Mark D Stegall

Mayo Foundation for Medical Education and Research, Scottsdale, AZ, USA

Are you Mark D Stegall?

Claim your profile

Publications (85)408.67 Total impact

  • Article: Identification and Characterization of Kidney Transplants With Good Glomerular Filtration Rate at 1 Year but Subsequent Progressive Loss of Renal Function.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: After the first year after kidney transplantation, 3% to 5% of grafts fail each year but detailed studies of how grafts progress to failure are lacking. This study aimed to analyze the functional stability of kidney transplants between 1 and 5 years after transplantation and to identify initially well-functioning grafts with progressive decline in allograft function. METHODS: The study included 788 adult conventional kidney transplants performed at the Mayo Clinic Rochester between January 2000 and December 2005 with a minimum graft survival and follow-up of 2.6 years. The modification of diet in renal disease equation for estimating glomerular filtration rate (eGFRMDRD) was used to calculate the slope of renal function over time using all available serum creatinine values between 1 and 5 years after transplantation. RESULTS: Most transplants demonstrated good function (eGFRMDRD ≥40 mL/min) at 1 year with positive eGFRMDRD slope between 1 and 5 years after transplantation. However, a subset of grafts with 1-year eGFRMDRD ≥40 mL/min exhibited strongly negative eGFRMDRD slope between 1 and 5 years suggestive of progressive loss of graft function. Forty-one percent of this subset reached graft failure during follow-up, accounting for 69% of allograft failures occurring after 2.5 years after transplantation. This pattern of progressive decline in estimated glomerular filtration rate despite good early function was associated with but not fully attributable to factors suggestive of enhanced antidonor immunity. CONCLUSIONS: Longitudinal analysis of serial estimated glomerular filtration ratemeasurements identifies initially well-functioning kidney transplants at high risk for subsequent graft loss. For this subset, further studies are needed to identify modifiable causes of functional decline.
    Transplantation 10/2012; · 4.00 Impact Factor
  • Article: The role of complement in antibody-mediated rejection in kidney transplantation.
    Mark D Stegall, Marcio F Chedid, Lynn D Cornell
    [show abstract] [hide abstract]
    ABSTRACT: Over the past decade, several studies have suggested that the complement system has an active role in both acute and chronic allograft rejection. These studies have been facilitated by improved techniques to detect antibody-mediated organ rejection, including immunohistological staining for C4d deposition in the allograft and solid-phase assays that identify donor-specific alloantibodies (DSAs) in the serum of transplant recipients. Studies with eculizumab, a humanized monoclonal antibody directed against complement component C5, have shown that activation of the terminal complement pathway is necessary for the development of acute antibody-mediated rejection in recipients of living-donor kidney allografts who have high levels of DSAs. The extent to which complement activation drives chronic antibody-mediated injury leading to organ rejection is less clear. In chronic antibody-mediated injury, early complement activation might facilitate chemotaxis of inflammatory cells into the allograft in a process that later becomes somewhat independent of DSA levels and complement factors. In this Review, we discuss the different roles that the complement system might have in antibody-mediated allograft rejection, with specific emphasis on renal transplantation.
