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Stephen R Smith

Publications and source records attributed to Stephen R Smith.

At least 19 recordsLinked to original sources
PubMed2006

Automated external defibrillators and survival from cardiac arrest in the outpatient hemodialysis clinic.

Automated external defibrillators (AED) have been recommended for use in outpatient dialysis clinics to improve outcomes from cardiac arrest, the most common cause of death in patients with ESRD. The effectiveness of this policy is unknown. The study cohort consisted of 43,200 hemodialysis patients in the US Gambro Healthcare System from 2002 to 2005. Of these, 729 patients who sustained an in-center cardiac arrest were identified. Baseline characteristics at the time of the event were compared between patients who underwent hemodialysis in clinics with and without an AED on site. Unadjusted survival and survival adjusted for potential confounders was measured using Cox proportional hazards regression models. Unadjusted survival at 30 d was 19 versus 15% (P = 0.12) and 9.5 versus 7.8% at 1 yr (P = 0.39) in the AED-present and AED-absent groups, respectively. AED presence was not associated with outcome in unadjusted analysis (hazard ratio [HR] 0.91; 95% confidence interval [CI] 0.78 to 1.07; P = 0.26). Univariable analysis identified age (HR 1.07 per decade; 95% CI 1.01 to 1.13), serum albumin (HR 0.91 per 0.7-mg/dl increase; 95% CI 0.82 to 1.01), and indwelling dialysis catheters (HR 1.21; 95% CI 1.02 to 1.42) as potential confounders. Medications including angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, beta blockers, calcium channel blockers, other BP medications, aspirin, antibiotics, and antiarrhythmics were associated with survival and considered confounders. After controlling for case mix and confounders, AED presence was not associated with outcome (HR 0.98; 95% CI 0.82 to 1.18; P = 0.83). Presence of AED in the dialysis clinic is not sufficient by itself to improve the abysmal outcome from in-clinic cardiac arrest in hemodialysis patients in the United States.

Aged↗
PubMed2006

Postinfectious glomerulonephritis in renal allograft recipients.

Postinfectious glomerulonephritis (PIGN) is a rare etiology of de novo glomerulonephritis following kidney transplantation. To date, there have only been eight cases reported in the literature. We report an additional three patients transplanted at our institution between January 2000 and October 2004 who had clinical and pathologic findings consistent with posttransplant PIGN. All three patients were type 1 diabetics. One had received a cadaveric kidney transplant, one a simultaneous kidney-pancreas transplant, and the third a living related kidney transplant followed by a pancreas transplant. All patients were on triple immunosuppressive therapy with tacrolimus, mycophenolate mofetil, and prednisone. In each case, an acute decline in allograft function developed in association with a known or suspected infectious process, and renal biopsies revealed an immune complex glomerulonephritis with features of PIGN. All regained renal function with treatment of their known or suspected infections and without specific therapies for their glomerulonephritis, including corticosteroids.

Adult↗
PubMed2005

Intravenous immunoglobulin and plasmapheresis in acute humoral rejection: experience in renal allograft transplantation.

Acute humoral rejection (AHR) in kidney transplantation is associated with higher rates of allograft loss when compared with acute cellular rejection (ACR). Treatment with intravenous immunoglobulin (IVIG) combined with plasmapheresis (PP) has been used recently in many centers. We report the incidence, clinical characteristics, and outcome of patients with AHR treated with IVIG and PP. All patients (n=519) at our institution who underwent kidney transplantation between January 1999 and August 2003 were retrospectively analyzed and classified according to biopsy results into three groups: AHR, ACR, and no rejection. AHR was diagnosed in 23 patients (4.5%) and ACR in 75 patients (15%). Mean follow-up was 844+/-23 days. Female sex, black race, and high panel-reactive antibody were risk factors for AHR. Most AHR patients (22 of 23) were treated with IVIG and PP. Two-year graft survival was numerically worse in patients with AHR versus ACR (78% vs. 85%, p=0.5) but the difference was not statistically significant. Graft survival after AHR treated with IVIG and PP is much better than it has been historically. IVIG in combination with PP is an effective treatment for AHR. Graft survival in this setting is similar to graft survival in patients with ACR.

Acute Disease↗
PubMed2005

Acute renal failure after lung transplantation: incidence, predictors and impact on perioperative morbidity and mortality.

