Infection frequency and profile in different age groups of kidney transplant recipients

BACKGROUND: Older transplant recipients have been shown to be at greater risk for infectious death than younger adults, but no study to date has looked at relative risk of infection and infection profile differences for children versus adults, which may be very different from one another. METHODS: Data from primary Medicare renal transplant recipients between 1991 and 1998 (n=64,751), as reported in the United States Renal Data System (USRDS), were analyzed for Medicare claims (both inpatient and outpatient) for infection and type of infection in the first year posttransplant. Cox regression was used to model adjusted hazard ratios (AHR) for infection. RESULTS: Total infections among renal transplant recipients increased significantly in more recent years. Patients transplanted in or after 1995 had a significantly higher adjusted risk for infection compared to those transplanted earlier (AHR 1.34, 95% CI=1.29-1.39). Older adults > or = 51 years of age had the highest percentage of experiencing infection, as compared to adults between 18-50 years and children < or = 17 years (P<0.001). Children were at highest risk of viral infection prior to 1995 but at lowest risk of viral infection after 1995, whereas elderly adults were at highest risk of bacterial infection throughout the study. Children experienced more claims for viral infections, whereas older transplant recipients experienced more claims for bacterial infections. CONCLUSIONS: The two extremes of transplant recipient age display very different risks for infection claim frequency and profile.     

Younger Age and Antibody Induction Increase the Risk for Infection in Pediatric Renal Transplantation: A NAPRTCS Report

Infections now exceed rejection as a cause of hospitalization in the first 2 years post-renal transplantation. We analyzed data from the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS) to determine risks for hospitalization for infection (HI), either bacterial (HBI) or viral (HVI). 3106 children transplanted between 1996 and 2002 with 2-year follow-up were analyzed. Univariate and multivariate logistic regression analyses identified factors for cause-specific hospitalization. Results: 23.4% experienced HBI, 23.9% HVI; 8.9% were hospitalized for both. Children 0-1 years age at transplant had higher rates of HI (64.2%), HBI (40.3%) and HVI (43.3%) compared to >12 years (31%, 17.5% and 18.9%, p < 0.0001). In comparison to no induction, patients receiving monoclonal or polyclonal antibody were more likely to have HI (>42% vs. 34.0%), HBI (>24% vs. 21%) or HVI (>29% vs. 21%, all p < 0.003) but had equivalent graft survival (p = NS). Higher rates of HI, HBI and HVI were also seen with prophylactic antimicrobial use and with >5 transfusions pretransplant. Since antibody induction in recent era was not associated with better graft or patient survival but was associated with more HI and HVI, the need for routine antibody induction in children needs to be reassessed.     

Hospitalized avascular necrosis after renal transplantation in the United States

BACKGROUND: The national incidence of and risk factors for hospitalized avascular necrosis (AVN) in renal transplant recipients has not been reported. METHODS: This historical cohort study consisted of 42,096 renal transplant recipients enrolled in the United States Renal Data System (USRDS) between 1 July 1994 and 30 June 1998. The data source was USRDS files through May 2000. Associations with hospitalizations for a primary diagnosis of AVN (ICD-9 codes 733.4x) within three years after renal transplant were assessed in an intention-to-treat design by Cox regression analysis. RESULTS: Recipients had a cumulative incidence of 7.1 episodes/1000 person-years from 1994 to 1998. The two-year incidence of AVN did not change significantly over time. Eighty-nine percent of the cases of AVN were due to AVN of the hip (733.42) and 60.2% of patients with AVN underwent total hip arthroplasty (THA); these percentages did not change significantly over time. In the Cox regression analysis, an earlier year of transplant, African American race [adjusted hazard ratio (AHR), 1.65, 95% confidence interval (CI) 1.33 to 2.03], allograft rejection (AHR 1.67, 95% CI 1.35 to 2.07), peritoneal dialysis (vs. hemodialysis; AHR 1.44, 95% CI 1.15 to 1.81), and diabetes (AHR 0.41, 95% CI 0.27 to 0.64) were the only factors independently associated with hospitalizations for AVN. CONCLUSIONS: The incidence of AVN did not decline significantly over time in the renal transplant population. Patients with allograft rejection, African American race, peritoneal dialysis and earlier date of transplant were at the highest risk of AVN, while diabetic recipients were at a decreased risk.     

