Infections in liver transplant recipients

Effect of Cellular Senescence in Disease Progression and Transplantation: Immune Cells and Solid Organs

Aging of the world population significantly impacts healthcare globally and specifically, the field of transplantation. Together with end-organ dysfunction and prolonged immunosuppression, age increases the frequency of comorbid chronic diseases in transplant candidates and recipients, contributing to inferior outcomes. Although the frequency of death increases with age, limited use of organs from older deceased donors reflects the concerns about organ durability and inadequate function. Cellular senescence (CS) is a hallmark of aging, which occurs in response to a myriad of cellular stressors, leading to activation of signaling cascades that stably arrest cell cycle progression to prevent tumorigenesis. In aging and chronic conditions, senescent cells accumulate as the immune system's ability to clear them wanes, which is causally implicated in the progression of chronic diseases, immune dysfunction, organ damage, decreased regenerative capacity, and aging itself. The intimate interplay between senescent cells, their proinflammatory secretome, and immune cells results in a positive feedback loop, propagating chronic sterile inflammation and the spread of CS. Hence, senescent cells in organs from older donors trigger the recipient's alloimmune response, resulting in the increased risk of graft loss. Eliminating senescent cells or attenuating their inflammatory phenotype is a novel, potential therapeutic target to improve transplant outcomes and expand utilization of organs from older donors. This review focuses on the current knowledge about the impact of CS on circulating immune cells in the context of organ damage and disease progression, discusses the impact of CS on abdominal solid organs that are commonly transplanted, and reviews emerging therapies that target CS.

Pneumocystis jirovecii Pneumonia in a Liver Transplant Recipient With an Adverse Reaction to Trimethoprim/Sulfamethoxazole Treated With a Sulfonamide Desensitization Protocol: Case Report

BACKGROUND

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that, in immunocompromised patients, can progress to respiratory failure and death. Since trimethoprim/sulfamethoxazole (TMP/SMX) chemoprophylaxis has become a standard management, the prognosis has improved. However, there are patients with a history of TMP/SMX intolerance who cannot receive chemoprophylaxis.

BACKGROUND

We report on a 53-year-old male liver recipient treated with a standard triple immunosuppressive regimen in whom TMP/SMX was waived because of a history of allergy manifested as a generalized rash with edema more than 30 years ago. At transplantation, the immunologic risk was assessed as low, and liver graft function was normal. In the third month after engraftment, he developed dyspnea at rest required constant passive oxygen therapy. Ceftriaxone, azithromycin, and clindamycin were implemented. Mycophenolate acid was stopped, and tacrolimus was reduced. High-resolution computed tomography revealed interstitial pneumonia. Pneumocystis jirovecii pneumoniae was diagnosed from bronchoalveolar lavage. Instead of TMP/SMX, pentamidine and caspofungin were also used for PJP, with no improvement. After 3 weeks, the patient deteriorated. Because of his life-threatening condition, TMP/SMX was introduced in the sulfonamide desensitization protocol, including hydrocortisone and clemastinum. Within 4 days, the patient stabilized with no signs of TMP/SMX intolerance. Pneumonia subsided within a month, and TMP/SMX was prescribed lifelong.

CONCLUSIONS

Prophylaxis for PJP with TMP/SMX still remains an important issue in transplant recipients. Adverse reaction to TMP/SMX in the past is not always a contraindication to reintroducing prophylaxis. The decision of prophylaxis avoidance should be analyzed carefully; in uncertain cases, a sulfonamide desensitization protocol should be considered.

Detrimental impact of immunosuppressive burden on clinical course in patients with Cytomegalovirus infection after liver transplantation

INTRODUCTION

Cytomegalovirus (CMV)-infection and reactivation remain a relevant complication after liver transplantation (LT). The recipient and donor serum CMV-IgG-status has been established for risk stratification when choosing various pharmaceutical regimens for CMV-prophylaxis in the last two decades. However, factors influencing course of CMV-infection in LT remain largely unknown. In this study, the impact of immunosuppressive regimen was examined in a large cohort of patients.

METHODS

All patients that underwent primary LT between 2006 and 2018 at the Charité-Universitaetsmedizin, Berlin, were included. Clinical course as well as histological and laboratory findings of patients were analyzed our prospectively maintained database. Univariate and multivariate regression analysis for impact of variables on CMV-occurrence was conducted, and survival was examined using Kaplan-Meier analysis.

RESULTS

Overall, 867 patients were included in the final analysis. CMV-infection was diagnosed in 325 (37.5%) patients after transplantation. Significantly improved overall survival was observed in these patients (Log rank = 0.03). As shown by correlation and regression tree classification and regression tree analysis, the recipient/donor CMV-IgG-status with either positivity had the largest influence on CMV-occurrence. Analysis of immunosuppressive burden did not reveal statistical impact on CMV-infection, but statistically significant inverse correlation of cumulative tacrolimus trough levels and survival was found (Log rank < .001). Multivariate analysis confirmed these findings (p = .02).

DISCUSSION

CMV-infection remains of clinical importance after LT. Undergone CMV-infection of either recipient or donor requires prophylactic treatment. Additionally, we found a highly significant, dosage-dependent impact of immunosuppression (IS) on long-term outcomes for these patients, underlying the importance of minimization of IS in liver transplant recipients.

Vaccine-Preventable Illness Leads to Adverse Outcomes in Liver Transplant Recipients

BACKGROUND

Liver transplant recipients (LTR) and patients with chronic liver disease (CLD) are at an increased risk of infections.

AIMS

The objective of our study was to assess the incidence, and impact of vaccine preventable illness (VPI) on outcomes in LTR.

METHODS

National Inpatient Sample (NIS) 2016-2020 was used to identify adults (age > 18) hospitalized LTR using ICD-10 codes. Data were collected on patient demographics, hospital characteristics, etiology of liver disease, hepatic decompensations and outcomes. Patients were stratified into two groups based on the presence or absence of VPI. Multivariate logistic regression analysis was performed to identify the association between VPI and outcomes.

RESULTS

Out of 170,650 hospitalized LTR, 13.5% of the patients had VPI. The most common VPI was noted to be influenza (10.7%), followed by pneumococcal infection (2.7%). Incidence of mortality (6.9% vs. 1.6%, p < 0.001), ICU admissions (14.3% vs. 3.4%, p < 0.001), and acute kidney injury (AKI) (43.7% vs 37.35%, p < 0.001) was higher in the VPI group.

CONCLUSION

More than 13% of the LT hospitalizations had concomitant VPI. VPI in LTR was associated with worse outcomes. Our data suggests the need to identify factors associated with reduced vaccination rates and identify strategies to improve vaccination rates and responses in these patients.

Mortality and Morbidity Among Adult Liver Retransplant Recipients

BACKGROUND

Liver transplantation (LT) is life-saving procedure for patients with end-stage liver failure with up to 20% of patients suffering graft failure following primary transplantation. Retransplantation (ReLT) remains the only definitive treatment for irreversible graft failure.

AIMS

We aimed to explore the postoperative outcomes following liver ReLT.

METHODS

Patients who had received a liver transplant between 2003 and 2016 were retrospectively identified using the Scientific Registry of Transplant Recipients (SRTRs). Patients were stratified based on previous liver transplant history. The primary outcomes of this study were 5-year postoperative mortality, morbidity, and length of hospital stay following LT.

RESULTS

60,554 (96%) recipients were first LT recipients and 2524 (4%) were ReLT recipients. Compared with first LT, ReLT recipients had significantly higher rates of mortality (OR 1.93, 95%CI 1.76-2.12), overall morbidity (OR 1.80, 95%CI 1.65-1.96), and prolonged length of stay (OR 1.66, 95%CI 1.52-1.81) on multivariate analysis. Morbidity including cardiovascular (CVD) complications (OR 1.32, 95%CI 1.08-1.60), graft failure (OR 2.18, 95%CI 1.84-2.57), infection (OR 2.13, 95%CI 1.82-2.50), and hemorrhage (OR 2.67, 95%CI 2.00-3.61) were significantly greater in ReLT recipients. Compared to first LT, ReLT patients had a significant increase in overall 5-year mortality (p < 0.001), 5-year mortality due to CVD complications (p < 0.001), infection (p = 0.009), but not graft failure (p = 0.3543).