The incidence, predictors and clinical significance of acute renal failure (ARF) after lung transplantation are not well described. We retrospectively collected data on 296 patients transplanted at our center between April 1992 and December 2000; follow-up was extended until December 2002. Patients were initially divided into two groups: ARF (doubling of baseline creatinine within 2 weeks after surgery) and NoARF. The ARF group was subdivided into ARFD (dialyzed) and ARFnD (not dialyzed). The incidence of ARF was 56% (166/296), but most cases were ARFnD (n = 143). Independent predictors of ARFD (n = 23) were: baseline GFR (OR 0.98, CI 0.96-0.99, p = 0.012), pulmonary diagnosis other than COPD (OR 6.80, CI 1.5-30.89, p = 0.013), mechanical ventilation > 1 d (OR 6.16, CI 1.70-22.24, p = 0.006) and parenteral amphotericin B use (OR 3.04, CI 1.03-8.98, p = 0.045). Both ARFnD and ARFD were associated with longer duration of mechanical ventilation, increased hospital stay and increased early mortality. One-year patient survival was 92.3%, 81.8% and 21.7% in the NoARF, ARFnD and ARFD groups, respectively (p < 0.0001). After controlling for important covariates, ARFD remained associated with an increased hazard of dying (HR 6.77, CI 4.00-11.44, p < 0.0001). In conclusion, ARF occurs commonly after lung transplantation and affects important clinical outcomes, especially when dialysis is required.

Acute Kidney Injury↗
PubMed2004

Massive gastrointestinal hemorrhage due to rupture of a donor pancreatic artery pseudoaneurysm in a pancreas transplant patient.

Enteric drainage of secretions by anastomosing the donor duodenum to the recipient's small bowel has become common in pancreatic transplantation. While it eliminates many problems, endoscopic access to the transplanted duodenum and pancreas is made difficult. After a pancreas kidney transplant, the patient presented with massive hematochezia. Upper and lower endoscopy revealed large amounts of red blood in the colon but no specific bleeding site. Mesenteric angiography was normal but pelvic angiography showed rapid extravasation of contrast from a pseudoaneurysm of the pancreatic transplant artery. This was successfully embolized with coils. To the best of our knowledge, this is the first case of massive gastrointestinal hemorrhage because of rupture of a pseudoaneurysm of the donor pancreatic artery in a pancreas transplant patient. We report this case and review our institution's experience with all forms of gastrointestinal bleeding in pancreas transplant patients.

Aneurysm, False↗
PubMed2004

Risk factors for BK polyomavirus nephritis in renal allograft recipients.

Recurrent episodes of acute rejection (AR) and/or the intense immunosuppression used for their treatment have been proposed as risk factors for BK nephritis (BKN; BK refers to the initials of the first patient from whom this polyomavirus was isolated). To further examine the relationship between AR and BKN, we analyzed all kidney transplants performed at our center between January 1999 and August 2001 (n = 286). After a mean follow-up of 737 +/- 22 d, we identified nine cases of BKN (3.1%). The mean time to diagnosis of BKN was 326 +/- 56 d. No patient with BKN had a prior history of AR. During the same period, 62 patients were diagnosed with AR (22%). The mean time to diagnosis of AR was 197 +/- 40 d (p = 0.01 vs. time to diagnosis of BKN). Despite aggressive therapy with methylprednisolone and, in some cases, anti-lymphocyte antibody, none of these patients with AR developed BKN. We compared the baseline characteristics of patients in both groups and found that BKN patients were more likely to be white people (78 vs. 44%, p = 0.05) and male (89 vs. 53%, p = 0.04). Moreover, the mean tacrolimus (TAC) levels before diagnosis were higher in BKN than in AR patients (11.7 +/- 0.5 vs. 6.5 +/- 0.6 ng/mL, p < 0.001). In summary, our study shows that BKN often occurs in the absence of prior episodes of AR. In addition, our findings suggest that white males exposed to higher TAC levels are at greater risk of developing BKN.

Adult↗
PubMed2003

Beneficial effect of plasmapheresis and intravenous immunoglobulin on renal allograft survival of patients with acute humoral rejection.

