Biomedical subjects

David W Gjertson

Publications and source records attributed to David W Gjertson.

At least 19 recordsLinked to original sources

PubMed2007

Long-term comparative outcomes between 2 common ureteroneocystostomy techniques for renal transplantation.

PURPOSE: We compared the incidence of ureteral complications between the classic (Lich-Gregoir) technique and the recently popularized single stitch (Shanfield) technique in renal transplantation. MATERIALS AND METHODS: The charts of 721 consecutive transplant recipients from May 1999 to July 2002 were retrospectively reviewed. Ureteral and nonureteral complications were reviewed at 3 to 5-year followup. RESULTS: Of the 721 recipients evaluated 713 were included in the study. There were 360 recipients in the Lich-Gregoir group and 353 in the Shanfield group. A significantly higher rate of ureteral complications occurred in the Shanfield group compared to the Lich-Gregoir group (15.6% vs 3.9%, p <0.0001). The Shanfield group consisted of 20 patients with ureteral leakage, 21 with hematuria, 11 with strictures and 3 who had ureteral stones. The Lich-Gregoir group had 8 patients with ureteral leakage, 5 with hematuria and 1 with a stricture. In comparison, urinary tract infections, delayed graft function and rejection rates were not significantly different between the 2 groups (p = 0.76, 0.12 and 0.19, respectively). CONCLUSIONS: In contrast to other reports, the Shanfield group had significantly more ureteral complications. In particular the Shanfield technique may predispose patients to higher rates of hematuria and stone formation. Based on this large series and published meta-analyses we believe that the stented Lich-Gregoir anastomosis is the superior ureteroneocystostomy technique in renal transplantation.

Adult↗

PubMed2006

CD20+ lymphocytes in renal allografts are associated with poor graft survival in pediatric patients.

BACKGROUND: The presence of CD20+ lymphocyte renal allograft infiltrates has been associated with steroid-resistant rejection and poor graft survival. We quantified the number of CD20+ lymphocytes in renal allograft biopsies and correlated the results with graft survival. We also determined the relationships between CD20+ lymphocytes and acute cellular rejection versus antibody-mediated rejection. METHODS: We examined 45 biopsy samples from 31 pediatric patients biopsied for suspicion of rejection from November 2001 to November 2004. Immunohistochemical staining for CD20 and C4d was performed on all biopsies; CD20+ cell density per high-power field (hpf) was determined for each core. Patient graft status was followed postbiopsy and documented for graft survival or failure using the cutoff date of December 31, 2005. RESULTS: Patients with 2-10 and 11-100 CD20+ cells/hpf had worse graft survival in Kaplan-Meier analysis with a hazard ratio 4.56 (CI 1.07-19.35) two years postbiopsy compared to those with 0-1 cells/hpf (P = 0.02). The presence of CD20+ lymphocytes was significantly associated with acute cellular rejection (P = 0.0001) and not associated with antibody-mediated rejection (P = 0.16). Receiver-operating curve analysis confirmed > or =3 cells/hpf correlating with acute cellular rejection, yielding sensitivity 90% and specificity 76%. CONCLUSIONS: This study shows a significant 4.5-fold risk of graft failure at two years postbiopsy with presence of > or =2 CD20+ cells/hpf. Moreover, > or =3 CD20+ lymphocytes were highly associated with acute cellular rejection. They may be functioning as professional antigen-presenting cells in the graft. In steroid-refractory cellular rejections, therapies that target B cells may prolong graft survival.

Adolescent↗

PubMed2006

Receptor-ligand analyses define minimal killer cell Ig-like receptor (KIR) in humans.