CONCLUSION

ReLT is associated with higher rates of 5-year mortality, overall morbidity, CVD morbidity, infection, and graft failure. Higher 5-year mortality in ReLT is due to CVD and infections. These results could be used in preoperative patient assessment and prognostic counseling for ReLT.

Invasive aspergillosis in liver transplant recipients, an infectious complication with low incidence but significant mortality

BACKGROUND

Infections, including invasive fungal infections (IFIs), are among the leading causes of mortality in liver transplant recipients during the first year post-transplantation.

AIM

To investigate the epidemiology, clinical manifestations, risk factors, treatment outcomes, and mortality rate of post-liver transplantation invasive aspergillosis (IA).

METHODS

In this case-control study, 22 patients with IA were identified by reviewing the archived and electronic medical records of 850 patients who received liver transplants at the Imam Khomeini Hospital complex in Tehran, Iran, between 2014 and 2019. The control group comprised 38 patients without IA infection matched for age and sex. The information obtained included the baseline characteristics of liver transplant patients, operative reports, post-transplantation characteristics of both groups and information about the fungal infection of the patient group.

RESULTS

The prevalence rate of IA among liver transplant recipients at Imam Khomeini Hospital was 2.7%. The risk factors of IA among studied patients included high serum creatinine levels before and post-transplant, renal replacement therapy, antithymocyte globulin induction therapy, post-transplant bile leakage, post-transplant hepatic artery thrombosis, repeated surgery within 30 d after the transplant, bacterial pneumonia before the aspergillosis diagnosis, receiving systemic antibiotics before the aspergillus infection, cytomegalovirus infection, and duration of post-transplant hospitalization in the intensive care unit. The most prevalent form of infection was invasive pulmonary aspergillosis, and the most common chest computed tomography scan findings were nodules, pleural effusion, and the halo sign. In the case group, prophylactic antifungal therapy was administered more frequently than in the control group. The antifungal therapy response rate at 12 wk was 63.7%. The 3- and 12- mo mortality rates of the patients with IA were 36.4% and 45.4%, respectively (compared with the mortality rate of the control group in 12 mo, which was zero).

CONCLUSION

In this study, the prevalence of IA among liver transplant recipients was relatively low. However, it was one of the leading causes of mortality following liver transplantation. Targeted antifungal therapy may be a factor in the low incidence of infections at our facility. Identifying the risk factors of IFIs, maintaining an elevated level of clinical suspicion, and initiating early antifungal treatment may significantly improve the prognosis and reduce the mortality rate of liver transplant recipients.

Pretransplant Renal Dysfunction Negatively Affects Prognosis After Living Donor Liver Transplantation: A Single-Center Retrospective Study

BACKGROUND

To evaluate the influence of preoperative renal function on prognosis after living donor liver transplantation (LDLT).

METHODS

Living donor liver transplantation cases were categorized into 3 groups as follows: renal failure with hemodialysis (HD; n = 42), renal dysfunction (RD; n = 94) (glomerular filtration rate <60 mL/min/1.73 m2), and normal renal function (NF; n = 421). The study used no prisoners, and participants were neither coerced nor paid. The manuscript complies with the Helsinki Congress and the Declaration of Istanbul.

RESULTS

Five-year overall survival (OS) rates were 59.0%, 69.3%, and 80.0% in the HD, RD, and NF groups, respectively (P < .01). The frequency of bacteremia within 90 days after LDLT was 76.2%, 37.2%, and 34.7%, respectively (P < .01 in HD vs RD and HD vs NF). Patients with bacteremia showed a worse outcome than those without (1-year OS, 65.6% vs 93.3%), thus corroborating the poor prognosis in the HD group. The high frequency of bacteremia in the HD group was mainly attributable to health care-associated bacterium, such as coagulase-negative Staphylococci, Enterococcus spp., and Pseudomonas aeruginosa. In the HD group, HD was started within 50 days before LDLT for acute renal failure in 35 patients, of which 29 (82.9%) successfully withdrew from HD after LDLT and demonstrated better prognosis (1-year OS, 69.0% vs 16.7%) than those who continued HD.

CONCLUSIONS

Preoperative renal dysfunction is associated with poor prognosis after LDLT, possibly due to a high incidence of health care-associated bacteremia.

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.

Invasive Fungal Infections after Liver Transplantation

Invasive fungal infections represent a major challenge in patients who underwent organ transplantation. Overall, the most common fungal infections in these patients are candidiasis, followed by aspergillosis and cryptococcosis, except in lung transplant recipients, where aspergillosis is most common. Several risk factors have been identified, which increase the likelihood of an invasive fungal infection developing after transplantation. Liver transplant recipients constitute a high-risk category for invasive candidiasis and aspergillosis, and therefore targeted prophylaxis is favored in this patient population. Furthermore, a timely implemented therapy is crucial for achieving optimal outcomes in transplanted patients. In this article, we describe the epidemiology, risk factors, prophylaxis, and treatment strategies of the most common fungal infections in organ transplantation, with a focus on liver transplantation.

Incidence of Invasive Fungal Infections in Liver Transplant Recipients under Targeted Echinocandin Prophylaxis

Invasive fungal infections (IFIs) are one of the most important infectious complications after liver transplantation, determining morbidity and mortality. Antimycotic prophylaxis may impede IFI, but a consensus on indication, agent, or duration is still missing. Therefore, this study aimed to investigate the incidence of IFIs under targeted echinocandin antimycotic prophylaxis in adult high-risk liver transplant recipients. We retrospectively reviewed all patients undergoing a deceased donor liver transplantation at the Medical University of Innsbruck in the period from 2017 to 2020. Of 299 patients, 224 met the inclusion criteria. We defined patients as being at high risk for IFI if they had two or more prespecified risk factors and these patients received prophylaxis. In total, 85% (190/224) of the patients were correctly classified according to the developed algorithm, being able to predict an IFI with a sensitivity of 89%. Although 83% (90/109) so defined high-risk recipients received echinocandin prophylaxis, 21% (23/109) still developed an IFI. The multivariate analysis identified the age of the recipient (hazard ratio-HR = 0.97, p = 0.027), split liver transplantation (HR = 5.18, p = 0.014), massive intraoperative blood transfusion (HR = 24.08, p = 0.004), donor-derived infection (HR = 9.70, p < 0.001), and relaparotomy (HR = 4.62, p = 0.003) as variables with increased hazard ratios for an IFI within 90 days. The fungal colonization at baseline, high-urgency transplantation, posttransplant dialysis, bile leak, and early transplantation showed significance only in a univariate model. Notably, 57% (12/21) of the invasive Candida infections were caused by a non-albicans species, entailing a markedly reduced one-year survival. The attributable 90-day mortality rate of an IFI after a liver transplant was 53% (9/17). None of the patients with invasive aspergillosis survived. Despite targeted echinocandin prophylaxis, there is still a notable risk for IFI. Consequently, the prophylactic use of echinocandins must be critically questioned regarding the high rate of breakthrough infections, the increased occurrence of fluconazole-resistant pathogens, and the higher mortality rate in non-albicans Candida species. Adherence to the internal prophylaxis algorithms is of immense importance, bearing in mind the high IFI rates in case algorithms are not followed.

Pharmacokinetic and pharmacodynamic considerations of antibiotics and antifungals in liver transplantation recipients

The liver plays a major role in drug metabolism. Liver transplantation impacts the intrinsic metabolic capability and extrahepatic mechanisms of drug disposition and elimination. Different levels of inflammation and oxidative stress during transplantation, the process of liver regeneration, and the characteristics of the graft alter the amount of functional hepatocytes and activity of liver enzymes. Binding of drugs to plasma proteins is affected by the hyperbilirubinemia status and abnormal synthesis of albumin and alpha-1-acid glycoproteins. Postoperative intensive care complications such as biliary, circulatory, and cardiac also impact drug distribution. Renally eliminated antimicrobials commonly present reduced clearance due to hepatorenal syndrome and the use of nephrotoxic immunosuppressants. In addition, liver transplantation recipients are particularly susceptible to multidrug-resistant infections due to frequent manipulation, multiple hospitalizations, invasive devices, and frequent use of empiric broad-spectrum therapy. The selection of appropriate anti-infective therapy must consider the pathophysiological changes after transplantation that impact the pharmacokinetics and pharmacodynamics of antibiotics and antifungal drugs.