    Nature Reviews Nephrology 10/2012; 8(11):670-8. · 7.09 Impact Factor
  • Article: The impact of terminal complement blockade on the efficacy of induction with polyclonal rabbit antithymocyte globulin in living donor renal allografts.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: Eculizumab, a potent inhibitor of terminal complement activation, appears promising in reducing early antibody-mediated rejection in positive crossmatch kidney transplantation. However, its concomitant use with polyclonal rabbit antithymocyte globulin (rATG) might reduce the efficacy of rATG. This study aimed to evaluate the effect of eculizumab on the efficacy of rATG in vivo and determine the role of complement in rATG-induced lymphocyte cell depletion. PATIENTS AND METHODS: Thirty-six kidney transplant recipients were classified into 3 groups according to induction regime: anti-IL-2 receptor antibody alone induction group (basiliximab, n=8); rATG induction (n=20), and rATG+eculizumab induction group (n=8). Peripheral blood T-cell subsets and NK cells were measured 3-4days after transplant (after 3 doses of rATG). RESULTS: Compared to anti-IL-2 receptor antibody induction group, both groups treated with rATG demonstrated significant depletion of all T-cell subsets (CD3-positive cells) (P<0.0001 for rATG vs. anti-IL-2 receptor antibody induction group; P<0.001 for rATG+eculizumab vs. anti-IL-2 receptor antibody group). However, while T-cell counts were low in all rATG-treated patients, eculizumab treatment resulted in higher peripheral blood T-cell counts in rATG treated patients (P=0.005). Before induction, median total lymphocyte counts were normal for the three study groups. By 1, 4months and 1year, median the total lymphocyte count was normal for the anti-IL-2 receptor antibody group but was below normal range or at the lower edge of normality for rATG and rATG+eculizumab groups. CONCLUSIONS: This small-sample size study suggests that peripheral T cells are depleted by rATG in the presence of terminal complement inhibition. However, eculizumab appears to have a mild inhibitory effect on peripheral blood T-cell depletion by rATG in kidney transplant recipients.
    Transplant Immunology 07/2012; · 1.46 Impact Factor
  • Article: Long-term follow-up of patients with monoclonal gammopathy of undetermined significance after kidney transplantation.
    [show abstract] [hide abstract]
    ABSTRACT: Long-term data regarding kidney transplantation (KTx) patients with monoclonal gammopathy of undetermined significance (MGUS) are scarce. We evaluated the long-term outcomes of these patients in a single-center retrospective study from the Mayo Clinic, Rochester, Minn., USA. Patients who had an MGUS before transplant or developed one after KTx were selected. Monoclonal protein was screened as part of the KTx evaluation by serum protein electrophoresis. Screening for posttransplant lymphoproliferative disorder (PTLD) or MGUS after transplant was not required by protocol. Patients with multiple myeloma, dysproteinemia-related kidney disease or no pretransplant serum protein electrophoresis were excluded. Between 1963 and 2006, 3,518 patients underwent KTx. MGUS was identified in 42 patients, with 23 before transplant and 19 after transplant. Median follow-up for these patients was 8.5 years (range 0.3-37). Four (17.4%) pretransplant MGUS patients developed a hematologic malignancy: 2 smoldering multiple myeloma and 2 PTLD - an Epstein-Barr virus-positive diffuse large cell lymphoma and a Hodgkin lymphoma. None of the 19 patients who developed an MGUS after transplant progressed to multiple myeloma, but 2 (10.5%) developed Epstein-Barr virus-negative T cell lymphoproliferative disorders at 16 and 26 years after transplant. Median survival was 26.1 and 28.0 years for the pretransplant and posttransplant MGUS groups, respectively. Progression from true MGUS to multiple myeloma is rare after KTx. KTx appears safe in true MGUS patients if the monoclonal gammopathy was not the cause of the kidney disease. None of the patients progressed to multiple myeloma, but 2 developed smoldering multiple myeloma and several developed PTLD. Further studies are needed to explain the relationship between MGUS and PTLD.
    American Journal of Nephrology 04/2012; 35(4):365-71. · 2.54 Impact Factor
  • Article: Free fatty acid storage in human visceral and subcutaneous adipose tissue: role of adipocyte proteins.