Interactions between inhibitory killer cell immunoglobulin-like receptors (iKIR) and human leukocyte antigen (HLA) class I molecules regulate natural killer (NK) cell responses to eliminate infected and transformed cells while maintaining tolerance to healthy cells. Unlinked polymorphic gene families encode KIR receptors and HLA class I ligands and their independent segregation results in a variable number and type of iKIR + HLA pairs inherited in individuals. The diversity in the co-inheritance of iKIR + HLA pairs and activating KIR (aKIR) genes in 759 unrelated individuals from four ethnic populations was analyzed. Every individual studied inherited a minimum of one iKIR + HLA pair; suggesting that major histocompatibility complex class I-dependent inhibitory KIR signaling is essential for human NK cell function. In contrast, 13.4% of the study group lacked all aKIR genes. Twenty percent of the study group carried only one of the four iKIR + HLA pairs. Interestingly, 3% of the study group carrying only KIR2DL3 + HLA-C1 as an iKIR + HLA pair lacked aKIR genes. These data suggest that a single iKIR can constitute the minimal KIR repertoire for human NK cells. Genotypes carrying an equal number of iKIR + HLA pairs and aKIR genes represented 20% of the study group. The remaining individuals had either a dominant inhibitory KIR genotype (iKIR + HLA > aKIR) or a dominant activating KIR genotype (iKIR + HLA < aKIR). Genotypes encoding these imbalanced inhibitory and activating interactions may contribute to susceptibility or resistance to human diseases.

Epitope Mapping↗

PubMed2006

Small airways response to naturalistic cat allergen exposure in subjects with asthma.

BACKGROUND: It is currently unclear whether the small airways (diameter <2 microm) contribute significantly to late asthmatic reactions to inhaled allergen. OBJECTIVES: We sought to determine whether naturalistic exposure to cat allergen induced late responses in the small airways as measured by pulmonary function testing and high-resolution computed tomography (HRCT) of the chest performed at end-expiration. METHODS: In a group of 10 subjects with cat-induced asthma, physiologic studies (spirometry and lung volumes, including closing volume) and HRCT were performed before and 6 and 23 hours after a cat room challenge that caused a 20% or greater acute fall in FEV(1). RESULTS: There was no significant decline in FEV(1) at 6 or 23 hours after cat exposure. Forced expiratory flow at 25% to 75% of forced vital capacity was significantly decreased at 6 hours after the challenge and returned to normal by 23 hours. HRCT image analysis as well as closing volume demonstrated increased air trapping from baseline at both 6 and 23 hours after the challenge. In addition, image analysis demonstrated a significant increase in small airways hyperresponsiveness to methacholine at 23 hours after the challenge. No significant mean changes were noted in lung volumes at either 6 or 23 hours or in PC(20) FEV(1) at 23 hours postchallenge. CONCLUSION: These findings demonstrate that naturalistic exposure to cat allergen results in significant small airways obstruction and hyperresponsiveness persisting for at least 23 hours, at which time these changes cannot be detected by conventional physiologic measures. CLINICAL IMPLICATIONS: Physiologically silent distal lung inflammation persists after an antigenic challenge.

Adult↗

PubMed2006

Noninvasive diagnosis of cellular and antibody-mediated rejection by perforin and granzyme B in renal allografts.

A major milestone in transplantation would be the use of biomarkers to monitor rejection. We examined the association between perforin and granzyme-B gene expression detected in the peripheral blood of renal allograft recipients with cellular and antibody-mediated rejection. Furthermore, we judged the appropriateness of assigning negative rejection statuses to persons without a biopsy whose grafts were functioning well clinically. Of the 46 patients who completed the study, recipients with cellular rejection had higher perforin and granzyme-B levels compared with nonrejectors (p = 0.006). Interestingly, recipients with antibody-mediated rejection also had higher perforin and granzyme-B levels compared with nonrejectors (p = 0.04). Patients with high levels of granzyme B had a probability of rejecting that was 26.7 times greater than those patients with low levels of granzyme B. Perforin and granzyme B had sensitivities of 50% and specificities of 95% in predicting rejection (cutoff value = 140). Assigning negative rejection statuses to recipients without a biopsy whose grafts were functioning well did not have a major effect on the direction or significance of covariate values. This study suggests that perforin and granzyme-B gene expressions in peripheral blood are accurate in detecting both cellular and antibody-mediated rejection.

