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

The impact of colonization by multidrug resistant bacteria on graft survival, risk of infection, and mortality in recipients of solid organ transplant: systematic review and meta-analysis

BACKGROUND

The Global increase in colonization by multidrug-resistant (MDR) bacteria poses a significant concern. The precise impact of MDR colonization in solid organ transplant recipients (SOTR) remains not well established.

OBJECTIVES

To assess the impact of MDR colonization on SOTR's mortality, infection, or graft loss.

METHODS AND DATA SOURCES

Data from PROSPERO, OVID Medline, OVID EMBASE, Wiley Cochrane Library, ProQuest Dissertations, Theses Global, and SCOPUS were systematically reviewed, spanning from inception until 20 March 2023. The study protocol was registered with PROSPERO (CRD42022290011) and followed the PRISMA guidelines. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, INTERVENTIONS, AND ASSESSMENT OF RISK OF BIAS: Cohorts and case-control studies that reported on adult SOTR colonized by Methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), extended-spectrum β-lactamase (ESBL) or carbapenem-resistant Enterobacteriaceae. (CRE), or MDR-pseudomonas, and compared to noncolonized, were included. Two reviewers assessed eligibility, conducted a risk of bias evaluation using the Newcastle-Ottawa Scale, and rated certainty of evidence using the GRADE approach.

METHODS OF DATA SYNTHESIS

We employed RevMan for a meta-analysis, using random-effects models to compute pooled odds ratios (OR) and 95% confidence intervals (CI). Statistical heterogeneity was determined using the I2 statistic.

RESULTS

15,202 SOTR (33 cohort, six case-control studies) were included, where liver transplant and VRE colonization (25 and 14 studies) were predominant. MDR colonization significantly increased posttransplant 1-year mortality (OR, 2.35; 95% CI, 1.63-3.38) and mixed infections (OR, 10.74; 95% CI, 7.56-12.26) across transplant types (p < 0.001 and I2 = 58%), but no detected impact on graft loss (p 0.41, I2 = 0). Subgroup analysis indicated a higher association between CRE or ESBL colonization with outcomes (CRE: death OR, 3.94; mixed infections OR, 24.8; ESBL: mixed infections OR, 10.3; no mortality data) compared to MRSA (Death: OR, 2.25; mixed infection: OR, 7.75) or VRE colonization (Death: p 0.20, mixed infections: OR, 5.71).

CONCLUSIONS

MDR colonization in SOTR, particularly CRE, is associated with increased mortality. Despite the low certainty of the evidence, actions to prevent MDR colonization in transplant candidates are warranted.

Expert consensus on the diagnosis and treatment of end-stage liver disease complicated by infections

End-stage liver disease (ESLD) is a life-threatening clinical syndrome and when complicated with infection the mortality is markedly increased. In patients with ESLD, bacterial or fungal infection can induce or aggravate the occurrence or progression of liver decompensation. Consequently, infections are among the most common complications of disease deterioration. There is an overwhelming need for standardized protocols for early diagnosis and appropriate management for patients with ESLD complicated by infections. Asia Pacific region has the largest number of ESLD patients, due to hepatitis B and the growing population of alcohol and NAFLD. Concomitant infections not only add to organ failure and high mortality but also to financial and healthcare burdens. This consensus document assembled up-to-date knowledge and experience from colleagues across the Asia-Pacific region, providing data on the principles as well as evidence-based current working protocols and practices for the diagnosis and treatment of patients with ESLD complicated by infections.

Comparative phenotypic and genotypic analysis of community-acquired and hospital-acquired intra-abdominal infections among liver transplanted patients

AIM

During liver transplantation, both hospital-acquired (HA) and community-acquired (CA) intra-abdominal infections (IAIs) are involved causing life-threatening diseases. Therefore, comparative studies of aerobic and facultative anaerobic HA-IAIs and CA-IAIs after liver transplantation surgery are necessary.

METHODS AND RESULTS

The species of detected isolates (310) from intra-abdominal fluid were identified and classified into hospital-acquired intra-abdominal infections (HA-IAIs) and community-acquired intra-abdominal infections (CA-IAIs). Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii were the most commonly detected species. The resistant phenotypes were commonly detected among the HA-IAIs; however, the virulent phenotypes were the predominant strains of CA-IAIs. Regrettably, the resistance profiles were shocking, indicating the inefficacy of monotherapy in treating these isolates. Therefore, we confirmed the use of empirical combination therapies of amikacin and meropenem for treating all IAIs (FICI ≤ 0.5). Unfortunately, the high diversity and low clonality of all identified HA and CA-IAIs were announced with D-value in the range of 0.992-1.

CONCLUSION

This diversity proves that there are infinite numbers of infection sources inside and outside healthcare centers.

Bacterial Infections After Liver Transplantation and the Role of Oral Selective Digestive Decontamination: A Retrospective Cohort Study

BACKGROUND

Bacterial infections are common after liver transplantation (LT) and cause serious morbidity and mortality. In our center, prolonged selective digestive decontamination (SDD) is the standard of care, which may lead to a reduced number and severity of bacterial infections. The aim of the current study was to investigate bacterial infection rates, the causative pathogens, localization, and the possible influence of SDD within the first year after LT.

METHODS

A retrospective single-center cohort study was performed. Patients within their first year after LT between 2012 and 2017 were included. Patients received SDD for 3 weeks immediately after LT. The type of infection, bacterial subtype, CSI classification, severity, and potential interventions were recorded.

RESULTS

One hundred eighty-six patients were included in the study. Seventy-eight patients (41.9%) had a bacterial infection within the first year after LT. The most common types of infection were cholangitis (25.8%) and secondary infected abdominal fluid collections (25.3%). The most common bacteria were Gram-positive enterococcal- (36.5%) and Gram-negative enterobacterial species (34.2%). 35.5% of the infections occurred within the first month after LT, mainly caused by Gram-positive bacteria (76.7%).

