Bacterial, mycobacterial, and protozoal infections after liver transplantation--part I

Perioperative Use of IgM-Enriched Immunoglobulins in Liver Transplantation Recipients at High Risk for Infections: A Preliminary Study

Background: Infections frequently occur after orthotopic liver transplantation (OLT) and are associated with increased mortality. In 2018, we introduced perioperative administration of intravenous immunoglobulin enriched in IgM as an optional therapy in recipients at a high risk of infection. This preliminary study evaluated whether this preparation reduced infections in the early post-transplantation period. Methods: Adult patients with a high risk of postoperative infections who underwent OLT between January 2014 and December 2021 in our center were included in the study. The primary outcome was the occurrence of new postoperative bacterial and fungal infections within the first 30 days after OLT. Results: Ninety recipients at a high risk of postoperative infections who underwent OLT were included, of whom 51 (57%) received IgM preparation. Patients treated and not treated with IgM were similar in terms of demographics, model of end-stage liver disease score, and risk factors for postoperative infections. The occurrence of new infections was lower (absolute risk reduction (ARR) 21.2%; p = 0.038) in patients who received IgM than in those who did not. Multivariate analysis adjusted for confounders (OR 0.348; p = 0.033) and propensity score-based matching analysis (ARR 21.2%, p = 0.067) confirmed an association between IgM preparation and lower occurrence of postoperative infections. The 90-day mortality rate was lower (ARR 13.4%, p = 0.018) in patients who received IgM preparation. Conclusions: In OLT recipients at high risk for infections, perioperative administration of an IgM-enriched preparation seems to reduce the development of new infections within the first 30 days after OLT.

Epidemiology and Management of Infections in Liver Transplant Recipients

Background: Improvements in liver transplant (LT) outcomes are attributed to advances in surgical techniques, use of potent immunosuppressants, and rigorous pre-LT testing. Despite these improvements, post-LT infections remain the most common complication in this population. Bacteria constitute the most common infectious agents, while fungal and viral infections are also frequently encountered. Multi-drug-resistant bacterial infections develop because of polymicrobial overuse and prolonged hospital stays. Immediate post-LT infections are commonly caused by viruses. Conclusions: Appropriate vaccination, screening of both donor and recipients before LT and antiviral prophylaxis in high-risk individuals are recommended. Antimicrobial drug resistance is common in high-risk LT and associated with poor outcomes; epidemiology and management of these cases is discussed. Additionally, we also discuss the effect of coronavirus disease 2019 (COVID-19) infection and monkeypox in the LT population.

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.

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.

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.

The Role of Microbiota in Liver Transplantation and Liver Transplantation-Related Biliary Complications

Liver transplantation as a treatment option for end-stage liver diseases is associated with a relevant risk for complications. On the one hand, immunological factors and associated chronic graft rejection are major causes of morbidity and carry an increased risk of mortality due to liver graft failure. On the other hand, infectious complications have a major impact on patient outcomes. In addition, abdominal or pulmonary infections, and biliary complications, including cholangitis, are common complications in patients after liver transplantation and can also be associated with a risk for mortality. Thereby, these patients already suffer from gut dysbiosis at the time of liver transplantation due to their severe underlying disease, causing end-stage liver failure. Despite an impaired gut-liver axis, repeated antibiotic therapies can cause major changes in the gut microbiome. Due to repeated biliary interventions, the biliary tract is often colonized by several bacteria with a high risk for multi-drug resistant germs causing local and systemic infections before and after liver transplantation. Growing evidence about the role of gut microbiota in the perioperative course and their impact on patient outcomes in liver transplantation is available. However, data about biliary microbiota and their impact on infectious and biliary complications are still sparse. In this comprehensive review, we compile the current evidence for the role of microbiome research in liver transplantation with a focus on biliary complications and infections due to multi-drug resistant germs.

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.

Analysis of Risk Factors for Carbapenem-Resistant Klebsiella pneumoniae Infection and Its Effect on the Outcome of Early Infection After Kidney Transplantation

Background

Infections remain a major cause of morbidity and mortality in kidney transplant (KT) recipients. This study was performed to identify the overall prevalence of early infections, prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) infection after KT, one-year postoperative mortality in patients with early infections and risk factors for CRKP infections.

Methods

We conducted a retrospective study of all patients who received KT in our hospital between January 2017 and December 2019. We evaluated the demographic, clinical, infection characteristics and the one-year postoperative outcomes.

Results

Among the 419 patients who received KT between January 2017 and December 2019, 150 patients had at least one infection within 90 days after KT. The total prevalence of early infections was 36.1% (150/415), the prevalence of early CRKP infections was 10.4% (43/415), and the one-year postoperative mortality was 15.3% (23/150) in patients with early infections. The risk factors independently related to one-year postoperative mortality were mechanical ventilation (MV) > 48 h (Odds ratio (OR)= 13.879, 95%Confidence interval (CI): 2.265~85.035; P=0.004) and CRKP infection (OR=6.751, 95% CI: 1.051~43.369; P =0.044). MV> 48 h was independently related to CRKP infection (OR=3.719, 95% CI: 1.024~13.504; P=0.046). Kaplan-Meier survival curves showed that the one-year survival rate of patients infected with CRKP in the early postoperative stage was significantly lower than that of uninfected patients.

Conclusions

In general, the prevalence of early infections after KT is high, and CRKP infection is closely correlated with poor prognosis. The effective prevention and treatment of CRKP infection is an important way to improve the one-year survival rate after KT.

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.

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.

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.

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.

Extracorporeal membrane oxygenation support for refractory septic shock in liver transplantation recipients

Purpose

This study was designed to assess the outcome of the extracorporeal membrane oxygenation (ECMO) in liver transplantation (LT) recipients with refractory septic shock and predict the prognosis of those cases.

Methods

From February 2005 to October 2012, ECMO was used in 8 cases of refractory septic shock. Laboratory values including lactate and total bilirubin level just before starting ECMO were obtained and sepsis-related organ failure assessment (SOFA) score, acute physiology and chronic health evaluation (APACH) II score and simplified acute physiology score (SAPS) 3 were calculated. Subsequent peak serum lactate and total bilirubin level, and SOFA score after 24 hours of starting ECMO were measured.