AZA/Tacrolimus Is Associated with Similar Outcomes as MMF/Tacrolimus among Renal Transplant Recipients

There have been several retrospective studies indicating benefits associated with mycophenalate mofetil (MMF) compared to azathioprine (AZA) for renal transplant recipients. However, these analyses evaluated outcomes prior to changes in utilization patterns of concomitant immunosuppression. Recent prospective trials have indicated similar outcomes among patients treated with MMF and AZA. The aim of this study was to evaluate outcomes in a broad group of patients in the more recent era. We evaluated adult solitary renal transplant recipients from 1998 to 2006 with the national SRTR database. Primary outcomes were time to patient death and graft loss, complications and renal function. Models were adjusted for potential confounding factors, propensity scores and stratified between higher/lower risk transplants and concomitant immunosuppression. Adjusted models indicated a modest risk among AZA patients for graft loss (AHR = 1.14, 95% CI 1.07–1.20); however, this was not apparent among AZA patients also treated with tacrolimus (AHR = 0.97, 95% CI 0.85–1.11]. One-year acute rejection rates were reduced for patients on MMF versus AZA (10 vs. 13%, p < 0.01); there were no statistically significant differences of malignancies, renal function or BK virus at 1 year. The primary findings suggest the association of MMF with improved outcomes may not be apparent in patients also receiving tacrolimus.     

Hospitalized psychoses after renal transplantation in the United States: incidence,risk factors,and prognosis

Although it is recommended that renal transplant (RT) candidates routinely undergo screening for mental health-related conditions, national statistics for psychoses after RT have not been reported. This is a historical cohort study of 39,628 renal transplant recipients in the United States Renal Data System between July 1, 1994, and June 30, 1998, and followed until December 31, 1999. Adjusted hazard ratios (AHR) for time to hospitalization for both a primary and secondary discharge diagnosis of psychoses (ICD-9 codes 290.x-299.x) after RT and mortality/graft loss after psychosis were assessed by Cox Regression. In addition, rates of psychosis were compared with 178,986 patients with Medicare as their primary payer who started chronic dialysis from April 1, 1995, to June 29, 1999. The incidence of psychoses was 7.5/1000 person-years (PY) after RT compared with 7.2/1000 PY for all patients on chronic dialysis and 9.6/1000 PY for dialysis patients aged 65 yr or younger. Among RT recipients, graft loss (AHR, 2.97; 95% CI, 2.19 to 4.02), allograft rejection, and cadaveric donation were independently associated with psychosis, which was associated with an increased risk of both death (AHR, 2.09; 95% CI, 1.71 to 2.56; P < 0.001) and graft loss (AHR, 1.79; 95% CI, 1.15 to 2.78; P = 0.01). Graft loss due to noncompliance was significantly more common after psychosis (9.0% versus 3.7% in patients not hospitalized for psychosis; P < 0.001). The incidence of hospitalized psychosis was not substantially higher after RT compared with chronic dialysis patients. Psychoses were independently associated with increased risk of death and graft loss after renal transplantation, possibly mediated through medical non-adherence.     

Infection-related mortality in a large cohort of renal transplant recipients

INTRODUCTION: Infections represent a major cause of morbidity and mortality among renal transplant recipients. Our aim was to analyze the incidence and etiology of infection-related mortality among a large cohort of renal transplant recipients. METHODS: From 1995 to 2004, we collected all causes of mortality among patients receiving a renal transplantation. The date of transplant, the last follow-up/death, type of transplant, age, and cause of death were tabulated into a database. The incidence rate of mortality was calculated in events per 10,000 transplant months. RESULTS: Among the 1218 renal transplants performed in the study period the causes of mortality were: cardiovascular, 65 (38%); infection, 49 (29%); cancer, 21 (12%); other causes, 18 (10.5%); and unknown, 18 (10.5%). Infection-related mortality were: sepsis = 17 (35%), bacterial pneumonia = 9 (18%), abdominal bacterial infection = 2 (4%), invasive viral infection = 12 (24%), and invasive fungal infection = 9 (18%). There were no differences in the global causes of mortality according to the year of transplantation. The incidence rate of infection-related mortality was higher among aged patients and similar to cardiovascular-related mortality. Comparing the periods 1995 to 1999 with 2000 to 2004, bacterial infection-related mortality remained stable (57% vs 57%), while viral infection-related mortality decreased (31% vs 7%) and fungal infection-related mortality increased (11% vs 36%; P = .06). CONCLUSIONS: In the last decade, infection-related mortality among renal transplant recipients has not decreased. Although better control of invasive viral infections has been achieved, bacterial and fungal invasive infections remain important causes of mortality in this population.     