    [show abstract] [hide abstract]
    ABSTRACT: Because direct adipose tissue free fatty acid (FFA) storage may contribute to body fat distribution, we measured FFA (palmitate) storage rates and fatty acid (FA) storage enzymes/proteins in omental and abdominal subcutaneous fat. Elective surgery patients received a bolus of [1-(14)C]palmitate followed by omental and abdominal subcutaneous fat biopsies to measure direct FFA storage. Long chain acyl-CoA synthetase (ACS) and diacylglycerol acyltransferase activities, CD36, fatty acid-binding protein, and fatty acid transport protein 1 were measured. Palmitate tracer storage (dpm/g adipose lipid) and calculated palmitate storage rates were greater in omental than abdominal subcutaneous fat in women (1.2 ± 0.8 vs. 0.7 ± 0.4 μmol · kg adipose lipid(-1) · min(-1), P = 0.005) and men (0.7 ± 0.2 vs. 0.2 ± 0.1, P < 0.001), and both were greater in women than men (P < 0.0001). Abdominal subcutaneous adipose tissue palmitate storage rates correlated with ACS activity (women: r = 0.66, P = 0.001; men: r = 0.70, P = 0.007); in men, CD36 was also independently related to palmitate storage rates. The content/activity of FA storage enzymes/proteins in omental fat was dramatically lower in those with more visceral fat. In women, only omental palmitate storage rates were correlated (r = 0.54, P = 0.03) with ACS activity. Some adipocyte FA storage factors correlate with direct FFA storage, but sex differences in this process in visceral fat do not account for sex differences in visceral fatness. The reduced storage proteins in those with greater visceral fat suggest that the storage factors we measured are not a predominant cause of visceral adipose tissue accumulation.
    Diabetes 08/2011; 60(9):2300-7. · 8.29 Impact Factor
  • Article: An Important Debate.
    Mark D Stegall, Walter Park, Fernando Cosio
    American Journal of Transplantation 06/2011; · 6.39 Impact Factor
  • Article: Long-term outcomes of patients with light chain amyloidosis (AL) after renal transplantation with or without stem cell transplantation.
    [show abstract] [hide abstract]
    ABSTRACT: Recent advances in the treatment of immunoglobulin light chain amyloidosis (AL) have dramatically improved survival. Kidney transplantation (KTx) has become more common but the long-term outcomes remain unknown and it is the objective of this study. Nineteen patients with AL underwent living (n = 18) or deceased (n = 1) KTx at our institution from 1999 to 2008 (median age 57 years, six women). The primary end points were patient and kidney allograft survival and recurrence of AL in the allograft. The secondary end point was kidney transplant rejection. Outcome data were stratified according to three treatment modalities: renal transplantation followed by autologous stem cell transplantation (ASCT) (Group 1, n = 8), ASCT followed by renal transplantation (Group 2, n = 6) and renal transplantation after complete remission achieved with nonmyeloablative therapy (Group 3, n = 5). The median follow-up was 41.4 months. At the time of study, 79% were still alive. Median graft survival did not differ from median overall survival. There was no difference in survival rates between the treatment groups. Five patients had a cellular rejection. Two of the three patients with a rejection in Group 1 died but neither patient with rejection in Groups 2 and 3. Recurrent amyloidosis was diagnosed by biopsy in one patient in Group 2 (preceding ASCT) and in another patient in Group 3. KTx can be successfully performed in AL patients in complete hematologic response and meet the usual KTx selection criteria. Outcomes appear similar whether hematologic response was achieved with ASCT or by nonmyeloablative therapy.
    Nephrology Dialysis Transplantation 06/2011; 26(6):2032-6. · 3.40 Impact Factor
  • Article: Association of kidney function and metabolic risk factors with density of glomeruli on renal biopsy samples from living donors.