Results

Comparisons were made between survivors and nonsurvivors. ECMO was weaned off successfully in 3 patients (37.5%) and 2 patients (25%) survived to hospital discharge. Clinical scores including SOFA, APACH II, and SAPS3 and laboratory results including lactate, total bilirubin and CRP were not significantly different between survivor and nonsurvivor groups. Lactate level and SOFA score tended to decrease after ECMO support in survivor group and total bilirubin and CRP level tended to increase in nonsurvivor group.

Conclusion

Our findings suggest that the implantation of ECMO might be considered in highly selected LT recipients with refractory septic shock.

Liver allograft biopsies with histological cholestasis: a clinicopathological study of 254 cases from a single centre

AIMS

Liver allograft biopsy is important in the management of liver transplant (LT) recipients. Cholestasis is an indicator of liver dysfunction, and histological evidence of cholestasis can be observed in a wide range of pathological entities in the post-LT setting. In this study, we describe the clinicopathological features and significance of liver allograft biopsies with histological cholestasis over 11 years in our centre.

METHODS

Liver allograft biopsies performed in Queen Mary Hospital, Hong Kong from 2004 to 2014 showing histological cholestasis were retrieved from the pathology archive. Clinical and pathological data were retrospectively reviewed and analyzed.

RESULTS

Among the 254 biopsies from 167 patients, large duct obstruction (LDO) and acute cellular rejection (ACR) were the two main aetiologies associated with cholestasis. There was a decrease in sepsis as a cause over the study duration. In cases showing cholestasis at 6 months or more after LT, LDO was more common than ACR. Over half (61%) of the 254 biopsies showed mild cholestasis. Severe panacinar cholestasis was more often observed in LDO. Mild cholestasis was most commonly observed regardless of the severity of ACR. Severe cholestasis was associated with poorer 1-year and 3-year graft survival and patient survival, as well as higher 3-month and 6-month post-biopsy mortality.

CONCLUSION

Histological cholestasis and its severity in liver allograft biopsies has clinical and prognostic significance. Our study summarizes our previous experience and provides further insights into the management of post-LT patients.

Epidemiology and risk factors for infection after living donor liver transplantation

The epidemiology of infections after living donor liver transplantation (LDLT) is limited. We aimed to study the epidemiology and risk factors of infections after LDLT. The medical records of 223 adult patients who underwent LDLT from January 1, 2000 to August 31, 2015 were reviewed for all infections occurring up to 1 year. We estimated the cumulative incidence of infection using the Kaplan-Meier product limit method. Risk factors were analyzed with time-dependent Cox regression modeling. The majority of patients were Caucasian (94.6%) and male (64.6%), and the median age at transplantation was 55 years. The most common indication for transplantation was primary sclerosing cholangitis (37.7%). A total of 122 patients developed an infection during the follow-up period (1-year cumulative event rate of 56%), with the majority (66%) of these occurring within 30 days after transplantation. Enterococcus sp. was the most frequent pathogen identified. Multivariate analysis showed that increased Model for End-Stage Liver Disease (MELD) score (per 10-point change: hazard ratio [HR], 1.59), history of recurrent infections prior to transplant (HR, 2.01), Roux-en-Y anastomosis (HR, 2.37), increased log-number of packed red blood cell transfusions (HR, 1.39), and biliary complications (HR, 4.26) were independently associated with a higher risk of infection. Infections occur commonly after LDLT, with most infections occurring early and being related to the hepatobiliary system. Higher MELD scores, the type of biliary anastomosis, presence of biliary complications, and prior pretransplant infections are independently associated with a higher risk for infections. Liver Transplantation 23 465-477 2017 AASLD.

Small-for-Size Syndrome: Bridging the Gap Between Liver Transplantation and Graft Recovery

In living donor liver transplantation, optimal graft size is estimated from values like graft volume/standard liver volume and graft/recipient body weight ratio but the final functional hepatic mass is influenced by other donor and recipient factors. Grafts with insufficient functional hepatic mass can produce a life-threatening condition with rapidly progressive liver failure called small-for-size syndrome (SFSS). Diagnosis of SFSS requires careful surveillance for signs of inadequate hepatocellular function, residual portal hypertension, and systemic inflammation that suggest rapidly progressive liver failure. Early diagnosis, symptom control, and addressing the cause of SFSS may prevent the need for retransplantation. With increased attention to avoiding donor risk, intensivists will be confronted with more SFSS recipients. In this review, we aim to outline a systematic approach to the medical management of patients with SFSS by providing a concise synopsis of general supportive care—neurological, cardiovascular, and renal support, mechanical ventilation, nutritional support, infection control, and tailored immunosuppression—with an aim to avoid end-organ damage or death and a review of current interventions including liver support devices, portal flow modulating drugs, and other experimental interventions that aim to preserve existing hepatic mass and improve conditions for hepatic regeneration. We examine evidence for SFSS interventions to provide the reader with information that may assist in clinical decision making. Points of controversy in care are purposefully highlighted to identify areas where additional experimental work is still needed. A full understanding of the pathophysiology of SFSS and measures to support liver regeneration will guide effective management.

Carbapenem-Resistant Klebsiella pneumoniae influences the outcome of early infections in liver transplant recipients

Background

Infections remain a leading cause of morbidity and mortality among liver transplant (LT) recipients. The aim of our study was to define the factors associated with outcome of early bacterial and fungal infections in a cohort of patients who underwent LT at the University Hospital of Ancona over a nine year period.

Methods

All consecutive patients who underwent LT in our center were considered. An early infection was defined as occurring in the first month post-transplantation.