Hospitalized gastrointestinal bleeding and procedures after renal transplantation in the United States

The risk of hospitalized gastrointestinal bleeding (GIB) in renal transplant recipients has not been studied in a national renal transplant population. Therefore, 42,906 renal transplant recipients in the United States Renal Data System (USRDS) from 1 July 1994 - 30 June 1998 were analyzed in an historical cohort study of hospitalizations with a primary discharge diagnosis of GIB (ICD9 Code 578.9x) using Cox regression analysis. The 1997 National Hospital Discharge Survey was used to obtain rates of GIB for the general population. Renal transplant recipients had a cumulative incidence of hospitalizations for GIB of 334 events/100,000 person-years. In 1997, compared to the general population, renal transplant recipients had an age-adjusted rate ratio for GIB of 10.69 at one year of follow-up. The strongest risk factors for GIB in Cox regression analysis were graft loss (adjusted hazard ratio, 4.28 (2.84-6.47) and African American recipients who experienced allograft rejection (AHR, 3.04, 95% CI, 1.45-6.37). GIB was associated with increased all-cause mortality (hazard ratio 1.78, 95% CI, 1.39-2.28). GIB is significantly more common in renal transplant recipients than in the general population, and the strongest risk factors are graft loss and African Americans who experience rejection.     

Mycobacterium Tuberculosis Infection Incidence in Hospitalized Renal Transplant Patients in the United States, 1998–2000

The incidence, risk factors, and prognosis for Mycobacterium tuberculosis (MTB) infection have not been reported in a national population of renal transplant recipients. We performed a retrospective cohort study of 15,870 Medicare patients who received renal transplants from January 1, 1998 to July 31, 2000. Cox regression analysis derived adjusted hazard ratios (AHR) for factors associated with a diagnosis of MTB infection (by Medicare Institutional Claims) and the association of MTB infection with survival. There were 66 renal transplant recipients diagnosed with tuberculosis infection after transplant (2.5 cases per 1000 person years at risk, with some falling off of cases over time). The most common diagnosis was pulmonary TB (41 cases). In Cox regression analysis, only systemic lupus erythematosus (SLE) was independently associated with TB. Mortality after TB was diagnosed was 23% at 1 year, which was significantly higher than in renal transplant recipients without TB (AHR, 4.13, 95% CI, 2.21, 7.71, p < 0.001). Although uncommon, MTB infection is associated with a substantially increased risk of mortality after renal transplantation. High-risk groups, particularly those with SLE prior to transplant, might benefit from intensified screening.     

Hepatitis C, acute humoral rejection, and renal allograft survival

The effect of recipient hepatitis C virus (HCV) infection on renal allograft loss and acute rejection in kidney transplantation remains controversial. We studied 354 renal allograft recipients transplanted during 1996 to 2001 who had HCV antibodies (Ab) measured before transplantation. The primary outcome was death-censored allograft loss and the secondary outcome was acute humoral rejection (AHR). Compared with HCV Ab-negative patients, those with positive HCV Ab had longer time on dialysis before transplantation, higher percentage of panel-reactive antibodies (PRA), were more likely to receive a cadaveric transplant, and were more likely to develop delayed graft function (DGF). In univariate analyses, predictors of renal allograft loss included HCV, cadaveric graft, PRA >20%, HLA mismatch > or =5, retransplantation, DGF, induction therapy, and AHR. When adjusted for PRA >20%, HLA mismatch > or =5, and multiple transplant status, HCV was not a statistically significant predictor of allograft loss. HCV was also associated with AHR but lost significance when adjusted for PRA >20%. HCV Ab-positive patients were more likely to have longer duration of dialysis before transplantation prior to kidney transplants, higher PRA, and to receive cadaveric transplants. These characteristics likely resulted in more DGF and AHR after transplantation. After adjusting for these confounding factors, the association between HCV Ab positivity and renal allograft loss was notably attenuated and no longer statistically significant.     