Epidemic, risk factors of carbapenem-resistant Klebsiella pneumoniae infection and its effect on the early prognosis of liver transplantation

Background

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection remains a major cause of morbidity and mortality in early-stage post-liver transplantation (LT).

Methods

We retrospectively analyzed the demographic and clinical infections characteristics of all LT recipients in our hospital between January 2019 and December 2021.

Results

Among the 272 LT recipients who received LT between January 2019 and December 2021, sixty-two patients had at least one infection within 3-months post-LT, with a prevalence of 22.8% (62/272). The prevalence of CRKP infections was 7.0% (19/272), and the 3-months post-LT mortality was 19.4% (12/62). The risk factors independently related to 3-months mortality were age (Odds ratio (OR)= 1.126, 95% Confidence interval (CI): 1.009~1.257; P=0.034), mechanical ventilation (MV) (OR=1.206, 95% CI: 1.039~1.401; P =0.014), and CRKP infection (OR=18.240, 95% CI: 2.206~150.842; P =0.007). In CRKP infection, the length of ICU stay (OR=1.067, 95% CI: 1.015~1.122; P=0.011), pre-operation infection (POI) (OR=6.733, 95% CI: 1.160~39.088; P=0.034), and hepatocellular carcinoma (HCC) (OR=26.772, 95% CI: 1.747~410.187; P=0.018) were the independent risk factors. With COX multivariate regression analysis, the 3-months survival rate of CRKP infected patients was significantly lower than that without CRKP infection post-LT.

Conclusions

CRKP infection is closely correlated with poor prognosis in 3-months post-LT.

Bacteriophage-antibiotic combination therapy against extensively drug-resistant Pseudomonas aeruginosa infection to allow liver transplantation in a toddler

Post-operative bacterial infections are a leading cause of mortality and morbidity after ongoing liver transplantation. Bacteria causing these infections in the hospital setting can exhibit high degrees of resistance to multiple types of antibiotics, which leads to major therapeutic hurdles. Alternate ways of treating these antibiotic-resistant infections are thus urgently needed. Phage therapy is one of them and consists in using selected bacteriophage viruses - viruses who specifically prey on bacteria, naturally found in various environmental samples - as bactericidal agents in replacement or in combination with antibiotics. The use of phage therapy raises various research questions to further characterize what determines therapeutic success or failure. In this work, we report the story of a toddler who suffered from extensively drug-resistant Pseudomonas aeruginosa sepsis after liver transplantation. He was treated by a bacteriophage-antibiotic intravenous combination therapy for 86 days. This salvage therapy was well tolerated, without antibody-mediated phage neutralization. It was associated with objective clinical and microbiological improvement, eventually allowing for liver retransplantation and complete resolution of all infections. Clear in vitro phage-antibiotic synergies were observed. The occurrence of bacterial phage resistance did not result in therapeutic failure, possibly due to phage-induced virulence tradeoffs, which we investigated in different experimental models.

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.

Bacterial and Viral Infections in Liver Transplantation: New Insights from Clinical and Surgical Perspectives

End-stage liver disease patients undergoing liver transplantation are prone to develop numerous infectious complications because of immunosuppression, surgical interventions, and malnutrition. Infections in transplant recipients account for the main cause of mortality and morbidity with rates of up to 80%. The challenges faced in the early post-transplant period tend to be linked to transplant procedures and nosocomial infections commonly in bloodstream, surgical, and intra-abdominal sites. Viral infections represent an additional complication of immunosuppression; they can be donor-derived, reactivated from a latent virus, nosocomial or community-acquired. Bacterial and viral infections in solid organ transplantation are managed by prophylaxis, multi-drug resistant screening, risk assessment, vaccination, infection control and antimicrobial stewardship. The aim of this review was to discuss the epidemiology of bacterial and viral infections in liver transplants, infection control issues, as well as surgical frontiers of ex situ liver perfusion.

Implications and Management of Cirrhosis-Associated Immune Dysfunction Before and After Liver Transplantation

Cirrhosis-associated immune dysfunction (CAID) describes a panacea of innate and adaptive deficits that result from the sequelae of cirrhotic portal hypertension that is similar in its manifestations regardless of etiology of chronic liver injury. CAID is associated with synchronous observations of dysregulated priming of innate immune effector cells that demonstrate a proinflammatory phenotype but are functionally impaired and unable to adequately prevent invading pathogens. CAID is mainly driven by gut-barrier dysfunction and is associated with deficits of microbial compartmentalization and homeostasis that lead to tonic activation, systemic inflammation, and exhaustion of innate-immune cells. CAID leads to a high frequency of bacterial and fungal infections in patients with cirrhosis that are often associated with acute decompensation of chronic liver disease and acute-on-chronic liver failure and carry a high mortality rate. Understanding the deficits of mucosal and systemic immunity in the context of chronic liver disease is essential to improving care for patients with cirrhosis, preventing precipitants of acute decompensation of cirrhosis, and improving morbidity and survival. In this review, we summarize the detailed dynamic immunological perturbations associated with advanced chronic liver disease and highlight the importance of recognizing immune dysregulation as a sequela of cirrhosis. Furthermore, we address the role of screening, prevention, and early treatment of infections in cirrhosis in improving patient outcomes in transplant and nontransplant settings.

Invasive Pulmonary Aspergillosis and Tuberculosis Complicated by Hemophagocytic Lymphohistiocytosis - Sequelae of COVID-19 in a Liver Transplant Recipient

Liver transplant recipients are at an increased risk of opportunistic infections due to the use of immunosuppression. Coronavirus disease of 2019 (COVID-19) increases the risk of these infections further due to associated immune dysfunction and the use of high-dose steroids. We present a case of a liver transplant recipient who developed disseminated tuberculosis and invasive pulmonary aspergillosis complicated by acquired hemophagocytic lymphohistiocytosis after recovering from severe COVID-19.

Epidemiology and long-term outcomes of cytomegalovirus DNAemia and disease in pediatric solid organ transplant recipients

Despite prevention strategies, cytomegalovirus (CMV) remains a common infection in pediatric solid organ transplant recipients (SOTR). We sought to determine the frequency, associations with, and long-term outcomes of CMV DNAemia in pediatric SOTR. We performed a single-center retrospective cohort study, including 687 first time SOTR ≤21 years receiving universal prophylaxis from 2011 to 2018. Overall, 159 (23%) developed CMV DNAemia, the majority occurring after completing primary prophylaxis. CMV disease occurred in 33 (5%) SOTR, 25 (4%) with CMV syndrome and 10 (1%) with proven/probable tissue-invasive disease. CMV contributed to the death of three (0.4%) patients (all lung). High-risk (OR 6.86 [95% CI, 3.6-12.9]) and intermediate-risk (4.36 [2.3-8.2]) CMV status and lung transplantation (4.63 [2.33-9.2]) were associated with DNAemia on multivariable analysis. DNAemia was associated with rejection in liver transplant recipients (p < .01). DNAemia was not associated with an increase in graft failure, all-cause mortality, or other organ-specific poor outcomes. We report one of the lowest rates of CMV disease after SOTR, showing that universal prophylaxis is effective and should be continued. However, we observed CMV morbidity and mortality in a subset of patients, highlighting the need for research on optimal prevention strategies. This study was IRB approved.