Results

Among 330 patients who underwent LT from August 2005 to October 2014, 88 (27 %) had at least one infection documented within 30 days after transplantation. In 54 cases only one site was involved, in 34 cases ≥2 sites. There were 43 (30 %) pneumonia, 40 (27 %) surgical site infections, 31 (22 %) blood stream infections, and 30 (21 %) urinary tract infections. Gram-negative bacteria accounted for 64 % of the culture-positive cases, followed by Gram-positive bacteria (30 %) and fungi (6 %). A high proportion of drug-resistant strains was found within either Gram-negative (79 %) or Gram-positive (81 %) bacteria. There were 27 out 88 patients (31 %) who died within 180 days from the transplant. Factors independently associated with a higher risk of mortality were: renal replacement therapy (HR 11.797 [CI95 % 3.082–45.152], p < 0.0001), multisite infections (HR 4.865 [CI95 % 1.417–16.700], p = 0.012) and being infected with carbapenem-resistant Klebsiella pneumoniae (CRKP; HR 5.562 [CI95 % 1.186–26.088], p = 0.030).

Conclusions

Overall, these data indicate that early infections in LT patients are characterized by significant mortality. In particular, an early infection caused by CRKP has an adverse impact on survival in these patients suggesting an urgent need for adopting preventive measures to avoiding this complication.

Multidrug-resistant Combined Infections in a Liver Transplanted Patient: Case Report

We report a case of successfully treated multiple liver abscesses in a liver-transplanted patient, sustained by combined multidrug-resistant infections. Two months after a liver transplant, a computed tomography scan revealed the presence of multiple abscesses in the liver graft. Blood cultures and abscessual liver fluid were both positive for acquired colistin- and carbapenem- resistant Klebsiella pneumoniae and an extended-spectrum of beta-lactamases-producing Enterobacter aerogenes. The treatment strategy consisted of different prolonged antimicrobial combinations and draining of the abscesses with complete recovery of the liver lesions.

Postoperative effects of intraoperative hyperglycemia in liver transplant patients

OBJECTIVES

The aim of this study was to determine the effects of intraoperative hyperglycemia on postoperative outcomes in orthotopic liver transplant recipients.

MATERIALS AND METHODS

After ethics committee approval was obtained, we retrospectively analyzed the records of patients who underwent orthotopic liver transplant from January 2000 to December 2013. A total 389 orthotopic liver transplants were performed in our center, but patients aged < 15 years (179 patients) were not included in the analyses. Patients were divided into 2 groups based on their maximum intraoperative blood glucose level: group 1 (patients with intraoperative blood glucose level < 200 mg/dL) and group 2 (patients with intraoperative blood glucose level > 200 mg/dL). Postoperative complications between the 2 groups were compared.

RESULTS

There were 58 patients (37.6%; group 1, blood glucose < 200 mg/dL) who had controlled blood glucose and 96 patients (62.3%; group 2, blood glucose > 200 mg/dL) who had uncontrolled blood glucose. The mean age and weight for groups 1 and 2 were similar. There were no differences between the 2 groups regarding the duration of anhepatic phase (P = .20), operation time (P = .41), frequency of immediate intraoperative extubation (P = .14), and postoperative duration of mechanical ventilation (P = .06). There were no significant differences in frequency of patients who had postoperative infectious complications, acute kidney injury, or need for hemodialysis. Mortality rates after liver transplant were similar between the 2 groups (P = .81).

CONCLUSIONS

Intraoperative hyperglycemia during orthotopic liver transplant was not associated with an increased risk of postoperative infection, acute renal failure, or mortality.

Risk factors and outcomes of carbapenem-resistant Klebsiella pneumoniae infections in liver transplant recipients

Carbapenem-resistant Klebsiella pneumoniae (CRKP) infection is increasing in incidence and is associated with increased mortality in liver transplantation (LT) recipients. We performed a retrospective cohort study of all patients transplanted between January 2010 and January 2013 to identify the incidence and risk factors for post-LT CRKP infection and evaluate the impact of this infection on outcomes in a CRKP-endemic area. We studied 304 recipients, of whom 20 (6.6%) developed CRKP and 36 (11.8%) carbapenem-susceptible Klebsiella pneumoniae (CSKP) infections in the year following LT. Among the 20 recipients with post-LT CRKP infection, 8 (40%) were infected in ≥ 2 sites; 13 (65%) had surgical site-intra-abdominal infections; 12 (60%) had pneumonia; and 3 (15%) had a urinary tract infection. There were 6 patients with a CRKP infection before LT, 5 of whom developed a CRKP infection after LT. Significant risk factors for post-LT CRKP infection in multivariate analysis included laboratory Model for End-Stage Liver Disease at LT (odds ratio [OR], 1.07; P = 0.001), hepatocellular carcinoma (OR, 3.19; P = 0.02), Roux-en-Y biliary choledochojejunostomy (OR, 3.15; P = 0.04), and bile leak (OR, 5.89; P = 0.001). One-year estimated patient survival was 55% (95% confidence interval, 31%-73%), 72% (55%-84%), and 93% (89%-96%), for patients with CRKP, CSKP, and no Klebsiella pneumoniae infection, respectively. In multivariate analysis, CRKP (hazard ratio [HR], 6.92; P < 0.001) and CSKP infections (CSKP, HR, 3.84; P < 0.001), as well as bile leak (HR, 2.10; P = 0.03) were the strongest predictors of post-LT mortality. In an endemic area, post-LT CRKP infection is common, occurring in 6.6% of recipients, and is strongly associated with post-LT mortality. Improved strategies for screening and prevention of CRKP infection are urgently needed.

Bacterial and fungal infections in the early post-transplantation period after liver transplantation: etiologic agents and their susceptibility

OBJECTIVE

It has been reported in many studies that one of the main factors influencing morbidity and mortality in patients receiving transplants is infection after transplantation.

PATIENTS AND METHODS

The study included 190 adult patients undergoing orthotopic liver transplantation (OLT) between September 2001 and December 2007. All the patients were followed prospectively for infections from the OLT date and during the first 4 weeks after surgery. Immunosuppression consisted of steroids and tacrolimus. Antimicrobial prophylaxis included piperacillin/tazobactam, fluconazole, and selective bowel decontamination (SBD) was performed. Samples of clinical materials were investigated for microbiological cultures. The micro-organisms were cultured and identified in accordance with standard bacteriological procedures. Susceptibility testing was performed using Clinical and Laboratory Standards Institute procedures.