Hospitalizations for bacterial endocarditis after renal transplantation in the United States.

PURPOSE: The national rate of and risk factors for bacterial endocarditis in renal transplant recipients has not been reported. METHODS: Retrospective registry study of 33,479 renal transplant recipients in the United States Renal Data System (USRDS) between 1 July 1994 and 30 June 1997. Hospitalizations for a primary diagnosis of bacterial endocarditis (ICD-9 codes 421.x) within three years after renal transplant were assessed. RESULTS: Renal transplant recipients had an unadjusted incidence ratio for endocarditis of 7.84 (95% confidence interval 4.72-13.25) in 1996. In multivariate analysis, a history of hospitalization for valvular heart disease (adjusted odds ratio (AOR), 25.81, 95% confidence interval 11.28-59.07), graft loss (AOR, 2.81, 95% CI 1.34-5.09), and increased duration of dialysis prior to transplantation were independently associated with hospitalizations for bacterial endocarditis after transplantation. Hospitalization for endocarditis was associated with increased patient mortality in Cox Regression analysis, hazard ratio 4.79, 95% CI 2.97-6.76. CONCLUSIONS: The overall incidence of bacterial endocarditis was much greater in renal transplant recipients than in the general population, although it is still relatively infrequent. Independent risk factors for bacterial endocarditis in the renal transplant recipients were identified, the most significant of which was valvular heart disease. Endocarditis substantially impacts renal transplant recipient survival.     

Relevance of Toll-like receptor-4 polymorphisms in renal transplantation

BACKGROUND: Polymorphisms in Toll-like receptor-4 (TLR4) have been reported to be associated with a blunted immune response to microbial pathogens, as well as a decreased risk of atherosclerosis in the general population. We assessed the impact of the two TLR4 variants on the risk of severe infection, the incidence of acute rejection, and the occurrence of atherosclerotic complications in renal transplant recipients (RTR). METHODS: TLR-4 polymorphisms were assessed in a cohort of 238 RTR. Post-transplant atherosclerotic events, acute rejection, severe bacterial infection, cytomegalovirus (CMV) disease, and opportunistic infections were evaluated as outcomes. RESULTS: The patients were followed for a mean duration of 95 +/- 29 months after transplant. TLR4 polymorphism was observed in 27 (11.3%) RTR. Subjects with TLR4 polymorphisms were less likely to experience post-transplant atherosclerotic events (RR 0.44; 95% CI 0.21 to 0.93; P= 0.02) and acute rejection (RR 0.41; 95% CI 0.30 to 0.83; P= 0.01), but presented severe bacterial infections (RR 1.33; 95% CI 1.12 to 1.67; P= 0.01) and opportunistic infections (RR 3.03; 95% CI 1.72 to 8.29; P= 0.008) more frequently. TLR4 polymorphism was marginally associated with CMV disease (RR 1.47; 95% CI 0.95 to 2.64; P= 0.08). CONCLUSION: RTR with TLR4 polymorphism present a lower risk of post-transplant atherosclerotic events and acute allograft rejection, but experience severe infectious episodes more frequently. This subset of RTR may benefit from a less potent immunosuppression regimen, along with increased preventive measures against infectious agents.     

Adolescents are more likely to develop posttransplant lymphoproliferative disorder after primary Epstein-Barr virus infection than younger renal transplant recipients

