Effect of antibiotic prophylaxis on the risk of surgical site infection in orthotopic liver transplant

Surgical site infections are common bacterial infections in orthotopic liver transplantation. The purpose of this study was to determine the incidence, timing, location, and risk factors, specifically antibiotic prophylaxis, for surgical site infections. A prospective study was performed that included a population of 1222 consecutive patients (73.0% males) who underwent liver transplantation in Spanish hospitals belonging to the Red de Estudio de la Infección en el Trasplante research network. One hundred seven patients developed surgical site infections. The predominant infection sites were incisional wound (53 episodes) and peritonitis (40 episodes). The timing of the organ/space surgical site infections was slightly delayed in comparison with incisional surgical site infections. Enterococcus spp., Escherichia coli, Staphylococcus aureus, and Acinetobacter baumannii were the predominant pathogens. Choledochojejunal or hepaticojejunal reconstruction (odds ratio, 4.2; 95% confidence interval, 1.6-10.7), previous liver or kidney transplant (odds ratio, 2.6; 95% confidence interval, 1.1-6.3), and more than 4 red blood cell units transfused (odds ratio, 2.0; 95% confidence interval, 1.1-3.4) were independently associated with the development of surgical site infections. Biliary reconstruction by choledochojejunostomy or hepaticojejunostomy increases the risk of surgical site infections.

Incidence, clinical characteristics and risk factors of late infection in solid organ transplant recipients: data from the RESITRA study group

Information describing the incidence and clinical characteristics of late infection (LI) in solid organ transplantation (SOT) is scarce. The aim of this study was to define the incidence, clinical characteristics and risk factors for LI (>6 months) as compared with infection in the early period (<6 months) after SOT. By the online database of the Spanish Network of Infection in Transplantation (RESITRA) we prospectively analyzed 2702 SOT recipients from September 2003 to February 2005. Univariate and multivariate analysis using logistic regression were performed to calculate the risk factors associated with the development of LI. A total of 131 patients developed 176 LI episodes (8%). Global incidence of LI was 0.4 per 1000 transplant-days, ranging from 0.3/1000 in kidney transplants to 1.4 in lung transplants. Independent risk factors for LI in were: acute rejection in the early period (OR 1.5; CI 95%: 1.1-2.3), chronic graft malfunction (OR 2; CI 95%: 1.4-3), re-operation (OR 1.9; CI 95%: 1.3-2.8) relapsing viral infection apart from CMV (OR 1.9; CI 95%: 1.1-3.5), previous bacterial infection (OR 1.8; CI 95%: 1.2-2.6) and lung transplantation (OR 4.5; CI 95%: 2.6-7.8). Severe LI occurs in a subgroup of high-risk SOT recipients who deserve a more careful follow-up and could benefit from prolonged prophylactic measures similar to that performed in the early period after transplantation.

A review of critical periods for opportunistic infection in the new transplantation era

BACKGROUND

The risk of opportunistic infection (OI) is considered to be maximum during the first six months after solid organ transplantation. The aim of this study was to know the incidence and risk factors for OI in the late period (>6 months) compared with the early period (<6 months) after solid organ transplantation.

METHODS

We used the online database of the Spanish Network of Infection in Transplantation (RESITRA), which prospectively analyzed 2,702 solid organ transplantation recipients from August 2003 to February 2005. Univariate and multivariate analyses were performed to calculate the risk factors associated with the development of late OI.

RESULTS

A total of 131 patients (6%) developed 176 infectious episodes in the late period. Although the incidence of infection and cytomegalovirus disease (0.4 per 1000 transplant days and 0.05 per 1000 transplant days, respectively) was lower than in the early period (3.5 per 1000 transplant days and 0.8 per 1000 transplant days; P<0.0001), the incidence of other OIs was similar in both periods (0.05 per 1000 transplant days versus 0.03 per 1000 transplant-days, P=0.5). Patients with the higher risk for developing late OI were those receiving early cytomegalovirus prophylaxis, patients who developed two or more episodes of acute rejection during the early period, patients with recurrent bacterial infection during the early period, patients with renal failure requiring dialysis, and patients with chronic graft malfunction.

