Perioperative Antibiotic Prophylaxis to Prevent Surgical Site Infections in Solid Organ Transplantation

Lung donor bronchoalveolar lavage positivity: Incidence, risk factors, and lung transplant recipients' outcome

BACKGROUND

Inconsistent data exists regarding the risk factors for bronchoalveolar lavage (BAL) positivity in lung donors, the incidence of donor-derived infections (DDI), and the effect of BAL positivity on lung transplant (LuTx) recipients' outcome.

METHODS

A retrospective analysis was conducted on consecutive LuTx at a single center from January 2016 to December 2022. Donors' data, including characteristics, graft function and BAL samples were collected pre-procurement. Recipients underwent BAL before LuTx and about the 3rd, 7th and 14th day after LuTx. A DDI was defined as BAL positivity (bacterial growth ≥104 colony forming units) for identical bacterial species between donor and recipient. Recipients' pre-operative characteristics, intra-operative management, and post-operative outcomes were assessed. Two recipient cohorts were identified based on lung colonization status before undergoing LuTx.

RESULTS

Out of 188 LuTx procedures performed, 169 were analyzed. Thirty-six percent of donors' BAL tested positive. Donors' characteristics and graft function at procurement were not associated with BAL positivity. Fourteen DDI were detected accounting for 23% of recipients receiving a graft with a positive BAL. Only among uncolonized recipients, receiving a graft with positive BAL is associated with higher likelihood of requiring invasive ventilation at 72 hours after LuTx on higher positive end-expiratory pressure levels having lower PaO2/FiO2, prolonged duration of mechanical ventilation and longer ICU stay. No difference in hospital length of stay was observed.

CONCLUSIONS

Receiving a graft with a positive BAL, which is poorly predicted by donors' characteristics, carries the risk of developing a DDI and is associated to a worse early graft function among uncolonized recipients.

Comparative Effectiveness of Perioperative Antibiotic Regimens to Prevent Surgical Site Infections in Pediatric Liver Transplant Recipients

BACKGROUND

Surgical site infections (SSIs) are a common complication in liver transplant (LT) recipients. Lack of pediatric prophylaxis guidelines results in variation in preventative antibiotic regimens.

METHODS

We performed a retrospective observational study of LT recipients <18 years old using a merged data set that included data from the Pediatric Health Information System and the United Network for Organ Sharing between 2006 and 2017. The exposure was defined as the antibiotic(s) received within 24 hours of LT, with 6 categories, ranging from narrow (category 1: cefazolin), to broad). The primary outcome was presence or absence of SSI in the index admission. Mixed-effects logistic regression compared the effectiveness of each category in preventing SSI, relative to category 1.

RESULTS

Of the 2586 LT, 284 (11%) met SSI criteria. The SSI rate was higher in the younger subcohort (16.2%) than in the older (8.6%), necessitating a stratified analysis. Antibiotics from category 5 were most commonly used. In the younger subcohort, the adjusted risk was increased in all categories compared with the reference, most notably in category 3 (odds ratio [OR], 2.58 [95% confidence interval: .69-9.59]) and category 6 (2.76 [.66-11.56]). In the older subcohort, estimated ORs were also increased for each category, most notably in category 4 (2.49 [95% confidence interval: .99-6.27]). None of the ORs suggested benefit from broader-spectrum prophylaxis. Our E-value assessment suggests that it's unlikely there is unmeasured confounding by indication to the degree necessary to revert ORs to protective.

CONCLUSIONS

There was wide variation in antibiotic prophylaxis. Adjusted analyses did not reveal a protective benefit of broader-spectrum prophylaxis in either subcohort, suggesting that narrower regimens may be adequate.

Risk Factors for Surgical-site Infections After Liver Transplant: Does Perioperative Antibiotic Regimen Matter?

BACKGROUND

Surgical-site infections (SSIs) are common in liver transplant recipients. The optimal SSI antimicrobial prophylaxis agent and duration are not established. We aimed to explore risk factors for SSIs after transplant, with a particular interest in the impact of perioperative antibiotic regimen on the development of SSIs.

METHODS

Retrospective study of adults undergoing liver transplant across 3 transplant programs between January 1, 2020, and June 01, 2021.

RESULTS

Of 557 patients included in the study, 32 (5.7%) were infected or colonized with a multidrug-resistant organism (MDRO) within 1 y before liver transplant. Narrow-spectrum SSI prophylaxis with ceftriaxone or cefazolin alone was administered in 488 of 577 patients (87.6%); the remaining 69 patients (12.4%) received broad-spectrum prophylaxis with vancomycin and aztreonam (n = 40), piperacillin-tazobactam (n = 11), carbapenems (n = 8), ceftriaxone and another antibiotic (n = 7), and others. Patients with pretransplant MDRO were more likely to receive broad-spectrum coverage than those without pretransplant MDROs (28.1% versus 11.4%, P  = 0.005). SSIs were identified in 40 patients (7.2%); 25 (62.5%) were organ-space infections, 3 (7.5%) were deep incisional infections, and 12 (30.0%) were superficial incisional infections. The median time from liver transplant to SSIs was 14 d (interquartile range, 10-20.2). MDROs were identified in 12 SSIs (30%). Multivariable analysis revealed no significant association between antimicrobial spectrum and risk of SSIs ( P  = 0.5), whereas surgical leak ( P <0.001) and reoperation ( P  = 0.017) were independently associated with increased risk of SSIs. SSIs were not significantly associated with composite risk of death or liver allograft failure.

CONCLUSIONS

The spectrum of antimicrobial prophylaxis did not impact the development of SSIs in liver transplant recipients.

Bacterial infections in solid organ transplant recipients

PURPOSE OF REVIEW

Bacteria are the leading cause of infections in solid organ transplant (SOT) recipients, significantly impacting patient outcome. Recently detailed and comprehensive epidemiological data have been published.

RECENT FINDING

This literature review aims to provide an overview of bacterial infections affecting different types of SOT recipients, emphasizing underlying risk factors and pathophysiological mechanisms.

SUMMARY

Lung transplantation connects two microbiotas: one derived from the donor's lower respiratory tract with one from the recipient's upper respiratory tract. Similarly, liver transplantation involves a connection to the digestive tract and its microbiota through the bile ducts. For heart transplant recipients, specific factors are related to the management strategies for end-stage heart failure based with different circulatory support tools. Kidney and kidney-pancreas transplant recipients commonly experience asymptomatic bacteriuria, but recent studies have suggested the absence of benefice of routine treatment. Bloodstream infections (BSI) are frequent and affect all SOT recipients. Nonorgan-related risk factors as age, comorbidity index score, and leukopenia contribute to BSI development. Bacterial opportunistic infections have become rare in the presence of efficient prophylaxis. Understanding the epidemiology, risk factors, and pathophysiology of bacterial infections in SOT recipients is crucial for effective management and improved patient outcomes.

Pre-Transplantation Strategies for Infectious Disease Mitigation and Prevention

Pediatric Infectious Disease (ID) clinicians play a critical role in helping prevent and mitigate infectious risks in children peri- and post-transplantation. Prevention starts during the pre-transplant evaluation and persists throughout the solid organ transplant and hematopoietic cell transplant continuum. The pre-transplant evaluation is an opportunity to screen for latent infections, plan preventative strategies, optimize immunizations, and discuss risk mitigation practices. An ideal pre-transplant evaluation establishes a relationship with the family that further promotes post-transplant infectious risk reduction. This manuscript builds on shared pediatric ID prevention strategies, introduces updated ID testing recommendations for transplant donors/candidates, highlights emerging data, and identifies ongoing knowledge gaps that are potential areas of research.