RESULTS

From 190 OLT recipients, 2213 clinical samples were obtained for microbiological examination. Positive cultures were found in 27.2% (n = 603) of all samples tested; 1252 strains were collected. Gram-positive bacteria were found in 64.1% (n = 802), Gram-negative bacteria were found in 31.6% (n = 396), and fungal strains were isolated in 4.3% (n = 54). Surgical site specimens (n = 1031) were obtained from 190 recipients during the first month after transplantation. Positive cultures accounted for 29.2% (n = 301) of all samples tested. Among the isolated microbial strains (n = 677), most common were Gram-positive bacteria (73.7%; n = 499). Gram-negative bacteria comprised 25.1% (n = 170). There were fungal strains in 1.2% (n = 8). There were 539 urine specimens. Positive cultures accounted for 16.7% (n = 90) of those. Among the isolated microbial strains (n = 210), most common were Gram-negative bacteria (62.4%; n = 131). Gram-positive bacteria comprised 28.6% (n = 60) and fungi 9% (n = 19). There were 549 blood specimens. Positive cultures were found in 30.6% (n = 168) of all samples tested. Among the isolated microbial strains (n = 263), most common were Gram-positive bacteria in 72.3% (n = 190); Gram-negative bacteria were found in 26.2% (n = 69), and fungal strains were isolated in 1.5% (n = 4). There were 69 respiratory tract specimens. Positive cultures were found in 46.4% (n = 32) of all samples tested. Among the isolated microbial strains (n = 84), most common were Gram-positive bacteria (51.2%; n = 43); Gram-negative bacteria comprised 27.4% (n = 23) and fungi 21.4% (n = 18).

CONCLUSIONS

(1) Surgical site samples were predominated samples after LTx. (2) Our study showed Gram-positive bacteria were 64.1% (n = 802), Gram-negative bacteria, 31.6% (n = 396) and fungal strains isolated in 4.3% (n = 54). (3) The increased proportion of isolates of multi-drug-resistant bacterial strains (methicillin resistant coagulase negative Staphylococcus, vancomycin-resistant Enterococcus, high-level aminoglycoside resistance, and extended- spectrum β-lactamase). (4) These data indicate strict cooperation infection control procedures in these patients.

Bacterial and fungal infections in the early post-transplant period after kidney transplantation: etiological agents and their susceptibility

BACKGROUND

Infections remain serious complications in solid-organ transplant recipients, despite professional medical care, the introduction of new immunosuppressive drugs, and treatment that decreases the risk of infections.

METHODS

The study covered 295 adult patients undergoing kidney transplantation (KTx) between September 2001 and December 2007. All the patients were followed prospectively for infections from the KTx date and during the first 4 weeks after surgery. Samples of clinical materials were investigated for microbiological cultures. The microorganisms were cultured and identified in accordance with standard bacteriological procedures. Susceptibility testing was carried out through the use of Clinical and Laboratory Standards Institute procedures.

RESULTS

From 295 KTx recipients, 1073 clinical samples were taken for microbiological examination. Positive cultures were 26.9% (n = 289) of all samples tested; 525 strains were collected. Gram-positive bacteria were isolated in 52.2% (n = 274), Gram-negative bacteria were isolated in 40.8% (n = 214), and fungal strains were isolated in 7% (n = 37). Urine specimens (n = 582) were obtained from 84.5% of 245 recipients during the first month after transplantation. Among the isolated bacterial strains (n = 291), the most common were Gram-negative bacteria (56.4%). Gram-positive bacteria comprised 35.7%; fungal strains were found in 23 cases (7.9%). In surgical site specimens (n = 309), Gram-positive bacteria (72.1%) were the most common. Gram-negative bacteria comprised 24.4%. In blood specimens (n = 138), Gram-positive bacteria (81.6%) were the most common. Gram-negative bacteria comprised 15.8%; fungi were isolated in 2.6%. In respiratory tract specimens (n = 13), among the isolated bacterial strains (n = 8), the most common were Gram-positive bacteria (57.1%). Gram-negative bacteria comprised 14.3%; fungi were isolated in 28.6%.

CONCLUSIONS

Urine samples were predominantly positive after KTx. Our study showed Gram-positive bacteria in 52.2% after kidney transplantation. The proportion of isolates of multi-drug-resistant bacterial strains (MRCNS, vancomycin-resistant strains, high-level aminoglycoside-resistant strains, extended-spectrum beta-lactamase producers, and high-level aminoglycoside-resistant strains) was increased. These data indicate the need for strict adherence to infection control procedures in these patients.

Infections after orthotopic liver transplantation

Opportunistic infections are a leading cause of morbidity and mortality after orthotopic liver transplantation. Systemic immunosuppression renders the liver recipient susceptible to de novo infection with bacteria, viruses and fungi post-transplantation as well to reactivation of pre-existing, latent disease. Pathogens are also transmissible via the donor organ. The time from transplantation and degree of immunosuppression may guide the differential diagnosis of potential infectious agents. However, typical systemic signs and symptoms of infection are often absent or blunted after transplant and a high index of suspicion is needed. Invasive procedures are often required to procure tissue for culture and guide antimicrobial therapy. Antimicrobial prophylaxis reduces the incidence of opportunistic infections and is routinely employed in the care of patients after liver transplant. In this review, we survey common bacterial, fungal, and viral infections after orthotopic liver transplantation and highlight recent developments in their diagnosis and management.

[Intensive care treatment before and after liver transplantation]

BACKGROUND

Liver transplantation (LT) has become an established therapeutic option for patients with acute and chronic liver failure. Overall survival has dramatically increased over the last decades, mainly due to improved surgical techniques, the introduction of new immunosuppressive and anti-infective drugs but also due to continuous progress in the pre- and post-operative intensive care management of these patients.

AIM

This article aims to give a short overview of the main aspects regarding pre- and post-LT critical care issues.

RESULTS

Intensive care treatment plays a major role in the management of patients with acute and acute-on-chronic liver failure in order to enable a life-saving LT for these patients. Severe infections/sepsis mostly accompanied by multi-organ failure represent the major challenges for intensive care specialists. The immediate postoperative care takes place in the intensive care unit (ICU) in almost all patients. The expected ICU stay has been significantly shortened over the years to an average of about 1-2 days. Infections as well as acute kidney injury are the main complications in the first post-operative weeks being responsible for prolonged ICU stays. Immunologic and surgical complications are additional important issues in the post-LT intensive care setting.