CONCLUSIONS

Our data suggest that in some high-risk patients, the critical period of risk for OI must be expanded beyond the first six months after transplant.

Cytomegalovirus in transplantation ? challenging the status quo

BACKGROUND

Cytomegalovirus (CMV) infection of solid organ transplant (SOT) recipients causes both ''direct'' and ''indirect'' effects including allograft rejection, decreased graft and patient survival, and predisposition to opportunistic infections and malignancies. Options for CMV prevention include pre-emptive therapy, whereby anti-CMV agents are administered based on sensitive viral assays, or universal prophylaxis of all at-risk patients. Each approach has advantages and disadvantages in terms of efficacy, costs, and side effects. Standards of care for prophylaxis have not been established.

METHODS

A committee of international experts was convened to review the available data regarding CMV prophylaxis and to compare preventative strategies for CMV after transplantation from seropositive donors or in seropositive recipients.

RESULTS

Pre-emptive therapy requires frequent monitoring with subsequent treatment of disease and associated costs, while universal prophylaxis results in greater exposure to potential toxicities and costs of drugs. The advantages of prophylaxis include suppressing asymptomatic viremia and prevention of both direct and indirect effects of CMV infection. Meta analyses reveal decreased in mortality for patients receiving CMV prophylaxis. Costs associated with prophylaxis are less than for routine monitoring and pre-emptive therapy. The optimal duration of antiviral prophylaxis remains undefined. Extended prophylaxis may improve clinical outcomes in the highest-risk patient populations including donor-seropositive/recipient-seronegative renal transplants and in CMV-infected lung and heart transplantation.

CONCLUSIONS

Prophylaxis is beneficial in preventing direct and indirect effects of CMV infection in transplant recipients, affecting both allograft and patient survival. More studies are necessary to define optimal prophylaxis regimens.

Survival and prognostic factors of HIV-infected patients with HCV-related end-stage liver disease

OBJECTIVE

To find the survival and the predictors of death of HIV-infected patients with hepatitis C virus (HCV)-related end-stage liver disease (ESLD).

DESIGN AND METHODS

A prospective cohort study set in the infectious diseases units of four tertiary care public hospitals in Andalucía, Spain. From a multicentric cohort of 2664 HIV/HCV-co-infected patients, all consecutive patients with HCV-related cirrhosis who presented with the first hepatic decompensation from January 1997 to June 2004 were followed-up and 153 patients were included. The survival and the demographic, HIV-related and liver-related factors associated with death were evaluated.

RESULTS

Ninety-five (62%) patients died during the follow-up. In 79 (85%) individuals, the cause of death was liver related. The median survival time was 13 months. Independent predictors of survival were Child score [hazard ratio (HR), 1.2; 95% confidence interval (CI), 1.08-1.37; P = 0.001], CD4+ cell count at decompensation lower than 100 cells/microl (HR, 2.48; 95% CI, 1.52-4.06; P < 0.001) and hepatic encephalopathy as the first hepatic decompensation (HR, 2.45; 95% CI, 1.41-4.27; P = 0.001). HAART was prescribed to 101 (66%) patients. The cumulative probability of survival in patients under HAART was 60% at 1 year and 40% at 3 years, versus 38 and 18%, respectively, in patients not treated with HAART (P < 0.0001). The HR (95% CI) of death in patients on HAART was 0.5 (0.3-0.9), (P = 0.03). CONCLUSIONS The survival of HIV/HCV-co-infected patients with ESLD is extremely poor. Immunosuppression and markers of severe liver disease predict liver-related mortality in these patients. HAART seems to be associated with a reduced liver-related mortality.

Resistance to Nonnucleoside Reverse-Transcriptase Inhibitors and Prevalence of HIV Type 1 Non-B Subtypes Are Increasing among Persons with Recent Infection in Spain

The prevalence of drug resistance mutations was 12.1% among 198 persons who experienced human immunodeficiency virus (HIV) seroconversion identified in Spain during 1997-2004. There was a significant increase of K103N and of non-B subtypes over time. Transmission of HIV infection around the time of seroconversion was shown in 8 couples and in 2 clusters of 3 individuals.

