Carbapenem-resistant Acinetobacter baumannii acquired before liver transplantation: Impact on recipient outcomes.

Infection with carbapenem-resistant Acinetobacter baumannii (CRAB) after liver transplantation (LT) is associated with high mortality. This study aimed to identify risk factors for post-LT CRAB infection, as well as to evaluate the impact of pre-LT CRAB acquisition on the incidence of post-LT CRAB infection. This was a prospective cohort study of all patients undergoing LT at our facility between October 2009 and October 2011. Surveillance cultures (SCs) were collected immediately before LT and weekly thereafter, until discharge. We analyzed 196 patients who were submitted to 222 LTs. CRAB was identified in 105 (53.6%); 24 (22.9%) of these patients were found to have acquired CRAB before LT, and 85 (81.0%) tested positive on SCs. Post-LT CRAB infection occurred in 56 (28.6%), the most common site being the surgical wound. Multivariate analysis showed that the risk factors for developing CRAB infection were prolonged cold ischemia, post-LT dialysis, LT due to fulminant hepatitis, and pre-LT CRAB acquisition with pre-LT CRAB acquisition showing a considerable trend toward significance (P = 0.06). Among the recipients with CRAB infection, 60-day mortality was 46.4%, significantly higher than among those without (P < 0.001). Mortality risk factors were post-LT infection with multidrug-resistant bacteria, LT performed because of fulminant hepatitis, retransplantation, prolonged cold ischemia, longer LT surgical time, and pre-LT CRAB acquisition, the last showing a trend toward significance (P = 0.08). In conclusion, pre-LT CRAB acquisition appears to increase the risk of post-LT CRAB infection, which has a negative impact on recipient survival. Liver Transplantation 22 615-626 2016 AASLD.

Quantification of C4d deposition and hepatitis C virus RNA in tissue in cases of graft rejection and hepatitis C recurrence after liver transplantation.

Histology is the gold standard for diagnosing acute rejection and hepatitis C recurrence after liver transplantation. However, differential diagnosis between the two can be difficult. We evaluated the role of C4d staining and quantification of hepatitis C virus (HCV) RNA levels in liver tissue. This was a retrospective study of 98 liver biopsy samples divided into four groups by histological diagnosis: acute rejection in patients undergoing liver transplant for hepatitis C (RejHCV+), HCV recurrence in patients undergoing liver transplant for hepatitis C (HCVTx+), acute rejection in patients undergoing liver transplant for reasons other than hepatitis C and chronic hepatitis C not transplanted (HCVTx-). All samples were submitted for immunohistochemical staining for C4d and HCV RNA quantification. Immunoexpression of C4d was observed in the portal vessels and was highest in the HCVTx- group. There was no difference in C4d expression between the RejHCV+ and HCVTx+ groups. However, tissue HCV RNA levels were higher in the HCVTx+ group samples than in the RejHCV+ group samples. Additionally, there was a significant correlation between tissue and serum levels of HCV RNA. The quantification of HCV RNA in liver tissue might prove to be an efficient diagnostic test for the recurrence of HCV infection.

Surgical site infections in liver transplant recipients in the model for end-stage liver disease era: an analysis of the epidemiology, risk factors, and outcomes.

In recipients of liver transplantation (LT), surgical site infection (SSIs) are among the most common types of infection occurring in the first 60 days after LT. In 2007, the Model for End-Stage Liver Disease (MELD) scoring system was adopted as the basis for prioritizing organ allocation. Patients with higher MELD scores are at higher risk for developing SSIs as well as other health care-associated infections. However, there have been no studies comparing the incidence of SSIs in the pre-MELD era with the incidence in the period since its adoption. Therefore, the objectives of this study were to evaluate the incidence, etiology, epidemiology, and outcomes of post-LT SSIs in those 2 periods and to identify risk factors for SSIs. We evaluated all patients who underwent LT over a 10-year period (2002-2011). SSI cases were identified through active surveillance. The primary outcome measure was an SSI during the first 60 days after LT. Risk factors were analyzed via logistic regression, and 60-day survival rates were evaluated via Cox regression. We evaluated 543 patients who underwent LT 597 times. The SSI rates in the 2002-2006 and 2007-2011 periods were 30% and 24%, respectively (P = 0.21). We identified the following risk factors for SSIs: retransplantation, the transfusion of more than 2 U of blood during LT, dialysis, cold ischemia for >400 minutes, and a cytomegalovirus infection. The overall 60-day survival rate was 79%. Risk factors for 60-day mortality were retransplantation, dialysis, and a longer surgical time. The use of the MELD score modified the incidence and epidemiology of SSIs only during the first year after its adoption. Risks for SSIs were related more to intraoperative conditions and intercurrences after LT than to a patient's status before LT.