CONCLUSIONS

Cholangitis and infected abdominal fluid are the most common types of infection within one year after LT, mainly caused by enterococcal- and enterobacterial species. Within the first month after LT, infections were mostly caused by Gram-positive bacteria, which could be a consequence of protocol use of SDD. The results can be used for the choice of empirical antibiotic therapy based on the most common types of bacteria and the time frame after LT.

Role of the immune system in liver transplantation and its implications for therapeutic interventions

Liver transplantation (LT) stands as the gold standard for treating end-stage liver disease and hepatocellular carcinoma, yet postoperative complications continue to impact survival rates. The liver's unique immune system, governed by a microenvironment of diverse immune cells, is disrupted during processes like ischemia-reperfusion injury posttransplantation, leading to immune imbalance, inflammation, and subsequent complications. In the posttransplantation period, immune cells within the liver collaboratively foster a tolerant environment, crucial for immune tolerance and liver regeneration. While clinical trials exploring cell therapy for LT complications exist, a comprehensive summary is lacking. This review provides an insight into the intricacies of the liver's immune microenvironment, with a specific focus on macrophages and T cells as primary immune players. Delving into the immunological dynamics at different stages of LT, we explore the disruptions after LT and subsequent immune responses. Focusing on immune cell targeting for treating liver transplant complications, we provide a comprehensive summary of ongoing clinical trials in this domain, especially cell therapies. Furthermore, we offer innovative treatment strategies that leverage the opportunities and prospects identified in the therapeutic landscape. This review seeks to advance our understanding of LT immunology and steer the development of precise therapies for postoperative complications.

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: The Early Killer after Liver Transplantation

BACKGROUND

Liver transplantation is a standard of care and a life-saving procedure for end-stage liver diseases and certain malignancies. The evidence on predictors and risk factors for poor outcomes is lacking. Therefore, we aimed to identify potential risk factors for mortality and to report on overall 90-day mortality after orthotopic liver transplantation (OLT), especially focusing on the role of fungal infections.

METHODS

We retrospectively reviewed medical charts of all patients undergoing OLT at a tertiary university center in Europe.

RESULTS

From 299 patients, 214 adult patients who received a first-time OLT were included. The OLT indication was mainly due to tumors (42%, 89/214) and cirrhosis (32%, 68/214), including acute liver failure in 4.7% (10/214) of patients. In total, 8% (17/214) of patients died within the first three months, with a median time to death of 15 (1-80) days. Despite a targeted antimycotic prophylaxis using echinocandins, invasive fungal infections occurred in 12% (26/214) of the patients. In the multivariate analysis, patients with invasive fungal infections had an almost five times higher chance of death (HR 4.6, 95% CI 1.1-18.8; p = 0.032).

CONCLUSIONS

Short-term mortality after OLT is mainly determined by infectious and procedural complications. Fungal breakthrough infections are becoming a growing concern. Procedural, host, and fungal factors can contribute to a failure of prophylaxis. Finally, invasive fungal infections may be a potentially modifiable risk factor, but the ideal perioperative antimycotic prophylaxis has yet to be determined.

Characteristics of Gram-positive cocci infection and the therapeutic effect after liver transplantation

OBJECTIVES

Gram-positive cocci is the main pathogen responsible for early infection after liver transplantation (LT), posing a huge threat to the prognosis of liver transplant recipients. This study aims to analyze the distribution and drug resistance of Gram-positive cocci, the risk factors for infections and efficacy of antibiotics within 2 months after LT, and to guide the prevention and treatment of these infections.

METHODS

In this study, data of pathogenic bacteria distribution, drug resistance and therapeutic efficacy were collected from 39 Gram-positive cocci infections among 256 patients who received liver transplantation from donation after citizens' death in the Third Xiangya Hospital of Central South University from January 2019 to July 2022, and risk factors for Gram-positive cocci infection were analyzed.

RESULTS

Enterococcus faecium was the dominant pathogenic bacteria (33/51, 64.7%), followed by Enterococcus faecalis (11/51, 21.6%). The most common sites of infection were abdominal cavity/biliary tract (13/256, 5.1%) and urinary tract (10/256, 3.9%). Fifty (98%) of the 51 Gram-positive cocci infections occurred within 1 month after LT. The most sensitive drugs to Gram-positive cocci were teicoplanin, tigecycline, linezolid and vancomycin. Vancomycin was not used in all patients, considering its nephrotoxicity. Vancomycin was not administered to all patients in view of its nephrotoxicity.There was no significant difference between the efficacy of daptomycin and teicoplanin in the prevention of cocci infection (P>0.05). Univariate analysis indicated that preoperative Model for End-Stage Liver Disease (MELD) score >25 (P=0.005), intraoperative red blood cell infusion ≥12 U (P=0.013) and exposure to more than 2 intravenous antibiotics post-LT (P=0.003) were related to Gram-positive cocci infections. Multivariate logistic regression analysis revealed that preoperative MELD score >25 (OR=2.378, 95% CI 1.124 to 5.032, P=0.024) and intraoperative red blood cell transfusion ≥ 12 U (OR=2.757, 95% CI 1.227 to 6.195, P=0.014) were independent risk factors for Gram-positive cocci infections after LT. Postoperative Gram-positive cocci infections were reduced in LT recipients exposing to more than two intravenous antibiotics post-LT (OR=0.269, 95% CI 0.121 to 0.598, P=0.001).