Infliximab does not activate replication of lymphotropic herpesviruses in patients with refractory rheumatoid arthritis

OBJECTIVE

The reactivation of human lymphotropic herpesviruses can be related to the intensity of immunosuppression. We analysed the risk of reactivation of lymphotropic herpesviruses in patients with refractory rheumatoid arthritis treated with an anti-tumour necrosis factor-alpha (TNF-alpha) agent (infliximab).

METHODS

Fifteen patients were treated with infliximab (3 mg/kg) at weeks 0, 2 and 6. Samples of both plasma and peripheral blood mononuclear cells (PBMC) were obtained before treatment (week 0) and before each infusion at weeks 2 and 6. Samples were analysed using a multiplex qualitative polymerase chain reaction (PCR) for lymphotropic herpesviruses. Quantification of cytomegalovirus (CMV) viral load (copies/ml) was performed using quantitative PCR. Reactivation was defined as the presence of viral DNA in plasma. Latent infection was defined as the presence of viral DNA in PBMC samples but not in plasma.

RESULTS

On baseline, latent CMV infection was detected in eight patients (53.3%), human herpesviruses-6 (HHV-6) in two (13.3%), Epstein-Barr virus (EBV) in seven (46.6%), CMV + HHV-6 in one (6.6%), CMV + EBV in two (13.3%) and HHV-6 + EBV in one (6.6%). Viral reactivation related to infliximab treatment was not observed. There was only one patient who had HHV-6 reactivation, but this was already detected in the baseline sample.

CONCLUSIONS

Infliximab treatment does not induce replication of human lymphotropic herpesviruses in patients with rheumatoid arthritis. Thus, herpesviruses prophylaxis would not be indicated in these patients.

Risk factors for invasive aspergillosis in solid-organ transplant recipients: a case-control study

BACKGROUND

To facilitate the design of strategies for prevention of invasive aspergillosis in solid-organ transplant recipients, this study investigates whether the development of early-onset and late-onset aspergillosis are related to different risk factors, thereby distinguishing 2 risk populations for this serious complication.

METHODS

A retrospective case-control study was performed, including 156 cases of proven or probable invasive aspergillosis in patients recruited from 11 Spanish centers since the start of the centers' transplantation programs.

RESULTS

Among all patients, 57% had early-onset IA (i.e., occurred during the first 3 months after transplantation). Risk factor analysis in this group identified as significantly associated risk factors a more complicated postoperative period, repeated bacterial infections or cytomegalovirus disease, and renal failure or the need for dialysis. Among patients with late-onset infections (i.e., occurred > 3 months after transplantation), who comprised 43% of cases, the patients at risk were older, were in an overimmunosuppressed state because of chronic transplant rejection or allograft dysfunction, and had posttransplantation renal failure.

CONCLUSIONS

Risk factors in patients with early-onset cases and patients with late-onset cases of posttransplantation invasive aspergillosis are not the same, a fact that could have implications for the preventive approaches used for this infection.

HAART induces the expression of HLA-G on peripheral monocytes in HIV-1 infected individuals

The aim of this work is to analyze if the highly active antiretroviral therapy (HAART) has any effect in the number of peripheral monocytes expressing the tolerogenic molecule human leukocyte antigen G (HLA-G) in HIV-1 infected individuals. In this sense, expression of HLA-G was measured by flow cytometry on peripheral monocytes from HIV-1 antiretroviral-receiving and antiretroviral naïve patients and in HIV-1 patients at different times after the antiretroviral treatments were removed. It was found an increment of monocytes expressing HLA-G in HIV-1 infected individuals receiving HAART, whereas monocytes from untreated HIV-1 patients did not change. When the HLA-G was measured on monocytes after antiretroviral treatment was removed, the number of peripheral monocytes expressing HLA-G was progressively decreasing. These data suggest that antiretroviral therapy is able to induce the expression of the tolerogenic molecule HLA-G on peripheral monocytes from HIV-1 seropositive individuals.