Infection-Related Hospitalizations After Simultaneous Pancreas-Kidney Transplantation Compared to Kidney Transplantation Alone

The total burden of infections after transplantation has not been compared in detail between recipients of simultaneous pancreas-kidney transplantation (SPK) and kidney transplantation alone (KTA). We compared infection-related hospitalizations and bacteremias after transplantation during 1- and 5-year follow-up among 162 patients undergoing SPK. The control group consisted of 153 type 1 diabetics undergoing KTA with the inclusion criteria of donor and recipient age < 60, and BMI < 30. During the first year, SPK patients had more infection-related hospitalizations (0.54 vs. 0.31 PPY, IRR 1.76, p = <0.001) and bacteremias (0.11 vs. 0.01 PPY, IRR 17.12, p = <0.001) compared to KTA patients. The first infection-related hospitalizations and bacteremias occurred later during follow-up in KTA patients. SPK was an independent risk factor for infection-related hospitalization and bacteremia during the first year after transplantation, but not during the 5-year follow-up. Patient survival did not differ between groups, however, KTA patients had inferior kidney graft survival. SPK patients are at greater risk for infection-related hospitalizations and bacteremias during the first year after transplantation compared to KTA patients, however, at the end of the follow-up the risk of infection was similar between groups.

Current Utilization of Antifungal Agents for Intra-abdominal Infections Categorized by Patient Risk Factors During Surgical Procedures: A Literature Review

The high morbidity and mortality rates associated with invasive fungal infections have led to the overutilization of empiric antifungal therapies. With increasing antibiotic resistance, the careful consideration of prophylactic or empiric antifungal use is critical. The purpose of this review is to evaluate the available literature regarding the current practice of utilizing antifungal agents for intra-abdominal infections based on specific surgical procedures and patient risk factors. Relevant articles were identified through a comprehensive literature search of several databases using the keywords antifungal agents, postoperative period, preoperative care, surgical procedures, and intra-abdominal infections. Only articles that evaluated the use of empiric antifungals for suspected or confirmed intra-abdominal infections and surgical procedures were included in this review. Based on the available literature, antifungal prophylaxis is appropriate in patients who meet the criteria for high-risk invasive candidiasis, kidney or liver transplant recipients, severely-immunocompromised patients with perforated peptic ulcer, peritonitis, and patients on peritoneal dialysis who are failing on a therapeutic antibiotic regimen. We acknowledge that the evidence for using antifungal therapy empirically for all surgical procedures is lacking, and the following review is based on available literature and current guidelines.

Early Intra-Abdominal Bacterial Infections after Orthotopic Liver Transplantation: A Narrative Review for Clinicians

Despite recent advances in the transplant field, infectious complications after orthotopic liver transplantation (OLT) are major causes of morbidity and mortality. Bacterial intra-abdominal infections (IAIs) are predominant during the first month post-transplantation and affect patient and graft survival. Recently, the emergence of multidrug resistant bacteria has generated great concern in OLT patients. We performed this narrative review of the literature in order to propose a "ready-to-use" flowchart for reasoned empirical antibiotic therapy in the case of suspected post-OLT IAIs. The review was ultimately organized into four sections: "Epidemiology and predisposing factors for IAI"; "Surgical-site infections and perioperative prophylaxis"; "MDRO colonization and infections"; and "Reasoned-empirical antibiotic therapy in early intra-abdominal infections post OLT and source control". Multidisciplinary teamwork is warranted to individualize strategies for the prevention and treatment of IAIs in OLT recipients, taking into account each patient's risk factors, the surgical characteristics, and the local bacterial epidemiology.

Opportunities for Antimicrobial Stewardship Interventions Among Solid Organ Transplant Recipients

Although antimicrobial stewardship programs have excelled over the past decade, uptake and application of these programs to special populations such as solid organ transplant recipients have lagged. Here, we review the value of antimicrobial stewardship for transplant centers and highlight data supporting interventions that are ripe for adoption. In addition, we review the design of antimicrobial stewardship initiatives, targets for both syndromic and system-based interventions.

Wide-spectrum antibiotic prophylaxis guarantees optimal outcomes in drowned donor kidney transplantation

BACKGROUND

Drowned victims possibly obtain various pathogens from drowning sites. Using drowned renal donors to expand the donor pool still lacks consensus due to the potential risk of disease transmission.

RESEARCH DESIGN AND METHODS

This retrospective study enrolled 38 drowned donor renal recipients in a large clinical center from August 2012 to February 2021. A 1:2 matched cohort was generated with donor demographics, including age, gender, BMI, and ICU durations. Donor microbiological results, recipient perioperative infections, and early post-transplant and first-year clinical outcomes were analyzed.

RESULTS

Compared to the control group, drowned donors had significantly increased positive fungal cultures (36.84% vs.13.15%, p = 0.039). Recipients in the drowned group had significantly higher rates of gram-negative bacteria (GNB) and multidrug-resistant GNB infections (23.68% vs.5.26%, 18.42% vs. 3.95%, both p < 0.05). Other colonization and infections were also numerically more frequent in the drowned group. Drowned donor recipients receiving inadequate antibiotic prophylaxis had more perioperative bloodstream infections, higher DGF incidences, and more first-year respiratory tract infections and recipient loss than those receiving adequate prophylaxis (all p < 0.05). Clinical outcomes were similar between the adequate group and the control group.

CONCLUSIONS

Drowned donors could be suitable options under wide-spectrum and adequate antimicrobial prophylaxis.

ESCMID/EUCIC clinical practice guidelines on perioperative antibiotic prophylaxis in patients colonized by multidrug-resistant Gram-negative bacteria before surgery

SCOPE

The aim of the guidelines is to provide recommendations on perioperative antibiotic prophylaxis (PAP) in adult inpatients who are carriers of multidrug-resistant Gram-negative bacteria (MDR-GNB) before surgery.

METHODS

These evidence-based guidelines were developed after a systematic review of published studies on PAP targeting the following MDR-GNB: extended-spectrum cephalosporin-resistant Enterobacterales, carbapenem-resistant Enterobacterales (CRE), aminoglycoside-resistant Enterobacterales, fluoroquinolone-resistant Enterobacterales, cotrimoxazole-resistant Stenotrophomonas maltophilia, carbapenem-resistant Acinetobacter baumannii (CRAB), extremely drug-resistant Pseudomonas aeruginosa, colistin-resistant Gram-negative bacteria, and pan-drug-resistant Gram-negative bacteria. The critical outcomes were the occurrence of surgical site infections (SSIs) caused by any bacteria and/or by the colonizing MDR-GNB, and SSI-attributable mortality. Important outcomes included the occurrence of any type of postsurgical infectious complication, all-cause mortality, and adverse events of PAP, including development of resistance to targeted (culture-based) PAP after surgery and incidence of Clostridioides difficile infections. The last search of all databases was performed until April 30, 2022. The level of evidence and strength of each recommendation were defined according to the Grading of Recommendations Assessment, Development and Evaluation approach. Consensus of a multidisciplinary expert panel was reached for the final list of recommendations. Antimicrobial stewardship considerations were included in the recommendation development.