BACKGROUND: Primary Epstein-Barr virus (EBV) infection is the most important risk factor for development of posttransplant lymphoproliferative disorder (PTLD). Pediatric patients are often EBV seronegative pretransplant placing them at high risk. In the immune-competent population, primary herpesvirus infection is associated with higher morbidity with increasing age. METHODS: We performed a retrospective cohort study to describe the outcome of pediatric renal transplant recipients with primary EBV infection. All patients received 3 months of ganciclovir prophylaxis. Real-time quantitative polymerase chain reaction was used to determine the EBV viral load. Primary EBV infection was categorized as PTLD, symptomatic infection, or subclinical infection. RESULTS: There were a total of 46 patients with primary EBV infection: 11 developed PTLD, 12 had symptomatic infection, and 23 had subclinical infection. Adolescents were significantly more likely to develop PTLD than younger transplant recipients (P=0.05, chi-square). Multivariate analysis using logistic regression found that older age was the only significant risk factor for PTLD (odds ratio 1.24, 95% confidence interval 1.04-1.47; P=0.03). Among the 11 cases of PTLD, there were two deaths and two graft failures which all occurred in adolescent recipients (P=0.002). CONCLUSIONS: Among pediatric renal transplant recipients with primary EBV infection, adolescents are at significantly higher risk to develop PTLD and have poorer outcomes compared to younger recipients.     

Multivariate analysis of the effectiveness of using antibody induction therapy according to the degree of HLA mismatches

OBJECTIVE: HLA mismatches have a strong impact on acute rejection and renal allograft survival. The objective of this study was to evaluate the effectiveness of antibody induction according to the degree of HLA mismatches. METHODS: Of 20,429 deceased donor (DD) transplantations and 12,859 living donor (LD) transplantations reported to the United Network for Organ Sharing (UNOS) between 1999 and 2001, 51% of DD and 45% of LD transplant recipients received induction therapy. Propensity scores (PS) were calculated to indicate independent factors associated with the use of induction. Levels of HLA match examined for DD transplant recipients were 0 ABDR (n = 3239), 0 DR (n = 4210), and DR mismatched transplants (n = 12,980), and 0 (n = 1133), 1 (n = 3836), and 2 (n = 7890) haplotype mismatches for LD transplant recipients. Outcome parameters were reported as hazard ratios (HR) for graft loss and odds ratios (OR) for first-year acute rejection. RESULTS: Recipients with HLA mismatches were more likely to receive induction antibody for DR mismatch in DDs (PS = 1.11, 95% confidence interval [CI] 1.04-1.19) and for haplotype mismatch in LDs (PS = 1.36, 95% CI 1.22-1.52). Induction reduced the likelihood of acute rejection for DD transplant recipients regardless of the level of HLA mismatch (OR = 0.70; 95% CI 0.57-0.85 in 0 ABDR MM; OR = 0.76, 95% CI 0.64-0.89 in 0 DR MM; and OR = 0.69, 95% CI 0.62-0.77 in DR MM), and for 2 haplotype mismatched LD transplant recipients (OR = 0.82, 95% CI 0.70-0.96); in other LD transplant recipients, reductions in acute rejection rates were observed but not statistically significant. Induction reduced the risk of graft loss for DR mismatched DD transplant recipients by about 12% (HR = 0.88; 95% CI 0.80-0.97). CONCLUSIONS: Antibody induction resulted in a significant reduction of acute rejection and graft loss for patients with HLA mismatch.     

Is mycophenolate mofetil less safe than azathioprine in elderly renal transplant recipients?

BACKGROUND: Mycophenolate mofetil (MMF) is a potent immunosuppressive agent that has been shown to be superior to azathioprine in preventing early acute rejection in the general renal transplant population. However, it is uncertain whether these benefits also apply to older renal transplant recipients, who are known to be more susceptible to infectious complications and have considerably lower rates of rejection and immunological graft loss. METHODS: A retrospective analysis was undertaken of all elderly (> or =55 years old) renal transplant recipients who underwent renal transplantation at the Princess Alexandra Hospital (1994-2000) and received either MMF (n=60) or azathioprine (n=55) in combination with prednisolone and cyclosporin. Data were analyzed on an intention-to-treat basis using a multivariate Cox proportional hazards model. RESULTS: The azathioprine- and MMF-treated groups were well matched at baseline with respect to demographic characteristics, end-stage renal failure causes and transplant characteristics. Compared with the MMF cohort, azathioprine-treated patients experienced a shorter time to first rejection [hazard ratio (HR) 4.47, 95% CI 1.53-13.1, P<0.01]. However, azathioprine-treated patients were also less likely to develop opportunistic infections (HR 0.11, 95% CI 0.03-0.41, P=0.001). No differences were observed between the two groups with respect to hospitalization rates, intensive care admissions, hematological complications, or posttransplant malignancies. Actuarial 2-year survival rates for the azathioprine- and MMF-treated patients were 100 and 87%, respectively (P<0.001). The principal cause of death in the MMF cohort was infection. Using a multivariate Cox regression analysis of patient survival, an adjusted hazard ratio of 0.01 (95% CI 0.001-0.08, P=0.001) was calculated in favor of azathioprine. Overall graft survival also tended to be better in patients receiving azathioprine (HR 0.27, 95% CI 0.06-1.33, P=0.11), CONCLUSIONS: In elderly renal transplant recipients, the combination of MMF, cyclosporin, and prednisolone appears to result in a worse outcome compared with the less potent combination of azathioprine, cyclosporin, and prednisolone. Future prospective studies need to specifically evaluate the risk/benefit ratios of newer, more potent immunosuppressive protocols, such as MMF-based regimens, in this important and sizeable patient subgroup.     