CONCLUSIONS

Gram-positive cocci infections occurring early after liver transplantation were dominated by Enterococcus faecalis infections at the abdominal/biliary tract and urinary tract. Teicoplanin, tigecycline and linezolid were anti-cocci sensitive drugs. Daptomycin and teicoplanin were equally effective in preventing cocci infections due to Gram-positive cocci. Patients with high preoperative MELD score and massive intraoperative red blood cell transfusion were more likely to suffer Gram-positive cocci infection after surgery. Postoperative Gram-positive cocci infections were reduced in recipients exposing to more than two intravenous antibiotics post-LT.

Clinical Characteristics and Early Diagnosis of Spontaneous Fungal Peritonitis/Fungiascites in Hospitalized Cirrhotic Patients with Ascites: A Case-Control Study

BACKGROUND

Spontaneous fungal peritonitis (SFP) and fungiascites is less well-recognized and described in patients with liver cirrhosis. The aims of this study were to determine the clinical characteristics, prognosis, and risk factors of cirrhotic patients with SFP/fungiascites and to improve early differential diagnosis with spontaneous bacterial peritonitis (SBP).

METHODS

This was a retrospective case-control study of 54 cases of spontaneous peritonitis in cirrhotic patients (52 SFP and 2 fungiascites) with fungus-positive ascitic culture. Fifty-four SBP cirrhotic patients with bacteria-positive ascitic culture were randomly enrolled as a control group. A nomogram was developed for the early differential diagnosis of SFP and fungiascites.

RESULTS

Hospital-acquired infection was the main cause of SFP/fungiascites. Of the 54 SFP/fungiascites patients, 31 (57.41%) patients carried on with the antifungal treatment, which seemed to improve short-term (30-days) mortality but not long-term mortality. Septic shock and HCC were independent predictors of high 30-day mortality in SFP/fungiascites patients. We constructed a predictive nomogram model that included AKI/HRS, fever, (1,3)-β-D-glucan, and hospital-acquired infection markers for early differential diagnosis of SFP/fungiascites in cirrhotic patients with ascites from SBP, and the diagnostic performance was favorable, with an AUC of 0.930 (95% CI: 0.874-0.985).

CONCLUSIONS

SFP/fungiascites was associated with high mortality. The nomogram established in this article is a useful tool for identifying SFP/fungiascites in SBP patients early. For patients with strongly suspected or confirmed SFP/fungiascites, timely antifungal therapy should be administered.

Fungal infections and the fungal microbiome in hepatobiliary disorders

Liver and biliary diseases affect more than a billion people worldwide, with high associated morbidity and mortality. The impact of the intestinal bacterial microbiome on liver diseases has been well established. However, the fungal microbiome, or mycobiome, has been overlooked for a long time. Recently, several studies have shed light on the role of the mycobiome in the development and progression of hepatobiliary diseases. In particular, the fungal genus Candida has been found to be involved in the pathogenesis of multiple hepatobiliary conditions. Herein, we compare colonisation and infection, describe mycobiome findings in the healthy state and across the various hepatobiliary conditions, and point toward communalities. We detail how quantitation of immune responses to fungal antigens can be employed to predict disease severity, e.g. using antibodies to Saccharomyces cerevisiae or specific anti-Candida albicans antibodies. We also show how fungal products (e.g. beta-glucans, candidalysin) activate the host's immune system to exacerbate liver and biliary diseases. Finally, we describe how the gut mycobiome can be modulated to ameliorate hepatobiliary conditions.

Long-term Care of the Adult Liver Transplant Recipient

While outcomes after liver transplantation have increased over the last two decades, this is primarily as a consequence of a reduction in early deaths and survival of those who survive the first 6 months has not significantly changed. Causes of premature death and graft loss include cardiovascular disease, renal impairment, malignancy and some infections. As the number of transplant recipients increase, care is being given by primary and secondary care clinicians. Management of the well patient is crucially dependent on careful assessment and where appropriate intervention, especially of cardiovascular risk - such as advice about avoidance of weight gain; management of hypertension, hyperlipidaemia and diabetes; and provision of appropriate lifestyle advice. Other interventions include surveillance for de novo malignancies, active management of immunosuppressive regimen with the need to tailor immunosuppression to the individual. Prompt investigation of abnormalities of liver function is essential. Immune-mediated graft damage still occurs but is less common as a cause for graft loss. Adherence is sometimes an issue, especially in teenagers and young adults, and should be considered and support given where needed. Immunisations (avoiding live and attenuated vaccines) should be encouraged. Recurrence of disease remains an issue, and some interventions (such as appropriate use of antiviral therapy for those grafted with viral hepatitis, use of ursodeoxycholic acid for those grafted for primary biliary cholangitis or long-term steroids for those grafted for autoimmune disease) may improve and maintain graft function. Close collaboration between recipient and the attending clinicians in primary, secondary and tertiary care and close attention to modifiable conditions will lead to improved outcomes.

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.

Management of Multidrug-Resistant Infections in Cirrhosis

The World Health Organization describes antimicrobial resistance as one of the biggest threats to global health, food security, and development with indiscriminate use of antimicrobials globally driving the emergence of multidrug-resistant bacteria, resistant to 60% of antimicrobials in some countries. Infections with multidrug-resistant organisms (MDROs) have increased in recent decades in patients with cirrhosis, who are frequently prescribed antibiotics, regularly undergo invasive procedures such as large volume paracentesis, and have recurrent hospitalizations, posing a particular risk in this already immunocompromised cohort of patients. In this review, we explore mechanisms underlying this vulnerability to MDRO infection; the effect of bacterial infections on disease course in cirrhosis; prevalence of MDROs in patients with cirrhosis; outcomes following MDRO infection; fungal infections; antibiotics and their efficacy; and management of MDRO infections in terms of detection, antimicrobial and nonantimicrobial treatments, prophylaxis, antibiotic stewardship, the gut microbiome, and technological interventions.