RECOMMENDATIONS

The guideline panel reviewed the evidence, per bacteria, of the risk of SSIs in patients colonized with MDR-GNB before surgery and critically appraised the existing studies. Significant knowledge gaps were identified, and most questions were addressed by observational studies. Moderate to high risk of bias was identified in the retrieved studies, and the majority of the recommendations were supported by low level of evidence. The panel conditionally recommends rectal screening and targeted PAP for fluoroquinolone-resistant Enterobacterales before transrectal ultrasound-guided prostate biopsy and for extended-spectrum cephalosporin-resistant Enterobacterales in patients undergoing colorectal surgery and solid organ transplantation. Screening for CRE and CRAB is suggested before transplant surgery after assessment of the local epidemiology. Careful consideration of the laboratory workload and involvement of antimicrobial stewardship teams before implementing the screening procedures or performing changes in PAP are warranted. High-quality prospective studies to assess the impact of PAP among CRE and CRAB carriers performing high-risk surgeries are advocated. Future well-designed clinical trials should assess the effectiveness of targeted PAP, including the monitoring of MDR-GNB colonization through postoperative cultures using European Committee on Antimicrobial Susceptibility Testing clinical breakpoints.

Perioperative antibiotic stewardship in the organ transplant setting

BACKGROUND

Solid organ transplant (SOT) recipients can benefit from traditional antimicrobial stewardship (AMS) activities directed to improve judicious perioperative prescribing and management, but evidence is lacking. The aim of this expert opinion review is to provide an update on the current landscape of application of AMS practices for optimization of perioperative prophylaxis (PP).

METHODS

We reviewed the available literature on early postoperative infectious complications in SOT and PP management, on modified perioperative approaches in case of infection or colonization in recipients and donors and on AMS in transplantation PP.

RESULTS

SOT recipients are at high risk for early postoperative infectious complications due to the complexity of surgical procedures, severity of end stage organ disease, net state of immunosuppression in the posttransplant period and to the high risk for multidrug resistant organism. Moreover, SOT may be exposed to preservation fluid infections and expected or unexpected donor-derived infections. We summarize main factors to take into account when prescribing transplant PP.

CONCLUSION

Creating personalized PP to avoid unwanted consequences of antimicrobials while improving outcomes is an emerging and critical aspect in SOT setting. Further studies are needed to offer best PP tailored to SOT type and to evaluate interventions efficacy and safety.

Beta-lactam allergies, surgical site infections, and prophylaxis in solid organ transplant recipients at a single center: A retrospective cohort study

BACKGROUND

Beta-lactam allergies (BLAs) are common in hospitalized patients, including transplant recipients. BLA is associated with decreased use of preferred surgical site infection (SSI) prophylaxis and increased SSIs, but this has not been studied in the transplant population.

METHODS

We reviewed adult heart, kidney, and liver transplant recipients between January 1, 2016 and December 31, 2019 to characterize reported BLA and collect SSI prophylaxis regimens at time of transplant. We compared the use of preferred SSI prophylaxis and SSI incidence based on reported BLA status. Post hoc we collected antibiotic days of therapy (DOT) (excluding pneumocystis prophylaxis) in the 30-day period posttransplant for patients without SSI. We utilized descriptive statistics for comparisons.

RESULTS

Of 691 patients included (116 heart, 400 kidney, and 175 liver transplant recipients), 118 (17%) reported BLA. Rash and hives were the two most reported BLA reactions (36% and 24%), categorized as potential T-cell mediated and IgE mediated, respectively. Preferred SSI prophylaxis was prescribed in 13 (11%) patients with BLA and 573 (92%) without BLA (p < .001). No difference could be detected in SSI incidence between BLA and non-BLA patients (4.2 vs. 4.3%, p = 1.0). Of 659 without SSI, 169 (25.6%) received antibiotics within 30 days of transplant; mean antibiotic DOT for BLA and non-BLA patients were 3.5 ± 8.0 versus 2.3 ± 5.8, p = .12.

CONCLUSION

BLA transplant recipients received nonpreferred SSI prophylaxis more frequently than non-BLA recipients, but there was no difference in 30-day SSIs between the groups. One-fourth of solid organ transplant recipients received systemic antibiotics within 30 days of transplant.

Outpatient and peri-operative antibiotic stewardship in solid organ transplantation

BACKGROUND

The consequences of inappropriate antimicrobial use including resistance are increasingly recognized as a global public health threat and many steps have been taken over the last few decades to advance antimicrobial stewardship initiatives with most organ transplant centers currently part of institutions with active antimicrobial stewardship programs.

METHODS

A review of the literature was conducted and articles were categorized according to the topic and relevance in the judgment of the two authors.

RESULTS

A summary review of the currently available literature was created with a focus on periprocedural and outpatient antimicrobial stewardship. Limitations in the data were significant and discussed in the review.

CONCLUSION

The principles of antimicrobial stewardship remain important throughout all phases starting with periprocedural prophylactic antimicrobial selection all the way through to discharge and subsequent healthcare encounters. Despite the broad advances in stewardship initiatives and the rapidly progressing supportive data overall there continue to be significant opportunities for additional research within various special patient populations including recipients of solid organ transplantation (SOT). The recent white paper published in the American Journal of Transplantation called to action the transplant and stewardship communities to have an increased focus and awareness of the issues that antimicrobial overuse can present in the SOT patient population. This is an important step that will hopefully generate more data in this group of patients that arguably faces the greatest vulnerability to the consequences of increased antimicrobial resistance.

Carbapenems versus Cephalosporin or Piperacillin-Tazobactam as Perioperative Antibiotic Prophylaxis in Liver Transplant Recipients with Model for End-Stage Liver Disease Scores of ≥30: A Retrospective Study in a Chinese Population

Objective

Perioperative prophylaxis, commonly with a third-generation cephalosporin plus ampicillin or piperacillin-tazobactam, is usually employed to prevent infections in liver transplantation (LT) recipients. Patients with a high Model for End-Stage Liver Disease (MELD) score have an increased infection risk after LT. However, whether carbapenems could be used as surgical prophylaxis in these high-risk patients remains unclear. Therefore, this study aimed at comparing the effectiveness of carbapenems with that of cephalosporin or piperacillin-tazobactam for surgical prophylaxis in high-risk LT recipients with a MELD score ≥30.

Design or Methods

This retrospective study included adult patients with a MELD score ≥30 who underwent LT between May 2018 and September 2020. We comparatively analyzed the infection rate and outcome between patients using cefoperazone-sulbactam or piperacillin-tazobactam and those using carbapenems as surgical prophylaxis.

Results

This study included 105 LT recipients. Seventy-eight and 27 patients used non-carbapenem and carbapenem antibiotics, respectively, as surgical prophylaxis. The corresponding infection incidence rates within 30 days were 38.5% and 66.7% (p = 0.011). Multivariate analysis revealed that reoperation and the Child–Pugh score were independent risk factors for infections within 30 days after LT. The following four risk factors were associated with the 180-day post-LT survival: MELD score, vascular complication, intra-abdominal bleeding, and infection with carbapenem-resistant organisms (CROs). There was no significant difference in CRO infection incidence between the carbapenem and non-carbapenem groups (18.5% vs 11.5%; p = 0.345).

Conclusion

Carbapenem use as surgical prophylaxis was not associated with infection incidence within 30 days after LT, 180-day post-LT survival or CRO infection. Therefore, carbapenems are not superior to cephalosporin or piperacillin-tazobactam for perioperative antibiotic prophylaxis in LT recipients with a MELD score ≥30.