Applying mucosal barrier injury laboratory-confirmed bloodstream infection criteria in patients with solid tumors and hematologic malignancies: A retrospective cohort study looking for the real source of infection.

We evaluated the interference of the mucosal barrier injury (MBI) laboratory-confirmed bloodstream infection (MBI-LCBI) criteria on the central-line-associated bloodstream infection (CLABSI) incidence density, and the proportion of catheter-related bloodstream infections (CRBSIs) among those classified as MBI. We detected 339 CLABSIs: 15.0% were classified as MBI-LCBIs, and among these, 19.6% were classified as CRBSIs.

Liver transplant from Anti-HBc-positive, HBsAg-negative donor into HBsAg-negative recipient: is it safe? A systematic review of the literature.

INTRODUCTION: After liver transplant (LT) from Anti-HBc+/HBsAg- donors into HBsAg- recipients, transmission of hepatitis B virus (HBV) may occur (de novo HBV infection). This study analyzes the incidence of de novo HBV infection in HBsAg- recipients of Anti-HBc+/HBsAg- LT with respect to: (i) the recipients' HBV serology and (ii) the type of preventive therapy adopted. METHODS: A systematic review of the literature using the electronic database Medline. RESULTS: Five hundred and fifty-two LT in 36 articles were selected. Lamivudine, Hepatitis B immune globulin (HBIG), revaccination, and combined therapies were employed in multiple strategies as preventive interventions. Naïve recipients had a high risk of de novo HBV infection, with smaller incidences when HBIG and lamivudine were used, either alone or in association. Vaccinated recipients or those with isolated hepatitis B core antibodies (Anti-HBc) and previous HBV infection had lower risks of viral transmission, additionally reduced by any prophylaxis adoption. DISCUSSION: LT from Anti-HBc+/HBsAg- donors into HBsAg- recipients is apparently safe, as long as the recipient is vaccinated or presents an isolated Anti-HBc or previous HBV infection and some prophylaxis is employed. Currently lamivudine seems the best alternative; other nucleoside analogs and revaccination strategies should be considered in future studies. Follow-up and preventive therapies should be maintained for five yr or preferably throughout the recipients' life span.

Surveillance culture for multidrug-resistant gram-negative bacteria: Performance in liver transplant recipients.

BACKGROUND: The prevalence of infection with multidrug-resistant gram-negative bacteria (MDR-GNB) after solid-organ transplantation is increasing. Surveillance culture (SC) seems to be an important tool for MDR-GNB control. The goal of this study was to analyze the performance of SC for MDR-GNB among liver transplant (LT) recipients. METHODS: This was a prospective cohort study involving patients who underwent LT between November 2009 and November 2011. We screened patients for extended spectrum ß-lactamase-producing Escherichia coli, extended spectrum ß-lactamase-producing Klebsiella pneumoniae, and carbapenem-resistant Enterobacteriaceae, carbapenem-resistant Pseudomonas aeruginosa (CRPA), and carbapenem-resistant Acinetobacter baumannii (CRAB). We collected SC samples immediately before LT and weekly thereafter, until hospital discharge. Samples were collected from the inguinal-rectal area, axilla, and throat. The performance of SC was evaluated through analysis of its sensitivity, negative predictive value, and accuracy. RESULTS: During the study period, 181 patients were evaluated and 4,110 SC samples were collected. The GNB most often identified was CRAB, in 45.9% of patients, followed by CRKP in 40.3%. For all microorganisms, the positivity rate was highest among the inguinal-rectal samples. If only samples collected from this area were considered, the SC would fail to identify 34.9% of the cases of CRAB colonization. The sensitivity of SC for CRKP was 92.5%. The performance of SC was poorest for CRAB (sensitivity, 80.6%). CONCLUSIONS: Our data indicate that SC is a sensitive tool to identify LT recipients colonized by MDR-GNB.

