FQRE, PDRGNB and XDRPA. On the basis of the limited evidence of increased risk of CRE infections in immunocompromised carriers, the panel suggests designing high-quality prospective clinical studies to assess the risk of CRE infections in immunocompromised patients. These trials should include monitoring of development of resistance to decolonizing agents during treatment using stool cultures and antimicrobial susceptibility results according to the EUCAST clinical breakpoints.

Impact of De-escalation on Prognosis of Patients With Bacteremia due to Enterobacteriaceae: A Post Hoc Analysis From a Multicenter Prospective Cohort

Background

More data are needed about the safety of antibiotic de-escalation in specific clinical situations as a strategy to reduce exposure to broad-spectrum antibiotics. The aims of this study were to investigate predictors of de-escalation and its impact on the outcome of patients with bloodstream infection due to Enterobacteriaceae (BSI-E).

Methods

A post hoc analysis was performed on a prospective, multicenter cohort of patients with BSI-E initially treated with ertapenem or antipseudomonal β-lactams. Logistic regression was used to analyze factors associated with early de-escalation (EDE) and Cox regression for the impact of EDE and late de-escalation (LDE) on 30-day all-cause mortality. A propensity score (PS) for EDE vs no de-escalation (NDE) was calculated. Failure at end of treatment and length of hospital stay were also analyzed.

Results

Overall, 516 patients were included. EDE was performed in 241 patients (46%), LDE in 95 (18%), and NDE in 180 (35%). Variables independently associated with a lower probability of EDE were multidrug-resistant isolates (odds ratio [OR], 0.50 [95% confidence interval {CI}, .30–.83]) and nosocomial infection empirically treated with imipenem or meropenem (OR, 0.35 [95% CI, .14–.87]). After controlling for confounders, EDE was not associated with increased risk of mortality; hazard ratios (HR) (95% CIs) were as follows: general model, 0.58 (.25–1.31); model with PS, 0.69 (.29–1.65); and PS-based matched pairs, 0.98 (.76–1.26). LDE was not associated with mortality. De-escalation was not associated with clinical failure or length of hospital stay.

Conclusions

De-escalation in patients with monomicrobial bacteremia due to Enterobacteriaceae was not associated with a detrimental impact on clinical outcome.

[Invasive aspergillosis in solid organ transplantation]

Solid organ transplant (SOT) recipients have a high risk for developing invasive fungal infections (IFI). Treatment is difficult due to the interaction between the antifungal and immunosuppressant drugs, as well as the risk of hepatotoxicity and kidney failure associated with voriconazole and amphotericinB, respectively. Isavuconazole is a new antifungal triazole agent with excellent oral bioavailability, predictable and linear pharmacokinetics, good tolerance and low adverse effects. It has been approved for the treatment of invasive aspergillosis and mucormycosis. A review is presented of the reported experience in the use of isavuconazole in SOT. According to the published studies, isavuconazole has a significantly lower risk of interaction with tacrolimus, and is less hepatotoxic than voriconazole. Nevertheless, there is a significant variability between patients, and between each type of SOT. Isavuconazole reduces the side effects associated with the treatment of IFI in SOT. It would be of great interest the implementation of future clinical trials with isavuconazole for the treatment and/or prophylaxis of IFI in these patients.

Lack of evidence of association between IFNG and IL28B polymorphisms and QuantiFERON-CMV test results in seropositive transplant patients

The aim of this study was to analyze the relationship between the IFNG +874 T/A and IL28B (rs12979860) C/T polymorphisms and the secretion of IFNG by CD8+ T cells after stimulation with cytomegalovirus (CMV) peptides, measured using QuantiFERON-CMV (QF-CMV) assay. A total of 184 CMV-seropositive solid organ transplant patients (108 kidney, 68 liver and 8 lung) were recruited. Of them, 151 patients were QF-CMV Reactive (IFNG ≥ 0.2 UI/mL) and 33 were Non-reactive. Genotype frequencies in the study population were TT (26.6%), AT (50.0%) and AA (23.4%) for IFNG +874 and CC (52.7%), CT (39.1%) and TT (8.2%) for IL28B (rs12979860). These frequencies did not significantly differ between QF-CMV Reactive and Non-reactive patients. Nor were any significant differences observed in the quantitative IFNG level among the genotypes in either the IFNG or the IL28 genes. When we analyzed whether these polymorphisms had any impact on the risk of CMV replication after transplantation, the adjusted analysis showed no association. In summary, our results showed that IFNG +874 T/A and IL28B (rs12979860) C/T polymorphisms are not associated with the IFNG response to CMV measured by the QuantiFERON-CMV assay, although these results should be confirmed with a higher number of patients.

