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Dive into the research topics where Scott R. Johnson is active.

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Featured researches published by Scott R. Johnson.


American Journal of Transplantation | 2007

The Medical Evaluation of Living Kidney Donors: A Survey of US Transplant Centers

Didier A. Mandelbrot; Martha Pavlakis; Gabriel M. Danovitch; Scott R. Johnson; Seth J. Karp; Khalid Khwaja; Douglas W. Hanto; James R. Rodrigue

The use of living donors for kidney transplantation in the United States is common, and long‐term studies have demonstrated the safety of donation by young, healthy individuals. However, transplant programs have little data to guide them in deciding which donors are unacceptable, and which characteristics are associated with kidney disease or poor psychosocial outcomes after donation. To document current practices in evaluating potential donors, we surveyed all US kidney transplant programs. Compared to a survey 12 years ago, medical criteria for donation are more inclusive in several areas. All responding programs now accept living unrelated donors. Most programs no longer have an upper age limit to be eligible. Programs are now more likely to accept donors with treated hypertension, or a history of kidney stones, provided that certain additional criteria are met. In contrast, medical criteria for donation are more restrictive in other areas, such as younger donor age and low creatinine clearance. Overall, significant variability remains among transplant programs in the criteria used to evaluate donors. These findings highlight the need for more data on long‐term outcomes in various types of donors with potential morbidities related to donation.


American Journal of Transplantation | 2007

Evaluating living kidney donors: relationship types, psychosocial criteria, and consent processes at US transplant programs.

James R. Rodrigue; Martha Pavlakis; Gabriel M. Danovitch; Scott R. Johnson; Seth J. Karp; Khalid Khwaja; Douglas W. Hanto; Didier A. Mandelbrot

We conducted a survey of 132 US kidney transplant programs to examine how they evaluate and select potential living kidney donors, focusing on donor‐recipient relationships, psychosocial criteria, and consent processes. There is heterogeneity in donor‐recipient relationships that are considered acceptable, although most programs (70%) will not consider publicly solicited donors. Most programs (75%) require a psychosocial evaluation for all potential living donors. Most programs agree that knowledge of financial reward (90%), active substance abuse (86%), and active mental health problems (76%) are absolute contraindications to donation. However, there is greater variability in how other psychosocial issues are considered in the selection process. Consent processes are highly variable across programs: donor and recipient consent for the donor evaluation is presumed in 57% and 76% of programs, respectively. The use of 13 different informed consent elements varied from 65% (alternative donation procedures) to 86% (description of evaluation, surgery and recuperative period) of programs. Forty‐three percent use a ‘cooling off’ period. Findings demonstrate high variability in current practice regarding acceptable donor‐recipient relationships, psychosocial criteria, and consent processes. Whether greater consensus should be reached on these donor evaluation practices, especially in the context of more expansive use of living donor kidney transplantation, is discussed.


Transplantation | 2008

Donor postextubation hypotension and age correlate with outcome after donation after cardiac death transplantation.

Karen J. Ho; Christopher D. Owens; Scott R. Johnson; Khalid Khwaja; Michael P. Curry; Martha Pavlakis; Didier A. Mandelbrot; James J. Pomposelli; Shimul A. Shah; Reza F. Saidi; Dicken S.C. Ko; Sayeed K. Malek; John Belcher; David Hull; Stefan G. Tullius; Richard B. Freeman; Elizabeth A. Pomfret; James F. Whiting; Douglas W. Hanto; Seth J. Karp

Background. Compared with standard donors, kidneys recovered from donors after cardiac death (DCD) exhibit higher rates of delayed graft function (DGF), and DCD livers demonstrate higher rates of biliary ischemia, graft loss, and worse patient survival. Current practice limits the use of these organs based on time from donor extubation to asystole, but data to support this is incomplete. We hypothesized that donor postextubation parameters, including duration and severity of hemodynamic instability or hypoxia might be a better predictor of subsequent graft function. Methods. We performed a retrospective examination of the New England Organ Bank DCD database, concentrating on donor factors including vital signs after withdrawal of support. Results. Prolonged, severe hypotension in the postextubation period was a better predictor of subsequent organ function that time from extubation to asystole. For DCD kidneys, this manifested as a trend toward increased DGF. For DCD livers, this manifested as increased rates of poor outcomes. Maximizing the predictive value of this test in the liver cohort suggested that greater than 15 min between the time when the donor systolic blood pressure drops below 50 mm Hg and flush correlates with increased rates of diffuse biliary ischemia, graft loss, or death. Donor age also correlated with worse outcome. Conclusions. Time between profound instability and cold perfusion is a better predictor of outcome than time from extubation to asystole. If validated, this information could be used to predict DGF after DCD renal transplant and improve outcomes after DCD liver transplant.