Does mycophenolate mofetil increase the risk of cytomegalovirus infection in solid organ transplant recipients?--A mini-review.

Mycophenolate mofetil (MMF) is currently used for prophylaxis of acute rejection in solid organ transplantation. There have been diverging reports regarding an association between MMF and the risk of cytomegalovirus (CMV) infection. We reviewed the main published studies in an attempt to clarify the association between the use of MMF and the risk, frequency and severity of CMV infections. In a search of the Medline database with the terms "mycophenolate" and "cytomegalovir*", 42 articles were found to be relevant; among these, 29 articles were thoroughly analyzed. The first studies on MMF in renal transplantation already showed a tendency towards an association between this drug and the occurrence of CMV disease. Further studies were designed specifically to study this association; with the conclusion that an immunosuppressive regimen containing MMF increases the likelihood of CMV disease. Most studies were performed with kidney transplant recipients. We conclude that the use of MMF apparently increases the incidence of CMV disease in renal transplant patients; however, further studies are needed to confirm this association.

Quantification of C4d deposition and hepatitis C virus RNA in tissue in cases of graft rejection and hepatitis C recurrence after liver transplantation

Histology is the gold standard for diagnosing acute rejection and hepatitis C recurrence after liver transplantation. However, differential diagnosis between the two can be difficult. We evaluated the role of C4d staining and quantification of hepatitis C virus (HCV) RNA levels in liver tissue. This was a retrospective study of 98 liver biopsy samples divided into four groups by histological diagnosis: acute rejection in patients undergoing liver transplant for hepatitis C (RejHCV+), HCV recurrence in patients undergoing liver transplant for hepatitis C (HCVTx+), acute rejection in patients undergoing liver transplant for reasons other than hepatitis C and chronic hepatitis C not transplanted (HCVTx-). All samples were submitted for immunohistochemical staining for C4d and HCV RNA quantification. Immunoexpression of C4d was observed in the portal vessels and was highest in the HCVTx- group. There was no difference in C4d expression between the RejHCV+ and HCVTx+ groups. However, tissue HCV RNA levels were higher in the HCVTx+ group samples than in the RejHCV+ group samples. Additionally, there was a significant correlation between tissue and serum levels of HCV RNA. The quantification of HCV RNA in liver tissue might prove to be an efficient diagnostic test for the recurrence of HCV infection.

Does mycophenolate mofetil increase the risk of cytomegalovirus infection in solid organ transplant recipients? - A mini-review

Mycophenolate mofetil (MMF) is currently used for prophylaxis of acute rejection in solid organ transplantation. There have been diverging reports regarding an association between MMF and the risk of cytomegalovirus (CMV) infection. We reviewed the main published studies in an attempt to clarify the association between the use of MMF and the risk, frequency and severity of CMV infections. In a search of the Medline database with the terms "mycophenolate" and "cytomegalovir*", 42 articles were found to be relevant; among these, 29 articles were thoroughly analyzed. The first studies on MMF in renal transplantation already showed a tendency towards an association between this drug and the occurrence of CMV disease. Further studies were designed specifically to study this association; with the conclusion that an immunosuppressive regimen containing MMF increases the likelihood of CMV disease. Most studies were performed with kidney transplant recipients. We conclude that the use of MMF apparently increases the incidence of CMV disease in renal transplant patients; however, further studies are needed to confirm this association.