CONCLUSION

The intensive care management pre and post LT is an important, multidisciplinary challenge in the successful treatment of patients with acute and chronic liver failure.

Management of infections pre- and post-liver transplantation: report of an AISF consensus conference

The burden of infectious diseases both before and after liver transplantation is clearly attributable to the dysfunction of defensive mechanisms of the host, both as a result of cirrhosis, as well as the use of immunosuppressive agents. The present document represents the recommendations of an expert panel commended by the Italian Association for the Study of the Liver (AISF), on the prevention and management of infectious complications excluding hepatitis B, D, C, and HIV in the setting of liver transplantation. Due to a decreased response to vaccinations in cirrhosis as well as within the first six months after transplantation, the best timing for immunization is likely before transplant and early in the course of disease. Before transplantation, a vaccination panel including inactivated as well as live attenuated vaccines is recommended, while oral polio vaccine, Calmette-Guerin's bacillus, and Smallpox are contraindicated, whereas after transplantation, live attenuated vaccines are contraindicated. Before transplant, screening protocols should be divided into different levels according to the likelihood of infection, in order to reduce costs for the National Health Service. Recommended preoperative and postoperative prophylaxis varies according to the pathologic agent to which it is directed (bacterial vs. viral vs. fungal). Timing after transplantation greatly determines the most likely agent involved in post-transplant infections, and specific high-risk categories of patients have been identified that warrant closer surveillance. Clearly, specifically targeted treatment protocols are needed upon diagnosis of infections in both the pre- as well as the post-transplant scenarios, not without considering local microbiology and resistance patterns.

Methods of preventing bacterial sepsis and wound complications after liver transplantation

BACKGROUND

Bacterial sepsis and wound complications after liver transplantation increase mortality, morbidity, or hospital stay and are likely to increase overall transplant costs. All liver transplantation patients receive antibiotic prophylaxis. This is an update of our 2008 Cochrane systematic review on the same topic in which we identified seven randomised clinical trials.

OBJECTIVES

To assess the benefits and harms of different methods aimed at preventing bacterial sepsis and wound complications in people undergoing liver transplantation.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and Science Citation Index Expanded to February 2013.

SELECTION CRITERIA

We included only randomised clinical trials irrespective of language or publication status. We excluded quasi-randomised and other observational studies for assessment of benefits, but not for harms.

DATA COLLECTION AND ANALYSIS

Two review authors collected the data independently. We calculated the risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI) using fixed-effect and the random-effects models based on available-case analysis.

MAIN RESULTS

We identified only seven trials for inclusion, including 614 participants. Only one trial was of low risk of bias risk. Overall, the quality of evidence was very low. There were five comparisons in the seven trials: selective bowel decontamination versus inactive control; selective bowel decontamination versus prebiotics with probiotics; selective bowel decontamination versus prebiotics; prebiotics with probiotics versus prebiotics; and granulocyte-colony stimulating factor (G-CSF) versus control. Four trials compared selective bowel decontamination versus placebo or no treatment. In one trial, participants were randomised to selective bowel decontamination, active lactobacillus with fibres (probiotic with prebiotic), or to inactivated lactobacillus with fibres (prebiotic). In one trial, active lactobacillus with fibres (probiotic with prebiotic) was compared with inactive lactobacillus with fibres (prebiotic). In the remaining trial, different doses of G-CSF and placebo were compared. There was no trial comparing different antibiotic prophylactic regimens in people undergoing liver transplantation. Most trials included adults undergoing elective liver transplantation. There was no significant difference in proportion of people who died or required retransplantation between the intervention and control groups in any of the five comparison groups. MORTALITY There were no differences between 190 participants (three trials); 5/87 (adjusted proportion: 6.2%) in selective bowel decontamination group versus 7/103 (6.8%) in inactive control group; RR 0.91 (95% CI 0.31 to 2.72); 63 participants (one trial); 0/32 (0%) in selective bowel decontamination group versus 0/31 (0%) in prebiotics with probiotics group; RR - not estimable; 64 participants (one trial); 0/32 (0%) in selective bowel decontamination group versus 0/32 (0%) in prebiotics group; RR - not estimable; 129 participants (two trials); 0/64 (0%) in prebiotics with probiotics group versus 0/65 (0%) in prebiotics group; RR - not estimable; and 194 participants (one trial); 22/124 (17.7%) in G-CSF group versus 10/70 (14.3%) in placebo group; RR 1.24 (95% 0.62 to 2.47). RETRANSPLANTATION There were no differences between 132 participants (two trials); 4/58 (adjusted proportion: 6.9%) in selective bowel decontamination group versus 6/74 (8.1%) in inactive control group; RR 0.85 (95% CI 0.26 to 2.85); 63 participants (one trial); 1/32 (3.1%) in selective bowel decontamination group versus 0/31 (0%) in prebiotics with probiotics group; RR 2.91 (0.12 to 68.81); 64 participants (one trial); 1/32 (3.1%) in selective bowel decontamination group versus 0/32 (0%) in prebiotics group; RR 3.00 (95% CI 0.13 to 71.00); 129 participants (two trials); 0/64 (0%) in prebiotics with probiotics group versus 1/65 (1.5%) in prebiotics group; RR 0.33 (95% CI 0.01 to 7.9); and 194 participants (one trial); 10/124 (7.1%) in G-CSF group versus 5/70 (7.1%) in placebo group; RR 1.13 (95% CI 0.4 to 3.17).There was no significant difference in the graft rejections, intensive therapy unit stay, or hospital stay between the intervention and control groups in any of the comparisons. Overall, 193/611 participants (31.6%) developed infective complications. The proportion of people who developed infective complications and the number of infective complication episodes were significantly higher in the selective bowel decontamination group than in the prebiotics with probiotics group (1 study; 63 participants; 15/32 (46.9%) in selective bowel decontamination group versus 4/31 (12.9%) in prebiotics with probiotics group; RR 3.63; 95% CI 1.36 to 9.74 and 23/32 participants (0.72 infective complications per participant) in selective bowel decontamination group versus 4/31 participants (0.13 infective complications per participant) in prebiotics with probiotics group; rate ratio 5.58; 95% CI 1.94 to 16.09). There was no significant difference between the proportion of participants who developed infection and the number of infection episodes between the intervention group and control group in any of the other comparisons.No trials reported quality of life and overall serious adverse events.