    [show abstract] [hide abstract]
    ABSTRACT: To test the hypothesis that kidney function and metabolic risk factors are associated with glomerular density on renal biopsy samples from healthy adults. This study compared glomerular density with predonation kidney function, blood pressure, and metabolic risk factors in living kidney donors at Mayo Clinic in Rochester, MN, from May 10, 1999, to February 4, 2009. During implantation of the kidney allograft, an 18-gauge core needle biopsy sample of the renal cortex was obtained, sectioned, and examined by pathologists. Glomerular density was determined by the number of glomeruli (normal and sclerotic) divided by area of cortex. The study sample of 1046 kidney donors had a mean of 21 glomeruli (0.8 sclerotic glomeruli) and a glomerular density of 2.3 glomeruli per square millimeter. In a subset of 54 donors, glomerular density inversely correlated with the mean glomerular area (r(s) = -0.28). Independent predictors of decreased glomerular density were older age, increased glomerular filtration rate, family history of end-stage renal disease, increased serum uric acid, and increased body mass index. Increased urine albumin excretion, hypertension, decreased high-density lipoprotein cholesterol, and metabolic syndrome were also associated with decreased glomerular density after age-sex adjustment. These associations were not explained by the presence of glomerulosclerosis, tubular atrophy, interstitial fibrosis, or arteriosclerosis on the renal biopsy sample. In older donors, decreased glomerular density was attenuated by an increased prevalence of glomerulosclerosis and tubular atrophy. Decreased glomerular density is associated with many different kidney function and metabolic risk factors among relatively healthy adults and may represent an early state of increased risk of parenchymal injury.
    Mayo Clinic Proceedings 04/2011; 86(4):282-90. · 5.70 Impact Factor
  • Article: The impact of proteasome inhibition on alloantibody-producing plasma cells in vivo.
    [show abstract] [hide abstract]
    ABSTRACT: Donor specific alloantibody producing plasma cells (DSA-PCs) appear resistant to conventional immunosuppressive agents. This study aimed to determine the impact of pretransplant monotherapy with the proteasome inhibitor bortezomib on DSA-PCs in sensitized renal allograft candidates and to assess if DSA-PC depletion would enhance the efficacy of DSA removal using plasma exchange (PE). Only patients with DSA levels considered too high to successfully undergo transplantation with PE alone were included in this study: i.e. those with a baseline B flow cytometric crossmatch (BFXM) >450 against a potential living donor.Four sensitized patients received 4 doses (1.3 mg/m/dose) of bortezomib and 4 received 16 doses. The number of DSA-PCs was determined pre and post-treatment using an ELISPOT assay. Five of these patients underwent post-treatment PE and their response was compared to 8 highly-sensitized patients (BFXM >450) who underwent PE alone. When considering all 8 patients as one group, bortezomib treatment decreased DSA-PCs in the marrow (mean±SD=16.7±14.5 DSA-PCs/ml pre-treatment vs. 6.2±3.6 DSA-PCs/ml after treatment, P=0.048). In the time frame of the study, bortezomib alone did not decrease serum DSA levels. However, five bortezomib treated patients underwent PE and showed a greater decease in DSA compared to the historical control group of 8 sensitized patients who underwent PE alone (mean decrease in BFXM channel shift=272.6±92.1 with bortezomib vs 95.4±72.2 in PE alone P=0.008). Bortezomib depletes DSA-PCs and appears to potentiate DSA removal by PE in sensitized renal transplant recipients.
    Transplantation 03/2011; 91(5):536-41. · 4.00 Impact Factor
  • Article: The effect of coronary angiography on renal function in preemptive renal transplant candidates.
    [show abstract] [hide abstract]
    ABSTRACT: Increasing numbers of patients undergo preemptive renal transplantation. Obtaining cardiac catheterizations prior to transplantation to screen for coronary artery disease is controversial because of the perceived risk of inducing contrast nephropathy and the need for dialysis in patients with marginal renal function. We sought to examine the true impact of cardiac catheterization on time to dialysis in a cohort of preemptive renal transplant candidates. From a cohort of 376 transplant candidates evaluated preemptively at our program between 2/2001 and 4/2005, 34 patients had positive dobutamine stress echocardiograms. We reviewed the subsequent need for dialysis in these patients. Among candidates undergoing angiography, 8.7% required dialysis within 14 d of contrast administration and 26% eventually needed dialysis prior to transplantation at 5.3 ± 3.7 months after their pre-transplant evaluation. Among patients who did not undergo angiography, 27% needed dialysis prior to transplantation at 2.4 ± 1.8 months after pre-transplant evaluation. Our results demonstrate a low risk of hastening the need for dialysis after coronary angiography in preemptive renal transplant candidates. Undergoing angiography had no effect on the ultimate need for or timing of dialysis initiation. These findings support completion of full cardiac evaluation as indicated for high-risk preemptive renal transplant candidates.