TUBERCULOSIS IN THE TRANSPLANT CANDIDATE: IMPORTANCE OF EARLY DIAGNOSIS AND TREATMENT

BACKGROUND

Transplantation is contraindicated in candidates with active tuberculosis. The present study was undertaken to determine the clinical manifestations of tuberculosis in the transplant candidate and the prognosis of cases that inadvertently undergo transplantation.

METHODS

This study was a retrospective study of tuberculosis cases diagnosed among 3,889 transplant candidates. All cases were diagnosed from respiratory or tissue samples obtained in the pretransplant period or during transplantation.

RESULTS

We observed 7 cases (0.18%) of active tuberculosis among 3,889 candidates. Two patients had a history of tuberculosis. Tuberculosis was frequently asymptomatic. Three patients had extrapulmonary tuberculosis. Chest radiographs showed residual fibrotic lesions in three patients and noncavitated consolidation in two patients. All of the patients in which the purified protein derivative test was performed were anergic. All patients that inadvertently underwent transplantation were cured.

CONCLUSIONS

Aggressive management is required to prevent tuberculosis in transplant candidates. Patients that inadvertently undergo transplantation can be effectively treated when diagnosed early.

Frequency of visceral leishmaniasis relapses in human immunodeficiency virus-infected patients receiving highly active antiretroviral therapy

There are contradictory data about whether highly active antiretroviral therapy (HAART) prevents visceral leishmaniasis (VL) relapses in human immunodeficiency virus type 1 (HIV-1)-infected patients. The aim of this study was to assess the frequency of VL relapses in individuals receiving HAART. Thirty-one patients who received HAART after developing VL were included in a retrospective cohort study. Ten of them received secondary chemoprophylaxis and the rest did not. Eight (38%) patients without secondary chemoprophylaxis showed a VL relapse. None of the seven subjects with VL relapses and 6 of 11 without recurrence (P = 0.038), in whom all scheduled data were available, showed an increase of more than 100 CD4+ cells/mm(3) during the follow-up. Patients with relapse showed higher levels of HIV RNA viral load at their last visit (P = 0.047). The frequency of VL relapses in patients receiving HAART is high. Relapses of VL are observed only in individuals with uncontrolled HIV replication and/or poor immunologic responses.

Consensus conference on chronic viral hepatitis and HIV infection: updated Spanish recommendations

Chronic hepatitis B and C represent a leading cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected patients worldwide. New treatment options against both hepatitis B (HBV) and C (HCV) viruses have prompted us to update previous recommendations for the management of coinfected individuals. Fifteen topics (nine related to HCV, five to HBV and one to both viruses) were selected for this purpose. A panel of Spanish experts in the field was invited to review these areas and propose specific recommendations, which were scored according to the Infectious Disease Society of America (IDSA) grading system. These guidelines represent a comprehensive and updated overview on the management of hepatitis B and C in HIV-infected patients.

Pre-emptive oral ganciclovir can reduce the risk of cytomegalovirus disease in liver transplant recipients

A cohort of 65 liver transplant recipients was prospectively monitored with qualitative polymerase chain reaction (PCR) in plasma. The first 25 patients did not receive prophylaxis. From a consecutive group of 40 recipients, 11 high-risk patients donor CMV-seropositive/receptor CMV-seronegative (D+/R-), persistent CMV replication) received pre-emptive oral ganciclovir (1000 mg three times daily), when a marker of risk was identified, until day 90. The overall incidence of cytomegalovirus (CMV) disease at six months was 20% (five of 25 patients) in the non-prophylaxis group and 2.5% (one of 40 patients) in the group treated with pre-emptive oral ganciclovir (relative risk, 0.11; 95% confidence interval; 0.01-0.96; P = 0.04). The PCR sensitivity for detecting CMV disease was 80%, the specificity was 90%, and the positive and negative predictive values were 66% and 95%, respectively. Adverse events, graft rejection and survival were similar between groups. We conclude that pre-emptive oral ganciclovir in high-risk patients can reduce the risk of CMV disease.