AUTHORS' CONCLUSIONS

Currently, there is no clear evidence for any intervention offering significant benefits in the reduction of bacterial infections and wound complications in liver transplantation. Selective bowel decontamination may even increase the rate of infections compared with prebiotics with probiotics. The confidence intervals were wide and further randomised clinical trials of low risk of bias are necessary.

A non-interventional study of the genetic polymorphisms of NOD2 associated with increased mortality in non-alcoholic liver transplant patients

Background

Infections after liver transplantation are the main cause of death in the first year. Recent reports indicate that NOD2 gene mutations increase the risk for inflammatory bowl disease and the severity of graft-versus-host disease in bone marrow transplant patients. Data on polymorphisms in liver transplant patients are sparse. We analyzed 13 single-nucleotide polymorphisms (SNPs) of 13 different gene variants including the SNPs of NOD2 genes from liver recipients. The aim of the study was to evaluate the impact of the SNPs on dialysis-dependent kidney failure, the incidence of infections and patient survival.

Methods

During a period of 20-months, 231 patients were recruited in this non-interventional, prospective study. Thirteen different SNPs and their impact on the patients’ survival, infection rate, and use of dialysis were assessed.

Results

NOD 2 wildtype genes were protective with respect to the survival of non-alcoholic, cirrhotic transplant patients (3 year survival: 66.8% wildtype vs. 42.6% gene mutation, p = 0.026). This effect was not observed in alcoholic transplant recipients.

The incidence of dialysis-dependent kidney failure and infection in the liver transplant patients was not influenced by NOD 2 gene polymorphisms. No effect was noted in the remaining 12 SNPs.

Patients with early allograft dysfunction experienced significantly more infections, required dialysis and had significantly worse survival.

In contrast, the donor-risk-index had no impact on the infection rate, use of dialysis or survival.

Conclusion

NOD2 gene variants seem to play a key role in non-alcoholic, liver transplant recipients. However these data should be validated in a larger cohort.

Recipient's genetic R702W NOD2 variant is associated with an increased risk of bacterial infections after orthotopic liver transplantation

Introduction

Orthotopic liver transplantation (OLT) is accompanied by a significant postoperative infection risk. Immunosuppression to prevent rejection increases the susceptibility to infections, mainly by impairing the adaptive immune system. Genetic polymorphisms in the lectin complement pathway of the donor have recently been identified as important risk determinants of clinically significant bacterial infection (CSI) after OLT. Another genetic factor involved in innate immunity is NOD2, which was reported to be associated with increased risk of spontaneous bacterial peritonitis in cirrhotic patients.

Methods

We assessed association of three genetic NOD2 variants (R702W, G908R and 3020insC) with increased risk of CSI after OLT. 288 OLT recipient-donor pairs from two tertiary referral centers were genotyped for the three NOD2 variants. The probability of CSI in relation to NOD2 gene variants was determined with cumulative incidence curves and log-rank analysis.

Results

The R702W NOD2 variant in the recipient was associated with CSI after OLT. Eight out of 15 (53.3%) individuals with a mutated genotype compared to 80/273 (29.3%) with wild type genotype developed CSI (p=0.027, univariate cox regression), illustrated by a higher frequency of CSI after OLT over time (p=0.0003, log rank analysis). Multivariate analysis (including the donor lectin complement pathway profile) showed independence of this R702W NOD2 association from other risk factors (HR 2.0; p=0.04). The other NOD2 variants, G908R and 3020insC, in the recipient were not associated with CSI. There was no association with CSI after OLT for any of the NOD2 variants in the donor.

Conclusion

The mutated NOD2 R702W genotype in the recipient is independently associated with an increased risk of bacterial infections after liver transplantation, indicating a predisposing role for this genetic factor impairing the recipient’s innate immune system.

Genetic polymorphisms in innate immunity receptors do not predict the risk of bacterial and fungal infections and acute rejection after liver transplantation

INTRODUCTION

We studied the influence of a broad range of genetic variants in recipient and donor innate immunity receptors on bacterial and fungal infections and acute rejection after liver transplantation (LT).

METHODS

Seventy-six polymorphisms in TLR 1-10, NOD2, LBP, CD14, MD2, SIGIRR, Ficolins 1, -2, and -3, MASP 1, -2, and -3, and the complement receptor C1qR1 were determined in 188 LT recipients and 135 of their donors. Associations with clinically significant infections and acute rejection were analyzed for 50 polymorphisms. Significant associations were validated in an independent cohort of 181 recipients and 167 donors.

RESULTS

Three recipient polymorphisms and 3 donor polymorphisms were associated with infections in the identification cohort, but none of these associations were confirmed in the validation cohort. Three donor polymorphisms were associated with acute rejection in the identification cohort, but not in the validation cohort.

CONCLUSION

In contrast to their effect in the general population, 50 common genetic variations in innate immunity receptors do not influence susceptibility to bacterial/fungal infections after LT. In addition, no reproducible associations with acute rejection after LT were observed. Likely, transplant-related factors play a superior role as risk factors for bacterial/fungal infections and acute rejection after LT.

Radiological and clinical findings of 25 patients with invasive pulmonary aspergillosis: retrospective analysis of 2150 liver transplantation cases

OBJECTIVE

The purpose of this study was to evaluate the radiological and clinical findings of invasive pulmonary aspergillosis (IPA) after liver transplantation.

METHODS

This study included 25 consecutive liver transplant recipients with histologically confirmed IPA after liver transplantation. Radiological examinations performed for diagnosis were available in all patients. Clinical findings and changes in clinical response and radiological findings after treatment were also evaluated.