    Clinical Transplantation 11/2010; 25(4):594-9. · 1.67 Impact Factor
  • Source
    Article: Fibrosis with inflammation at one year predicts transplant functional decline.
    [show abstract] [hide abstract]
    ABSTRACT: Lack of knowledge regarding specific causes for late loss of kidney transplants hampers improvements in long-term allograft survival. Kidney transplants with both interstitial fibrosis and subclinical inflammation but not fibrosis alone after 1 year have reduced survival. This study tested whether fibrosis with inflammation at 1 year associates with decline of renal function in a low-risk cohort and characterized the nature of the inflammation. We studied 151 living-donor, tacrolimus/mycophenolate-treated recipients without overt risk factors for reduced graft survival. Transplants with normal histology (n = 86) or fibrosis alone (n = 45) on 1-year protocol biopsy had stable renal function between 1 and 5 years, whereas those with both fibrosis and inflammation (n = 20) exhibited a decline in GFR and reduced graft survival. Immunohistochemistry confirmed increased interstitial T cells and macrophages/dendritic cells in the group with both fibrosis and inflammation, and there was increased expression of transcripts related to innate and cognate immunity. Pathway- and pathologic process-specific analyses of microarray profiles revealed that potentially damaging immunologic activities were enriched among the overexpressed transcripts (e.g., Toll-like receptor signaling, antigen presentation/dendritic cell maturation, IFN-γ-inducible response, cytotoxic T lymphocyte-associated and acute rejection-associated genes). Therefore, the combination of fibrosis and inflammation in 1-year protocol biopsies associates with reduced graft function and survival as well as a rejection-like gene expression signature, even among recipients with no clinical risk factors for poor outcomes. Early interventions aimed at altering rejection-like inflammation may improve long-term survival of kidney allografts.
    Journal of the American Society of Nephrology 11/2010; 21(11):1987-97. · 9.66 Impact Factor
  • Article: The (re)emergence of B cells in organ transplantation.
    Mark D Stegall, Suresh Raghavaiah, James M Gloor
    [show abstract] [hide abstract]
    ABSTRACT: To outline recent advances in our understanding of the role of B cells in transplantation. While T-cell-mediated alloimmunity has been largely controlled using immunosuppression, the role of B cells in transplantation is just beginning to be understood. Recent studies have outlined some of the important clinical issues involving antibody including early acute humoral rejection and late transplant glomerulopathy. In addition, recent studies have identified bone-marrow-derived long-lived plasma cells that appear to be a major source of donor-specific alloantibody in sensitized renal transplant recipients. New agents are being tested that deplete these cells in vitro and in vivo. Memory B cells appear to be important in early acute humoral rejection, but few basic studies have been performed. Finally, recent studies involving patients undergoing tolerogenic regimens suggest that T-cell tolerance does not always convey tolerance in naive B cells. Several B cell types have clear and specific roles in transplant recipients. Although our understanding of B cells in transplantation has improved, important gaps remain.
    Current opinion in organ transplantation 08/2010; 15(4):451-5. · 1.22 Impact Factor
  • Article: The association between age and nephrosclerosis on renal biopsy among healthy adults.
