Search PubMed⌕ Search

Biomedical subjects

G M Danovitch

Publications and source records attributed to G M Danovitch.

At least 19 recordsLinked to original sources
PubMed2006

Limiting financial disincentives in live organ donation: a rational solution to the kidney shortage.

Availability of kidney transplantation is limited by an inadequate supply of organs, with no apparent remedy on the immediate horizon and increasing reliance on living donors (LDs). While some have advocated financial remuneration to stimulate donation, the National Organ Transplant Act (NOTA) of 1984 expressly forbids the offer of 'valuable consideration.' However, recent developments indicate some fluidity in the definition of valuable consideration while evolving international standards highlight deficiencies (particularly regarding long-term care and follow-up) in the current American system. Recognizing that substantial financial and physical disincentives exist for LDs, we propose a policy change that offers the potential to enhance organ availability as well as address concerns regarding long-term care. Donors assume much greater risk than is widely acknowledged, risk that can be approximated for the purpose of determining appropriate compensation. Our proposal offsets donor risk via a package of specific benefits (life insurance, health insurance and a small amount of cash) to minimize hazard and ensure donor interests are protected after as well as before nephrectomy. It will fund medical follow-up and enable data collection so that long-term risk can be accurately assessed. The proposal should be cost effective with only a small increase in the number of LDs, and the net benefit will become greater if removal of disincentives stimulates even further growth. As importantly, by directly linking compensation to risk, we believe it preserves the essence of kidney donation as a gift, consistent with NOTA and implementable in the United States without altering current legal statutes.

Costs and Cost Analysis↗
PubMed2006

Obesity and outcome following renal transplantation.

Single institution series have demonstrated that obese patients have higher rates of wound infection and delayed graft function (DGF), but similar rates of graft survival. We used UNOS data to determine whether obesity affects outcome following renal transplantation. From the UNOS database, we identified patients who underwent primary kidney-only transplantation between 1997 and 1999. Recipient and donor body mass index (BMI) was categorized as underweight (BMI < 18.5), normal (BMI 18.5-24.9), overweight (BMI 25-29.9), obese (BMI 30-34.9) or morbidly obese (BMI > or = 35). We correlated BMI with intermediate measures of graft outcome and overall graft survival, and created multivariate models to evaluate the independent effect of BMI on graft outcome, adjusting for factors known to affect graft success. The study sample comprised 27,377 recipients. Older age, female sex, African American race and increased comorbidity were associated with obesity (p < 0.001). Compared with normal weight patients, morbid obesity was independently associated with an increased risk of DGF (p < 0.001), prolonged hospitalization (p < 0.001), acute rejection (p = 0.006) and decreased overall graft survival (p = 0.001). Donor BMI did not affect overall graft survival (p > or = 0.07). Recipient obesity is associated with an increased risk of DGF and decreased graft survival following renal transplantation.

Adult↗
PubMed2001

Cyclosporine microemulsion- and mycophenolate mofetil-related lymphoid aggregates are not associated with acute rejection.

BACKGROUND: Microemulsion cyclosporine, mycophenolate mofetil, and prednisone have become a common immunosuppressive protocol in renal transplantation. We identified lymphocytic infiltrates in transplant fine-needle aspirates and core biopsies from patients on this regimen without acute rejection clinically or by standardized morphological criteria and investigated this inflammatory response. METHODS: Twenty-eight aspirates from 21 patients were included and assessed in the standard fashion. Nine core biopsies showing interstitial lymphocytic infiltration were evaluated with antibodies against CD3, CD4, CD8, CD20, CD30, CD56, KP1, and epithelial membrane antigen (EMA). Aspirates and biopsies were assessed for tubular cell major histocompatibility complex (MHC) class II antigen and for gamma-interferon (gamma-IFN), interleukin-4 (IL-4), and IL-10 mRNAs by reverse transcription-polymerase chain reaction. RESULTS: Fifteen aspirates showed immune activation solely due to mature lymphocytes and monocytes; 13 had no immune activation. All aspirates were negative for MHC class II antigens. Of 6 activated aspirates assessed for gamma-IFN mRNA, 5 were negative. All 21 patients had similar clinical characteristics and recovered renal function without rejection treatment. The core biopsies had lymphocytes in 5-30% of the interstitium. The cells were 70-85% CD3+, with 50-85% CD4+, 3-10% KP1+, and rare cells CD56+. No T-cell activation was present (EMA- and CD30-). Seven biopsies were assessed and were negative for gamma-IFN mRNA; only one biopsy had weakly positive MHC class II staining. Two activated aspirates were negative for IL-4 and IL-10 mRNA, while three biopsies each contained IL-4 and IL-10 mRNAs. CONCLUSIONS: Inactive interstitial lymphoid infiltrates are frequent in patients on this drug regimen and should not be interpreted as acute rejection, particularly in aspirate samples. These lymphocytes may play a role in long-term allograft acceptance.

Antigens, CD↗
PubMed2000

Cyclosporine and tacrolimus-associated thrombotic microangiopathy.