Pharmacokinetics/Pharmacodynamics of caspofungin in plasma and peritoneal fluid of liver transplant recipients

Background: The weaker diffusion of echinocandins in the peritoneal fluid (PF) could promote Candida resistant isolates. The aim of this study was to analyse the pharmacokinetics/pharmacodynamics (PK/PD) of caspofungin in plasma and PF of liver transplant recipients.Methods: Liver transplant patients received caspofungin as postoperative prophylaxis. Caspofungin concentrations were quantified in plasma and in PF on Days 1, 3 and 8. Data were analysed using non-linear mixed-effect modelling and Monte Carlo simulations. Area under curve (AUC) in plasma and PF were simulated under three dosing regimens. Probabilities of target attainment (PTA) were calculated using fAUC_0-24/minimal inhibitory concentration (MIC) ratios with MICs ranging from 0.008 to 8 mg/litre. All the patients included were monitored weekly for Candida colonisation and for Candida infections.Results: Twenty patients were included. Median daily dose of caspofungin was 0.81 mg/kg. Plasma (n=395) and peritoneal (n=50) concentrations at steady state were available. A two-compartment model with first-order absorption and elimination was described. Our two-compartment model with first-order absorption and elimination model produced an effective PK/PD relationship in plasma, achieving a PTA ≥90% and MIC ranging from 0.008 to 0.12 mg/L for C. albicans and glabrata. In PF, PTAs at D8 were only optimal for a MIC of 0.008 in patients weighing 60 kg under the three dosing regimens. Among the 16 patients colonized, all MIC values were below the maximal concentration (Cmax) in plasma but not in PF.Conclusion: Peritoneal concentrations of caspofungin were low. Simulations showed that the PTA for Candida spp. in PF were not optimal, that might suggesting a potential risk of resistance.

Early post-liver transplantation infections and their effect on long-term survival

BACKGROUND

Infections post-liver transplantation are major drivers for morbidity and mortality. However, the impact of infections within 180 days post-liver transplantation on long-term survival is not clear.

METHODS

We present a retrospective cohort of 317 liver transplant patients for whom all infectious episodes were prospectively collected during a mean follow-up of 4.4 years.

RESULTS

A total of 143/317 (45%) of patients suffered from any infectious episode during the first 6 months following liver transplantation. Patients with surgical site infections have a reduced survival compared to those with no infection (HR 0.33, 95% CI 0.172-0.636, P = .001), whereas infections from other sources, including pneumonia, UTI, and line-related infections, were not associated with increased mortality. Furthermore, even though the presence of any infection within 30 days or 6 months post-transplantation did not affect survival, more than a single infectious episode per patient was significantly associated with increased mortality (HR 1.70, CI 1.12-2.60, P = .013). In a multivariate analysis, the number of infectious episodes remained statistically significant (HR 1.58, 95% CI 1.03-2.43, P = .035) upon adjustment for other major variables associated with comorbidities and infection risk.

CONCLUSIONS

Surgical site infections and the number of infectious episodes within 180 days post-liver transplantation are major determinants of long-term survival among these patients.

Mixed and disseminated paracoccidioidomycosis after liver transplantation: Case report

Paracoccidioidomycosis (PCM) is a systemic granulomatous fungal infection rarely associated with solid organ transplantation. We report the second case of PCM in an adult after liver transplantation. A 47-year-old woman who had undergone liver transplantation was hospitalized for flu-like symptoms and multiple erythematous ulcerated skin papules. There was lymphadenopathy, pulmonary compromise, and quickly progression to septic shock. PCM was confirmed by skin biopsy and serologic tests, and a satisfactory response to amphotericin B was achieved.

Catastrophic Brain Aspergillosis after Liver Transplantation

Background. Liver transplantation has many complications. Because of receiving immunosuppressive regimens, infectious complications in these patients may have fatal results. Aspergillosis in solid organ recipients is one of the most common fungal infections that usually occur 1 month after transplantation. Aspergillus infection mainly involves the lungs. Although the central nervous system may get involved due to hematogenous spreading from lungs, isolated central nervous system involvement is rarely reported. Case Presentation. The patient was an 8-year-old boy, with a case of Wilson disease, who underwent liver transplantation due to acute fulminant hepatic failure. Four days after the surgery, he was affected by fever, agitation, loss of consciousness, hemiparesis, and focal seizure. Brain MRI showed abscess formation, whereas chest X-ray was normal. Intravenous antibiotics were initiated but the patient's condition was not improving; therefore, surgical drainage of the abscess was performed. The pathological investigation was compatible with aspergillosis. Antifungal therapy with voriconazole was administrated. His symptoms were resolved but unfortunately, brain lesions caused persistent vegetative state. Discussion. Aspergillus is a ubiquitous organism that mainly occurs in immunocompromised patients. Aspergillosis could be prevented by environmental modification such as installing high-efficiency particulate air filters. Chemoprevention with triazoles, echinocandins, and polyenes is also effective. Voriconazole is the drug of choice for aspergillosis treatment. Although voriconazole is a highly effective antifungal drug, cerebral aspergillosis is often fatal.

Intracerebral Hemorrhage Related With Penicillium Species Following Deceased-Donor Liver Transplant

Early or late posttransplant opportunistic infections are among the leading complications after liver transplant. The source of early posttransplant opportunistic infections is usually the patient, the implantation of an infected graft, contamination during a surgical procedure, or invasive interventions performed at the intensive care unit. A 10-year-old male patient with Wilson disease (Pediatric End-Stage Liver Disease Score of 42, Child-Pugh score of 12, total bilirubin 40 mg/dL, platelet count 55000/mL, hemoglobin level 6.3 g/dL, albumin level 1.7 g/dL, urinary copper level 4305 μ/24 h) was closely monitored in the pediatric intensive care unit of our liver transplantation center for care of a worsened general status. A deceased-donor liver transplant was performed using a right lobe liver graft (ex vivo split) obtained through the national organ sharing network. The patient developed rightward deviation of eyes and altered consciousness after the procedure and underwent cranial magnetic resonance imaging and computerized tomography examinations. The cranial magnetic resonance image, taken on the third postoperative day, revealed lesions consistent with embolic infarction, and the computed tomography scan, taken on the eighth day, showed intracerebral hemorrhage. Decompressive craniotomy, which included hematoma drainage and catheter placement, was performed. Culture and histopathologic examinations of the hematoma material revealed a Penicillium species of fungi. However, the patient died before a definitive diagnosis was made. The aim of this report is to raise awareness on early posttransplant opportunistic infections of the central nervous system presenting with intracranial hemorrhage following liver transplant.

Risk Factors and Outcomes of Carbapenem-Resistant Enterobacteriaceae Infection After Liver Transplantation: A Retrospective Study in a Chinese Population

Background

There is an increasing prevalence of carbapenem-resistant Enterobacteriaceae (CRE) infection after liver transplantation (LT). Improved understanding of the risk factors and outcomes of CRE infections can help us to develop effective preventive strategies and even guide early treatment of high-risk LT patients.

Methods

This was a retrospective study involving all Chinese adult patients who underwent LT between December 2017 and September 2019 in our center. We analyzed the possible risk factors and outcomes associated with CRE infections in the first 30 days post-LT.

Results

A total of 387 patients underwent LT. Among them, 26 patients (6.7%) developed CRE infections within 30 days after transplantation. Patients with CRE infections had significantly lower 30-day and 180-day survival rates (80.8% vs 96.4%, p<0.001; 51.5% vs 92.4%, p<0.001). Multivariate analysis identified that intraoperative blood loss equal to or more than 1500 mL (odds ratio [OR], 3.666; 95% confidence interval [CI], 1.407-9.550; p=0.008), CRE rectal carriage within 30 days post-LT (OR, 5.516; 95% CI, 2.113-14.399; p=0.000), biliary complications (OR, 3.779; 95% CI, 1.033-13.831; p=0.045) and renal replacement therapy for more than 3 days (OR, 3.762; 95% CI, 1.196-11.833; p=0.023) were independent risk factors for CRE infections within 30 days post-LT.

Conclusion

CRE infections within 30 days post-LT were associated with worse outcomes. Intraoperative blood loss equal to or more than 1500 mL, CRE rectal carriage within 30 days post-LT, biliary complications and renal replacement therapy for more than 3 days were independent risk factors of CRE infections after LT.