Candidemia in hospitalized cirrhotic patients with bloodstream infection: A retrospective analysis and brief summary of published studies

BACKGROUND

Candidemia is a life-threatening condition; however, the predictive markers for candidemia and mortality are inadequate in cirrhotic patients. This study was conducted to propose candidate predictors for the occurrence of candidemia and 30-day mortality in hospitalized cirrhotic patients with bloodstream infection (BSI) and review the related literature.

METHODS

Cirrhotic patients with BSI between January 2011 and March 2020 were screened from the databank of a medical center and eligible patients were enrolled. Patients were separated into candidemia and bacteremia groups according to the results of blood cultures. Baseline characteristics, clinical presentation, and biochemistry data were collected at this time, as were microbiological data, medical management, use of antimicrobial agents, and outcome of the patients. The parameters and 30-day mortality were compared between candidemia and bacteremia groups. A combination of the MeSH terms and text terms related to candidemia and cirrhosis was searched in the electronic databases.

RESULTS

Four hundred and sixty cirrhotic patients with BSI were enrolled. Thirty-five patients with candidemia (7.6%) were identified. Nosocomial infection, intensive care unit (ICU) admission, antibiotics exposure ≥14 days, white cell count >10 K/mm3, and model for end-stage liver disease (MELD) score >24 were associated with candidemia. The 30-day mortality was 65.7% in the candidemia group and 37.9% in the bacteremia group (p = 0.001). Nosocomial infection, ICU admission, hepatoma, hepatic encephalopathy, international normalized ratio ≥1.2, platelet ≤150 K/mm3, estimated glomerular filtration rate <60 mL/min/1.73m2, and MELD score >24 were associated with 30-day mortality. Six studies were identified. The results were consistent with our findings regarding low incidence of candidemia, and relevant risk factors are listed.

CONCLUSION

Candidemia had low incidence but high mortality in hospitalized cirrhotic patients with BSI. New predictors were proposed for the occurrence of candidemia and 30-day mortality in these patients.

Eurobusones A-D, four antibacterial formyl phloroglucinol meoterpenoids from Eucalyptus robusta

Four antibacterial formyl phloroglucinol meroterpenoids (FPMs), eurobusones A-D (1-4), as well as six known analogues (5-10), were isolated from the leaves of Eucalyptus robusta. Their structures were determined by the analysis of spectroscopic data and electron circular dichroism (ECD) calculation, along with the application of Snatzke helicity rules. Among them, compounds 2 and 8-10 showed good activity against Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus subtilis with MIC₅₀ values less than 1.00 μg/mL.

Adult stem cell transplantation combined with conventional therapy for the treatment of end-stage liver disease: a systematic review and meta-analysis

End-stage liver disease (ESLD) is characterized by the deterioration of liver function and a subsequent high mortality rate. Studies have investigated the use of adult stem cells to treat ESLD. Here, a systematic review and meta-analysis was conducted to determine the efficacy of a combination therapy with adult stem cell transplantation and traditional medicine for treating ESLD. Four databases-including PubMed, Web of Science, Embase, and Cochrane Library-were investigated for studies published before January 31, 2021. The main outcome indicators were liver function index, model for end-stage liver disease (MELD) scores, and Child‒Turcotte‒Pugh (CTP) scores. Altogether, 1604 articles were retrieved, of which eight met the eligibility criteria; these studies included data for 579 patients with ESLD. Combination of adult stem cell transplantation with conventional medicine significantly improved its efficacy with respect to liver function index, CTP and MELD scores, but this effect gradually decreased over time. Moreover, a single injection of stem cells was more effective than two injections with respect to MELD and CTP scores and total bilirubin (TBIL) and albumin (ALB) levels, with no significant difference in aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. With respect to the TBIL levels, patients receiving mononuclear cells (MNCs) experienced a significantly greater therapeutic effect-starting from twenty-four weeks after the treatment-whereas with respect to ALB levels, CD34⁺ autologous peripheral blood stem cells (CD34⁺ APBSCs) and MNCs had similar therapeutic effects. Severe complications associated with adult stem cell treatment were not observed. Although the benefits of combination therapy with respect to improving liver function were slightly better than those of the traditional treatment alone, they gradually decreased over time.Systematic review registration: PROSPERO registration number: CRD42021238576.

Candida tropicalis cellulitis in a patient with cirrhosis, well-controlled HIV and diabetes

We present the case of a patient with multiple comorbidities, including cirrhosis, poorly controlled diabetes mellitus and HIV infection, who was diagnosed with skin and soft-tissue infection of right lower limb. Outcome was poor after prescribing standard antibiotic therapy, and we finally obtained isolation of Candida tropicalis in cultures of infected tissue. The patient's condition improved after antifungal treatment was started, and he could be discharged with oral therapy. Here, we report the literature's first case of cellulitis provoked by C. tropicalis in a patient with cirrhosis.

Successful, Combined Long-term Treatment of Cerebral Candidiasis and Aspergillosis in a Liver Transplant Recipient: A Case Report

Invasive fungal infections, of which the most common are candidiasis and aspergillosis, are among the most important and fatal complications in solid organ transplantation. They continue to be a significant cause of morbidity and mortality in patients with involvement of the central nervous system (CNS) because of the poor CNS penetration of antifungal medications. Voriconazole yields fungicidal drug concentrations in the CNS, but its use is limited in solid organ transplant patients because of its metabolic interactions with immunosuppression. Here we report a case of invasive fungal infection in the CNS after an emergency liver transplantation due to hepatitis B virus-related acute liver failure. The patient was managed successfully with a long-term conservative medical treatment.

Fungal liver infection mimicking hepatic malignant tumor on contrast enhanced ultrasound: A case report

RATIONAL

Fungal liver infection mostly occurs in immunocompromised patients, and is often associated with delayed diagnosis and high mortality rates. Dynamic contrast enhanced imaging is crucial for the diagnosis of fungal liver infection and has been reported having variable manifestations.