Adult↗

PubMed2006

HIV-positive renal recipients can achieve survival rates similar to those of HIV-negative patients.

BACKGROUND: Although patients positive for HIV were once thought to be unsuitable candidates for kidney transplantation, their increasing numbers with end-stage renal disease (ESRD) and the introduction of highly active antiretroviral therapy has indicated that they should no longer be excluded for transplantation. To counteract suggestions that human immunodeficiency virus (HIV) patients received suboptimal kidneys, we provide studies of kidneys transplanted from the same donor into patients with and without HIV. METHODS: United Network for Organ Sharing kidney transplant data between 1997 and 2004 were analyzed. Graft and patient survival of 38 HIV patients who had received a renal transplant were compared with the survival of 38 recipients who had received a graft from the same donor. RESULTS: The 38 HIV-positive recipients were younger (49.0 vs. 52.3 years, P=0.14) and had lower peak panel-reactive antibodies (PRA; 5.1% vs. 15.6%, P=0.07) when compared with their bilateral donor to HIV-negative recipients. Sirolimus was used more frequently in HIV patients than in non-HIV patients (36.8% vs. 23.7%, P=0.09). The serum creatinine at 1, 3, and 5 years posttransplantation were higher in HIV patients when compared to non-HIV patients. Although not statistically significant, graft survival was higher among HIV-positive patients compared with their negative controls (76.1% vs. 65.1% at 5 years, P=0.21), as was patient survival (91.3% vs. 87.3% at 5 years, P=0.72). More grafts failed due to death with a functioning graft than rejection in HIV-positive patients. CONCLUSION: This study supports the position that there is no longer an ethical question surrounding the use of kidneys for HIV-positive patients.

Female↗

PubMed2006

A novel flow assay for the detection of cytokine secreting alloreactive T cells: application to immune monitoring.

The direct and indirect allorecognition pathways play an important role in graft rejection. We hypothesized that the presence of alloreactive memory T cells in the recipient's circulation increases the risk of rejection after transplantation. The objective of this study was to develop a noninvasive, immune monitoring tool that simultaneously measures donor-specific responses via both the direct and indirect recognition pathways. Our laboratory developed a whole blood flow cytometric cytokine secretion assay to identify interferon (IFN)-gamma secreting memory T cells in whole blood of renal transplant patients. The assay readily detected IFN-gamma producing CD3+ T cells in response to recall antigens tetanus toxoid, purified protein derivative, and alloantigens in whole blood from healthy controls. Analysis of sequential posttransplant blood samples from 19 renal allograft recipients showed that alloimmune responses were higher in transplant recipients who had undergone acute rejection than in those without acute rejection episodes. In addition, patients showing increased creatinine levels 3 months after transplantation were more likely to exhibit alloimmune responses than recipients with stable graft function. The flow cytokine secretion assay provides a reliable and simple method for identification of patients at risk of acute rejection and early graft dysfunction.

Adult↗

PubMed2005

Living-unrelated donors yield higher graft survival rates than parental donors.

BACKGROUND: Living-unrelated donors (LURD) have been shown to yield kidney graft survival rates equivalent to that of related donors. Here, we show that in three diseases, LURDs supply grafts that survive at a higher rate than parental or offspring donors. METHODS: We analyzed 111,643 first adult kidney transplants from the United Network for Organ Sharing database performed between 1991 and 2003 by Kaplan-Meier curves, log-rank tests, and Cox proportional hazard tests. RESULTS: Five-year kidney graft survival rates in patients receiving grafts from LURD, parental, and offspring donors were 75.4%, 74.3%, and 75.7% among patients with typical original diseases excluding three diseases. In focal glomerulosclerosis (FGS), the corresponding results were 87.4%, 70.1%, and 81.6%. In polycystic kidney disease (PC) rates were 86.4%, 78.6%, and 85.3%, and in diabetes mellitus (type 1 DM) rates were 75.9%, 69.8%, and 70.5%. Parental donors yielded significantly lower graft survival rates than LURDs in all three diseases. Although statistically significant differences were lost in the Cox tests, functional graft survival showed significantly lower graft survival rates from parental donors compared with LURDs, suggesting that donor age was a significant factor. CONCLUSIONS: If living donors are considered for kidney transplantation into patients with FGS, PC, or type 1 DM, grafts from LURD are preferred over parental and offspring donors. Although genetic susceptibility of parental and offspring donor grafts may be a factor, the simple donor age factor probably results in lower survival of parental donor grafts. Lower survival of offspring donor grafts may suggest genetic susceptibility because such donors were, in general, younger than in LURD grafts.