Regular monitoring of cytomegalovirus-specific cell-mediated immunity in intermediate-risk kidney transplant recipients: predictive value of the immediate post-transplant assessment

OBJECTIVE

Previous studies on monitoring of post-transplant cytomegalovirus (CMV)-specific cell-mediated immunity (CMI) are limited by single-centre designs and disparate risk categories. We aimed to assess the clinical value of a regular monitoring strategy in a large multicentre cohort of intermediate-risk kidney transplant (KT) recipients.

METHODS

We recruited 124 CMV-seropositive KT recipients with no T-cell-depleting induction pre-emptively managed at four Spanish institutions. CMV-specific interferon-γ-producing CD4⁺ and CD8⁺ T cells were counted through the first post-transplant year by intracellular cytokine staining after stimulation with pp65 and immediate early-1 peptides (mean of six measurements per patient). The primary outcome was the occurrence of any CMV event (asymptomatic infection and/or disease). Optimal cut-off values for CMV-specific T cells were calculated at baseline and day 15.

RESULTS

Twelve-month cumulative incidence of CMV infection and/or disease was 47.6%. Patients with pre-transplant CMV-specific CD8⁺ T-cell count <1.0 cells/μL had greater risk of CMV events (adjusted hazard ratio (aHR) 2.84; p 0.054). When the CMI assessment was performed in the immediate post-transplant period (day 15), the presence of <2.0 CD8⁺ T cells/μL (aHR 2.18; p 0.034) or <1.0 CD4⁺ T cells/μL (aHR 2.43; p 0.016) also predicted the subsequent development of a CMV event. In addition, lower counts of CMV-specific CD4⁺ (but not CD8⁺) T cells at days 60 and 180 were associated with a higher incidence of late-onset events.

CONCLUSIONS

Monitoring for CMV-specific CMI in intermediate-risk KT recipients must be regular to reflect dynamic changes in overall immunosuppression and individual susceptibility. The early assessment at post-transplant day 15 remains particularly informative.

Perspective of Spanish medical students regarding undergraduate education in infectious diseases, bacterial resistance and antibiotic use

INTRODUCTION

One of the main tools to optimize antibiotics use is education of prescribers. The aim of this article is to study undergraduate education in the field of infectious diseases, antimicrobial resistance and antibiotic stewardship from the perspective of Spanish medical students.

MATERIAL AND METHODS

An anonymous online questionnaire was distributed among sixth grade students using different channels in Europe, within the ESGAP Student-Prepare survey. The questionnaire included 45 questions about knowledge, attitudes and perceptions about diagnosis, bacterial resistance, use of antibiotics and undergraduate training in infectious diseases. We present here the Spanish results.

RESULTS

A total of 441 surveys were received from 21 medical schools. A total of 374 responses (84.8%) were obtained from the 8 most represented faculties, with a response rate of 28.9%. Most students felt adequately prepared to identify clinical signs of infection (418; 94.8%) and to accurately interpret laboratory tests (382; 86.6%). A total of 178 (40.4%) acknowledged being able to choose an antibiotic with confidence without consulting books or guidelines. Only 107 (24.3%) students considered that they had received sufficient training in judicious use of antibiotics. Regarding learning methods, the discussion of clinical cases, infectious diseases units rotatories and small group workshops were considered the most useful, being evaluated favorably in 76.9%, 76% and 68.8% of the cases.

CONCLUSION

Medical students feel more confident in the diagnosis of infectious diseases than in antibiotic treatment. They also feel the need to receive more training in antibiotics and judicious antibiotic use.

Two Doses of Inactivated Influenza Vaccine Improve Immune Response in Solid Organ Transplant Recipients: Results of TRANSGRIPE 1-2, a Randomized Controlled Clinical Trial

Background

Influenza vaccine effectiveness is not optimal in solid organ transplant recipients (SOTR). We hypothesized that a booster dose might increase it.