PATIENT CONCERNS

A 38-year-old Chinese man, with a history of diabetes and chronic hepatitis B, was admitted to our hospital due to prolonged fever of unknown cause. He had a medical history of receiving broad-spectrum antibiotic treatment for pulmonary inflammation at the local hospital. The blood test results showed that the white cell count (14.0 × 109/L) and neutrophil count ratio (77.0%) were subtly elevated. C-reactive protein (92.0 mg/l) and cancer antigen (CA)-125 (904.50 U/ml) were elevated. Non-small cell lung cancer antigen was within the normal limit. Hepatitis B virus DNA load was 3.28 × 103 IU/ml. Sputum and blood cultures were normal. Abdominal ultrasonography (US) found a large heterogeneous mass, with diffused echogenic foci without infiltrating the surrounding vascular, which exhibiting "rapid wash in and out" on contrast-enhanced ultrasound (CEUS).

DIAGNOSIS

The diagnosis of liver fungal infection was confirmed pathologically via ultrasound-guided biopsy.

INTERVENTIONS

Antibiotic and antifungal therapy with imipenem and voriconazole.

OUTCOMES

The patient's body temperature had been controlled and the huge mass disappeared on follow-up ultrasound 1-year later.

LESSONS

This case highlights the unusual imaging features of fungal liver infection, presenting as huge heterogeneous mass with diffusive echogenic foci without infiltrating the surrounding vascular on grayscale US and the enhancement pattern of "rapid wash in and out" on CEUS. Additionally, ultrasound-guided biopsy is necessary for the correct diagnosis of suspected liver lesions.

Clinical Outcome of Vancomycin-Resistant Enterococcus Colonization Among Liver Transplant Recipients at Shiraz Organ Transplant Center

OBJECTIVES

Liver transplant recipients are more susceptible to vancomycin-resistant enterococci colonization than healthy individuals. We investigated the prevalence of vancomycin-resistant enterococci colonization and its effect on the outcomes of liver transplant recipients.

MATERIALS AND METHODS

Patients who had undergone primary liver transplant at the Shiraz Organ Transplant Center from 2015 to 2017 were enrolled in this study. Demographic characteristics, laboratory test results, duration of stay in the intensive care unit, total duration of hospital stay, and clinical outcome data were extracted from the Shiraz Organ Transplant Center database. Posttransplant outcomes such as graft rejection, mortality, hospital stay, and kidney function tests were included for the first 90 days after transplant.

RESULTS

A total of 753 liver transplant recipients (470 males and 283 females) were included in this study. Vancomycin-resistant enterococci colonization was identified in 51 patients (6.8%) after transplant at the time of intensive care unit admission. Our study found no significant difference between outcomes for patients with vancomycin-resistant enterococci colonization and outcomes for patients without colonization, including graft rejection, mortality, hospital stay, and kidney function tests.

CONCLUSIONS

Our study revealed that asymptomatic vancomycin-resistant enterococci colonization in liver transplant patients has no adverse effect on the duration of posttransplant hospital stay, early mortality rate, graft rejection rate, or kidney function compared with noncolonized patients.

Risk Factors and Impact of Perioperative Prophylaxis on the Risk of Extended-spectrum β-Lactamase-producing Enterobacteriaceae-related Infection Among Carriers Following Liver Transplantation

BACKGROUND

Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) carriage is frequent among liver transplant (LT) recipients, thereby fostering a large empirical carbapenem prescription. However, ESBL-E infections occur in only 10%-25% of critically ill patients with rectal colonization. Our aim was to identify risk factors for post-LT ESBL-E infection in colonized patients. The effect of perioperative antimicrobial prophylaxis (AP) was also analyzed in patients with prophylaxis lasting <48 hours and without proven intraoperative infection.

METHODS

Retrospective study from a prospective database including patients with a positive ESBL-E rectal screening transplanted between 2010 and 2016.

RESULTS

Among the 749 patients transplanted, 100 (13.3%) were colonized with an ESBL-E strain. Thirty-nine (39%) patients developed an infection related to the same ESBL-E (10 pulmonary, 11 surgical site, 13 urinary, 5 bloodstream) within 11 postoperative days in median. Klebsiella pneumoniae carriage, model for end-stage liver disease ≥25, preoperative spontaneous bacterial peritonitis prophylaxis, and antimicrobial exposure during the previous month were independent predictors of ESBL-E infection. We propose a colonization to infection risk score built on these variables. The prevalence of infection for colonization to infection score of 0, 1, 2, and ≥3 were 7.4%, 26.3%, 61.9%, and 91.3%, respectively. Of note, the incidence of post-LT ESBL-E infection was lower in case of perioperative AP targeting colonizing ESBL-E (P = 0.04).

CONCLUSIONS

Thirty-nine percentage of ESBL-E carriers develop a related infection after LT. We identified predictors for ESBL-E infection in carriers that may help in rationalizing carbapenem prescription. Perioperative AP targeting colonizing ESBL-E may be associated with a reduced risk of post-LT ESBL-E infections.