    [show abstract] [hide abstract]
    ABSTRACT: Chronic kidney disease is common with older age and is characterized on renal biopsy by global glomerulosclerosis, tubular atrophy, interstitial fibrosis, and arteriosclerosis. To see whether the prevalence of these histologic abnormalities in the kidney increases with age in healthy adults and whether histologic findings are explained by age-related differences in kidney function or chronic kidney disease risk factors. Cross-sectional study. Mayo Clinic, Rochester, Minnesota, from 1999 to 2009. 1203 adult living kidney donors. Core-needle biopsy of the renal cortex obtained during surgical implantation of the kidney, and medical record data of kidney function and risk factors obtained before donation. The prevalence of nephrosclerosis (> or =2 chronic histologic abnormalities) was 2.7% (95% CI, 1.1% to 6.7%) for patients aged 18 to 29 years, 16% (CI, 12% to 20%) for patients aged 30 to 39 years, 28% (CI, 24% to 32%) for patients aged 40 to 49 years, 44% (CI, 38% to 50%) for patients aged 50 to 59 years, 58% (CI, 47% to 67%) for patients aged 60 to 69 years, and 73% (CI, 43% to 90%) for patients aged 70 to 77 years. Adjustment for kidney function and risk factor covariates did not explain the age-related increase in the prevalence of nephrosclerosis. Kidney donors are selected for health and lack the spectrum or severity of renal pathologic findings in the general population. Kidney function and chronic kidney disease risk factors do not explain the strong association between age and nephrosclerosis in healthy adults. National Institutes of Health, U.S. Public Health Service.
    Annals of internal medicine 05/2010; 152(9):561-7. · 16.73 Impact Factor
  • Article: Significance and implications of capillaritis during acute rejection of kidney allografts.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND.: Anti-human leukocyte antigen antibodies (a-HLA) cause graft injury identified by C4d in peritubular capillaries. We investigated whether a-HLA relate to episodes of C4d negative acute rejection (AR). METHODS.: We analyzed 878 kidney recipients transplanted from January 2000 to December 2006. Pretransplant, 36% of these crossmatch negative recipients had a-HLA measured by solid phase assays. RESULTS.: AR occurred in 154 patients (18%) and 11 of them (9.4%) were C4d+. Forty-six percent of ARs were diagnosed by protocol biopsy. The risk of C4d-AR was increased in patients with a-HLA class I with donor specificity (DSA-I) (hazard ratio=1.519; confidence interval, 1.02-2.26; P=0.039). DSA-II were not associated with an increased risk of C4d-AR. The relationship between DSA-I and C4d-AR was independent of recipient age, BK nephropathy, and HLA mismatches. Compared with DSA-, in DSA+ recipients C4d-AR were most often histologically "borderline." DSA+ was associated with capillaritis in the biopsy (glomerulitis, 6.1% vs. 32%, P=0.003; peritubular capillaritis: 13% vs. 40%, P=0.0009). Compared with no AR, C4d-AR with capillaritis was associated with reduced graft survival (hazard ratio=4.164; confidence interval, 1.763-9.832; P=0.001), independent of other variables. This association was observed even in the cases of borderline AR. CONCLUSIONS.: DSA-I increases the risk of C4d-AR. The presence of DSA-I or II is associated with capillaritis during AR. Capillaritis is associated with reduced graft survival.
    Transplantation 03/2010; 89(9):1088-94. · 4.00 Impact Factor
  • Article: Sensitized renal transplant recipients: current protocols and future directions.
    James Gloor, Mark D Stegall
    [show abstract] [hide abstract]
    ABSTRACT: The identification of suitable donor kidneys for transplant candidates with high levels of circulating antibodies against human leukocyte antigen (HLA) is a major challenge and results in prolonged waiting times for transplantation. Technological advances in antibody characterization have permitted a more comprehensive assessment of anti-HLA antibody activity, as well as providing new insights into the clinical effect of HLA antibody class and specificity. Protocols have been developed that enable successful transplantation in patients with donor-specific antibodies (anti-HLA antibodies reactive against their donors). These protocols provide satisfactory early to intermediate-term allograft survival, and constitute an important advance in transplantation. Nevertheless, acute antibody-mediated rejection (AMR) remains a significant challenge, occurring in 20-50% of antibody-incompatible kidney transplantations. Although therapy directed toward lowering donor-specific antibody activity seems to be successful in reversing acute AMR, this condition still has an important negative impact on allograft survival. In addition, subclinical AMR seems to complicate a substantial proportion of positive-crossmatch transplantations even in the absence of allograft dysfunction, and may result in chronic histological abnormalities and shortened allograft function. New interventions for preventing acute AMR, such as anti-C5 antibody-mediated complement blockade and proteasome inhibitor-mediated plasma cell depletion, are promising therapeutic avenues currently under investigation.
