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Lloyd E Ratner

Publications and source records attributed to Lloyd E Ratner.

28 records · Page 2Linked to original sources
PubMed2003

Demographics of 353 laparoscopic renal donor and recipient pairs at the Johns Hopkins Medical Institutions.

BACKGROUND AND PURPOSE: The demographics of laparoscopic donor nephrectomy (LDN) have not been characterized in detail. The aim of this study was to review our LDN experience with respect to donor and recipient demographic characteristics and trends. PATIENTS AND METHODS: Over a 6-year period, 353 patients underwent LDN. A retrospective chart review was performed to identify the donor and recipient demographic characteristics and trends associated with the procedure. RESULTS: Among the donors, the mean age was 41 years, with a predominance of females (59.2%), whites (76.2%), and blood relations (72%). Siblings were the most common related-donor-to-recipient relationship, and spouses were the most common unrelated relationships. Among the recipients, the mean age was 43 years, with a predominance of males (58.4%), whites (73.7%), and dialysis-dependent patients (55%). Diabetes mellitus and hypertension were the most common causes of end-stage renal failure. With the introduction of laparoscopy, there was a nearly twofold increase in the total number of live renal donations, and there was a significant expansion in the unrelated-donor pool. CONCLUSIONS: Laparoscopic harvest of donated kidneys is associated with new trends that may help alleviate the current organ shortage.

Adolescent↗
PubMed2002

C4d staining of perioperative renal transplant biopsies.

BACKGROUND: Deposition of C4d in peritubular capillaries (PTCs) has been shown to be a sensitive marker for antibody-mediated (humoral) rejection in renal transplant biopsies. Some studies also suggest that C4d in PTCs is specific for humoral rejection or, at least, for the presence of donor-specific antibodies. However, in other studies, PTC C4d deposits were noted in more than 40% of renal transplant biopsies performed for graft dysfunction and capillary C4d deposition in heart transplants may result from ischemic injury. METHODS: To test the specificity of C4d staining as a marker for acute humoral rejection ACR in renal allografts, indirect immunofluorescence using a monoclonal anti-C4d antibody and a fluorescein-isothiocyanate-conjugated secondary antibody was performed on cryostat sections of 90 renal transplant biopsies, including 35 pairs of preimplantation and 1-hr postreperfusion biopsies of the same graft, postreperfusion biopsies of 12 additional grafts, and 8 positive controls (biopsies with known C4d-positive AHR). Eighteen grafts were cadaveric, 17 grafts were liviing-related, and 12 grafts were living-unrelated (excluding controls). Included in these grafts were 13 grafts that developed AHR 3 to 34 days posttransplantation. RESULTS: Only 2 of 82 perioperative biopsies showed C4d staining in PTCs. Both perioperative biopsies were postreperfusion biopsies of grafts diagnosed with AHR 5 and 34 days posttransplantation, respectively, and, in each case, the recipient had been treated with plasmapheresis before transplantation because of a positive crossmatch (cytotoxic and flow cytometric) and continued to have a weakly positive flow crossmatch at the time of transplantation. In one biopsy, C4d staining was focal, and in the other biopsy, it was diffuse; in both biopsies, C4d staining was relatively mild (1+ on a 0-4+ scale). No C4d staining was noted on preimplantation biopsies of each graft. All biopsies that contained glomeruli showed linear capillary loop or blotchy mesangial staining, or both, which was similar in prereperfusion and postreperfusion biopsies. All positive controls showed diffuse C4d staining in PTCs. CONCLUSIONS: C4d staining in PTCs may be seen as early as 1 hr posttransplantation in some recipients with low levels of antidonor antibodies. However, this was not observed as a feature of ischemic or ischemia-reperfusion injury in perioperative renal transplant biopsies, including those of cadaveric grafts with cold ischemia times of as long as 41 hr.

Biomarkers↗
PubMed2002

Determinants of willingness to donate living related and cadaveric organs: identifying opportunities for intervention.