Skin infections in renal transplant recipients and the relation with solar ultraviolet radiation

BACKGROUND: Ultraviolet radiation (UVR) is an important risk factor for skin cancer in transplant recipients. In view of the potential suppressive effect of UVR on host resistance it was examined whether exposure to UVR was also associated with the occurrence of various skin infections. METHODS: In a cohort of renal transplant recipients (n = 137), lifetime exposure was assessed by means of a retrospective questionnaire on cumulative sunlight exposure. Diagnosed skin infections since renal transplantation were extracted from the patient's medical charts. Season of diagnosis was regarded as indicative of short-term exposure. RESULTS: In comparison with winter a high rate of herpes simplex infections was found in spring [rate ratio (RR) = 4.09, 95% confidence interval (CI) 1.2-14.5], and high rates of herpes zoster infections (RR = 1.6, 95% CI: 0.8-3.5) and fungal/yeast infections in summer (RR = 2.1, 95% CI: 1.3-3.4). A higher lifetime exposure (RR = 2.31, 95% CI: 1.04-5.1) and a greater cumulative number of reported sunburns (RR = 2.3, 95% CI: 1.1-5.1) were independently associated with a higher risk of bacterial infections. CONCLUSIONS: The seasonal association with the occurrence of clinical herpes infections indicates an effect of short-term UVR. Our data suggest that the number of sunburn episodes in the past is also relevant for the susceptibility to certain skin infections.     

Increased septic complications with three-drug sequential immunosuppression for cadaver renal transplants

In 152 renal transplant recipients, the results of immunosuppression with three-drug sequential (Minnesota antilymphocyte globulin, prednisone, azathioprine, and cyclosporine) immunosuppression (n = 107) were compared with those of a two-drug sequential protocol (Minnesota antilymphocyte globulin, prednisone, and cyclosporine) that excluded azathioprine (n = 45). The study groups were comparable by age, sex, etiology of renal failure, incidence of diabetes, and degree of HLA matching. Patient survival at 1 year was not significantly different in the two groups (two drug, 93% versus three drug, 86%; p = 0.19). One-year graft survival was superior in the two-drug group (two drug, 93% versus three drug, 75%; p = 0.02). Analysis of primary transplants only (n = 116) yielded the same results. During the first year, the serum creatinine level remained stable in both groups. As expected, the three-drug therapy group had significantly more bacterial and viral infections. For low-risk primary cadaveric renal transplants, two-drug sequential immunosuppression is superior.     

Humoral response to natural influenza infection in solid organ transplant recipients

The humoral immune response of transplant recipients to influenza vaccination has been studied in detail. In contrast, the hemagglutinin inhibiting (HI) antibody response evoked by natural influenza infection and its impact on viral kinetics is unknown. In this prospective, multicenter, cohort study of natural influenza infection in transplant recipients, we measured HI antibody titers at presentation and 4 weeks later. Serial nasopharyngeal viral loads were determined using a quantitative influenza A polymerase chain reaction (PCR). We analyzed 196 transplant recipients with influenza infection. In the cohort of organ transplant patients with influenza A (n = 116), seropositivity rates for strain‐specific antibodies were 44.0% (95% confidence interval [CI] 31.5‐53.2%) at diagnosis and 64.7% (95% CI 55.4‐72.9%) 4 weeks postinfection. Seroconversion was observed in 32.8% (95% CI 24.7‐41.9%) of the cases. Lung transplant recipients were more likely to seroconvert (P = .002) and vaccine recipients were less likely to seroconvert (P = .024). A subset of patients (n = 30) who were unresponsive to prior vaccination were also unresponsive to natural infection. There was no correlation between viral kinetics and antibody response. This study provides novel data on the seroresponse to influenza infection in transplant patients and its relationship to a number of parameters including a prior vaccination status, virologic measures, and clinical variables.     