Cadaver↗

PubMed2005

Development of posttransplant antidonor HLA antibodies is associated with acute humoral rejection and early graft dysfunction.

BACKGROUND: The goal of this study was to determine whether the production of posttransplant antibodies directed against donor HLA mismatches (donor specific antibody; DSA) is associated with renal allograft rejection and early graft dysfunction. METHODS: Forty-nine adult renal allograft recipients with increased risk of rejection were enrolled during the period of October 2001 through May 2003 and were prospectively monitored for the development of anti-HLA antibodies. RESULTS: Of 49 patients, eight (16.3 %) patients were diagnosed with acute humoral rejection (AHR) and 11/49 (22.4%) patients were diagnosed with acute cellular rejection (ACR). A strong association between pretransplant HLA sensitization and AHR was found (P=0.005). Of the eight patients diagnosed with AHR, the majority developed DSA before or concomitant with episodes of rejection (P<0.001). Only 3 of 41 patients (7.3%) without AHR developed DSA. The pathogenic role of alloantibodies was further substantiated by analyzing their association with graft function as measured by serum creatinine levels. The average serum creatinine after the third month posttransplantation in DSA producers was 2.24+/-1.01 mg/dL, while in non-DSA patients the average serum creatinine was 1.41+/-0.37 mg/dL (P<0.01). CONCLUSION: This study reveals a strong association between the production of DSA, AHR, and early graft dysfunction. Our findings indicate that prospective monitoring for anti-HLA antibodies following transplantation is a useful test for the diagnosis and classification of AHR for identifying patients at risk of early graft dysfunction.

Acute Disease↗

PubMed2005

Computer-aided lung nodule detection in CT: results of large-scale observer test.

RATIONALE AND OBJECTIVES: The objective is to study the incremental effects of using a computer-aided lung nodule detection (CAD) system on the performance of a large pool of observers. MATERIALS AND METHODS: A set of eight thin-section computed tomographic data sets with limited longitudinal coverage, containing a total of 22 lung nodules, was analyzed by using the automated nodule detection system. When applied to all eight cases, the CAD system alone achieved a detection rate of 86.4%, with 2.64 false-positive results per case. This study included 202 observers at a national radiology meeting: 39 thoracic radiologists, 95 non-thoracic radiologists, and 68 non-radiologists. Each participant read from one to eight cases in random order, first without and then with CAD system output available. Observer performance in nodule detection was measured before and after CAD was made available. Differences in performance of groups of observers before and after CAD were tabulated by mean, median, and SD in detection rate and number of false-positive results and tested by using nonparametric methods. RESULTS: In an analysis involving only the first randomly selected case read by all 202 participants, there were statistically significant increases in nodule detection rates and numbers of false-positive results for all types of observers. There was a significant difference in detection rates between radiologists and non-radiologists before CAD, but after CAD, there was no significant difference in detection rates between these observer types. In a second analysis involving 13 participants who read all eight cases, mean detection rates were 64.0% before CAD and 81.9% after CAD. Mean numbers of false-positive results were 0.144 per case before CAD and 0.173 after CAD. CONCLUSION: In a large observer study, use of a CAD system for nodule detection resulted in an incremental increase in detection rate, but also led to an increase in number of false-positive results. Also, CAD appears to be an equalizer of detection rates between observers of different levels of experience.