Liver failure in pregnancy: a review of 25 cases

We retrospectively reviewed the medical records from 25 pregnant women with liver failure from May 2009 to July 2019. Data describing clinical symptoms and manifestations, routine blood analyses, coagulation, and liver and kidney function were extracted. Swansea criteria were assessed to identify variables with prognostic significance for maternal mortality. The results showed that acute fatty liver was the primary cause of liver failure and 8 (88.89%) patients died within 7 days. Swansea diagnostic criteria for assessing the severity of liver failure were consistent with Chinese guidelines and were more systematic and convenient. The incidence of postpartum haemorrhage was 76%, and the velocity of bleeding was approximately 600 mL per hour. Increased Swansea score, hepatic encephalopathy and decreased PWR were important prognostic indicators for mortality. Recovery during the 7 days postpartum period was an important determinant of maternal outcomes.Impact statementWhat is already known on this subject? Liver failure in pregnant women is a rare but potentially devastating disease with a high rate of short-term morbidity and mortality. There are limited reports about clinical predictors of maternal-foetal outcomes and the dilemmas faced in the term of delivery.What the results of this study add? The incidence of postpartum haemorrhage was 76% in pregnant women with liver failure, but the velocity of bleeding was approximately 600 mL per hour. Our study revealed the Swansea score and the ratio of hepatic encephalopathy were significantly higher and platelet-to-white blood cell ratio (PWR) was lower in women who died compared to those who survived. During treatment period, 8 (88.89%) patients died within 7 days.What the implications are of these findings for clinical practice and/or further research? Swansea score, hepatic encephalopathy and PWR were important prognostic indicators for mortality in pregnant women with liver failure. Recovery during the 7 days postpartum period was an important determinant of maternal outcomes. Our findings may prompt researchers to conduct a large multicentre study to evaluate the prognostic indicators for mortality in pregnant women with liver failure.

Beta-D-Glucan Levels With Use of an Anti-adhesion Barrier Film in Pediatric Living Donor Liver Transplantation

INTRODUCTION

Serum beta-D-glucan (BDG) levels may increase with anti-adhesion barrier film (ABF) use during pediatric living donor liver transplantation (LDLT). It may affect detection of fungal infections after LDLT. We evaluate BDG levels after pediatric LDLT.

METHODS

Pediatric patients who received an ABF during LDLT were included. Patients who may have had fungal infections prior to LDLT were excluded. One sheet of ABF was placed in the peritoneum during abdominal closure. Serum BDG levels before transplantation and on postoperative days (PODs) 1, 4, 7, 14, 21, and 28 and peritoneal fluid BDG levels on PODs 1 and 7 were measured.

RESULTS

Sixteen patients received an ABF during LDLT. Median age at transplant was 1.9 years (range, 6-11 years). Median body weight was 12.6 kg (range, 6.8-39 kg). Indications for LDLT were biliary atresia (n = 10) and other (n = 5). Prior to transplantation, the mean serum BDG level was 3.8 pg/mL. Mean Serum BDG levels were 18.1, 38.3, 5.3, 3.8, 3.3, and 3.3 pg/mL on PODs 1, 4, 7, 14, 21, and 28, respectively. Mean peritoneal fluid BDG levels were 485.9 and 240.4 pg/mL on PODs 1 and 7, respectively. No clinical fungal infections were observed.

CONCLUSIONS

BDG levels were high in serum and peritoneal fluid after pediatric LDLT. Serum BDG levels normalized after POD 7. Careful interpretation of BDG levels until POD 7 is needed when an ABF has been used.

Mucosal expression of defensin-5, soluble phospholipase A2 and lysozyme in the intestine in a rat model of acute liver failure and its relationship to intestinal bacterial translocation

INTRODUCTION

To study the expression of defensin-5 (RD-5), soluble phospholipase A2 (sPLA2) and lysozyme in the intestine in a rat model of acute liver failure and its relationship with intestinal bacterial translocation (BT).

PATIENTS AND METHODS

Sprague-Dawley (SD) rats were divided into two groups. The experimental group was divided into five subgroups according to the lapsing time after the model was established, which were designated accordingly as 8h, 16h, 24h, 48h, and 72h groups. Acute liver failure (ALF) model was induced by intraperitoneal injection of 10% d-galactosamine. The homogenates of mesenteric lymph nodes (MLNs), liver and spleen from each group were cultured in agar to determine the bacterial outgrowth. The mRNA expression of RD-5, sPLA2, lysozyme and the protein expression of sPLA2, lysozyme were determined.

RESULTS

No bacteria grew in the organ cultures from the control group while experimental groups had positive cultures. Expression of the RD-5 and sPLA2 mRNA in the experimental groups gradually increased at early time points and peaked 16h after induction of ALF, then progressively decreased. The mRNA expression of lysozyme in the experimental group peaked at 8h after ALF induction, then progressively decreased. Similar results were obtained with Western blot and immunohistochemical staining.

DISCUSSION

The immune barrier function of the ileal mucosa in the rat model of acute liver failure was compromised as demonstrated by the decreased expression of RD-5, sPLA2 and lysozyme in Paneth cells along with increased intestinal bacterial translocation.

Vaccination in adult liver transplantation candidates and recipients

In patients with chronic liver disease and liver transplant recipients, cirrhosis-associated immune dysfunction syndrome and immunosuppressant drug regimens required to prevent graft rejection lead to a high risk of severe infections, associated with acute liver decompensation, graft loss and increased mortality. In addition to maintain their global health status, vaccination represents a major preventive measure against specific infectious risks of particular concern in this population, such as invasive pneumococcal diseases, influenza or viral hepatitis A and B. However, immunization in this setting raises several issues: i) recommended vaccination schedules rely on sparse immunogenicity data without clinical efficacy and effectiveness trials designed for this specific population; ii) dynamics of immunosuppression makes timing of immunization challenging; iii) live attenuated vaccines are contraindicated after transplantation; and iv) vaccines tolerance is poorly known in cirrhotic patients. This review outlines the rational for vaccination in adult liver transplant candidates and recipients and available data regarding immunization in this specific population.

Risk stratification for early bacteremia after living donor liver transplantation: a retrospective observational cohort study

BACKGROUND

This study investigated perioperative clinical risk factors for early post-transplant bacteremia in patients undergoing living donor liver transplantation (LDLT). Additionally, postoperative outcomes were compared between patients with and without early post-transplant bacteremia.

METHODS

Clinical data of 610 adult patients who underwent elective LDLT between January 2009 and December 2018 at Seoul St. Mary's Hospital were retrospectively collected. The exclusion criteria included overt signs of infection within 1 month before surgery. A total of 596 adult patients were enrolled in this study. Based on the occurrence of a systemic bacterial infection after surgery, patients were classified into non-infected and infected groups.