Surgical Site Infections in Post-Living Donor Liver Transplantation: Surveillance and Evaluation of Care Bundle Approach

Background and Aim: Although implantation of a care bundle approach is well established in intensive care units (ICUs), yet its impact on reducing surgical site infections (SSI) among post living-donor-liver transplantation (LDLT) patients has not been established. Our aim is to evaluate the impact of a care bundle in reducing SSI and to detect the pattern of antibiotic resistance in LDLT. Materials and Methods: This before and after comparative study was conducted at Elmanial specialized tertiary hospital, Cairo University over a period of 3 years (January 2016 - December 2018) including 57 LDLT patients. We introduced a care bundle comprised of a group of evidence-based practices implemented together. The study was divided into three phases. All bacterial identification and antibiotic sensitivity testing were done by a Vitek 2 compact system. Results: SSIs rates were reduced significantly by 30.4% from the pre-implementation to the post implementation phase (from 13/24, 54.2% to 5/21, 23.8%, OR 0.21, CI 95%: 1.137- 0.039). This reduction went hand in hand with increase in the hand hygiene compliance from 57.3 % to 78 %, then remained sustained with a median rate of 78% in the last 6 months. Klebsiella pneumoniae 11\25 (44% of SSIs), Acinetobacter baumannii 8\25 (32% of SSIs), Escherichia coli 5\25 (20%), Pseudomonas aeruginosa 5\25 (20%) and MRSA 4\25 (16%). With predominance of XDR phenotype 14/25 (56%), followed by ESBL of gram-negative bacteria 6/25 (24%), then MRSA 4/25 (16%). Conclusion: SSIs in LDLT mandates strict implementation of comprehensive evidence-based care bundles for better patent outcome.

Analysis of risk factors for impaired wound healing after kidney transplantation

To analyse risk factors for impaired wound healing after kidney transplantation to guide clinical decision-making. A retrospective analysis was performed on patients who received kidney transplantation from January 1, 2019, to May 1, 2021, at Kidney Transplantation Center in Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine. A case-control study was used to identify a cohort of patients with similar baseline characteristics according to 1:4 ratio. Patients were divided into two groups according to whether there was impaired wound healing after surgery. The basic data and clinical examinations between the two groups were compared, and the risk factors for impaired wound healing after kidney transplantation were analysed using univariate and multivariate analyses. According to the data type, independent samples t-test or Chi-squared test was used for comparison between groups. Furthermore, multivariate logistic regression analysis was used to analyse different risk factors and calculate the odds ratio (OR) and 95% confidence interval (CI) of each factor. A total of 18 patients showed impaired wound healing after kidney transplantation. And we conducted 72 statically matched controls. Age, diabetes, transplant types, body mass index (BMI), albumin, haemoglobin, and wound infection were statistically different between the two groups. The factors with statistically significant differences in univariate analysis were included in multivariate logistic regression analysis. The results showed that BMI > 25, fasting blood glucose level, albumin level, and prealbumin level were independent risk factors for impaired wound healing after kidney transplantation. Risk factors for impaired wound healing after kidney transplantation can be detected after surgery. Strengthening postoperative monitoring and early intervention of recipients with such factors may effectively prevent impaired wound healing after kidney transplantation.

Therapeutic evaluation of immunomodulators in reducing surgical wound infection

Despite many advances in infection control practices, including prophylactic antibiotics, surgical site infections (SSIs) remain a significant cause of morbidity, prolonged hospitalization, and death worldwide. Our innate immune system possesses a multitude of powerful antimicrobial strategies which make it highly effective in combating bacterial, fungal, and viral infections. However, pathogens use various stealth mechanisms to avoid the innate immune system, which in turn buy them time to colonize wounds and damage tissues at surgical sites. We hypothesized that immunomodulators that can jumpstart and activate innate immune responses at surgical sites, would likely reduce infection at surgical sites. We used three immunomodulators; fMLP (formyl-Methionine-Lysine-Proline), CCL3 (MIP-1α), and LPS (Lipopolysaccharide), based on their documented ability to elicit strong inflammatory responses; in a surgical wound infection model with Pseudomonas aeruginosa to evaluate our hypothesis. Our data indicate that one-time topical treatment with these immunomodulators at low doses significantly increased proinflammatory responses in infected and uninfected surgical wounds and were as effective, (or even better), than a potent prophylactic antibiotic (Tobramycin) in reducing P. aeruginosa infection in wounds. Our data further show that immunomodulators did not have adverse effects on tissue repair and wound healing processes. Rather, they enhanced healing in both infected and uninfected wounds. Collectively, our data demonstrate that harnessing the power of the innate immune system by immunomodulators can significantly boost infection control and potentially stimulate healing. We propose that topical treatment with these immunomodulators at the time of surgery may have therapeutic potential in combating SSI, alone or in combination with prophylactic antibiotics.

[Perioperative management of the brain-dead organ donor : Anesthesia between ethics and evidence]

Hintergrund

Die Anzahl postmortal gespendeter Organe ist in Deutschland weit geringer als der Bedarf. Dies unterstreicht die Wichtigkeit einer optimalen Versorgung während des gesamten Prozesses der Organspende.

Fragestellung

Es existieren internationale Leitlinien und nationale Empfehlungen zu intensivmedizinischen organprotektiven Maßnahmen beim Organspender. Für das anästhesiologische Management fehlen evidenzbasierte Empfehlungen. Ziel dieser Übersichtsarbeit ist es, anhand der vorhandenen Evidenz die pathophysiologischen Veränderungen des irreversiblen Hirnfunktionsausfalls zu rekapitulieren und sich kritisch mit den empfohlenen Behandlungsstrategien und therapeutischen Zielgrößen auseinanderzusetzen. Auch auf ethische Aspekte der Betreuung des postmortalen Organspenders wird eingegangen.

Methode

Diese Übersichtsarbeit basiert auf einer selektiven Literaturrecherche in PubMed (Suchwörter: „brain dead donor“, „organ procurement“, „organ protective therapy“, „donor preconditioning“, „perioperative donor management“, „ethical considerations of brain dead donor“). Internationale Leitlinien und nationale Empfehlungen wurden besonders berücksichtigt.

Ergebnisse

Insgesamt ist die Evidenz für optimale intensivmedizinische und perioperative organprotektive Maßnahmen beim postmortalen Organspender sehr gering. Nationale und internationale Empfehlungen zu Zielwerten und medikamentösen Behandlungsstrategien unterscheiden sich teilweise erheblich: kontrollierte randomisierte Studien fehlen. Der Stellenwert einer Narkose zur Explantation bleibt sowohl unter pathophysiologischen Gesichtspunkten als auch aus ethischer Sicht ungeklärt.

Schlussfolgerungen

Die Kenntnisse über die pathophysiologischen Prozesse im Rahmen des irreversiblen Hirnfunktionsausfalls und die organprotektiven Maßnahmen sind ebenso Grundvoraussetzung wie die ethische Auseinandersetzung mit dem Thema postmortale Organspende. Nur dann kann das Behandlungsteam in dieser herausfordernden Situation sowohl dem Organempfänger als auch dem Organspender und seinen Angehörigen gerecht werden.

Bacterial infections in lung transplantation

Lung transplantation has lower survival rates compared to other than other solid organ transplants (SOT) due to higher rates of infection and rejection-related complications, and bacterial infections (BI) are the most frequent infectious complications. Excess morbidity and mortality are not only a direct consequence of these BI, but so are subsequent loss of allograft tolerance, rejection, and chronic lung allograft dysfunction due to bronchiolitis obliterans syndrome (BOS). A wide variety of pathogens can cause infections in lung transplant recipients (LTRs), including a number of nosocomial pathogens and other multidrug-resistant (MDR) pathogens. Although pneumonia and intrathoracic infections predominate, LTRs are at risk of a number of types of infections. Risk factors include altered anatomy and function of airways, impaired immunity, the microbial flora of the donor and recipient, underlying medical conditions, and genetic factors. Further work on immune monitoring has the potential to improve outcomes. The infecting agents can be derived from the donor lung, pre-existing recipient flora, or acquired from the environment over time. Certain infections may preclude lung transplantation, but this varies from center to center, and more recent studies suggest fewer patients should be disqualified. New molecular methods allow microbiome studies of the lung, gut, and other sites that may further our knowledge of how airway colonization can result in infection and allograft loss. Surveillance, early diagnosis, and aggressive antimicrobial therapy of BI is critical in LTRs. Antibiotic resistance is a major barrier to successful management of these infections. The availability of new agents for MDR Gram-negatives may improve outcomes. Other new therapies, such as bacteriophage therapy, show promise for the future. Finally, it is important to prevent infections through peri-transplant prophylaxis, vaccination, and infection control measures.