Clinical Competence↗

PubMed2005

Association of morbid obesity and weight change over time with cardiovascular survival in hemodialysis population.

BACKGROUND: In maintenance hemodialysis (MHD) outpatients, a reverse epidemiology is described, ie, baseline obesity appears paradoxically associated with improved survival. However, the association between changes in weight over time and prospective mortality is not known. METHODS: Using time-dependent Cox models and adjusting for changes in laboratory values over time, the relation of quarterly-varying 3-month averaged body mass index (BMI) to all-cause and cardiovascular mortality was examined in a 2-year cohort of 54,535 MHD patients from virtually all DaVita dialysis clinics in the United States. RESULTS: Patients, aged 61.7 +/- 15.5 (SD) years, included 54% men and 45% with diabetes. Time-dependent unadjusted and multivariate-adjusted models, based on quarterly-averaged BMI controlled for case-mix and available time-varying laboratory surrogates of nutritional status, were calculated in 11 categories of BMI. Obesity, including morbid obesity, was associated with better survival and reduced cardiovascular death, even after accounting for changes in BMI and laboratory values over time. Survival advantages of obesity were maintained for dichotomized BMI cutoff values of 25, 30, and 35 kg/m2 across almost all strata of age, race, sex, dialysis dose, protein intake, and serum albumin level. Examining the regression slope of change in weight over time, progressively worsening weight loss was associated with poor survival, whereas weight gain showed a tendency toward decreased cardiovascular death. CONCLUSION: Weight gain and both baseline and time-varying obesity may be associated with reduced cardiovascular mortality in MHD patients independent of laboratory surrogates of nutritional status and their changes over time. Morbidly obese patients have the lowest mortality. Clinical trials need to verify these observational findings.

Adult↗

PubMed2005

The specific power of parentage exclusion in a child's blood relatives.

BACKGROUND: The impersonation of parent and child by two other blood relatives is an important problem in parentage analysis involving potential immigrants. STUDY DESIGN AND METHODS: A statistic (AR) is proposed, based on the specific power of exclusion of paternity, which describes the ability of a child's test results to demonstrate evidence of nonparentage under the hypothesis that an ostensible parent is actually an older sibling. A case illustrates the value of A(R): a woman and her two alleged children were typed at 3 variable number of tandem repeat (VNTR) loci after 18 short tandem repeat (STR) loci initially showed strong evidence of the woman's maternity of one child and her exclusion from parentage of the second. AR and 1 - AR were calculated from the STR types of the first child. RESULTS: The woman was excluded from maternity of both children with the additional VNTR tests. Given the 18 STR test findings of the first child, the probability was 12 percent that there would be no inconsistencies with parentage in a sibling pretending to be a parent. CONCLUSION: The value 1 - AR, siblings not excluded from parentage, explains how a seemingly large number of examined loci can fail to reveal even one genetic inconsistency if two siblings have posed as parent and child. Approximately 25 STR loci appear necessary to achieve 95 percent confidence of detecting at least one genetic inconsistency indicative of nonparentage.

Adult↗

PubMed2004

Polymorphism of transporter associated with antigen presentation 1 as a potential determinant for severity of disease in recurrent respiratory papillomatosis caused by human papillomavirus types 6 and 11.

Recurrent respiratory papillomatosis (RRP) is a rare disease caused by human papillomaviruses (HPVs). It is characterized by multiple recurrences of benign neoplasms and has a variable clinical course, ranging from infrequent recurrence to acute airway obstruction. One way in which HPV subverts the immune system in RRP is by interfering with TAP1 (transporter associated with antigen presentation 1). We examined whether a known TAP1 polymorphism in the ATPase domain altered the severity of disease in patients with RRP. The presence of this polymorphism was significantly correlated with severity of disease (P=.015). Because of the proximity of the TAP1 gene to human leukocyte antigen (HLA) class II genes on chromosome 6, we postulated that a linkage disequilibrium may exist. Of the patients with polymorphic TAP1, 36% were positive for HLA-DRB1*0102 (P=.021; P=.147 with Bonferroni's correction). However, this association appeared to mitigate the severity of disease (P=.04). Therefore, severity of disease in a patient with RRP might be determined by sequencing TAP1, in conjunction with HLA class II genes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2004

Human leukocyte antigen A29 subtypes associated with birdshot retinochoroidopathy.