    Nature Reviews Nephrology 03/2010; 6(5):297-306. · 7.09 Impact Factor
  • Article: Prevalence of renal artery and kidney abnormalities by computed tomography among healthy adults.
    [show abstract] [hide abstract]
    ABSTRACT: Management of incidental renal artery and kidney abnormalities in patients undergoing computed tomography scans is a clinical challenge because their frequency in healthy subjects has not been precisely estimated. Therefore, the prevalence and management of these abnormalities were determined among a large cohort of potential kidney donors undergoing protocol evaluations. All patients at the Mayo Clinic who underwent computed tomographic angiography and urography as part of their kidney donor evaluation between 2000 and 2008 were identified. Radiographic reports were abstracted for abnormalities of the renal arteries and kidneys. The prevalence of radiographic abnormalities was stratified by age and gender, and the effect on approval for kidney donation was determined. Among 1957 potential kidney donors, the mean +/- SD age was 43 +/- 12 years, and 58% were women. The most common abnormalities were kidney stones (11%), focal scarring (3.6%), fibromuscular dysplasia (2.8%), and other renal artery narrowing or atherosclerosis (5.3%). Fibromuscular dysplasia, focal scarring, parenchymal atrophy, and upper tract dilation were more common in women. Renal artery narrowing, focal scarring, and indeterminate masses increased with age. Overall, 25% of potential donors had at least one abnormality. However, these incidental radiographic abnormalities contributed to exclusion from donation in only 6.7% of potential donors. Incidental radiographic abnormalities of the renal arteries and kidneys are common. The majority of imaging findings are not perceived to be harmful enough to prevent kidney donation, but future studies are needed to determine their clinical relevance.
    Clinical Journal of the American Society of Nephrology 03/2010; 5(3):431-8. · 5.23 Impact Factor
  • Article: Epidemiology of infections requiring hospitalization during long-term follow-up of pancreas transplantation.
    [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND.: Pancreas transplantation (PT) provides the best glycemic control option for diabetes mellitus but is associated with significant morbidities related to infectious disease. METHODS.: We performed a retrospective study of a cohort of consecutive PT recipients in whom PT was performed from 1998 to 2006 (n=216) and followed up them until July 2008. Data regarding infections, rejection, infection chemoprophylaxis, graft failure, absolute lymphocyte counts (ALCs), and mortalities were collected. RESULTS.: Simultaneous pancreas and kidney, pancreas transplantation alone, and pancreas after kidney (PAK) transplantations were performed in 42, 67, and 107 patients, with a mean (standard deviation) age at transplantation of 46.8 (8.03), 40.6 (10.1), and 43.7 (8.19) years. Of the simultaneous pancreas and kidney, pancreas transplantation alone, and PAK transplant recipients, 54.7%, 37.3%, and 58.8% were men. Overall, 63% developed a serious infection during the median follow-up of 6.4 years. Mean (range) number of infectious episodes was 2.3 (1-12), with mostly bacterial infections both within (68%) and after 1 year (78%). Incidence of bacterial and viral infections was greatest in the first 3 months after transplantation. Fungal infections were more constant. Bladder exocrine drainage was associated with higher risk of infection (hazard ratio=2.5, P<0.001). Infection within the first 3 months after transplantation was related to higher mortality after the first 3 months (hazard ratio=3.19). ALC was associated with the risk of first infections (P=0.005) and bacterial infections (P<0.001). CONCLUSIONS.: Incidence of infections after PT was 63% and mostly bacterial. Bladder drainage increases infection risk and low ALC partially predicts episodes. Limitations include retrospective design, unequal composition of PT groups, and lack of data between kidney and PT for PAK.