Methods

TRANSGRIPE 1-2 is a phase 3, randomized, controlled, multicenter, open-label clinical trial. Patients were randomly assigned (1:1 stratified by study site, type of organ, and time since transplantation) to receive 1 dose (control group) or 2 doses (booster group) of the influenza vaccine 5 weeks apart.

Results

A total of 499 SOTR were enrolled. Although seroconversion at 10 weeks did not meet significance in the modified intention-to-treat population, seroconversion rates were significantly higher in the booster arm for the per-protocol population (53.8% vs 37.6% for influenza A(H1N1)pdm; 48.1% vs 32.3% for influenza A(H3N2); and 90.7% vs 75% for influenza B; P < .05). Furthermore, seroprotection at 10 weeks was higher in the booster group: 54% vs 43.2% for A(H1N1)pdm; 56.9% vs 45.5% for A(H3N2); and 83.4% vs 71.8% for influenza B (P < .05). The number needed to treat to seroprotect 1 patient was <10. The clinical efficacy (99.2% vs 98.8%) and serious adverse events (6.4% vs 7.5%) were similar for both groups.

Conclusions

In SOTR, a booster strategy 5 weeks after standard influenza vaccination is safe and effective and induces an increased antibody response compared with standard influenza vaccination consisting of a single dose.

Clinical Trials Registration

EudraCT (2011-003243-21).

Empiric Therapy With Carbapenem-Sparing Regimens for Bloodstream Infections due to Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae: Results From the INCREMENT Cohort

BACKGROUND

There is little information about the efficacy of active alternative drugs to carbapenems except β-lactam/β-lactamase inhibitors for the treatment of bloodstream infections (BSIs) due to extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E). The objective of this study was to assess the outcomes of patients with BSI due to ESBL-E who received empiric therapy with such drugs (other active drugs [OADs]) or carbapenems.

METHODS

A multinational retrospective cohort study of patients with BSI due to ESBL-E who received empiric treatment with OADs or carbapenems was performed. Cox regression including a propensity score for receiving OADs was performed to analyze 30-day all-cause mortality as main outcome. Clinical failure and length of stay were also analyzed.

RESULTS

Overall, 335 patients were included; 249 received empiric carbapenems and 86 OADs. The most frequent OADs were aminoglycosides (43 patients) and fluoroquinolones (20 patients). Empiric therapy with OADs was not associated with mortality (hazard ratio [HR], 0.75; 95% confidence interval [CI], .38-1.48) in the Cox regression analysis. Propensity score-matched pairs, subgroups, and sensitivity analyses did not show different trends; specifically, the adjusted HR for aminoglycosides was 1.05 (95% CI, .51-2.16). OADs were neither associated with 14-day clinical failure (adjusted odds ratio, 0.62; 95% CI, .29-1.36) nor length of hospital stay.

CONCLUSIONS

We were unable to show that empiric treatment with OAD was associated with a worse outcome compared with carbapenems. This information allows more options to be considered for empiric therapy, at least for some patients, depending on local susceptibility patterns of ESBL-E.

Development and validation of the INCREMENT-ESBL predictive score for mortality in patients with bloodstream infections due to extended-spectrum-β-lactamase-producing Enterobacteriaceae

Background

Bloodstream infections (BSIs) due to ESBL-producing Enterobacteriaceae (ESBL-E) are frequent yet outcome prediction rules for clinical use have not been developed. The objective was to define and validate a predictive risk score for 30 day mortality.

Methods

A multinational retrospective cohort study including consecutive episodes of BSI due to ESBL-E was performed; cases were randomly assigned to a derivation cohort (DC) or a validation cohort (VC). The main outcome variable was all-cause 30 day mortality. A predictive score was developed using logistic regression coefficients for the DC, then tested in the VC.