Transplantation | 2009

Practices and Barriers in Long-term Living Kidney Donor Follow-up: A Survey of U.s. Transplant Centers

Didier A. Mandelbrot; Martha Pavlakis; Seth J. Karp; Scott R. Johnson; Douglass W. Hanto; James R. Rodrigue

Background. Many have called for more comprehensive follow-up of living kidney donors, both for the donor’s benefit and to establish a high-quality database of donor outcomes. United Network for Organ Sharing currently requires transplant centers to report donor follow-up information at several time points after donation, but little is known about how frequently this information is obtained, or which barriers exist to compliance with United Network for Organ Sharing requirements. Methods. To assess practices and barriers in providing follow-up care to living donors, we sent a questionnaire to all program directors at U.S. transplant centers. Results. Few transplant centers are currently seeing donors for long-term follow-up. Many centers recommend that donor follow-up care be provided by primary care physicians, but follow-up information is rarely received from primary care physicians. The main barriers to collecting more complete information are donor inconvenience, costs, and lack of reimbursement to the transplant center for providing follow-up care. Conclusions. Significant changes are required to improve long-term donor follow-up by U.S. transplant centers.


American Journal of Transplantation | 2006

Retransplantation After Post‐Transplant Lymphoproliferative Disorders: An OPTN/UNOS Database Analysis

Scott R. Johnson; Wida S. Cherikh; H. M. Kauffman; Martha Pavlakis; Douglas W. Hanto

Post‐transplant lymphoproliferative disorders (PTLD) are a life‐threatening complication of immunosuppressive therapy. Retransplantation of survivors remains controversial. The Organ Procurement and Transplant Network/United Network for Organ Sharing database was reviewed for individuals who developed PTLD and underwent retransplant from 1987 through 2004. Sixty‐nine retransplants have been performed: 27 kidney, 22 liver, 9 lung, 6 heart, 4 intestine and 1 pancreas. At first transplant, most subjects (63.8%) were <17 years of age and was similar at retransplant with 50.7% less than 17 years. Time from transplant to PTLD was <1 year in 33.3%, 1–3 years in 21.7%, 3–5 years in 21.7%, 5–10 years in 21.7% and >10 years in 1.4%. Time from PTLD to retransplant was <1 year in 24.6%, 1–3 years in 37.7%, 3–5 years in 17.4% and 5–10 years in 20.3%. Induction agents were used in 21.7% of first and 47.8% of retransplants. Immunosuppression for first transplant was cyclosporine (CSA) in 55.1%, tacrolimus (TAC) in 27.5% versus CSA in 26.1%, TAC in 66.7% of retransplants. At last follow‐up, patient and graft survival are 85.5% and 73.9%, respectively. Most subjects retransplanted after PTLD are <17 years on TAC‐based immunosuppression. Patient/graft survival is excellent and retransplantation in PTLD subjects should be considered acceptable.


American Journal of Transplantation | 2007

Primary Nonfunction (PNF) in the MELD Era: An SRTR Database Analysis

Scott R. Johnson; S. Alexopoulos; Michael P. Curry; Douglas W. Hanto

PNF following liver transplantation (LT) is an infrequent but life‐threatening complication. Liver allocation under MELD is based upon recipient severity of illness, a known risk factor for the occurrence of PNF. The incidence of PNF since the application of MELD has not previously been reported. The SRTR database was studied since inception of MELD until September 2004 for all adult recipients of deceased donor LT. PNF was defined as graft loss or death within 14 days of LT secondary to PNF or without defined cause.


Transplantation | 2006

Clinical results of an organ procurement organization effort to increase utilization of donors after cardiac death.