The development of thrombotic microangiopathy (TMA) associated with the use of cyclosporine has been well documented. Treatments have included discontinuation or reduction of cyclosporine dose with or without concurrent plasma exchange, plasma infusion, anticoagulation, and intravenous immunoglobulin G infusion. However, for recipients of organ transplantation, removing the inciting agent is not without the attendant risk of precipitating acute rejection and graft loss. The last decade has seen the emergence of tacrolimus as a potent immunosuppressive agent with mechanisms of action virtually identical to those of cyclosporine. As a result, switching to tacrolimus has been reported to be a viable therapeutic option in the setting of cyclosporine-induced TMA. With the more widespread application of tacrolimus in organ transplantation, tacrolimus-associated TMA has also been recognized. However, literature regarding the incidence of the recurrence of TMA in patients exposed sequentially to cyclosporine and tacrolimus is limited. We report a case of a living donor renal transplant recipient who developed cyclosporine-induced TMA that responded to the withdrawal of cyclosporine in conjunction with plasmapheresis and fresh frozen plasma replacement therapy. Introduction of tacrolimus as an alternative immunosuppressive agent resulted in the recurrence of TMA and the subsequent loss of the renal allograft. Patients who are switched from cyclosporine to tacrolimus or vice versa should be closely monitored for the signs and symptoms of recurrent TMA.

Adult↗
PubMed2000

Recommendations for the outpatient surveillance of renal transplant recipients. American Society of Transplantation.

Many complications after renal transplantation can be prevented if they are detected early. Guidelines have been developed for the prevention of diseases in the general population, but there are no comprehensive guidelines for the prevention of diseases and complications after renal transplantation. Therefore, the Clinical Practice Guidelines Committee of the American Society of Transplantation developed these guidelines to help physicians and other health care workers provide optimal care for renal transplant recipients. The guidelines are also intended to indirectly help patients receive the access to care that they need to ensure long-term allograft survival, by attempting to systematically define what that care encompasses. The guidelines are applicable to all adult and pediatric renal transplant recipients, and they cover the outpatient screening for and prevention of diseases and complications that commonly occur after renal transplantation. They do not cover the diagnosis and treatment of diseases and complications after they become manifest, and they do not cover the pretransplant evaluation of renal transplant candidates. The guidelines are comprehensive, but they do not pretend to cover every aspect of care. As much as possible, the guidelines are evidence-based, and each recommendation has been given a subjective grade to indicate the strength of evidence that supports the recommendation. It is hoped that these guidelines will provide a framework for additional discussion and research that will improve the care of renal transplant recipients.

Ambulatory Care↗
PubMed1999

Unequal access to cadaveric kidney transplantation in California based on insurance status.

OBJECTIVE: To assess the impact of insurance status on access to kidney transplantation among California dialysis patients. STUDY SETTING: California Medicare and Medicaid dialysis populations. STUDY DESIGN: All California ESRD dialysis patients under age 65 eligible for Medicare or Medicaid in 1991 (n = 9,102) took part in this cohort analytic study. DATA COLLECTION: Medicare and California Medicaid Program data were matched to the Organ Procurement and Transplantation Network Kidney Wait List files. PRINCIPAL FINDINGS: Only 31.4 percent of California Medicaid dialysis patients were placed on the kidney transplant waiting list compared to 38.8 percent and 45.0 percent of dually eligible Medicate/Medicaid and Medicare patients, respectively. Compared to the Medicaid population, Medicare enrollees were more likely to be placed on the kidney transplant waiting list (adjusted Relative Risk [RR] = 2.10, Confidence Interval [CI] 1.68, 2.62) as were dually eligible patients (RR = 1.54, CI 1.24, 1.91). Once on the waiting list, however, Medicare enrollment did not influence the adjusted median waiting time to acquire a first cadaveric transplant (p > .05). CONCLUSIONS: California dialysis patients excluded from Medicare coverage, who are disproportionately minority, female, and poor, are much less likely to enter the U.S. transplant system. We hypothesize that patient concerns with potential subsequent loss of insurance coverage as well as cultural and educational barriers are possible explanatory factors. Once in the system, however, insurance status does not influence receipt of a cadaveric renal transplant.

Adolescent↗
PubMed1997

Helical CT angiography for examination of living renal donors.