Results

The DC and VC included 622 and 328 episodes, respectively. The final multivariate logistic regression model for mortality in the DC included age >50 years (OR = 2.63; 95% CI: 1.18-5.85; 3 points), infection due to Klebsiella spp. (OR = 2.08; 95% CI: 1.21-3.58; 2 points), source other than urinary tract (OR = 3.6; 95% CI: 2.02-6.44; 3 points), fatal underlying disease (OR = 3.91; 95% CI: 2.24-6.80; 4 points), Pitt score >3 (OR = 3.04; 95 CI: 1.69-5.47; 3 points), severe sepsis or septic shock at presentation (OR = 4.8; 95% CI: 2.72-8.46; 4 points) and inappropriate early targeted therapy (OR = 2.47; 95% CI: 1.58-4.63; 2 points). The score showed an area under the receiver operating curve (AUROC) of 0.85 in the DC and 0.82 in the VC. Mortality rates for patients with scores of < 11 and ≥11 were 5.6% and 45.9%, respectively, in the DC, and 5.4% and 34.8% in the VC.

Conclusions

We developed and validated an easy-to-collect predictive scoring model for all-cause 30 day mortality useful for identifying patients at high and low risk of mortality.

Clinical predictors of methicillin-resistant Staphylococcus aureus in nosocomial and healthcare-associated pneumonia: a multicenter, matched case-control study

The situations in which coverage for methicillin-resistant Staphylococcus aureus (MRSA) in the empirical treatment of nosocomial pneumonia (NP) or severe healthcare-associated pneumonia (HCAP) is needed are poorly defined, particularly outside intensive care units (ICUs). Our aim was to characterize if the risk of MRSA NP/HCAP can be defined by clinical variables. We designed an observational, retrospective, multicenter, case-control study to analyze the association between defined clinical variables and risk of MRSA NP/HCAP in non-ICU patients using conditional multivariable logistic regression. Cases and controls (1:2) with microbiological diagnosis were included. Controls were matched for hospital, type of pneumonia (NP or HCAP), and date of isolation. A total of 140 cases (77 NP and 63 HCAP) and 280 controls were studied. The variables associated with the risk of MRSA pneumonia were: (i) respiratory infection/colonization caused by MRSA in the previous year [odds ratio (OR) 14.81, 95% confidence interval (CI) 4.13-53.13, p < 0.001]; (ii) hospitalization in the previous 90 days (OR 2.41, 95% CI 1.21-4.81, p = 0.012); and (iii) age (OR 1.02, 95% CI 1.001-1.05, p = 0.040). The area under the receiver operating characteristic (ROC) curve for the multivariable model was 0.72 (95% CI 0.66-0.78). The multivariate model had a sensitivity of 74.5% (95% CI 65.3-83.6), a specificity of 63.3% (95% CI 56.0-70.6), a positive predictive value of 52.5% (95% CI 43.9-61.2), and a negative predictive value of 82.0% (95% CI 75.3-88.8) for the observed data. Clinical predictors of MRSA NP/HCAP can be used to define a low-risk population in whom coverage against MRSA may not be needed.

Impact of age and cytomegalovirus on CD8+ T-cell compartment remodeling after solid organ transplantation: A one-year follow-up study

Cytomegalovirus (CMV), a member of the β-herpesvirus family, is a major complicating infection in transplant patients. CMV latency has a long-term impact on CD8⁺ T-cell differentiation. It is unclear, however, whether this effect can be detected in one-year period. To investigate this, we analyzed the remodeling of the CD8⁺ T-cell compartment during the first year after solid organ transplantation. A total of 55 kidney or lung transplant patients were recruited. CD8⁺ T-cell subsets were prospectively analyzed at pretransplant, at 3 or 6months and 12months after transplantation (mo post-Tx). A significant increase in the frequency of CD27^-CD28^-CD8⁺ T cells (from 32.8% to 42.3%; p=0.014) was observed from pretransplant to 12mo post-Tx. Further analysis, however, showed that the largest expansion was observed from 3/6 to 12mo post-Tx whereas small non-significant variations were observed from pretransplant to 3/6mo post-Tx. The adjusted analysis showed that age and CMV seropositivity were statistically associated with the baseline frequency of CD27^-CD28^-CD8⁺ T cells. Additionally, CMV replication was related to the posttransplant expansion of this subpopulation, since it was not observed in patients without CMV viremia (24% vs. 4.2%). The results indicate that the expanded frequency associated with late CMV replication is additive to the baseline frequency related to aging and CMV seropositivity. If the expanded frequency remains at this high level for a long period it might have clinical consequences related to the control of future reactivations of CMV or of other related viruses.