First World Consensus Conference on pancreas transplantation: Part II - recommendations

The First World Consensus Conference on Pancreas Transplantation provided 49 jury deliberations regarding the impact of pancreas transplantation on the treatment of diabetic patients, and 110 experts' recommendations for the practice of pancreas transplantation. The main message from this consensus conference is that both simultaneous pancreas-kidney transplantation (SPK) and pancreas transplantation alone can improve long-term patient survival, and all types of pancreas transplantation dramatically improve the quality of life of recipients. Pancreas transplantation may also improve the course of chronic complications of diabetes, depending on their severity. Therefore, the advantages of pancreas transplantation appear to clearly surpass potential disadvantages. Pancreas after kidney transplantation increases the risk of mortality only in the early period after transplantation, but is associated with improved life expectancy thereafter. Additionally, preemptive SPK, when compared to SPK performed in patients undergoing dialysis, appears to be associated with improved outcomes. Time on dialysis has negative prognostic implications in SPK recipients. Increased long-term survival, improvement in the course of diabetic complications, and amelioration of quality of life justify preferential allocation of kidney grafts to SPK recipients. Audience discussions and live voting are available online at the following URL address: http://mediaeventi.unipi.it/category/1st-world-consensus-conference-of-pancreas-transplantation/246.

Antibiotic prophylaxis in patients with cirrhosis: Current evidence for clinical practice

Patients with cirrhosis show an increased susceptibility to infection due to disease-related immune-dysfunction. Bacterial infection therefore represents a common, often detrimental event in patients with advanced liver disease, since it can worsen portal hypertension and impair the function of hepatic and extra-hepatic organs. Among pharmacological strategies to prevent infection, antibiotic prophylaxis remains the first-choice, especially in high-risk groups, such as patients with acute variceal bleeding, low ascitic fluid proteins, and prior episodes of spontaneous bacterial peritonitis. Nevertheless, antibiotic prophylaxis has to deal with the changing bacterial epidemiology in cirrhosis, with increased rates of gram-positive bacteria and multidrug resistant rods, warnings about quinolones-related side effects, and low prescription adherence. Short-term antibiotic prophylaxis is applied in many other settings during hospitalization, such as before interventional or surgical procedures, but often without knowledge of local bacterial epidemiology and without strict adherence to antimicrobial stewardship. This paper offers a detailed overview on the application of antibiotic prophylaxis in cirrhosis, according to the current evidence.

Therapeutic assessment of N-formyl-methionyl-leucyl-phenylalanine (fMLP) in reducing periprosthetic joint infection

Despite many preventive measures, including prophylactic antibiotics, periprosthetic joint infection (PJI) remains a devastating complication following arthroplasty, leading to pain, suffering, morbidity and substantial economic burden. Humans have a powerful innate immune system that can effectively control infections, if alerted quickly. Unfortunately, pathogens use many mechanisms to dampen innate immune responses. The study hypothesis was that immunomodulators that can jumpstart and direct innate immune responses (particularly neutrophils) at the surgical site of implant placement would boost immune responses and reduce PJI, even in the absence of antibiotics. To test this hypothesis, N-formyl-methionyl-leucyl-phenylalanine (fMLP) (a potent chemoattractant for phagocytic leukocytes including neutrophils) was used in a mouse model of PJI with Staphylococcus aureus (S. aureus). Mice receiving intramedullary femoral implants were divided into three groups: i) implant alone; ii) implant + S. aureus; iii) implant + fMLP + S. aureus. fMLP treatment reduced S. aureus infection levels by ~ 2-Log orders at day 3. Moreover, fMLP therapy reduced infection-induced peri-implant periosteal reaction, focal cortical loss and areas of inflammatory infiltrate in mice distal femora at day 10. Finally, fMLP treatment reduced pain behaviour and increased weight-bearing at the implant leg in infected mice at day 10. Data indicated that fMLP therapy is a promising novel approach for reducing PJI, if administered locally at surgical sites. Future work will be toward further enhancement and optimisation of an fMLP-based therapeutic approach through combination with antibiotics and/or implant coating with fMLP.

Surgical site infection prevention and management in immunocompromised patients: a systematic review of the literature

BACKGROUND

Immunocompromised patients are at higher risk of surgical site infection and wound complications. However, optimal management in the perioperative period is not well established. Present systematic review aims to analyse existing strategies and interventions to prevent and manage surgical site infections and other wound complications in immunocompromised patients.

METHODS

A systematic review of the literature was conducted.

RESULTS

Literature review shows that partial skin closure is effective to reduce SSI in this population. There is not sufficient evidence to definitively suggest in favour of prophylactic negative pressure wound therapy. The use of mammalian target of rapamycin (mTOR) and calcineurin inhibitors (CNI) in transplanted patient needing ad emergent or undeferrable abdominal surgical procedure must be carefully and multidisciplinary evaluated. The role of antibiotic prophylaxis in transplanted patients needs to be assessed.

CONCLUSION

Strict adherence to SSI infection preventing bundles must be implemented worldwide especially in immunocompromised patients. Lastly, it is necessary to elaborate a more widely approved definition of immunocompromised state. Without such shared definition, it will be hard to elaborate the needed methodologically correct studies for this fragile population.

Working towards an ERAS Protocol for Pancreatic Transplantation: A Narrative Review

Enhanced recovery after surgery (ERAS) initially started in the early 2000s as a series of protocols to improve the perioperative care of surgical patients. They aimed to increase patient satisfaction while reducing postoperative complications and postoperative length of stay. Despite these protocols being widely adopted in many fields of surgery, they are yet to be adopted in pancreatic transplantation: a high-risk surgery with often prolonged length of postoperative stay and high rate of complications. We have analysed the literature in pancreatic and transplantation surgery to identify the necessary preoperative, intra-operative and postoperative components of an ERAS pathway in pancreas transplantation.

Late complications of pancreas transplant

To summarize the long-term complications after pancreas transplantation that affect graft function, a literature search was carried out on the long-term complications of pancreatic transplantation, namely, complications from postoperative 3^rd mo onwards, in terms of loss of graft function, late infection and vascular complications as pseudoaneurysms. The most relevant reviews and studies were selected to obtain the current evidence on these topics. The definition of graft failure varies among different studies, so it is difficult to evaluate, a standardized definition is of utmost importance to know the magnitude of the problem in all worldwide series. Chronic rejection is the main cause of long-term graft failure, occurring in 10% of patients. From the 3rd mo of transplantation onwards, the main risk factor for late infections is immunosuppression, and patients have opportunistic infections like: Cytomegalovirus, hepatitis B and C viruses, Epstein-Barr virus and varicella-zoster virus; opportunistic bacteria, reactivation of latent infections as tuberculosis or fungal infections. Complete preoperative studies and serological tests should be made in all recipients to avoid these infections, adding perioperative prophylactic treatments when indicated. Pseudoaneurysm are uncommon, but one of the main causes of late bleeding, which can be fatal. The treatment should be performed with radiological endovascular approaches or open surgery in case of failure. Despite all therapeutic options for the complications mentioned above, transplantectomy is a necessary option in approximately 50% of relaparotomies, especially in life-threatening complications. Late complications in pancreatic transplantation threatens long-term graft function. An exhaustive follow-up as well as a correct immunosuppression protocol are necessary for prevention.