Prevalence and risk factors for early postoperative infection after liver transplantation

OBJECTIVES: To analyze factors related to the development of infection soon after a liver transplant. PATIENTS AND METHOD: Retrospective study of 1000 liver transplants in adults between 1991 and 2004. Pre-, intra- and postoperative variables of recipients were analyzed in 2 groups according to whether infection did or did not develop. RESULTS: Infection developed in 151 patients. Bacterial infections were the most common type. Significant risk factors for infection in the multivariate analysis were sex (odds ratio [OR], 0.54; 95% confidence interval [CI], 0.33-0.90); Child-Pugh stage (OR, 1.89; 95% CI, 1.29-2,77); hepatitis C virus cirrhosis (OR, 0.58; 95% CI, 0.34-0.99); post-reperfusion syndrome (OR, 1.82; 95% CI, 1.03-3.21); vena cava preservation technique (OR, 0.43; 95% CI, 0.22-0.84); history of diabetes mellitus (OR, 2.38; 95% CI, 1.34-4.22); respiratory distress syndrome (OR, 6.60; 95% CI, 1.16-37.45); pulmonary edema (OR, 2.36; 95% CI, 1.44-3.86); renal dysfunction (OR, 3.25; 95% CI, 1.89-5.60); acute renal insufficiency (OR, 20.24; 95% CI, 9.88-41.46); neurological alterations (OR, 3.36; 95% CI, 1.94-5.821); postoperative bleeding (OR, 2.80; 95% CI, 1.32-5.97); graft dysfunction (OR, 2.07; 95% CI, 1.21-3.53); primary graft failure (OR, 0.07; 95% CI, 0.01-0.33). CONCLUSION: Infection is a serious complication that continues to be difficult to control. Certain risk factors can be improved with careful management (kidney failure, pulmonary edema) or appropriate donor-recipient matching (initial dysfunction). Others, however, are inherent to the procedure (post-reperfusion syndrome, sex) or to immunosuppression, which acts as a true mediator of infection with regard to both its appearance and its clinical manifestation.     

The relative risk of overall graft loss and acute rejection among African American renal transplant recipients is attenuated with advancing age

Schold JD, Srinivas TR, Braun WE, Shoskes DA, Nurko S, Poggio ED. The relative risk of overall graft loss and acute rejection among African American renal transplant recipients is attenuated with advancing age.
Clin Transplant 2011: 25: 721–730. © 2010 John Wiley & Sons A/S. Abstract: Background: Graft loss rates are elevated among African American (AA) kidney transplant recipients. This may be attributable to immunological responses, socioeconomic disparities, comorbid conditions and access to care, but it is unclear whether risks are uniform in the AA population. Methods: We utilized multivariable models with the national SRTR database for adult recipients transplanted from 2000 to 2009 (n = 112 120) to investigate whether risks of graft loss, death and acute rejection between AAs and Caucasians vary with age. Results: Relative to Caucasians, AA recipients had significantly higher risk of overall graft loss among patients aged 18–49 (AHR = 1.37, 95% CI 1.30–1.43) but comparable risk among patients aged >65 (AHR = 1.04, 95% CI 0.96–1.13). Among recipients aged 18–34, AAs had higher risk of acute rejection (AOR = 1.33, 95% CI 1.12–1.57) but similar likelihood among recipients aged >65 (AOR = 0.94, 95% CI 0.75–1.17). Differences between race groups, as well as the relatively higher risks among younger AAs, were most pronounced following one yr post‐transplantation and diminished with presence of other risk factors. Conclusions: Elevated risks of overall graft loss and acute rejection are present among younger but not older AA kidney transplant recipients. These findings may have important implications for treatment decisions, follow‐up protocols and designation of “high‐risk” patients.