Galactose Functionalized Mesoporous Silica Nanoparticles As Delivery Vehicle in the Treatment of Hepatitis C Infection

DNA and RNA based antiviral strategies using nonviral vectors have shown better potential over the viral pathway due to the fewer chances of gene recombination and immunogenicity. In this work a mesoporous silica nanoparticle (MSN) based carrier system has been used for targeted delivery of shDNA molecule against the conserved 5'-untranslated region (UTR) in the RNA of a hepatitis C virus to inhibit its replication. The MSNs coated with amine and galactose could specifically target liver cells. Significant reduction (about 94%) of viral RNA level was achieved in HCV-JFH1 infectious cell culture compared to the control RNA levels directed the successful delivery and action of the shDNA. This study showed that Gal-AMSN can be used as a synthetic delivery vector to deliver the shDNA effectively for the treatment of HCV infection.

Thirty-day readmission rates, trends and its impact on liver transplantation recipients: a national analysis

Reduction of early hospital readmissions is a declared goal in the United States economic and quality improvement agenda. A retrospective study was performed using the Nationwide Readmissions Database from 2010 to 2014. Our primary aim was to study the rate of early readmissions and its predictors in liver transplant recipients (LTRs). Our secondary aims were to determine the trends of LT, reasons for readmission, costs and predictors of calendar year mortality. Multivariable logistic regression and Cox proportional hazards models were utilized. The 30-day readmission rate was 30.6% among a total of 25,054 LTRs. Trends of LT were observed to be increased in patients > 65 years (11.7-17.8%, p < 0.001) and decreased in 40-64 years (78.0-73.5%, p = 0.001) during study period. The majority of 30-day readmissions were due to post transplant complications, with packed red blood cell transfusions being the most common intervention during readmission. Medicaid or Medicare insurance, surgery at low and medium volume centers, infections, hemodialysis, liver biopsy, and length of stay > 10 days were the predictors of 30-day readmission. Moreover, number of early readmission, age > 64 years, non-alcoholic cirrhosis, and length of stay > 10 days were significant predictor of calendar year mortality in LTRs. Approximately one third of patients require early admission after LT. Early readmission not only increases burden on healthcare, but is also associated with calendar year mortality. Strategies should be implemented to reduce readmission in patients with high risk of readmission identified in our study.

Effects of Coronavirus Disease 2019 on Solid Organ Transplantation

BACKGROUND

As the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emerged as a viral pandemic, data on the clinical characteristics and outcomes of patients with SARS-CoV-2 infection undergoing solid organ transplant are emerging. The objective of this systematic review was to assess currently published literature relating to the management, clinical course, and outcome of SARS-CoV-2 infection in liver, kidney, and heart solid organ transplant recipients.

METHODS

We conducted a systematic review to assess currently published literature relating to the management, clinical course, and outcome of SARS-CoV-2 infection in liver, kidney, and heart solid organ transplant recipients. Articles published through June 2020 were searched in the MEDLINE, ClinicalTrials.gov, and PubMed databases. We identified 49 eligible studies comprising a total of 403 solid organ transplant recipients.

RESULTS

Older age, male sex, and preexisting comorbidities, including hypertension and/or diabetes, were the most common prevailing characteristics among the solid organ transplant recipients. Clinical presentation ranged from mild to severe disease, including multiorgan failure and death. We found an overall mortality rate of 21%.

CONCLUSION

Our analysis suggests no increase in overall mortality or worse outcome in solid organ transplant recipients receiving immunosuppressive therapy compared with mortality in the general surgical population with SARS-CoV-2. Our findings suggest that transplant surgery and its immunosuppressive effects should not be a deterrent to proper surgical care for patients in the SARS-CoV-2 era.

Infection within 2 weeks before liver transplantation closely related to prognosis of posttransplant infection: A single-center retrospective observational study in China

BACKGROUND

Infections still represent the main factors influencing morbidity and mortality following liver transplantation. This study aimed to evaluate the incidence and risk factors for infection and survival after liver transplantation.

METHODS

We retrospectively examined medical records in 210 liver recipients who underwent liver transplantation between April 2015 and October 2017 in our hospital. Clinical manifestations and results of pathogen detection test were used to define infection. We analyzed the prevalence, risk factors and prognosis of patients with infection.

RESULTS

The median follow-up was 214 days; the incidence of infection after liver transplantation was 46.7% (n = 98) which included pneumonia (43.4%), biliary tract infection (21.9%), peritonitis (21.4%) and bloodstream infection (7.6%). Among the pathogens in pneumonia, the most frequently isolated was Acinetobacter baumanii (23.5%) and Klebsiella pneumoniae (21.2%). Model for end-stage liver disease (MELD) score (OR = 1.083, 95% CI: 1.045-1.123; P < 0.001), biliary complication (OR = 4.725, 95% CI: 1.119-19.947; P = 0.035) and duration of drainage tube (OR = 1.040, 95% CI: 1.007-1.074; P = 0.017) were independent risk factors for posttransplant infection. All-cause mortality was 11.0% (n = 23). The prognostic factors for postoperative infection in liver recipients were prior-transplant infection, especially pneumonia within 2 weeks before transplantation. Kaplan-Meier curves of survival showed that recipients within 2 weeks prior infection had a significantly lower cumulative survival rate compared with those without infection (65.2% vs. 90.0%; hazard ratio: 4.480; P < 0.001).

CONCLUSIONS

Infection, especially pneumonia within 2 weeks before transplantation, complication with impaired renal function and MELD score after 7 days of transplantation was an independent prognostic factor for postoperative infection in liver transplant recipients.

Early Bacterial Infections After Pediatric Liver Transplantation in the Era of Multidrug-resistant Bacteria: Nine-year Single-center Retrospective Experience

BACKGROUND

Early bacterial infection is a major and severe complication after liver transplantation (LT). The rise of antimicrobial resistance, especially extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE), is a growing concern for these patients. This study aimed to assess the epidemiology of early bacterial infections in a pediatric population, including those caused by multidrug-resistant (MDR) pathogens, and to identify risk factors for infection.

METHODS

We conducted a monocentric retrospective study including 142 consecutive LTs performed in 137 children between 2009 and 2017.

RESULTS

Ninety-three bacterial infections occurred after 67 (47%) LTs. Among the 82 isolated pathogens, the most common was Klebsiella pneumoniae (n = 19, 23%). Independent risk factors for early bacterial infection were low weight [odds ratio (OR) = 0.96; 95% confidence interval (CI): 0.9-0.99; P = 0.03] and the presence of a prosthetic mesh (OR = 2.4; 95% CI: 1.1-5.4; P = 0.046). Sixty-one children (45%) carried MDR bacteria and 16 infections were caused by MDR pathogens, especially ESBL-producing K. pneumoniae (n = 12). ESBL-PE stool carriage was associated with ESBL-PE infection (OR = 4.5; 95% CI: 1.4-17.4; P = 0.02). Four children died from an infection, three due to ESBL-producing K. pneumoniae.

CONCLUSIONS

This study confirmed a shift toward a predominance of Gram-negative early bacterial infections after pediatric LT. The risk factors for infection were low weight and the presence of a prosthetic mesh. ESBL-PE stool carriage was associated with ESBL-PE infection. Adapted antimicrobial prophylaxis and personalized antibiotherapy are mandatory to reduce infection prevalence and mortality.

Interrelationship between Toll-like receptors and infection after orthotopic liver transplantation

Early microbial recognition by the innate immune system is accomplished by Toll-like receptors (TLRs), with resultant initiation of a pro-inflammatory response against infecting organisms. In spite of presence of an abundance of Toll-like receptors on the surface of the liver, gut bacteria does not elicit an inflammatory reaction in healthy individuals due to tolerance to these TLRs, suggesting that the inflammatory responses seen in the liver are the result of breakdown of this tolerance. While orthotopic liver transplantation is often life saving in many instances, death following this procedure is most commonly due to infection that occurs in up to 80% of transplant recipients, most commonly due to microbial causes in up to 70% of cases and viral infections in 20%, while fungal infections affect only 8% of cases. The probability of acquiring infection following hepatic transplantation is heightened due to affection of the innate immune defense mechanisms of the host following this procedure. Single nucleotide polymorphisms of TLRs have been associated with increased likelihood of either development of post-transplant infection or eradication of infecting organism. However, conflicting reports from other studies reveal that prevalence of this single nucleotide polymorphism is not increased in infected patients.