OBJECTIVE: This prospective study was intended to determine if helical CT arteriography plus conventional radiography is sufficiently accurate to replace and less costly than excretory urography and conventional renal arteriography, the techniques currently used to examine living renal donors. SUBJECTS AND METHODS: Patients underwent CT arteriography with a helical CT scanner. Conventional radiographs were obtained during the pyelographic phase to evaluate the urothelium. Findings on CT arteriograms were compared with findings on conventional arteriograms and at surgery. RESULTS: Of 57 patients who underwent CT arteriography, 46 also underwent conventional arteriography and 40 underwent surgery. For those 46 patients, we found agreement between results of CT arteriography and conventional arteriography in 89% of kidneys. For those 40 patients, we found agreement between results of CT arteriography and findings at surgery in 90% of kidneys and agreement between results of conventional arteriography and findings at surgery in 87% of kidneys. Of the 57 patients, six (11%) had findings on CT angiograms that precluded further consideration for donation. CONCLUSION: Eight to ten percent of renal arteries are not seen on renal arteriograms when compared with findings at surgery. Our results indicate that CT arteriography is as accurate as conventional arteriography at revealing the number of vessels that perfuse and drain the kidneys and can replace conventional arteriography. Use of CT angiography plus conventional radiography instead of excretory urography and conventional arteriography can result in a 35-50% reduction in cost of the imaging studies in potential renal donors.

Adult↗
PubMed1996

A multicenter trial of FK506 (tacrolimus) therapy in refractory acute renal allograft rejection. A report of the Tacrolimus Kidney Transplantation Rescue Study Group.

A multicenter trial was conducted to evaluate the efficacy and safety of tacrolimus in the treatment of refractory renal allograft rejection. Renal transplant recipients experiencing biopsy-proven recurrent acute allograft rejection were eligible if the current rejection episode was refractory to corticosteroids. A total of 73 patients were enrolled, of whom 59 (81%) had previously received at least one course of antilymphocyte antibody as rejection therapy. One-year follow-up was available in 93% of patients. Median time to tacrolimus rescue therapy was 75 days after transplantation (range, 18-1448 days). Therapeutic responses to tacrolimus included improvement in 78% of patients, stabilization in 11%, and progressive deterioration in 11%. The risk of experiencing progressive deterioration was related to the pretacrolimus serum creatinine level: serum creatinine < or = mg/dl, 3%; 3.1-5 mg/dl, 16% (P < 0.04); > 5 mg/dl, 23% (P < 0.02). Twelve-month (from the time of initiation of tacrolimus therapy) actuarial patient and graft survival rates were 93% and 75%. Graft loss occurred in 19 patients (25%) at a median time of 108 days. Fourteen episodes of recurrent rejection were diagnosed in 10 patients (14%), at a median time of 101 days. Eleven episodes of recurrent rejection were treated (three patients underwent transplant nephrectomy), with resolution achieved in nine patients. Antilymphocyte antibody therapy was not used to treat recurrent rejection. Serum creatinine values improved during tacrolimus therapy: median serum creatinine level before tacrolimus, 3.2 mg/dl; median at 1 year after tacrolimus, 1.8 mg/dl. Twelve infections were documented in 11 patients (15%), including cytomegalovirus infection in three patients (4%). Posttransplant lymphoproliferative disorder was diagnosed in a single patient. Tacrolimus whole blood levels averaged 15.0 +/- 9.9 ng/ml at day 7 of tacrolimus therapy and 9.4 +/- 5.1 ng/ml at 1 year, and were consistent among individual centers. Treatment outcome did not correlate with tacrolimus blood levels. The most commonly observed adverse events were neurological and gastrointestinal. Seventy-four percent of patients received tacrolimus for at least 1 year. Tacrolimus therapy was discontinued in 18% of patients for rejection (11% for progressive, unrelenting rejection, and 7% for recurrent rejection). Tacrolimus therapy was discontinued in 8% of patients due to adverse events. In conclusion, tacrolimus rescue therapy provides (1) prompt, effective reversal of refractory renal allograft rejection, (2) good long-term renal allograft function, (3) a low incidence of recurrent rejection, and (4) an acceptable safety profile in renal allograft recipients experiencing refractory rejection.

Acute Disease↗
PubMed1996

Pentoxifylline does not prevent the cytokine-induced first dose reaction following OKT3--a randomized, double-blind placebo-controlled study.

The use of OKT3 as an immunosuppressive agent is accompanied by increased cytokine production and constellation of side effects collectively termed cytokine release syndrome (CRS). Pentoxifylline (PTF) inhibits synthesis of some cytokines, and has been shown to attenuate CRS when administered before OKT3. In this double-blinded, placebo-controlled study, 46 renal allograft recipients were randomized to receive either PTF (800 mg q 8 hr for at least 24 h) p.o. or placebo, along with methylprednisolone (7 mg/kg), diphenhydramine, and acetaminophen, prior to beginning OKT3 as therapy for acute rejection. Patients were observed, and symptoms scored semiquantitatively. Despite the presence of therapeutic PTF levels (721 +/- 726 ng/ml), the frequency and severity of side effects (fever, chills, headache, neurocortical symptoms, dyspnea, nausea, vomiting, diarrhea) did not differ between treatment groups. Likewise PTF did not affect renal function or immunologic response to OKT3, with similar graft and patient survival in both groups. Plasma levels of TNF alpha, IFN gamma, IL-6, and IL-8 increased as predicted following OKT3 administration, without significant differences between PTF and placebo groups. In this controlled, multicenter trial, pretreatment with oral PTF was ineffective in attenuating OKT3-related CRS in renal allograft recipients.

Adult↗