Effectiveness of short vs long-course perioperative antibiotics in lung transplant recipients with donor positive respiratory cultures

Lung transplant recipients are at increased risk for infection in the early postoperative phase, thus perioperative antibiotics are employed. This retrospective study evaluated the efficacy of short- vs long-course perioperative antibiotics in lung transplant patients. Lung transplant patients with donor positive cultures between August 2013 and September 2019 were evaluated, excluding those with cystic fibrosis, death within 14 days and re-transplants. The primary outcome was 30-day freedom from donor-derived respiratory infection. A total of 147 patients were included (57 short vs 90 long-course). Median perioperative antibiotic duration was 6 days in the short-course vs 14 days in the long-course group (P < .0001). Thirty-day freedom from donor-derived respiratory infection was present in 56 (98%) patients in the short-course vs 85 (94%) patients in the long-course group (P = .41). There was no difference in development of Clostridioides difficile infections (P = .41), while cumulative ventilator time and time to post-op extubation were longer in the long-course group (P = .001 and .004, respectively). Among lung transplant recipients with positive donor respiratory cultures, short-course perioperative antibiotics were as effective as long-course antibiotics in preventing donor-derived bacterial respiratory infections.

The economic impact of increased length of stay associated with surgical site infections in liver transplantation on Canadian healthcare costs

BACKGROUND

Complications after liver transplantation cause additional healthcare costs. The objective of this study was to contrast the length of stay (LOS) costs for recipients with and without surgical site infections (SSIs).

METHODS

This retrospective observational cohort study was conducted at a transplant center in Canada, between February 2011 and August 2014. The difference in the LOS costs was assessed by the Mann-Whitney U test, while multiple linear regression analysis was used to identify the variables that may have impacted on the costs.

RESULTS

Two hundred and twenty-nine liver transplant recipients were enrolled. Thirty-six recipients developed SSIs (36/229, 15.7%). The median LOS costs in recipients with and without SSIs were $39,456 Canadian dollars (interquartile range $25,696- 59,722) and $31,084 Canadian dollars (interquartile range $22,712-49 610), respectively (p = .072). There was a trend that the costs were higher for those recipients with versus those without SSIs (p = .088). Transfusion of ≥ 5 units of red cells and dialysis before transplantation impacted on cost.

CONCLUSION

There was a trend for higher healthcare facility costs for recipients with SSIs. Red cell transfusions and greater dialysis use before transplant were factors associated with the cost. Implementation of cost reduction strategies targeting high-cost recipients is necessary.

Perioperative antibiotics for preventing post-surgical site infections in solid organ transplant recipients

BACKGROUND

Solid organ transplant recipients are at high risk for infections due to the complexity of surgical procedures combined with the impact of immunosuppression. No consensus exists on the role of antibiotics for surgical site infections in solid organ transplant recipients.

OBJECTIVES

To assess the benefits and harms of prophylactic antimicrobial agents for preventing surgical site infections in solid organ transplant recipients.

SEARCH METHODS

The Cochrane Kidney and Transplant Register of Studies was searched up to 21 April 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs in any language assessing prophylactic antibiotics in preventing surgical site infections in solid organ transplant recipients at any time point after transplantation.

DATA COLLECTION AND ANALYSIS

Two authors independently determined study eligibility, assessed quality, and extracted data. Primary outcomes were surgical site infections and antimicrobial resistance. Other outcomes included urinary tract infections, pneumonias and septicaemia, death (any cause), graft loss, graft rejection, graft function, adverse reactions to antimicrobial agents, and outcomes identified by the Standardised Outcomes of Nephrology Group (SONG), specifically graft health, cardiovascular disease, cancer and life participation. Summary effect estimates were obtained using a random-effects model and results were expressed as risk ratios (RR) and 95% confidence intervals (CI). The quality of the evidence was assessed using the risk of bias and the GRADE approach.

MAIN RESULTS

We identified eight eligible studies (718 randomised participants). Overall, five studies (248 randomised participants) compared antibiotics versus no antibiotics, and three studies (470 randomised participants) compared extended duration versus short duration antibiotics. Risk of bias was assessed as high for performance bias (eight studies), detection bias (eight studies) and attrition bias (two studies). It is uncertain whether antibiotics reduce the incidence of surgical site infections as the certainty of the evidence has been assessed as very low (RR 0.42, 95% CI 0.21 to 0.85; 5 studies, 226 participants; I² = 25%). The certainty of the evidence was very low for all other reported outcomes (death, graft loss, and other infections). It is uncertain whether extended duration antibiotics reduces the incidence of surgical site infections in either solid organ transplant recipients (RR 1.19, 95% CI 0.58 to 2.48; 2 studies, 302 participants; I² = 0%) or kidney-only transplant recipients (RR 0.50, 95% CI 0.05 to 5.48; 1 study, 205 participants) as the certainty of the evidence has been assessed as very low. The certainty of the evidence was very low for all other reported outcomes (death, graft loss, and other infections). None of the eight included studies evaluated antimicrobial agent adverse reactions, graft health, cardiovascular disease, cancer, life participation, biochemical and haematological parameters, intervention cost, hospitalisation length, or overall hospitalisation costs.

AUTHORS' CONCLUSIONS

Due to methodological limitations, risk of bias and significant heterogeneity, the current evidence for the use of prophylactic perioperative antibiotics in transplantation is of very low quality. Further high quality, adequately powered RCTs would help better inform clinical practice.

Duration of Perioperative Antimicrobial Prophylaxis in Orthotopic Liver Transplantation Patients

INTRODUCTION

According to clinical guidelines, there are no differences in early infection rates when utilizing antimicrobial prophylaxis regimens beyond 24 hours. We shortened the prophylaxis regimen from 72 to 24 hours in liver transplant recipients due to rising rates of resistance. The objective of this study is to evaluate the difference in posttransplant outcomes, following the protocol change.

DESIGN

We reviewed adult patients undergoing orthotopic liver transplantation between June 2013 and December 2015. Patients were stratified into 2 cohorts: 24 and 72 hours. Patients were excluded if donor cultures were positive. The primary objective of this study is to evaluate the incidence and time to posttransplant infections. The secondary objectives included analysis of total and intensive care unit length of stay and rates of Clostridioides difficile infection.

RESULTS

Forty-four patients were included, 20 in the 72-hour and 24 in the 24-hour cohorts. The incidence of post-OLT infection (30% vs 8%, P = .115, 95% CI: -1% to 45%) was higher in the 72-hour cohort. Total (21 vs 14, P = .332, 95% CI: -4% to 28%) and intensive care unit LOS (11 vs 6, P = .201, 95% CI, -5% to 31%) were longer in the 72-hour group. No difference was observed in the incidence of CDI (15% vs 13%, P = 1.000).

DISCUSSION

There was no increase in posttransplant infections in the 24-hour cohort. Shorter antibiotic exposure may be associated with a reduction in length of stay and be favorable in this patient population.

Correlation of intraoperative donor duodenal-segment swab cultures with the subsequent occurrence of surgical site infections in kidney and pancreas transplant recipients

BACKGROUND

Pancreas transplantation is employed for the treatment of type I diabetes mellitus. It is postulated that surgical site infection (SSI), particularly organ-space infections, after pancreas transplantation may arise from microbial contamination arising from the donor duodenal segment. Therefore, some centers have adopted the practice of culturing the donor duodenal segment and subsequently administering antimicrobial therapy to the recipient directed at the microorganisms isolated to prevent SSI.