Bacterial and Fungal Infections After Liver Transplantation: Microbial Epidemiology, Risk Factors for Infection and Death with Infection

Background

Infections, especially bacterial and fungal infections, are the leading cause of high mortality after liver transplantation (LT). This research investigated the pathogenic spectrum, antimicrobial susceptibility results, and risk factors of infection and death with infection to better control such infections.

Material/Methods

A retrospective cohort study was performed, and 433 liver transplant recipients between January 2010 and December 2016 were analyzed.

Results

We found 290 isolates of bacteria and fungi in 170 infected liver transplant patients. Significant independent risk factors for bacterial and fungal infections were prolonged hospital stay (OR 1.034, 95% CI 1.013~1.056, p=0.002), mechanical ventilation (OR 3.806, 95% CI 1.567~9.248, p=0.003), and liver failure (OR 2.659, 95% CI 1.019~6.940, p=0.046). Furthermore, postoperative MELD scores (OR 1.120, 95% CI 1.020~1.230, p=0.017) and septic shock (OR 12.000, 95% CI 1.124~128.066, p=0.003) were independent risk factors for death with infection. CRAB infection is the main pathogenic bacteria of septic shock in LT patients.

Conclusions

We found that 39.3% of recipients had at least 1 bacterial or fungal infection after LT. Shortening the length of hospital stay and early withdrawal of mechanical ventilation will reduce the risk of infection after LT. Patients with liver failure should be more vigilant against postoperative infection. Once an infection occurs, immediate assessment of the postoperative MELD score, early diagnosis of septic shock, and active search for pathogenic evidence for precise treatment will help improve patient prognosis. Routine screening for CRAB colonization before surgery will facilitate empirical use of effective antibiotics.

Case Report: Paracoccidioidomycosis in Solid Organ Transplantation: Disseminated Disease in a Liver Recipient and Literature Review

Paracoccidioidomycosis (PCM) is an endemic systemic mycosis that is of great importance in Latin America. Its occurrence in solid organ transplantation (SOT) is rare, but with high mortality rate. In this report, we describe a case of PCM in a liver transplant recipient 19 months after transplantation. The patient presented with multiple skin abscesses, arthritis, osteolytic lesions, and pulmonary and adrenal involvement. Despite the presence of disseminated disease and the patient's immunosuppressed condition, the patient responded well to prolonged antifungal treatment with no sequelae, thus suggesting that early diagnosis and correct treatment may lead to favorable outcomes in SOT recipients with PCM.

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.

Very early-onset of Cryptococcus neoformans disease following liver transplantation: Report of two cases and a review of the literature

Cryptococcosis is the third most common invasive fungal infection following solid organ transplantation, and mortality is high. Most cases occur late and are due to reactivation of latent infection; however, very early reactivation and donor-derived transmission can occur. Routine screening pre-transplant and antifungal prophylaxis for cryptococcosis post-transplant in solid organ transplantation are not standard practice. We present two cases of very early-onset Cryptococcus neoformans disease following liver transplantation to highlight the need to consider individualized pre-transplant screening and be aware that reactivation of Cryptococcosis neoformans can occur in the immediate post-transplant period.

Infectious Lung Disease

Infectious diseases are one of the main causes of morbidity and mortality worldwide. With new pathogens continuously emerging, known infectious diseases reemerging, increasing microbial resistance to antimicrobial agents, global environmental change, ease of world travel, and an increasing immunosuppressed population, recognition of infectious diseases plays an ever-important role in surgical pathology. This becomes particularly significant in cases where infectious disease is not suspected clinically and the initial diagnostic workup fails to include samples for culture. As such, it is not uncommon that a lung biopsy becomes the only material available in the diagnostic process of an infectious disease. Once the infectious nature of the pathological process is established, careful search for the causative agent is advised. This can often be achieved by examination of the hematoxylin and eosin-stained sections alone as many organisms or their cytopathic effects are visible on routine staining. However, ancillary studies such as histochemical stains, immunohistochemistry, in situ hybridization, or molecular techniques may be needed to identify the organism in tissue sections or for further characterization, such as speciation.

Liver Transplantation and Early Culture Growth: Risk and Impact?

OBJECTIVE

Despite advances in immunosuppressive drugs, postoperative care, and surgical techniques, bacterial infections remain the most important cause of morbidity and mortality in liver transplant patients. The aim of this study is to evaluate the influence of culture results taken on the first day of admission to intensive care unit on mortality, graft rejection, mechanical ventilation duration, and length of intensive care unit stay. Our study has clinical importance because it is the first study evaluating the cultures obtained on the first day of intensive care unit stays in liver transplant patients.

METHODS

Patients' demographic data, transplant type, rates of deceased and living donors, culture results, amount of blood and blood products used intraoperatively, previous hospital admission, mortality, incidence of graft rejection, mechanical ventilation duration, and length of intensive care unit stay were recorded.

RESULTS

Mortality and graft rejection were 14.8% and 9%, respectively. The mortality was significantly higher in all 3 cultures and/or in only blood culture-positive patients. Graft rejection, mechanical ventilation duration, and length of intensive care unit stay were significantly higher in patients whose 3 cultures were all positive. Only body mass index had a significant effect on mortality, graft rejection, and positive culture results.

CONCLUSIONS

Liver transplant patients' first postoperative day culture results were correlated with mortality, graft rejection, mechanical ventilation duration, and length of intensive care unit stay.

Pre- and post-transplant bacterial infections in liver transplant recipients

BACKGROUND

Early (<1 month) bacterial infection after liver transplant is a major cause of morbidity and mortality among liver transplant recipients. We investigated the impact of pre-transplant bacterial infection on early post-transplant bacterial infection incidence and outcomes.

METHODS

A retrospective cohort study identified all patients who underwent liver transplantation between January 1, 2011, and December 31, 2012, at a single tertiary center in the United States. Infections occurring within the 30 days prior to transplant and within the 30 following transplant were identified. Information regarding pre-transplant morbidity and post-transplant outcomes was collected.

RESULTS

One-hundred seventy-four patients were included in the study. Forty patients (23%) experienced a total of 50 pre-transplant infections. Fifty-two (30%) developed a total of 62 post-transplant infections. Patients with a pre-transplant infection were more likely to develop a post-transplant infection compared to patients without a pre-transplant infection (48% [19 of 40] vs. 25% [33 of 134], respectively, P = .006). Patients with a pre-transplant infection had a longer mean post-transplant length of stay compared to those without a pre-transplant infection (16.3 days vs. 10.4 days, respectively, P < .001), but survival at 30 days was similar in both groups (95% [38 of 40] vs. 97% [130 of 134, respectively, P = .56).

CONCLUSIONS

Among liver transplant recipients, pre-transplant infection is an important risk factor for early post-transplant bacterial infections. Pre-transplant infection is associated with increased early morbidity but not mortality after transplant.

Leishmania donovani and Pneumocystis jirovecii (carinii) diagnosed on bronchoalveolar lavage cytology in a liver transplant recipient with Cytomegalovirus infection

Liver transplant recipients are prone to several infections, including lung infections, which can lead to substantial morbidity and mortality. Bronchoalveolar lavage (BAL) cytology is a rapid and sensitive diagnostic tool to identify the etiologic agents. We report a rare case of a 24-year-old male, post Live donor liver transplantation for autoimmune chronic liver disease, who presented with cough, fever, weight loss, and cavitatory lesion in lung. BAL cytology revealed Leishmania donovani (LD) and Pneumocystis jirovecii/carinii (PCP). Cytomegalovirus deoxyribonucleic acid polymerase chain reaction (CMV DNA PCR) test showed markedly raised levels. Patient was put on treatment for these multiple infections and showed significant improvement. Thus, rapid diagnosis of infections through BAL cytology is crucial in transplant recipients to institute timely therapy and avoid undesirable empirical treatments. Moreover, this case highlights a rare finding of LD bodies along with PCP in BAL cytology.