BACKGROUND: Although low rates of cadaveric organ donation have been attributed to potential cadaveric donors' concerns regarding their religious beliefs and mistrust of the health care system, it is unclear whether similar concerns are important to potential living related donors. It is also not known which factors might be most responsible for low rates of cadaveric and living related donation among the general public. METHODS: We conducted a cross-sectional study of households in Maryland, using a standardized telephone questionnaire, to assess factors associated with willingness to donate cadaveric and living related organs. We compared factors (demographic, cultural, attitudinal, and clinical) related to willingness to donate cadaveric organs with factors related to willingness to donate living related organs. In multivariate analyses, we assessed the independent relation of factors to willingness to donate cadaveric and living related organs, and we assessed the relative importance of these factors in explaining variation in the general public's willingness to donate. RESULTS: Of 385 participants (84% of randomized homes), 254 (66%) were extremely willing to donate to a sibling but only 179 (47%) had designated themselves a cadaveric donor on their drivers' licenses. In bivariate analysis, older age, comorbid conditions, mistrust in hospitals, and concerns about discrimination in hospitals were statistically significantly associated with less willingness to donate living related organs, although African-Americans, older age, lower education, lack of insurance, unemployment, comorbid conditions, and religion/spirituality were associated with less willingness to donate cadaveric organs. After adjusting for potential confounders, only mistrust in hospitals and concerns about discrimination remained strongly and independently associated with 50 to 60% less odds of willingness to donate living related organs [[relative odds [95% confidence intervals (CI)]: 0.4 (0.2-0.7) to 0.5 (0.3-1.0) and 0.4 (0.2-0.9), respectively]] although presence of dependents was associated with 70% higher odds of willingness to donate living related organs [relative odds (95% CI): 1.7 (1.0-3.0)]. In contrast, older age, employment status, religion/spirituality, and mistrust in hospitals were associated with 50 to 90% less odds of willingness to donate living related organs cadaveric organs [relative odds (95% CI): 0.3 (0.1-0.8), 0.4(0.2-0.8), 0.1 (0.1- 0.5) to 0.5 (0.2-0.9), and 0.3 (0.2-0.6), respectively]. Mistrust in hospitals and concerns about the surgical donation procedure contributed most to the variation in willingness to be a living related donor, although race contributed most to the variation in willingness to be a cadaveric donor. CONCLUSIONS: Many factors affect the general public's willingness to donate organs, but their relative contribution is different for living related versus cadaveric donation. Efforts to improve organ donation rates should be directed toward factors that are most important in explaining the existing variation in willingness to donate.

Adult↗
PubMed2002

Laparoscopic donor nephrectomy in the elderly patient.

OBJECTIVES: To evaluate retrospectively the outcome of laparoscopic donor nephrectomy in patients aged 65 years or older, because data regarding tolerance profile and renal allograft outcome of laparoscopic donor nephrectomy in the elderly patient are lacking. METHODS: Since February 1995, 6 patients aged 65 years or older underwent laparoscopic donor nephrectomy for living-related renal transplantation. Patient demographic, intraoperative, and postoperative parameters, as well as renal allograft outcome, were evaluated. RESULTS: The median donor age was 69.5 years (range 65 to 74), and the median American Society of Anesthesiologists score was 2 (range 2 to 3). The median operative time was 240 minutes (range 183 to 298), with a median blood loss of 300 mL (range 150 to 400). No intraoperative complications or open conversions occurred. Postoperatively, the median time to resumption of oral intake was 1 day (range 1 to 3), and the median hospital stay was 3 days (range 2 to 4). The median narcotic analgesic requirement was 17 mg (range 11 to 27) morphine sulfate equivalent, and the median convalescence was 2 weeks (range 1 to 4). The 1-year renal allograft survival was 100% (n = 6). CONCLUSIONS: Laparoscopic donor nephrectomy is well tolerated by the elderly patient and provides satisfactory patient and renal allograft outcome. Although our sample size was small, it appears that laparoscopy is an acceptable modality for renal donation in the elderly population.

Adult↗
PubMed2002

Renovascular complications of laparoscopic donor nephrectomy.

OBJECTIVES: To review the operative renovascular injuries related to our laparoscopic donor nephrectomy experience, since management of intraoperative renovascular complications during laparoscopic nephrectomy can present a serious challenge. METHODS: During a 6-year period, 353 patients underwent laparoscopic donor nephrectomy. A retrospective chart review was performed to identify and evaluate the renovascular complications associated with the procedure. RESULTS: Eight cases (2.3%) of renovascular complications were identified. Vascular injury involved the renal artery in 6 cases and the renal vein in 2 cases. The etiologies included endovascular GIA stapling failure (n = 2), surgical clip dislodgment (n = 2), and vessel laceration during dissection or stapling (n = 4). Open conversion was necessary in 6 cases (75%). No patient mortality or allograft loss occurred. CONCLUSIONS: Laparoscopic donor nephrectomy is associated with a low incidence of renovascular complications. Laparoscopic or open surgical management may be required when problems arise to optimize donor safety and allograft survival.

Female↗
PubMed2002

The general public's concerns about clinical risk in live kidney donation.

Difficulty in attracting live kidney donors may be related to fears regarding both the surgical procedure for kidney harvesting and future failure of the remaining kidney. We conducted a cross-sectional study of households in Maryland to identify public disincentives to living related kidney donation. In multivariate analyses, we assessed the independent effects of several factors on willingness to donate a kidney to a sibling. We also assessed thresholds for factors above which persons would not donate a kidney. Of 385 participants, 66% were extremely willing to donate to a sibling. After adjustment, those who considered the length of a hospital stay, out-of-pocket expenses, size and appearance of a scar, the time it takes to get to the transplant center, and the donor risk of developing kidney failure very important had 50-60% less odds of being extremely willing to donate. Median acceptable levels for risk of complications, hospital stay, compensated and uncompensated time from work, time requiring pain medications, and out-of-pocket expenses were greater than levels from clinical evidence regarding both laparoscopic and open nephrectomy. Unrealistic concerns among the general public regarding live donation may serve as potential disincentives to donation. Efforts to educate the public regarding live donation might help assuage fears and attract those who may not otherwise donate.