BACKGROUND: Acute humoral rejection (AHR) has been associated with enhanced graft loss. Our study compared the renal allograft survival of patients with AHR treated with plasmapheresis (PP) and intravenous immunoglobulin (IVIG) with allograft survival in patients with acute cellular rejection (ACR). METHODS: We retrospectively analyzed all kidney transplants performed at our institution between January 1999 and August 2001 (n=286). Recipients were classified into three groups according to biopsy reports: AHR, ACR, or no rejection. The ACR group was further divided into early and late rejection (<90 and >90 days posttransplant, respectively). RESULTS: After a mean follow-up of 569+/-19 days, the incidence of AHR was 5.6% (n=16). Recipient presensitization, delayed graft function, early rejection, and higher creatinine at diagnosis were characteristic of AHR. Most AHR patients (14/16) were treated with PP and IVIG. One patient received only IVIG, whereas another received only PP. All AHR patients were given steroid pulses, but only four received antilymphocyte therapy because of concomitant severe ACR. The ACR group comprised 43 patients (15%). One patient with mild rejection received no therapy, 20 improved with steroids alone, and 22 required additional antilymphocyte therapy. One-year graft survival by Kaplan Meier analysis was 81% and 84% in the AHR and ACR groups, respectively (P=NS). Outcomes remained similar when AHR patients were compared with those with early ACR. CONCLUSIONS: We conclude that AHR, when diagnosed early and treated aggressively with PP and IVIG, carries a short-term prognosis that is similar to ACR.

Acute Disease↗
PubMed2003

Post transplant erythrocytosis in hypercalcemic renal transplant recipients.

In vitro data suggest that calcium plays an important role in normal and disordered erythropoiesis. The purpose of this study is to determine whether there is an association between serum calcium, various hormone levels, and the development of post transplant erythrocytosis (PTE). Data were collected on 283 patients who underwent renal transplantation between 1994 and 1998. The relationship between serum calcium and PTE development was tested using the chi-square test. Univariate and multivariable adjusted models were employed to determine predictors of maximum hematocrit. Selected patients underwent measurement of intact parathyroid hormone (PTH), 1,25-dihydroxy vitamin D, and erythropoietin (EPO). Seventy-three patients (26%) developed PTE. Post transplant erythrocytosis was more common in patients with hypercalcemia compared with patients with normal serum calcium (34% vs. 18%, p = 0.002). In multivariable analyses, serum calcium was a strong independent predictor of maximum hematocrit post transplant, even after adjustment for renal function. A serum calcium of >or=10.2 mg/dL was associated with greater than two-fold increased odds of PTE. There were no differences in hormone levels between subjects with hypercalcemia and PTE, subjects with PTE alone, and subjects with hypercalcemia alone. Hypercalcemia is associated with the development of PTE in renal transplant recipients.

Adult↗
PubMed2003

Assessing students' performances in a competency-based curriculum.

Brown Medical School embarked on planning a competency-based curriculum in 1989. The curriculum was fully implemented in 1996, effective for the MD class of 2000. To graduate, a student must (1) demonstrate mastery of the medical knowledge base, (2) achieve beginning and intermediate levels of proficiency in nine key abilities, and (3) attain an advanced level in the ability called "problem solving" and three other abilities that the student chooses based on his or her interests. The nine abilities are effective communication; basic clinical skills; using basic science in the practice of medicine; diagnosis, management, and prevention; lifelong learning; self-awareness, self-care, and personal growth; the social and community contexts of health care; moral reasoning and clinical ethics; and problem solving. As a major educational innovation, the new competency-based curriculum has been successfully woven into the fabric of the medical school learning environment. In this article, the authors describe how faculty go about assessing students' performances relative to the nine abilities.

Academic Medical Centers↗
PubMed2002

Declining influence of race on the outcome of living-donor renal transplantation.

A racial disparity in graft survival for renal transplant recipients has been documented for both cadaveric and living-donor transplants. In the present single-center study we analyzed graft survival by race for recipients of living-donor kidney transplants in three eras: 1985-89, 1990-94, and 1995-2000. There was an intensification of the immunosuppressant regimen beginning in 1996, such that all patients received cyclosporine or tacrolimus with mycophenolate and prednisone. Graft survival was analyzed using the Cox proportional hazards model. There were 79 black recipients and 210 white recipients with no difference in mean age, degree of HLA matching, or proportion of recipients with diabetes as the cause of end-stage renal disease. Using all data from 1985 to 2000, graft survival was significantly better for whites vs. blacks adjusted for age, gender, diabetes, era of the transplant, and haplotype match (p = 0.05). However, when analyzed by era, there was a temporal trend for a progressive decrease in the racial disparity in graft survival. In confirmation of this effect, there was a significant race-era interaction (p = 0.01) on multivariable Cox proportional hazards analysis. The most recent data from the United States Renal Data System (USRDS) show a similar decrease in the racial difference in 1-year graft survival. We conclude that the influence of race on living-donor graft survival is diminishing over time.

Adult↗