Intra-abdominal infections in solid organ transplant recipients: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

This new guideline from the AST IDCOP reviews intra-abdominal infections (IAIs), which cause substantial morbidity and mortality among abdominal SOT recipients. Each transplant type carries unique risks for IAI, though peritonitis occurs in all abdominal transplant recipients. Biliary infections, bilomas, and intra-abdominal and intrahepatic abscesses are common after liver transplantation and are associated with the type of biliary anastomosis, the presence of vascular thrombosis or ischemia, and biliary leaks or strictures. IAIs after kidney transplantation include renal and perinephric abscesses and graft-site candidiasis, which is uncommon but may require allograft nephrectomy. Among pancreas transplant recipients, duodenal anastomotic leaks can have catastrophic consequences, and polymicrobial abscesses can lead to graft loss and death. Intestinal transplant recipients are at the highest risk for sepsis, infection due to multidrug-resistant organisms, and death from IAI, as the transplanted intestine is a contaminated, highly immunological, pathogen-rich organ. Source control and antibiotics are the cornerstone of the management of IAIs. Empiric antimicrobial regimens should be tailored to local susceptibility patterns and pathogens with which the patient is known to be colonized, with subsequent optimization once the results of cultures are reported.

Antibiotics-mediated intestinal microbiome perturbation aggravates tacrolimus-induced glucose disorders in mice

Both immunosuppressants and antibiotics (ABX) are indispensable for transplant patients. However, the former increases the risk of new-onset diabetes, whereas the latter impacts intestinal microbiota (IM). It is still unclear whether and how the interaction between immunosuppressants and ABX alters the IM and thus leads to glucose metabolism disorders. This study examined the alterations of glucose and lipid metabolism and IM in mice exposed to tacrolimus (TAC) with or without ABX. We found that ABX further aggravated TAC-induced glucose tolerance and increased insulin secretion. Combined treatment resulted in exacerbated lipid accumulation in the liver. TAC-altered microbial community was further amplified by ABX administration, as characterized by reductions in phylum Firmicutes, family Lachnospiraceae, and genus Coprococcus. Analyses based on the metagenomic profiles revealed that ABX augmented the effect of TAC on microbial metabolic function mostly related to lipid metabolism. The altered components of gut microbiome and predicted microbial functional profiles showed significant correlation with hepatic lipid accumulation and glucose disorders. In conclusion, ABX aggravated the effect of TAC on the microbiome and its metabolic capacities, which might contribute to hepatic lipid accumulation and glucose disorders. These findings suggest that the ABX-altered microbiome can amplify the diabetogenic effect of TAC and could be a novel therapeutic target for patients.

Risk index for early infections following living donor liver transplantation

INTRODUCTION

Post-operative infections in patients undergoing living donor liver transplantation (LDLT) are a major cause of morbidity and mortality. This study aims to develop a practical and efficient prognostic index for early identification and possible prediction of post-transplant infections using risk factors identified by multivariate analysis.

MATERIAL AND METHODS

One hundred patients with post-hepatitic cirrhosis, HCV positive, genotype 4, Child B/C or MELD score 13-25 undergoing LDLT were included. All potential predictors of infection were analyzed by backward logistic regression. Cut-off values were obtained from ROC curve analysis. Significant predictors were combined into a risk index, which was further tested and compared by ROC curve analysis.

RESULTS

Post-operative infection was associated with a significantly higher mortality (50.7% vs. 33.3%). Total leucocyte count, total bilirubin, early biliary complications, fever and C-reactive protein were found to be independent predictors of early infectious complications after LDLT. The risk index predicted infection with the highest sensitivity and specificity as compared with each predictor on its own (AUC = 0.91, 95% CI: 0.830-0.955, p < 0.0001).

CONCLUSIONS

The use of a combined risk index for early diagnosis of post-operative infections can efficiently identify high risk patients.

Dermatological Disorders following Liver Transplantation: An Update

Patients undergoing liver transplantation (LT) are at a high risk of dermatological complications compared to the general population as a result of long-term use of immunosuppressant. However, the risk is not as high as other solid organ transplantations (SOT), particularly for skin cancer. The liver is considered as an immune privileged organ since it has a low prevalence of humoral rejection in contrast to other SOT, and thus, LT requires a minimal amount of immunosuppressants compared to other SOT recipients. However, because of the large volume of the liver, patients with LT have higher donor lymphocytes that sometimes may trigger graft-versus-host-disease, yet it is rare. On the other hand, the vast majority of the nonspecific dermatological lesions linked with cirrhosis improve after removal of diseased liver or due to the immunosuppressant used after LT. Nevertheless, dermatological infections related to bacteria, viruses, and fungus after LT are not uncommon. Additionally, the incidence of IgE-mediated food allergies develops in 12.2% of LT patients and may present as life-threatening conditions such as urticaria and/or angioedema and hypersensitivity. Moreover, skin malignancies after LT are a matter of concern. Thus, posttransplant dermatological care should be provided to all LT patients for any suspicious dermatological lesions. Our goal is to give an outline of the dermatological manifestation associated with LT for the clinicians by collecting the published data from all archived case reports.

Association between viscoelastic tests-guided therapy with synthetic factor concentrates and allogenic blood transfusion in liver transplantation: a before-after study

Background

Perioperative bleeding and transfusion are important causes of morbidity and mortality in patients undergoing liver transplantation. The aim of this study is to assess whether viscoelastic tests-guided therapy with the use of synthetic factor concentrates impact transfusion rates of hemocomponents in adult patients undergoing liver transplantation.

Methods

This is an interventional before-after comparative study. Patients undergoing liver transplantation before the implementation of a protocol using thromboelastometry and synthetic factor concentrates were compared to patients after the implementation. Primary outcome was transfusion of any hemocomponents. Secondary outcomes included: transfusion of red blood cells (RBC), fresh frozen plasma (FFP), cryoprecipitate or platelets, clinical complications, length of stay and in-hospital mortality.

Results

A total of 183 patients were included in the control and 54 in the intervention phase. After propensity score matching, the proportion of patients receiving any transfusion of hemocomponents was lower in the intervention phase (37.0 vs 58.4%; OR, 0.42; 95% CI, 0.20–0.87; p = 0.019). Patients in the intervention phase received less RBC (30.2 vs 52.5%; OR, 0.21; 95% CI, 0.08–0.56; p = 0.002) and FFP (5.7 vs 27.3%; OR, 0.11; 95% CI, 0.03–0.43; p = 0.002). There was no difference regarding transfusion of cryoprecipitate and platelets, complications related to the procedure, hospital length of stay and mortality.

Conclusions

Use of a viscoelastic test-guided transfusion algorithm with the use of synthetic factor concentrates reduces the transfusion rates of allogenic blood in patients submitted to liver transplantation.

Trial registration

This trial was registered retrospectively on November 15th, 2018 – clinicaltrials.gov – Identifier: NCT03756948.

Electronic supplementary material

The online version of this article (10.1186/s12871-018-0664-8) contains supplementary material, which is available to authorized users.

Aspergillus pseudodeflectus: a new human pathogen in liver transplant patients

BACKGROUND

Liver transplant recipients are at high risk of developing invasive aspergillosis and in particular by Aspergillus fumigatus which is the most commonly encountered species in this population. Other non-fumigatus Aspergillus species with reduced susceptibility to antifungal drugs can also be involved. Accurate identification associated to antifungal susceptibility testing is essential for therapy adjustment. We report a case of invasive pulmonary aspergillosis due to Aspergillus pseudodeflectus in a liver transplant recipient. To our knowledge, this is the first reported case of invasive aspergillosis due to this species with a reduced susceptibility to azoles.