    Transplantation 02/2010; 89(9):1126-33. · 4.00 Impact Factor
  • Article: Antibody-mediated rejection following transplantation from an HLA-identical sibling.
    [show abstract] [hide abstract]
    ABSTRACT: Putative antibody-mediated rejection (AMR) in HLA-identical sibling transplantation has rarely been reported and occurred before routine calcineurin inhibitor use. A 29-year-old male developed allograft dysfunction following an HLA-identical renal transplant from his sibling. A pretransplant panel-reactive antibody (PRA) was elevated, pre-transplant crossmatch was negative and no donor-specific antibody (DSA) was identified. Induction with alemtuzumab was followed by maintenance immunosuppression with corticosteroids, tacrolimus and mycophenolate. A biopsy for allograft dysfunction suggested AMR, but DSA could not be detected. Treatment for rejection was transiently successful. Undetectable minor histocompatibility antibodies may have contributed.
    Nephrology Dialysis Transplantation 10/2009; 25(1):307-10. · 3.40 Impact Factor
  • Article: Kidney transplantation for primary focal segmental glomerulosclerosis: outcomes and response to therapy for recurrence.
    [show abstract] [hide abstract]
    ABSTRACT: For a subset of adults and children with primary focal segmental glomerulosclerosis (FSGS), proteinuria and renal dysfunction recur after kidney transplantation (KTx). Predicting recurrence and response to plasmapheresis (PP) or other interventions remains problematic. The prevalence, recurrence rate, outcomes, and treatment responses of patients with FSGS were determined among 1573 KTx recipients. Although 5.0% carried some diagnosis of FSGS, only 1.9% (n=30) met strict diagnostic criteria for primary FSGS including biopsy-proven FSGS, lack of secondary factors, negative family history, and progression to end-stage renal disease within 10 years. Of these, 47% had recurrent FSGS compared with 8% of those not meeting strict criteria (P<0.001). Recurrence was more common in children compared with adults (86% vs. 35%, P=0.01). Graft survival was lower for recipients with primary FSGS compared with all others and inferior graft survival was attributable to recurrent FSGS. Fourteen patients received PP preemptively (pre-KTx) or therapeutically (post-KTx) for recurrent disease. Four pediatric patients additionally received anti-CD20 (rituximab) therapy. Of the different treatment approaches, only PP combined with rituximab was associated with prolonged remission of proteinuria. The results indicate that patients at high risk for FSGS recurrence can be identified and may benefit from carefully planned peritransplant interventions.
    Transplantation 05/2009; 87(8):1232-9. · 4.00 Impact Factor
  • Article: Pulmonary hypertension is associated with reduced patient survival after kidney transplantation.
    [show abstract] [hide abstract]
    ABSTRACT: Pulmonary hypertension (PH) is common in patients on dialysis where it is associated with reduced survival. The possible association between PH and kidney transplant recipient survival has not been previously evaluated. In this retrospective study, we screened for PH pretransplant in 215 transplant candidates using cardiac echocardiography and measurements of right ventricular systolic pressure (RVSP). Sixty-eight percent of patients had normal RVSP (<35 mm Hg), 47 (22%) had mild to moderately elevated RVSP (36-50), and 22 (10%) had markedly elevated RVSP more than 50 suggestive of severe PH. Time on dialysis was the strongest correlate of an elevated RVSP (r=0.253, P<0.001) and this relationship was independent of other variables. Elevated RVSP was observed in 25%, 25%, 38%, and 58% of patients not on dialysis, on dialysis for less than 1 year, more than 1 to 2 years, or more than 2 years, respectively. An RVSP more than 50 was associated with significantly reduced posttransplant survival (hazard ratio =3.75 [1.17-11.97], P=0.016). This relationship seemed to be independent of other variables including older age, reduced left ventricular ejection fraction, low serum albumin, and delayed graft function. These analyses suggest for the first time that pretransplant PH correlates with patient survival after kidney transplantation.
    Transplantation 12/2008; 86(10):1384-8. · 4.00 Impact Factor