James F. Whiting; Francis L. Delmonico; Paul E. Morrissey; Giacomo Basadonna; Scott R. Johnson; Lewis Wd; Richard J. Rohrer; O'Connor K; James Bradley; Lovewell Td; George S. Lipkowitz

Background. To stimulate organ donation, an organ procurement organization (OPO)-wide effort was undertaken to increase donors after cardiac death (DCD) over a 5-year period. This included commonality of protocols, pulsatile perfusion of kidneys, centralization of data and a regional allocation variance designed to minimize cold ischemia times and encourage adoption of DCD protocols at transplant centers. Results. In one OPO, eight centers initiated DCD programs in 11 hospitals. A total of 52 DCD donors were procured, increasing from four in 1999 to 21 in 2003. Eleven donors had care withdrawn in the operating room, whereas 41 had care withdrawn in the ICU. In all, 91 patients received renal transplants from these 52 donors (12 kidneys discarded, one double transplant), whereas 5 patients received liver transplants. One-, two-, and three-year kidney graft survival rates were 90%, 90%, and 82%, respectively. Fifty-five percent of patients needed at least one session of hemodialysis postoperatively. Mean recipient hospital length of stay was 11.1±6 days. Mean creatinine levels at 3, 6, 12, and 24 months were 1.65, 1.40, 1.41, and 1.40, respectively. Conclusions. DCD donors can be an important source of donor organs and provide excellent overall outcomes. Regional cooperation and a prospectively considered allocation and distribution system are important considerations in stimulating DCD programs.


Journal of Gastrointestinal Surgery | 2004

Clinical characteristics, treatment, and outcome of pancreatic schwannomas

Charudutt Paranjape; Scott R. Johnson; Khalid Khwaja; Harvey Goldman; Jonathan B. Kruskal; Douglas W. Hanto

This article involves the study of a patient with a rare benign schwannoma in the body of the pancreas. After reviewing 39 patient cases previously reported in the literature, a discussion of the schwannoma with regard to clinical presentation, diagnosis, and treatment is examined. A review of the patient’s chart was performed along with a review of the literature using a Medline search. Translations were performed whenever necessary. There are 23 reports of 29 patient cases of pancreatic schwannomas in English and European literature and one report of 10 patient cases in the Japanese literature. The mean age was 57.75 years (range 32–89) and the male-to-female (M:F) ratio was 17:23. The mean reported size was 8.79 cm. The lesion was located in the head in 16 patients (40%), the body in 8 patients (20%), the body and tail in 8 patients (20%), the tail in 6 patients (15%), the head and body in 1 patient (2.5%), and the location was not specified in 1 patient (2.5%). Of the English and European patients, 11 out of 30 patients (36.7%) exhibited solid tumors and 14 out of 30 patients (46.7%) exhibited cystic tumors. The majority of the tumors (35 out of 40) were benign, but there were.ve reported malignancies. There were no deaths or recurrences reported with a follow-up of 18.68 months ± 24.09 (range 3–108 months). Pancreatic schwannomas are rare, and the preoperative diagnosis is difficult. Intraoperative frozen section can confirm the diagnosis of a benign schwannoma. Enucleation of the tumor from the surrounding parenchyma is recommended, if possible. Patients undergoing resection indicate an excellent long-term prognosis.


Clinical Transplantation | 2005

Older living donors provide excellent quality kidneys: a single center experience (older living donors).

Scott R. Johnson; Khalid Khwaja; Martha Pavlakis; Anthony P. Monaco; Douglas W. Hanto

Abstract:  Background:  The role of advanced age live donors remains controversial because of decline in glomerular filtration rate and perceived increased risks of perioperative complications.


Clinical Transplantation | 2011

A cross‐sectional study of fatigue and sleep quality before and after kidney transplantation

James R. Rodrigue; Didier A. Mandelbrot; Douglas W. Hanto; Scott R. Johnson; Seth J. Karp; Martha Pavlakis

Rodrigue JR, Mandelbrot DA, Hanto DW, Johnson SR, Karp SJ, Pavlakis M. A cross‐sectional study of fatigue and sleep quality before and after kidney transplantation.
Clin Transplant 2011: 25: E13–E21.

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Douglas W. Hanto

Beth Israel Deaconess Medical Center

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Martha Pavlakis

Beth Israel Deaconess Medical Center

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Seth J. Karp

Vanderbilt University Medical Center

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Didier A. Mandelbrot

University of Wisconsin-Madison

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Khalid Khwaja

Beth Israel Deaconess Medical Center

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Michael P. Curry

Beth Israel Deaconess Medical Center

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James R. Rodrigue

Beth Israel Deaconess Medical Center

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Amy Evenson

Beth Israel Deaconess Medical Center

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