Adult↗
PubMed2002

Understanding disparities in donor behavior: race and gender differences in willingness to donate blood and cadaveric organs.

BACKGROUND: Recent efforts to recruit blood and organ donors have only marginally improved demographic disparities in willingness to donate. Few studies have examined which factors are most important in explaining race and gender disparities in willingness to donate. OBJECTIVES: To assess race and gender differences in willingness to donate blood and cadaveric organs, and to determine the extent to which several factors (including sociodemographic characteristics and attitudes about religion and mistrust of hospitals) might explain differences in willingness to donate. RESEARCH DESIGN: Cross-sectional telephone survey of Maryland households contacted via random-digit dialing. MEASURES: Past blood donation, organ-donor status on driver's license, and measures of medical mistrust and religious and spiritual salience. SUBJECTS: Persons age 18 to 75 living in the Baltimore, Maryland metropolitan area. RESULTS: Of 385 respondents (84% of randomized households), 114 were black females, 46 were black males, 110 were white females, and 69 were white males. Before adjustment, black females were least willing to donate blood (41%), and black males were least willing to become cadaveric donors (19%) among all race-gender groups. Adjustment for respondent concerns about mistrust of hospitals and discrimination in hospitals explained most differences in willingness to donate blood, whereas adjustment for respondents' beliefs regarding the importance of spirituality and religion explained most differences in willingness to donate cadaveric organs. CONCLUSIONS: Both race and gender are important identifiers of those less willing to donate. To maximize efficiency, donor recruitment efforts should focus on race-gender groups with lowest levels of willingness. Potential donor concerns regarding mistrust in hospitals and religion/spirituality may serve as important issues to address when developing programs to improve donation rates.

Adult↗
PubMedDate not supplied

Race and trust in the health care system.

OBJECTIVE: A legacy of racial discrimination in medical research and the health care system has been linked to a low level of trust in medical research and medical care among African Americans. While racial differences in trust in physicians have been demonstrated, little is known about racial variation in trust of health insurance plans and hospitals. For the present study, the authors analyzed responses to a cross-sectional telephone survey to assess the independent relationship of self-reported race (non-Hispanic black or non-Hispanic white) with trust in physicians, hospitals, and health insurance plans. METHODS: Respondents ages 18-75 years were asked to rate their level of trust in physicians, health insurance plans, and hospitals. Items from the Medical Mistrust Index were used to assess fear and suspicion of hospitals. RESULTS: Responses were analyzed for 49 (42%) non-Hispanic black and 69 (58%) non-Hispanic white respondents (N=118; 94% of total survey population). A majority of respondents trusted physicians (71%) and hospitals (70%), but fewer trusted their health insurance plans (28%). After adjustment for potential confounders, non-Hispanic black respondents were less likely to trust their physicians than non-Hispanic white respondents (adjusted absolute difference 37%; p=0.01) and more likely to trust their health insurance plans (adjusted absolute difference 28%; p=0.04). The difference in trust of hospitals (adjusted absolute difference 13%) was not statistically significant. Non-Hispanic black respondents were more likely than non-Hispanic white respondents to be concerned about personal privacy and the potential for harmful experimentation in hospitals. CONCLUSIONS: Patterns of trust in components of our health care system differ by race. Differences in trust may reflect divergent cultural experiences of blacks and whites as well as differences in expectations for care. Improved understanding of these factors is needed if efforts to enhance patient access to and satisfaction with care are to be effective.

Adult↗
PubMedDate not supplied

Overcoming immunologic incompatibility: transplanting the difficult to transplant patient.

Immunologic incompatibilities between donor and recipient have limited the access to renal transplantation for many patients. Previously the presence of donor-specific alloantibodies directed against donor major histocompatibility complex (MHC) antigens or natural antibodies directed against donor ABO blood group antigens was considered an absolute contraindication to renal transplantation. However, with the current understanding of humoral immune responses, superior immunosuppressive agents, and improved diagnosis and treatment of antibody-mediated rejection, renal transplantation can be safely performed with outstanding results despite the presence of donor-specific antibody. In this review we discuss the biology of antibody-mediated rejection and sensitization. We discuss the diagnostic tests necessary to characterize the type, affinity, and avidity of the donor-directed antibodies. Current methods for performing renal transplants across ABO and human leukocyte antigen (HLA)-sensitized barriers are covered, including the potential morbidities. The rest of the review focuses on advances in managing these antibodies to increase the likelihood of receiving a deceased donor kidney or allow transplantation from a living donor against whom one has a prohibitive antibody.

ABO Blood-Group System↗