RESULTS

3 main radiological findings were identified: nodules, 64% (16/25); masses, 36% (9/25); and consolidations in a patchy pattern, 20% (5/25). A tree-in-bud pattern was found in 12% (3/25) of patients. In 8 (32%) of 25 patients, we found a combination of 2 or more of these signs: 5 (20%) patients presented with concurrent nodules accompanied by patchy consolidations and/or tree-in-bud, and 3 (12%) patients showed masses accompanied by large consolidations. A halo sign was observed in 20 (80%) of 25 patients. Hypodense sign and cavitary lesions were encountered in 17 (68%) of 25 patients. Follow-up radiological findings after treatment showed improvement in 18 patients, no change in 4 patients and progression in 3 patients. There were three aspergillosis-associated deaths during the follow-up period. The onset time of IPA was a median of 31 days after transplantation. The most common symptom at diagnosis was fever (n=15). None of the 25 patients had leukopaenia at the time of the diagnosis of IPA.

CONCLUSIONS

The most common radiological findings of IPA after liver transplantation are multiple nodules with or without halo sign, masses and consolidations, which usually appear about 1 month after transplantation.

Mortality associated with carbapenem-resistant Klebsiella pneumoniae infections in liver transplant recipients

Resistant bacterial infections are important causes of morbidity and mortality after liver transplantation (LT). This was a retrospective cohort study evaluating the outcomes associated with carbapenem-resistant Klebsiella pneumoniae (CRKP) infections after LT. In a 2005-2006 cohort of 175 consecutive LT recipients, 91 infection episodes were observed in 61 patients (35%). The mortality rate 1 year after LT was 18% (32/175). Enterococcus (43%) and Klebsiella species (37%) were the most frequently isolated bacteria. CRKP infections occurred in 14 patients, and 10 of these patients (71%) died. Seven of these deaths occurred within 30 days of the CRKP infection. The median time to the onset of CRKP infections was 12 days (range = 1-126 days) after LT. The survival rate was significantly lower for patients with a CRKP infection versus patients without a CRKP infection (29% versus 86%, log-rank P < 0.001). In a multivariate analysis, the only pre-LT and post-LT clinical variables significantly associated with death were a Model for End-Stage Liver Disease score ≥ 30 (hazard ratio = 3.4, P = 0.04) and a post-LT CRKP infection (hazard ratio = 4.9, P = 0.007). In conclusion, the outcomes associated with CRKP infections in LT recipients are poor. Because the optimal treatment strategies for CRKP infections remain undefined, improved preventive strategies are needed to curtail the devastating impact of CRKP in LT recipients.

Primary care of the liver transplant recipient

Chronic rejection of liver graft is an insidious process. Major immunosuppression medications such as tacrolimus, cyclosporin, and sirolimus have dose-related toxicity and narrow therapeutic windows. Certain drugs can affect metabolism of calcineurin inhibitors. Primary care physicians should be vigilant for any unusual opportunistic infection in liver transplant recipients. The quality of life of liver transplant recipients is an important aspect of care by primary care physicians. Alcohol relapse and possibility of depression in liver transplant recipients should be a continuous concern for primary care physicians. This article provides a guideline for the care of liver transplant recipients.

Critical care issues in patients after liver transplantation

The majority of patients who undergo liver transplantation (LT) spend some time in the intensive care unit during the postoperative period. For some, this is an expected part of the immediate posttransplant recovery period, whereas for others, the stay is more prolonged because of preexisting conditions, intraoperative events, or postoperative complications. In this review, 4 topics that are particularly relevant to the postoperative intensive care of LT recipients are discussed, with an emphasis on current knowledge specific to this patient group. Infectious complications are the most common causes of early posttransplant morbidity and mortality. The common patterns of infection seen in patients after LT and their management are discussed. Acute kidney injury and renal failure are common in post-LT patients. Kidney injury identification, etiologies, and risk factors and approaches to management are reviewed. The majority of patients will require weaning from mechanical ventilation in the immediate postoperative period; the approach to this is discussed along with the approach for those patients who require a prolonged period of mechanical ventilation. A poorly functioning graft requires prompt identification and appropriate management if the outcomes are to be optimized. The causes of poor graft function are systematically reviewed, and the management of these grafts is discussed.

Intensive care management of liver transplanted patients

Advances in pre-transplant treatment of cirrhosis-related organ dysfunction, intraoperative patient management, and improvements in the treatment of rejection and infections have made human liver transplantation an effective and valuable option for patients with end stage liver disease. However, many important factors, related both to an increasing "marginality" of the implanted graft and unexpected perioperative complications still make immediate post-operative care challenging and the early outcome unpredictable. In recent years sicker patients with multiple comorbidities and organ dysfunction have been undergoing Liver transplantation; appropriate critical care management is required to support prompt graft recovery and prevent systemic complications. Early post-operative management is highly demanding as significant changes may occur in both the allograft and the "distant" organs. A functioning transplanted liver is almost always associated with organ system recovery, resulting in a new life for the patient. However, in the unfortunate event of graft dysfunction, the unavoidable development of multi-organ failure will require an enhanced level of critical care support and a prolonged ICU stay. Strict monitoring and sustainment of cardiorespiratory function, frequent assessment of graft performance, timely recognition of unexpected complications and the institution of prophylactic measures to prevent extrahepatic organ system dysfunction are mandatory in the immediate post-operative period. A reduced rate of complications and satisfactory outcomes have been obtained from multidisciplinary, collaborative efforts, skillful vigilance, and a thorough knowledge of pathophysiologic characteristics of the transplanted liver.

Lectin complement pathway gene profile of donor and recipient determine the risk of bacterial infections after orthotopic liver transplantation

Infectious complications after orthotopic liver transplantation (OLT) are a major clinical problem. The lectin pathway of complement activation is liver-derived and a crucial effector of the innate immune defense against pathogens. Polymorphisms in lectin pathway genes determine their functional activity. We assessed the relationship between these polymorphic genes and clinically significant bacterial infections, i.e., sepsis, pneumonia, and intra-abdominal infection, and mortality within the first year after OLT, in relation to major risk factors in two cohorts from different transplant centers. Single-nucleotide polymorphisms in the mannose-binding lectin gene (MBL2), the ficolin-2 gene (FCN2), and the MBL-associated serine protease gene (MASP2) of recipients and donors were determined. Recipients receiving a donor liver in the principal cohort with polymorphisms in all three components i.e., MBL2 (XA/O; O/O), FCN2+6359T, and MASP2+371A, had a cumulative risk of an infection of 75% as compared to 18% with wild-type donor livers (P = 0.002), an observation confirmed in the second cohort (P = 0.04). In addition, a genetic (mis)match between donor and recipient conferred a two-fold higher infection risk for each separate gene. Multivariate Cox analysis revealed a stepwise increase in infection risk with the lectin pathway gene profile of the donor (hazard ratio = 4.52; P = 8.1 x 10(-6)) and the donor-recipient (mis)match genotype (hazard ratio = 6.41; P = 1.9 x 10(-7)), independent from the other risk factors sex and antibiotic prophylaxis (hazard ratio > 1.7 and P < 0.02). Moreover, patients with a lectin pathway gene polymorphism and infection had a six-fold higher mortality (P = 0.9 x 10(-8)), of which 80% was infection-related.