METHODS

In this retrospective cohort study, we evaluated the correlation between positive donor duodenal-segment cultures and SSIs in the recipients. Data were recorded and analyzed to assess the correlation of the organisms isolated in the donor duodenal cultures with those producing SSI in the recipients.

RESULTS

We evaluated 379 consecutive pancreas transplant recipients from January 2000 to December 2015. Donor duodenal swab cultures were performed at the time of pancreas transplantation, and 206 (54.3%) were positive. SSIs occurred in 51 of the 206 recipients (24.8%) with positive duodenal-segment cultures and in 41 of 173 individuals (23.7%) with negative cultures (P = .81; r = 0.00). Notably, deep and organ-space SSIs were observed in 27 of 206 of the positive duodenal culture groups (13.1%) versus 29 of 173 of the negative duodenal culture groups (16.8%; P = 0.31; r = -0.059). No differences were detected in the pathogens producing SSIs between the group with a positive duodenal swab versus the group with a negative swab. Microorganisms producing SSIs matched those found in the positive donor duodenal cultures in only 15 patients (7.8%).

CONCLUSION

Although positive cultures from the donor duodenal segment prompted the administration of antimicrobial therapy in the recipient directed against the pathogen isolated, this practice did not reduce SSIs compared with those transplant recipients with culture-negative duodenal swabs. In addition, the organisms isolated from the donor duodenal segment were not predictive of subsequent SSI.

Controversies in Perioperative Antimicrobial Prophylaxis

Although clinical guidelines for antibiotic prophylaxis across a wide array of surgical procedures have been proposed by multidisciplinary groups of physicians and pharmacists, clinicians often deviate from recommendations. This is particularly true when recommendations are based on weak data or expert opinion. The goal of this review is to highlight certain common but controversial topics in perioperative prophylaxis and to focus on the data that does exist for the recommendations being made.

Antimicrobial stewardship in transplant patients

PURPOSE OF REVIEW

To provide an update on the current landscape of antimicrobial stewardship in solid organ transplant (SOT) recipients.

RECENT FINDINGS

Constructing personalized antimicrobial prescribing approaches to avoid untoward consequences of antimicrobials while improving outcomes is an emerging and critical aspect of transplant medicine. Stewardship activities encompassing the specialized interests of transplant patients and programs are evolving. New literature evaluating strategies to optimize antimicrobial agent selection, dosing, and duration have been published. Additionally, consensus guidance for certain infectious clinical syndromes is available and should inform institutional clinical practice guidelines. Novel metrics for stewardship-related outcomes in transplantation are desperately needed. Though exciting new molecular diagnostic technologies will likely be pivotal in the care of immunocompromised patients, optimal clinical adaptation and appropriate integration remains unclear. Important studies understanding the behaviors influencing antimicrobial prescribing in organizational transplant cultures are needed to optimize interventions.

SUMMARY

Consequences of antimicrobial use, such as Clostridiodes difficile and infections with multidrug-resistant organisms disproportionately affect SOT recipients and are associated with poor allograft and patient outcomes. Application of ASP interventions tailored to SOT recipients is recommended though further studies are needed to provide guidance for best practice.

Bacterial infections in the early period after liver transplantation in adults: A prospective single-center cohort study

Liver transplantation (LT) is a potentially curative treatment for terminal stage hepatic diseases. Bacterial infections are the main causes of mortality and morbidity in the early period after LT. Identifying the risk factors could help in minimizing their development. We prospectively investigated the incidence, characteristics, and risk factors of bacterial infections among the recipients during hospitalization after LT and assigned a predictive score. All 389 consecutive adults who underwent LT at the main referral hospital of LT in Iran during 1 year were enrolled prospectively in a cohort study. Infection group consisted of 143 recipients (36.8%). Urinary tract and surgical site infections were the most frequent ones. Gram-negative bacteria were more prevalent than Gram-positive ones. Independent risk factors were female sex (relative risks = 2.13), age ≤ 43.5 years (3.70), hospital stay ≥ 9.5 days (5.22), abdominal reoperation (3.03), vancomycin-resistant Enterococci colonization (5.52), hospitalization 3 months prior to LT (3.25), mechanical ventilation ≥48 hr (4.93), and renal replacement therapies (13.40). We developed a risk score for the prediction of bacterial infections with an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.81-0.89) with sensitivity of 88% and specificity of 64%. In the infection group, mortality was higher than in controls (18.9% vs. 2.0%) with longer hospitalization (16 vs. 10 days; P < 0.001). We detected a high rate of bacterial infections leading to longer hospital stay and higher mortality rate. The formulated risk score can help predict bacterial infections; however, it requires clinical validation in further studies.

Management and prophylaxis of bacterial and mycobacterial infections among lung transplant recipients

Bacterial and mycobacterial infections are associated with morbidity and mortality in lung transplant recipients. Infectious complications are categorized by timing post-transplant: <1, 1–6, and >6 months. The first month post-transplant is associated with the highest risk of infection. During this period, infections are most commonly healthcare-associated, and include infections related to surgical complications. The lungs and bloodstream are common sites of infections. Common healthcare-associated organisms include methicillin-resistant Staphylococcus aureus (MRSA), Gram-negative bacilli such as Pseudomonas aeruginosa, and Clostridioides difficile. More than 1-month post-transplant, opportunistic infections can occur. Tuberculosis occurs in 0.8–10% of lung transplant recipients which reflects variation in background prevalence. The majority of post-transplant tuberculosis stems from reactivation of untreated or undiagnosed latent tuberculosis. Most post-transplant tuberculosis occurs in the lungs and develops within a year of transplant. Non-tuberculous mycobacteria commonly colonize the lungs of lung transplant candidates and are often hard to eradicate even with prolonged courses of antimycobacterial agents. Drug interactions between antimycobacterial agents and calcineurin and mTOR inhibitors also complicates treatment post-transplant. Given that infection adversely impacts outcomes after lung transplant, and that anti-infective therapy is often less effective after transplant, infection prevention is key to long-term success. A comprehensive approach that includes pre-transplant evaluation, perioperative prophylaxis, long-term antimicrobial prophylaxis, immunization, and safer living at home and in the community, should be employed to minimize the risk of infection.

Methicillin-resistant Staphylococcus aureus carriers are vulnerable to bloodstream infection after living donor liver transplantation

BACKGROUND

Bloodstream infection (BSI) is a life-threatening complication after living donor liver transplantation (LDLT). We aimed to explore the incidence and predisposing factors of BSI at our institution.

METHODS

We conducted a retrospective cohort analysis on all consecutive adults with BSI within 6 months after LDLT performed between 2005 and 2016. For antimicrobial prophylaxis, ampicillin/sulbactam, cefotaxime, and micafungin were administered. From 2011, methicillin-resistant Staphylococcus aureus (MRSA) carriers were decolonized using mupirocin ointment and chlorhexidine gluconate soap. Risk factors for BSI were identified by uni- and multivariate logistic regression.

RESULTS

Of a total of 106 LDLTs, 42 recipients (40%) suffered BSI. The BSI group demonstrated significantly higher in-hospital mortality rates compared with the non-BSI group (24% vs. 7%, P = .01). We identified MRSA carrier (odds ratio [OR], 19.1; P < .001), ABO incompatibility (OR, 2.9; P = .03), and estimated glomerular filtration rate <30 mL/min/1.73m² (OR, 15.8; P = .02) as independent risk factors for BSI. Decolonization treatment for MRSA carriers did not reduce the incidence of all-cause BSI but reduced the frequency of BSI caused by MRSA.