RESULTS

The incidence of bacteremia at 1 month after LDLT was 9.7% (57 patients) and Enterococcus faecium (31.6%) was the most commonly cultured bacterium in the blood samples. Univariate analysis showed that preoperative psoas muscle index (PMI), model for end-stage disease score, utility of continuous renal replacement therapy (CRRT), ascites, C-reactive protein to albumin ratio, neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio, and sodium level, as well as intraoperative post-reperfusion syndrome, mean central venous pressure, requirement for packed red blood cells and fresh frozen plasma, hourly fluid infusion and urine output, and short-term postoperative early allograft dysfunction (EAD) were associated with the risk of early post-transplant bacteremia. Multivariate analysis revealed that PMI, the CRRT requirement, the NLR, and EAD were independently associated with the risk of early post-transplant bacteremia (area under the curve: 0.707; 95% confidence interval: 0.667-0.745; p < 0.001). The overall survival rate was better in the non-infected patient group. Among patients with bacteremia, anti-bacterial treatment was unable to resolve infection in 34 patients, resulting in an increased risk of patient mortality. Among the factors included in the model, EAD was significantly correlated with non-resolving infection.

CONCLUSIONS

We propose a prognostic model to identify patients at high risk for a bloodstream bacterial infection; furthermore, our findings support the notion that skeletal muscle depletion, CRRT requirement, systemic inflammatory response, and delayed liver graft function are associated with a pathogenic vulnerability in cirrhotic patients who undergo LDLT.

Novel strategies for the management of bacterial and fungal infections in patients with liver cirrhosis: focus on new antimicrobials

Introduction: Liver cirrhosis is a frequent condition caused by different etiologies. Bacterial and fungal infections are common complications, representing an independent prognostic stage in patients with cirrhosis, dramatically worsening their clinical outcomes.Areas covered: The present review article addresses manifold points and to this purpose an inductive literature search of MEDLINE database through PubMed was performed. First, it provides an overview on the mechanisms underlying immune disfunctions in patients with cirrhosis, who are prone to develop infections being at higher risk than the general population. Second, commonest types of bacterial and fungal infections in patients with advanced liver disease are described, focusing on their deleterious impact as decompensating events. Third, the rise of multidrug-resistant (MDR) bacteria and fungi as causative agents of infection in cirrhotic subjects is illustrated. Eventually, the most promising novel therapeutic options against MDR pathogens and fungi are reviewed.Expert opinion: The management of bacterial and fungal infections in patients with cirrhosis is difficult, due to the frequent co-existence of renal impairment, low platelet count and other conditions that limit the antimicrobial choice. New antibacterial and antifungal compounds may overcome this issue by providing a better tolerability profile, along with equal or superior efficacy compared with older drugs.

Prevalence, Risk Factors And Treatment Of The Most Common Gram-Negative Bacterial Infections In Liver Transplant Recipients: A Review

Advances in surgical techniques and immunosuppressive agents have made solid organ transplant (Tx) an important strategy for treatment of end-stage organ failures. However, the incidence of infections following Tx due to Gram-negative pathogens is on the rise. These infections are associated with increased mortality and morbidity in patients following transplantation, including liver Tx. Thus, managing infections in liver Tx recipients is a big challenge, requiring prompt medical attention. Considering the important effect of Gram-negative bacterial infections on the outcomes of liver Tx recipients, the most prevalent Gram-negative pathogens including Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Escherichia coli will be discussed in this review.

Management of Antimicrobial Agents in Abdominal Organ Transplant Patients in Intensive Care Unit

PURPOSE OF REVIEW

Early diagnosis of infections and immediate initiation of appropriate antimicrobials are crucial in the management of patients before and after organ transplantation. We reviewed the most recent literature and guidelines in this field and organized the current recommendations for healthcare professionals caring for critically ill organ transplant recipients.

RECENT FINDINGS

The incidence of multidrug-resistant organisms is increasing. Multidrug-resistant Gram-negative bacteria comprise about 14% of organisms. Vancomycin-resistant enterococci bloodstream infections are also on the rise, as 20.5% of nosocomial enterococci are now vancomycin-resistant, changing empiric antibiotic selection. Fluconazole-resistant Candida species comprise up to 46% of cases of candidemia in hospitalized patients. Consequently, new guidelines recommend primary use of echinocandins in patients with candidemia who have moderate-to-severe disease. Finally, the incidence of emergence of ganciclovir-resistant cytomegalovirus infection in patients is 5-12%, requiring early recognition and change to alternative regimens in the case of poor response to therapy.

SUMMARY

Bloodstream infections are a major cause of mortality and morbidity in solid organ transplantation. Mortality as high as 24% and 50% have been reported with sepsis and septic shock respectively. As such, bloodstream infections should be diagnosed rapidly and intravenous antibiotics should be started immediately. Appropriate resuscitation should be initiated and the number and/or dose of immunosuppressive drugs should be reduced. Proper source control must also be achieved with radiologic drainage or surgical intervention as appropriate. Initial antibiotic treatment of these patients should cover both Gram-positive organisms, especially in the presence of intravascular catheters, and Gram-negative bacteria. Echinocandins like caspofungin should also be considered especially in critically ill patients, particularly if a patient has been on total parenteral nutrition or broad-spectrum antibiotics.

Predictive utility of the C-reactive protein to albumin ratio in early allograft dysfunction in living donor liver transplantation: A retrospective observational cohort study

BACKGROUND

This study was performed to determine the association between the ratio of C-reactive protein to albumin (CRP/ALB) and the risk of early allograft dysfunction (EAD) in patients undergoing living donor liver transplantation (LDLT).