PURPOSE: To determine whether birdshot retinochoroidopathy is associated with subtypes of the human leukocyte antigen (HLA)-A29 other than HLA-A*2902. DESIGN: Experimental study. METHODS: High-resolution DNA typing of HLA-A29 subtypes was performed on blood from 20 subjects with birdshot retinochoroidopathy using polymerase chain reaction-based typing methods. Results were compared with published controls. RESULTS: Four of 20 subjects (20%) had the HLA-A*2901 allele; two were homozygous for HLA-A*29, and both had the HLA-A*2901 and HLA-A*2902 alleles. Among 18 subjects with only one HLA-A*29 allele, the HLA-A*2902 allele was found in 16 (89%) and the HLA-A*2901 allele was found in two (11%). No subject was found to have HLA-A*2903, HLA-A*2904, HLA-A*2905, or HLA-A*2906. CONCLUSIONS: Both HLA-A*2901 and HLA-A*2902 are associated with birdshot retinochoroidopathy. Our data do not support the previous suggestion that the HLA-A29.1 serotype may be protective against development of birdshot retinochoroidopathy. Additional studies will be required to determine whether the other, less common subtypes are associated with the disease. HLA-A29 subtype testing is not required for the clinical evaluation of HLA-A29-positive patients with birdshot retinochoroidopathy.

Chorioretinitis↗

PubMed2004

HLA alleles, IFN-gamma responses to HPV-11 E6, and disease severity in patients with recurrent respiratory papillomatosis.

Recurrent respiratory papillomatosis (RRP) remains an immunologic enigma. Human papillomavirus (HPV) types 6 and 11 are the predominant HPV viruses that cause papilloma development. However, it is unclear why only a very small fraction of HPV-exposed individuals develop RRP. We performed high-resolution HLA class I and II genotyping on 70 randomly selected patients (56 Caucasians and 14 African-Americans) with RRP. We report, for the first time, an increased frequency of HLA-DRB1*0102 in Caucasian patients with RRP, suggesting that this allele predisposes individuals to RRP. Additionally, HLA-DRB1*0301, DQB1*0201, and DQB1*0202 alleles were selectively enriched in Caucasians with severe disease, suggesting that these alleles may regulate disease severity. In contrast, HLA-DQB1*0602 was more frequent in controls than in Caucasians with severe disease, suggesting a severity-sparing effect of this allele. Furthermore, both DQB1*0201 and DQB1*0202 were enriched, whereas DQB1*0602 was absent, in African-Americans. Interestingly, HLA-DRB1*0301 and DQB1*0201 correlated with reduced interferon-gamma expression in patients with RRP. Larger studies are needed to identify other class II major histocompatibility complex alleles that may influence disease predisposition, disease severity, or both, especially in African-American patients, to ultimately illuminate the regulatory effects of these alleles in the predisposition and severity of RRP.

Black or African American↗

PubMed2004

Impact of portal venous pancreas graft drainage on kidney graft outcome in simultaneous pancreas-kidney recipients reported to UNOS.

Clinical data on the potential immunologic impact of portal (PD) vs. systemic (SD) venous pancreas graft drainage on outcome remains controversial. We reviewed the UNOS database to study the effect of PD vs. SD on the incidence of kidney graft rejection and survival in first cadaveric simultaneous pancreas-kidney (SPK) recipients transplanted 1994-2001. We studied three groups: all SPK (n=6629, 13% PD) (group I), SPK on tacrolimus (n=3563, 17% PD) (group II), and SPK on tacrolimus performed at centers with significant PD experience (n=948, 46% PD) (group III). The cumulative kidney graft rejection incidence for PD vs. SD was only significantly different in group I (for PD vs. SD, respectively: at 6 months, 31% vs. 36% [p=0.015]; at 1 year, 37% vs. 43% [p=0.006]). Kidney graft survival was similar in all groups for PD vs. SD. Multivariate analysis of group III showed only transplantation during the earlier era (1994-96), but not SD, to be an independent risk factor for kidney graft rejection. Portal venous pancreas graft drainage does not affect kidney graft rejection and survival in SPK recipients on tacrolimus. Our data suggests that the efficacy of current immunosuppressive protocols and increasing center experience are clinically much more relevant than any potential immunologic advantage of portal venous drainage in SPK recipients.