Detection of cytomegalovirus drug resistance mutations in solid organ transplant recipients with suspected resistance

BACKGROUND

Current guidelines recommend that treatment of resistant cytomegalovirus (CMV) in solid organ transplant (SOT) recipients must be based on genotypic analysis. However, this recommendation is not systematically followed.

OBJECTIVES

To assess the presence of mutations associated with CMV resistance in SOT recipients with suspected resistance, their associated risk factors and the clinical impact of resistance.

STUDY DESIGN

Using Sanger sequencing we prospectively assessed the presence of resistance mutations in a nation-wide prospective study between September 2013-August 2015.

RESULTS

Of 39 patients studied, 9 (23%) showed resistance mutations. All had one mutation in the UL 97 gene and two also had one mutation in the UL54 gene. Resistance mutations were more frequent in lung transplant recipients (44% p=0.0068) and in patients receiving prophylaxis ≥6 months (57% vs. 17%, p=0.0180). The mean time between transplantation and suspicion of resistance was longer in patients with mutations (239 vs. 100days, respectively, p=0.0046) as was the median treatment duration before suspicion (45 vs. 16days, p=0.0081). There were no significant differences according to the treatment strategies or the mean CMV load at the time of suspicion. Of note, resistance-associated mutations appeared in one patient during CMV prophylaxis and also in a seropositive organ recipient. Incomplete suppression of CMV was more frequent in patients with confirmed resistance.

CONCLUSIONS

Our study confirms the need to assess CMV resistance mutations in any patient with criteria of suspected clinical resistance. Early confirmation of the presence of resistance mutations is essential to optimize the management of these patients.

Rural habitat as risk factor for hepatitis E virus seroconversion in HIV-infected patients: A prospective longitudinal study

Our objective was to determine the incidence and clinical manifestations of acute hepatitis E virus (HEV) in HIV-infected patients. A prospective longitudinal study including HIV-infected HEV-seronegative patients was conducted; HEV seroconversion (to IgG and/or IgM) was the main outcome variable. All patients were tested for HEV antibodies every 3-6 months. For patients who developed HEV seroconversion, a data collection protocol was followed to identify associated clinical manifestations and analytical alterations. A total of 627 patients (89.9%) were followed during a median of 11.96 months (IQR: 8.52-14.52 months) and formed the study population. Forty-one patients developed detectable anti-HEV antibodies (7.2 cases per 100 patients/year). Our study found a high incidence of HEV in HIV-infected patients in southern Spain strongly associated with a rural habitat.

Risk of tuberculosis after lung transplantation: the value of pretransplant chest computed tomography and the impact of mTOR inhibitors and azathioprine use

BACKGROUND

It is necessary to determine the incidence and risk factors for tuberculosis (TB), as well as strategies to assess and treat latent tuberculosis infection (LTBI) in lung transplant recipients.

METHODS

A retrospective cohort study of 398 lung transplant recipients was performed. Episodes of TB were studied and the incidence rate was calculated. Logistic regression analysis was used to analyze specific variables as potential risk factors for TB.

RESULTS

Median follow-up was 558 days (range 1-6636). Six cases (1.5%) of TB were documented in 398 transplant patients. The incidence density of TB was 406.3 cases/10(5) patient-years (95% confidence interval [CI] 164.7-845), which is higher than in the general population (13.10 cases/10(5) person-years). All cases occurred in the period 1993-2006, when the tuberculin skin test (TST) and treatment of LTBI in positive TST patients were not part of the protocol. Pretransplant computed tomography (CT) showed residual lesions in 50% of patients who developed TB, although the TST was negative and the chest radiograph was inconclusive. Multivariate analysis identified the presence of residual lesions in the pretransplant chest CT (odds ratio [OR] 11.5, 95% CI 1.9-69.1, P = 0.008), use of azathioprine (OR 10.6, 95% CI 1.1-99.1, P = 0.038), and use of everolimus (OR 6.7, 95% CI 1.1-39.8, P = 0.036) as independent risk factors for TB.

CONCLUSIONS

Residual lesions in the pretransplant chest CTs and the use of azathioprine and mTOR inhibitors are associated with the risk of TB.