Selective depletion of CD56(dim) NK cell subsets and maintenance of CD56(bright) NK cells in treatment-naive HIV-1-seropositive individuals

Human immunodeficiency virus-I (HIV-1) infected patients show a gradual loss of natural killer (NK) cells that correlates with disease progression. However, the effect of HIV-1 infection on different NK cell subsets has not been fully characterized. In healthy individuals most NK cells are CD3-CD56+ and two different subpopulations, CD56(dim) and CD56(bright), can be distinguished by the mean fluorescence intensity. Although it was originally suggested that CD56(bright) NK cells represent the precursors of the CD56dim subpopulation, recent cumulative data indicate that CD56(bright) and CD56(dim) NK cells are phenotypically, functionally, and developmentally different NK cell subsets. In this study, the analysis of CD56(bright) and CD56(dim) NK subsets showed that neither the number nor the phenotype of CD56(bright) NK cells were significantly altered in treatment-naive HIV-1-infected individuals, whereas the number of CD56(dim) NK cells was decreased. We also have studied NK cell subsets defined by the expression of CD56 in combination with CD16, CD161, or CD94 molecules. Our results demonstrated a preferential decrease of CD3-CD56+ NK cells coexpressing CD16 and CD161 but lacking CD94 molecules. On the contrary an increased percentage of NK cells that do not express CD56 molecules but express CD16, CD161, or CD94 was also found in HIV-1-infected individuals. As it has been proposed that these CD56-negative NK cells expressing other NK cell receptors represent immature NK cells with low cytolytic capacity, our results support that a defective differentiation from immature CD56 negative NK cells to mature CD56(dim) NK cells occurs in HIV-1 infection.

High mortality related with Staphylococcus aureus bacteremia after liver transplantation

The aim of the present study was to analyze the characteristics of bacteremia occurring in liver-transplant patients in Andalusia, Spain, during the 1990s. At the three participating hospitals, 405 liver transplantations were performed during the study period, and 119 bacteremic episodes were observed following 91 of them (22.4%, 29.4 episodes/100 liver transplants). Gram-positive organisms were the predominant bacteria isolated in cases of early-onset bacteremia (70.7%, P=0.04). The most common sources of bacteremia were the abdomen (33.6%) and intravascular catheters (22.7%), but frequently the source of bacteremia was unknown (31.9%). Mortality at 30 days was 21%. Isolation of Staphylococcus aureus was the only independent risk factor for mortality (relative risk, 3.13; 95% confidence interval, 1.3-7.5; P=0.01). These results indicate that control measures are required in order to reduce the incidence of gram-positive bacteremia and catheter-related infection in this patient population. The observed etiology must be considered when empirical antimicrobial therapy is indicated while awaiting blood-culture results.

Impact of highly active antiretroviral therapy on fever of unknown origin in HIV-infected patients

In order to assess the impact of highly active antiretroviral therapy (HAART) on the frequency and etiology of fever of unknown origin in HIV-infected patients, a retrospective study was performed on cases of fever of unknown origin observed from January 1997 to December 1999 in seven hospitals in five cities in Andalusia, Spain. During the period specified, a total of 4,858 HIV-infected patients receiving HAART and 2,787 HIV-infected individuals not receiving HAART were studied. The frequency of fever of unknown origin was 0.6% in patients receiving HAART and 3% in non-HAART patients (P=0.001). Human immunodeficiency virus infection was the only cause of fever found more frequently in the non-HAART patient group (P=0.07). The study findings suggest that the use of HAART has reduced the frequency of fever of unknown origin in HIV-infected patients, but the etiology of the condition remains mostly unchanged.

Factors associated with the development of post-transplant lymphoproliferative disease (PTLD) in Epstein-Barr virus (EBV)-seronegative adult liver transplant recipients

Epstein-Barr virus (EBV) infection is recognized as the principal aetiological factor in the pathogenesis of post-transplant lymphoproliferative disease (PTLD), particularly when primary EBV infection occurs after transplantation. We analysed, using a time-dependent proportional hazards model, the factors associated with development of PTLD in 40 adult liver transplant recipients who were seronegative for EBV prior to transplantation. Of 40 patients, 13 (33%) had a tissue diagnosis of PTLD at a median time of 126 days after transplantation. The multivariate analysis showed that prior CMV disease, the number of steroid boluses given and the number of units of RBC and FFP transfused were significant risk factors for development of PTLD.