CASE PRESENTATION

A 64 year-old woman with drug-induced fulminant hepatitis underwent liver transplantation. Prophylactic treatment with caspofungin was introduced due to aspergillosis risk factors consisting in hemodialysis and fulminant hepatitis. Six weeks after transplantation, CT scan showed a right pulmonary opacity associated with an increase of galactomannan (index 5.4). Culture of BAL grew with several colonies of Aspergillus sp. The diagnosis of invasive aspergillosis was probable according to the EORTC criteria. The antifungal susceptibility tests (Etest®) revealed low MICs to echinocandins and amphotericin B) but high MICs to azoles. After these results, voriconazole was switched to liposomal amphotericin B. The patient died one month after diagnosis from a refractory septic shock with multiple organ failure. A molecular identification of isolate, based on partial β-tubulin and calmodulin genes, was performed and identified A. pseudodeflectus.

CONCLUSIONS

Our case raises the question of pathogenicity of this species, which belongs to Aspergillus section Usti and is genetically and morphologically very close to Aspergillus calidoustus that was previously reported in human transplant recipients.

Management of bacterial and fungal infections in end stage liver disease and liver transplantation: Current options and future directions

Patients with liver cirrhosis are susceptible to infections due to various mechanisms, including abnormalities of humoral and cell-mediated immunity and occurrence of bacterial translocation from the intestine. Bacterial infections are common and represent a reason for progression to liver failure and increased mortality. Fungal infections, mainly caused by Candida spp., are often associated to delayed diagnosis and high mortality rates. High level of suspicion along with prompt diagnosis and treatment of infections are warranted. Bacterial and fungal infections negatively affect the outcomes of liver transplant candidates and recipients, causing disease progression among patients on the waiting list and increasing mortality, especially in the early post-transplant period. Abdominal, biliary tract, and bloodstream infections caused by Gram-negative bacteria [e.g., Enterobacteriaceae and Pseudomonas aeruginosa (P. aeruginosa)] and Staphylococcus spp. are commonly encountered in liver transplant recipients. Due to frequent exposure to broad-spectrum antibiotics, invasive procedures, and prolonged hospitalizations, these patients are especially at risk of developing infections caused by multidrug resistant bacteria. The increase in antimicrobial resistance hampers the choice of an adequate empiric therapy and warrants the knowledge of the local microbial epidemiology and the implementation of infection control measures. The main characteristics and the management of bacterial and fungal infections in patients with liver cirrhosis and liver transplant recipients are presented.

Early Postoperative Infections After Liver Transplant

OBJECTIVES

Despite surgical advances and effective prophylactic strategies in liver transplant, infection is still a major cause of morbidity and mortality. Up to 80% of liver recipients will develop at least 1 infection during the first year after liver transplant. The spectrum and manifestations of these infections are broad and variable. Their diagnosis and treatment are often delayed because immunosuppressive therapy diminishes inflammatory responses. However, if an infection is not identified early enough and treated properly, it can have devastating consequences. In addition, prophylactic approaches remain controversial. Our aim was to review our early postoperative infection management after liver transplant.

MATERIALS AND METHODS

We retrospectively evaluated infections that occurred during the first hospital stay of transplant patients. Infections were grouped as surgical site and nonsurgical site infections. Consequences and treatment protocols of infections were stratified according to the Clavien scale.

RESULTS

Between December 1988 and January 2017, we performed 561 liver transplants at our center (patient age range, 6 months to 64 years), which included 401 living-donor (72%) and 160 deceaseddonor (28%) liver transplants. Early postoperative infections were detected in 131 patients (23.3%), comprising 67 surgical site (51%), 56 nonsurgical site (43%), and 8 combined surgical and nonsurgical site infections (6%). Although no mortalities occurred in patients with single nonsurgical or surgical site infections, there were 4 mortalities in patients with combined surgical and nonsurgical site infections. In the 4 other patients with combined infections, 3 patients required endoscopic or radiologic intervention and 1 recovered from single-organ dysfunction.

CONCLUSIONS

Initiation of appropriate prophylactic and therapeutic protocols at the right time decreases morbidity and mortality due to infection in liver transplant recipients. Increased understanding and effective approaches to prevent infection are essential to improving both graft and recipient survival.

Key roles of hepatologists in successful liver transplantation

Liver transplantation (LT) has been carried out for acute liver failure, end-stage liver disease, and congenital metabolic disease in more than 7000 cases in Japan. Liver transplantation has been established as a treatment option, and survival rates have improved. In 2016, a new registration/allocation policy and a new scoring system for deceased donor LT were established. The management of perioperative patients and preoperative therapy for liver failure, nutrition, and preventing infection were upgraded. Moreover, methods for preventing disease recurrence, and treating hepatitis C and B have been developed and are particularly crucial for good outcomes in LT. Treatment of the complications of obesity, lifestyle-related diseases, and malignancy is also required post-LT. Managing patients after LT contributes to better survival and quality of life. The role of hepatologists is becoming broader and more important.

Risk factors and outcomes of pyogenic liver abscess in adult liver recipients: a matched case-control study

BACKGROUND

Adult liver recipients (ALR) differ from the general population with pyogenic liver abscess (PLA) as they exhibit: reconstructed biliary anatomy, recurrent hospitalizations, poor clinical condition and are subjected to immunosuppression. The aim of this study was to identify risk factors associated with PLA in ALR and to analyze the management experience of these patients.

METHODS

Between 1996 and 2016, 879 adult patients underwent liver transplantation (LT), 26 of whom developed PLA. Patients and controls were matched according to the time from transplant to abscess in a 1 to 5 relation. A logistic regression model was performed to establish PLA risk factors considering clusters for matched cases and controls. Risk factors were identified and a multivariate regression analysis performed.

RESULTS

Patients with post-LT PLA were more likely to have lower BMI (p = 0.006), renal failure (p = 0.031) and to have undergone retransplantation (p = 0.002). A history of hepatic artery thrombosis (p = 0.010), the presence of Roux en-Y hepatojejunostomy (p < 0.001) and longer organ ischemia time (p = 0.009) were independent predictors for the development of post-LT PLA. Five-year survival was 49% (95%CI 28-67%) and 89% (95%CI 78%-94%) for post-LT PLA and no post-LT PLA, respectively (p < 0.001).

CONCLUSION

history of hepatic artery thrombosis, the presence of hepatojejunostomy and a longer ischemia time represent independent predictors for the development of post-LT PLA. There was a significantly poorer survival in patients who developed post-LT PLA compared with those who did not.

Cytomegalovirus infection in living donor liver transplant recipients significantly impacts the early post-transplant outcome: A single center experience

BACKGROUND

Cytomegalovirus (CMV) is the most common viral infection in liver transplant recipients that influences the outcomes of liver transplantation. However, its impact on early outcomes following living donor liver transplantation (LDLT) is not fully defined in the Indian subcontinent. This study was done to assess the impact of CMV infection on early post-transplant outcomes in LDLT recipients.

METHODS

Out of 272 LDLTs performed from January 2012 to April 2013, 151 recipients underwent CMV viral load analysis in plasma within 90 days post LDLT based on clinical suspicion. Patients with CMV infection (n = 55) were compared with those without CMV infection (n = 96).

RESULTS

The median time interval of CMV infection from LDLT was 25 days (range 2-90 days). The mean age of study population was 48.92 years. About 116 (76.8%) of the patients were male. Hepatitis C virus (HCV) (39.1%)-related chronic liver disease (CLD) was most common indication for liver transplant. No statistically significant difference was observed in etiology of liver disease (P = .38), Chid-Turcotte-Pugh (CTP) (P = .41), and Model for End-stage Liver Disease (MELD) (P = .12) scores between the groups. Patients with CMV infection had significantly higher incidence of acute cellular rejection (16.1% vs 5.4%, P = .02); longer ICU stay (P = .01); and a higher overall 90-day mortality (24.2% vs 6.7%, P = .001). Bacteremia and fungemia were significantly more common in the CMV infection group.

CONCLUSION

Cytomegalovirus infection significantly influences the early post LDLT outcomes and contributes to increased overall mortality.