CONCLUSION

To our knowledge, for the first time, MRSA carriers were revealed to be highly vulnerable to BSI after LDLT.

Esophagectomy for the patients with squamous cell carcinoma of the esophagus after allogeneic hematopoietic stem cell transplantation

BACKGROUND

The number of long-term survivors after allogeneic hematopoietic stem cell transplantation (HSCT) has increased recently. Esophageal squamous cell carcinoma occurs at a particularly high incidence as a secondary cancer after HSCT. However, standard treatment for these patients has not been established yet. The objectives of this study were to investigate outcomes of esophagectomy for esophageal carcinoma developed in HSCT patients, and to provide the appropriate perioperative management.

METHODS

Ten HSCT patients underwent esophagectomy for esophageal squamous cell carcinoma between December 2007 and September 2017 at the National Cancer Center Hospital. The surgical outcomes and long-term prognosis of these patients were reviewed retrospectively.

RESULTS

In the former group, 5 of the 7 patients (71.4%) developed pneumonia after esophagectomy, with two of them requiring intubation because of respiratory failure. None of the three patients of the latter group, who received broad-spectrum antibiotics for more than 7 days after the surgery, developed any postoperative complications. The estimated survival probability of these patients at 5 years after the surgery was 53.3%.

CONCLUSIONS

HSCT patients have an extremely high risk of developing pneumonia after esophagectomy, and the condition can easily become serious. Therefore, broad-spectrum antibiotics should be administered prophylactically to prevent severe pneumonia during the perioperative period in these patients.

Nanosystems as Vehicles for the Delivery of Antimicrobial Peptides (AMPs)

Recently, antimicrobial peptides (AMPs), also called host defence peptides (HDPs), are attracting great interest, as they are a highly viable alternative in the search of new approaches to the resistance presented by bacteria against antibiotics in infectious diseases. However, due to their nature, they present a series of disadvantages such as low bioavailability, easy degradability by proteases, or low solubility, among others, which limits their use as antimicrobial agents. For all these reasons, the use of vehicles for the delivery of AMPs, such as polymers, nanoparticles, micelles, carbon nanotubes, dendrimers, and other types of systems, allows the use of AMPs as a real alternative to treatment with antibiotics.

Risk factors for multidrug-resistant organisms among deceased organ donors

Donor infection or colonization with a multidrug-resistant organism (MDRO) affects organ utilization and recipient antibiotic management. Approaches to identifying donors at risk of carrying MDROs are unknown. We sought to determine the risk factors for MDROs among transplant donors. A multicenter retrospective cohort study was conducted at four transplant centers between 2015 and 2016. All deceased donors who donated at least one organ were included. Cultures obtained during the donor's terminal hospitalization and organ procurement were evaluated. The primary outcome was isolation of an MDRO on culture. Multivariable Cox regression was used to determine risk factors associated with time to donor MDRO. Of 440 total donors, 64 (15%) donors grew an MDRO on culture. Predictors of an MDRO on donor culture included hepatitis C viremia (hazard ratio [HR] 4.09, 95% confidence interval [CI] 1.71-9.78, P = .002), need for dialysis (HR 4.59, 95% CI 1.09-19.21, P = .037), prior hematopoietic cell transplant (HR 7.57, 95% CI 1.03-55.75, P = .047), and exposure to antibiotics with a narrow gram-negative spectrum (HR 1.13, 95% CI 1.00-1.27, P = .045). This is the first study to determine risk factors for MDROs among deceased donors and will be important for risk stratifying potential donors and informing transplant recipient prophylaxis.

Reoperation in Early Kidney Post-transplant Period as a Strong Risk Factor of Surgical Site Infection Occurrence

BACKGROUND

One of the most common infective complications after kidney transplant (KTx) is surgical site infection (SSI). Providing indications of improvement of perioperative antibiotic prophylaxis (PAP) and allowing the characterization of risk factors are critical to reduce SSI. The purpose of this study was to evaluate the SSI risk factors and impact of reoperation in the early post-transplant period on SSI occurrence and assess if standard PAP in those cases is a best consideration.

METHODS

Between April 2014 and October 2015, a total of 236 KTxs were performed in our center. Deceased donor data, recipient data, and data related to surgical procedures were collected.

RESULTS

Surgical site infections were reported in 5.6% (12/214) of patients. Seven patients were diagnosed as having superficial SSI (7/12; 58.3%), 2 with deep SSI (2/12; 16.6%), and 4 with organ-specific SSI (4/12; 33.3%). Extended criteria donor-related transplant, cold ischemia time > 22 hours, dialysis period > 30 months, recipient age older than 45 years, recipient body mass index > 27, induction therapy prior to transplant, diabetes prior to transplant, and ≥ 1 reoperation during 30 days of observation were independent risk factors of SSI occurrence. A total of 19 reoperations were performed in 17 patients. In 8 of all 12 patients with SSI diagnosis, the reoperation was performed (66.7%). In 202 patients of non-SSI patients, only 9 reoperations were performed (4.5%).

CONCLUSIONS

Early reoperation after Ktx is a strong risk factor of SSI occurrence. There is a probability that > 4 SSI risk factors and reoperation in the early post-transplant period could require different and more aggressive proceeding, as standard PAP in those cases is insufficient.

Single mutidrug resistant enterobacteriacae donor-derived infection in four solid organ transplant recipients: a case report

Background

Bacteraemia of the donor is not considered to be contraindication of organ procurement. On the other hand, infection of solid organ transplant recipients remains to be a major cause of their morbidity and mortality. When using organs from bacteraemic donors, individual risks need to be assessed and the appropriate antibiotic treatment applied.

Case presentation

In this case series we report several serious donor–derived infectious complications in four out of five recipients of different organs from one single donor in the early posttransplant period. Donor-transmitted multi-drug resistant strains of Escherichia coli and Klebsiella pneumonia was confirmed by both serologic and molecular testing.

Conclusions

To prevent donor-derived infections, careful microbiological screening followed by targeted antibiotic treatment is essential. Although such complications can never by completely prevented, a high index for potential bacterial infection in organ donors and transplant recipients should be routinely employed.

Intraoperative Versus Extended Antibiotic Prophylaxis in Liver Transplant Surgery: A Randomized Controlled Pilot Trial

The appropriate duration of surgical antibiotic prophylaxis in orthotopic liver transplantation (OLT) in the presence of significant iatrogenic immunosuppression is unclear. We hypothesized that 72 hours of perioperative antibiotic prophylaxis would decrease rates of surgical site infection (SSI) in OLT patients when compared with intraoperative antibiotic prophylaxis alone. OLT recipients were randomized to receive either intraoperative antibiotics only (short antibiotics [SAs]) or 72 hours of perioperative antibiotics (extended antibiotics [EAs]). A total of 102 patients were randomized: 51 to the EA group and 51 to the SA group. Rates of SSI and nosocomial infection (NI) in the SA group were 19% and 17%, respectively, compared with 27% (SSI; P = 0.36) and 22% (NI; P = 0.47) in the EA group, although these differences were not statistically significant. Intensive care unit (ICU) length of stay (LOS), hospital LOS, 30-day mortality, and time to infection were also similar between the 2 groups. Patients developing infections had longer ICU LOS and hospital LOS and a higher association with reoperation, endoscopic retrograde cholangiopancreatography, and 30-day readmission. In conclusion, extending perioperative antibiotics to 72 hours from intraoperative dosing alone in OLT patients does not appear to decrease the incidence of SSI or NI. The results from this pilot trial with 60% power suggest that it is acceptable for OLT recipients to receive intraoperative antibiotic prophylaxis alone.