PATIENTS AND METHODS

A total of 588 adult patients undergoing LDLT were retrospectively investigated, after 22 were excluded because of signs of overt infection or history of ALB infusion. The study population was classified into high and low CRP/ALB ratio groups according to EAD. All laboratory variables, including CRP and ALB, had been collected on the day before surgery. A percentage value for the CRP/ALB ratio (%) was calculated as CRP/ALB × 100.

RESULTS

After LDLT, 83 patients (14.1%) suffered EAD occurrence. A higher CRP/ALB ratio was independently associated with risk of EAD, Model for End-stage Liver Disease score, fresh frozen plasma transfusion, and donor age. Based on a cutoff CRP/ALB ratio (i.e., > 20%), the probability of EAD was significantly (2-fold) higher in the high versus low CRP/ALB group. The predictive utility of CRP/ALB ratio for EAD was greater than those of other inflammatory markers. In addition, patients with a high CRP/ALB ratio had poorer survival than those with a low CRP/ALB ratio during the follow-up period.

CONCLUSIONS

The easily calculated CRP/ALB ratio may allow estimation of the risk of EAD after LDLT and can provide additional information that may facilitate the estimation of a patient's overall condition.

Post-transplant infection improves outcome of hepatocellular carcinoma patients after orthotopic liver transplantation

BACKGROUND

Tumor recurrence after orthotopic liver transplantation (OLT) remains a serious threat for long-term survival of the recipients with hepatocellular carcinoma (HCC), since very few factors or measures have shown impact on overcoming HCC recurrence after OLT. Postoperative infection suppresses tumor recurrence and improves patient survival in lung cancer and malignant glioma probably via stimulating the immune system. Post-transplant infection (PTI), a common complication, is deemed to be harmful for the liver transplant recipients from a short-term perspective. Nevertheless, whether PTI inhibits HCC recurrence after OLT and prolongs the long-term survival of HCC patients needs to be clarified.

AIM

To investigate the potential influence of PTI on the survival and tumor recurrence of patients with HCC after OLT.

METHODS

A total of 238 patients with HCC who underwent OLT between August 2002 and July 2016 at our center were retrospectively included and accordingly subdivided into a PTI group (53 patients) and a non-PTI group (185 patients). Univariate analyses, including the differences of overall survival (OS), recurrence-free survival (RFS), and post-recurrence survival (PRS), between the PTI and non-PTI subgroups as well as survival curve analysis were performed by the Kaplan-Meier method, and the differences were compared using the log rank test. The variables with a P-value < 0.1 in univariate analyses were included in the multivariate survival analysis by using a Cox proportional-hazards model.

RESULTS

The 1-, 3-, and 5-year OS and RFS rates of the whole cohort were 86.6%, 69.0%, and 63.6%, and 75.7%, 60.0%, and 57.3%, respectively. The 1-, 3-, and 5-year OS rates for the PTI patient group (96.0%, 89.3%, and 74.0%) were significantly higher than those for the non-PTI group (84.0%, 63.4%, and 60.2%) (P = 0.033). The absence of PTI was an independent risk factor for dismal OS (relative risk [RR] = 2.584, 95%CI: 1.226-5.449) and unfavorable RFS (RR = 2.683, 95%CI: 1.335-5.390). Subgroup analyses revealed that PTI remarkably improved OS (P = 0.003) and RFS (P = 0.003) rates of HCC patients with vascular invasion (IV), but did not impact on OS (P = 0.404) and RFS (P = 0.304) of patients without VI. Among the patients who suffered post-transplant tumor recurrence, patients with PTI showed significantly better OS (P = 0.026) and PRS (P = 0.042) rates than those without PTI.

CONCLUSION

PTI improves OS and RFS of the transplant HCC patients at a high risk for post-transplant death and tumor recurrence, which is attributed to suppressive effect of PTI on HCC recurrence.

Spontaneous fungal peritonitis: Micro-organisms, management and mortality in liver cirrhosis-A systematic review

BACKGROUND

Spontaneous peritonitis is an infection of ascitic fluid without a known intra-abdominal source of infection. spontaneous fungal peritonitis (SFP) is a potentially fatal complication of decompensated cirrhosis, defined as fungal infection of ascitic fluid in the presence of ascitic neutrophil count of greater than 250 cells/mL.

AIM

To determine the prevalence of fungal pathogens, management and outcomes (mortality) of SFP in critically ill cirrhotic patients.

METHODS

Studies were identified using PubMed, EMBASE, Cochrane Central Register of Controlled Trials and Scopus databases until February 2019. Inclusion criteria included intervention trials and observation studies describing the association between SFP and cirrhosis. The primary outcome was in-hospital, 1-mo, and 6-mo mortality rates of SFP in cirrhotic patients. Secondary outcomes were fungal microorganisms identified and in hospital management by anti-fungal medications. The National Heart, Lung and Blood Institute quality assessment tools were used to assess internal validity and risk of bias for each included study.

RESULTS

Six observational studies were included in this systematic review. The overall quality of included studies was good. A meta-analysis of results could not be performed because of differences in reporting of outcomes and heterogeneity of the included studies. There were 82 patients with SFP described across all the included studies. Candida species, predominantly Candida albicans was the fungal pathogen in majority of the cases (48%-81.8%) followed by Candida krusei (15%-25%) and Candida glabrata (6.66%-20%). Cryptococcus neoformans (53.3%) was the other major fungal pathogen. Antifungal therapy in SFP patients was utilized in 33.3% to 81.8% cases. The prevalence of in hospital mortality ranged from 33.3% to 100%, whereas 1-mo mortality ranged between 50% to 73.3%.

CONCLUSION

This systematic review suggests that SFP in end stage liver disease patient is associated with high mortality both in the hospital and at 1-mo, and that antifungal therapy is currently underutilized.