Adult↗

PubMed2004

Emphysema: effect of reconstruction algorithm on CT imaging measures.

In the current study, the effects of reconstruction algorithms on quantitative measures derived from computed tomographic (CT) lung images were assessed in patients with emphysema. CT image data sets were reconstructed with a standard algorithm and alternative algorithm(s) for 42 subjects. Algorithms were grouped as overenhancing, sharp, standard, or smooth. Density mask and volume measurements from the alternative algorithm data sets were compared with standard algorithm data sets. The overenhancing category yielded an average shift of 9.4% (ie, a shift in average score from 35.5% to 44.9%); the sharp category, a shift of 2.4%; and the smooth category, a shift of -1.0%. Differences in total lung volume measurements were less than 1%. In conclusion, the CT reconstruction algorithm may strongly affect density mask results, especially for certain reconstruction algorithms.

Aged↗

PubMed2004

Explainable variation in renal transplant outcomes: a comparison of standard and expanded criteria donors.

In 2002, OPTN/UNOS altered kidney allocation rules to allow patients to be listed separately to receive kidneys from expanded criteria donors (ECD). Our aim was to quantify the short- and long-term impacts of 21 prognostic factors on recipients of ECD as well as recipients of living (LD) and deceased standard criteria (SCD) donors. A factor's impact depends on both the risk and diversity of its effects. Using OPTN/UNOS Registry data from 1996-2003, we have analyzed kidney-only, adult-recipient grafts for factor effects among 35,878 LD, 47,941 SCD and 10,399 ECD transplants. During an early risk period, all 94,218 recipients were followed through one year, and, in the late risk period, 85,270 recipients whose grafts survived beyond one year were followed for 5 years post-transplant. Impact was measured by determining a factor's percentage of assignable variation in one- and 5-year graft failure rates. Scores for 21 factors were estimated via generalized logistic models, which contained a random component for transplant center. The assignable variation associated with a given factor was computed as the factor score variance multiplied by the square of the corresponding regression coefficient. Impacts were heterogeneous with regard to posttransplant period and donor type. The top 5 factors influencing one-year graft survival rates were as follows: * For LD grafts - pretransplant dialysis time (14% of the variation in short-term outcomes), recipient age (13%), body mass (12%), PRA (10%) and induction therapy (10%). * For SCD grafts - donor age (24%), recipient age (12%), pretransplant dialysis time (12%), HLA-DR matching (6%) and pretransplant medical condition (6%). * For ECD grafts - donor age (18%), pre-transplant dialysis time (10%), recipient age (10%), pretransplant medical condition (10%) and recipient body mass (6%). Ranking long-term outcomes demonstrated the following top 5 influential factors: * For LD grafts - donor age (28% of the variation in long-term outcomes), recipient race (15%), age (15%), transplant year (13%) and recipient sex (11%). * For SCD grafts - donor age (35%), recipient race (23%), transplant year(15%), recipient sex (8%)and age (5%). * For ECD grafts - donor age (33%), recipient sex (20%), race (15%), transplant year (8%) and recipient's original disease (5%). Donor age was the dominant factor governing the survival rates among deceased donor kidney transplants. Advancing donor age was still the major risk factor for SCD transplant failure despite setting aside all donors 60 and up, and a large fraction of 50-59 year-old donors, from this group. Current ECD/SCD definitions warrant review and possible revision.

Adult↗