CONCLUSION

Donor and recipient gene polymorphisms in the lectin complement pathway are major determinants of the risk of clinically significant bacterial infection and mortality after OLT.

Procalcitonin as a prognostic marker for infectious complications in liver transplant recipients in an intensive care unit

Clinically significant infections (CSIs) are life-threatening but difficult to diagnose after liver transplantation (LTx). This study investigates the value of procalcitonin (PCT) in addition to c-reactive protein (CRP) and the leukocyte count (LC) as a prognostic marker for CSIs in LTx recipients. The clinical course of 135 LTx recipients was prospectively studied. CSIs were defined as pulmonary, bloodstream, or intra-abdominal infections. Independent risk factors for CSIs were determined by Cox proportional hazard analysis. The concordance statistics (c-statistics) were used to assess the discrimination effect of PCT. Thirty recipients (22%) experienced a CSI. They had significantly higher peak PCT (27.2 versus 12.7 ng/mL, P = 0.014) and peak CRP (13.7 versus 9.9 mg/dL, P < 0.001) and a tendency toward a higher peak LC (19.3 versus 14.2 cells/nL, P = 0.051) in comparison with recipients without CSIs. Independent risk factors for CSIs were male sex [hazard ratio (HR) = 6.4], a body mass index (BMI) < 20 kg/m(2) (versus a BMI > 25 kg/m(2), HR = 13.8), acute liver failure as an indication for LTx (HR = 7.1), a cold ischemic time > 420 minutes (HR = 3.5), and peak CRP (HR = 1.1) but not peak PCT. The addition of peak PCT marginally improved the c-statistic from 0.815 to 0.827. In conclusion, although peak PCT differed significantly between recipients with and without CSIs, it was not an independent risk factor for CSIs and added little prognostic accuracy. Interestingly, the parameters peak CRP, male sex, low BMI, acute liver failure, and long cold ischemic time were independent risk factors for CSIs. They could serve as risk stratifiers directing medical therapy in clinical practice.

G-CSF in Peg-IFN induced neutropenia in liver transplanted patients with HCV recurrence

AIM: To evaluate the efficacy of granulocyte colony stimulating factors (G-CSF) in liver transplanted patients with hepatitis C (HCV) recurrence and Pegylated-IFN α-2b induced neutropenia, and to evaluate the impact of G-CSF administration on virological response.

METHODS: Sixty-eight patients undergoing antiviral treatment for post-liver transplantation (OLT) HCV recurrence were enrolled. All patients developing neutropenia received G-CSF.

RESULTS: Twenty three (34%) received G-CSF. Mean neutrophil count at the onset of neutropenia was 700/mmc (range 400-750/mmc); after 1 mo of G-CSF it increased to 1210/mmc (range 300-5590/mmc) (P < 0.0001). Three patients did not respond to G-CSF. Treatment duration was similar in neutropenic and non-neutropenic patients. No differences in the rate of discontinuation, infections or virological response were observed between the two groups. G-CSF was protective for the onset of de novo autoimmune hepatitis (P < 0.003).

CONCLUSION: G-CSF administration is effective in the case of Peg-IFN induced neutropenia increasing neutrophil count, prolonging treatment and leading to sustained virological response (SVR) rates comparable to non-neutropenic patients. It prevents the occurrence of de novo autoimmune hepatitis.

Donor mannose-binding lectin deficiency increases the likelihood of clinically significant infection after liver transplantation

BACKGROUND

Mannose-binding lectin (MBL) is an important mediator of innate immunity and is synthesized primarily by the liver. Low MBL levels are common, are due primarily to polymorphisms in the gene encoding MBL (MBL2), and are associated with an increased risk of infection, particularly when immunity is compromised. We report a large, retrospective study that examined the association between MBL status and clinically significant infection following orthotopic liver transplantation.

METHODS

One hundred two donor-recipient orthotopic liver transplantation pairs were studied. Five polymorphisms in the promoter and coding regions of MBL2 were examined. MBL levels were measured, using the mannan-binding and C4-deposition assays, in serum samples obtained before and after transplantation. Associations between MBL status, as assessed by serum MBL levels and MBL2 genotype, and time to first clinically significant infection (CSI) after transplantation were examined in survival analysis with consideration of competing risks.

RESULTS

The median duration of follow-up after orthotopic liver transplantation was 4 years. Thirty-six percent of recipients developed CSI after transplantation. The presence of MBL2 coding mutations in the donor was significantly associated with CSI in the recipient; the cumulative incidence function of infection was 55% in recipients of deficient livers, compared with 32% for recipients of wild-type livers (P = .002). Infection was not associated with recipient MBL2 genotype. Low MBL levels after orthotopic liver transplantation levels (mannan-binding <1 microg/mL or C4 deposition <0.2 C4 U/microL) were also associated with CSI (cumulative incidence function, 52% vs. 20%, P = .003; and cumulative incidence function, 54% vs. 24%, P = .007, respectively). In multivariate analysis, mutation in the MBL2 coding region of the donor (hazard ratio, 2.8; P = .005) and the use of cytomegalovirus prophylaxis (hazard ratio, 2.6; P = .005) were independently associated with CSI.

CONCLUSIONS

Recipients of MBL-deficient livers have almost a 3-fold greater likelihood of developing CSI and may benefit from MBL replacement.