Biomedical subjects

Nauman Siddiqi

Publications and source records attributed to Nauman Siddiqi.

6 recordsLinked to original sources

PubMed2005

Refractory acute kidney transplant rejection with CD20 graft infiltrates and successful therapy with rituximab.

Acute rejection is an expected event after transplantation and has been associated with poor long-term kidney transplant outcome. The presence of B cells in the kidney graft with acute rejection is thought to be an omnious sign, as it has been associated with poor graft outcome. There is no definitive treatment for acute rejection with B cells in the graft. Rituximab, a humanized monoclonal antibody against CD20, has been used in the treatment of B cell lymphoma. We present the case of a 49-yr-old Caucasian male with early acute kidney allograft rejection that was refractory to high doses of steroids and rabbit anti-thymocyte globulin (thymoglobulin). Repeat renal biopsy revealed T cell and B cells in the kidney graft and responded to the combination of rituximab and muromonab (a mouse monoclonal antibody to CD3 receptor). Over 9 months post-transplant, the patient remains rejection free with a serum creatinine of 1.7 mg/dL.

Antibodies, Monoclonal↗

PubMed2005

Clinical risk factors associated with bleeding after native kidney biopsy.

PURPOSE: To determine the effect of various risk factors on postbiopsy bleeding (PBB). PROCEDURE: A retrospective review of 645 native kidney biopsies carried out from 1981 to 2001 was conducted. Data regarding age, gender, race, prebiopsy blood pressure, history of hypertension, pre- and postbiopsy haemoglobin/haematocrit, serum creatinine and blood urea nitrogen (BUN) were collected. FINDINGS: The overall PBB complication rate was 6.2%. High blood pressure was associated with a high risk of bleeding (test for trend, P < 0.05). It increased when systolic blood pressure (SBP) was >160 mm of Hg, diastolic blood pressure (DBP) was >100 mm of Hg, or mean arterial pressure (MAP) was > or = 120 mm of Hg. In patients with a history of hypertension, the risk of PBB was 3.74 times higher (P = 0.0001) than patients with no history of hypertension, irrespective of blood pressure at the time of biopsy. For patients with creatinine > 2 mg/dL, the risk ratio for PBB was 5.89 when compared with patients with creatinine < or = 2 mg/dL. Logistic regression analysis showed that a history of hypertension was associated with PBB, with an odds ratio of 1.89 (confidence interval, 1.10-3.26, P < 0.03), and serum creatinine of > 2.0 mg/dL was associated with an odds ratio of 2.56 (confidence interval, 1.48-4.42, P = 0.001) for PBB. CONCLUSIONS: The risk of PBB increases with high SBP, DBP or MAP. A history of hypertension and high serum creatinine are significant independent risk factors for PBB.

Adult↗

PubMed2004

Similar risk profiles for post-transplant renal dysfunction and long-term graft failure: UNOS/OPTN database analysis.

BACKGROUND: Renal dysfunction measured by serum creatinine (>1.5 mg/dL) at 1 year post-transplant correlates with long-term kidney graft survival. The purpose of this study was to compare the risk factors for elevated serum creatinine (SCr) >1.5 mg/dL at 1 year post-transplantation, and for long-term graft failure. METHODS: Between 1988 and 1999, 117,501 adult kidney transplants were reported to Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS). Of these, 96,091 were functioning at 1 year and SCr was available on 85,135 transplants. Donor and recipient demographics (age, sex, and race), transplant [living vs. cadaveric, previous transplantation, panel reactive antibody (PRA), human leukoocyte antigen (HLA) mismatch, cold ischemic time (CIT) and post-transplant delayed graft function (DGF), use of azathioprone vs. mycophenolate mofetil (MMF), cyclosporine A (CsA) vs. tacrolimus (Tac)], induction antibody, acute rejection within 1 year variables were used in the logistic regression model to estimate odds ratio (OR) for elevated 1 year serum creatinine (SCr). A Cox proportional hazard model was used to estimate the relative risk (RR) for long-term kidney graft failure with and without censoring for death with a functioning graft. RESULTS: Five-year actuarial graft survival for living donor transplant with SCr >1.5 and </=1.5 mg/dL at 1 year post-transplant was 83% and 88.6% (P < 0.001). The corresponding values for cadaveric transplant grafts were 66.5% and 77.9% (P < 0.001). The overall prevalence of renal dysfunction at 1 year post-transplant (SCr >1.5 mg/dL) declined from 54.5% in 1988 to 42.3% in 1999. There was a strong concordance between the key variables, such as cadaveric transplant, increasing CIT, HLA mismatch, DGF, and acute rejection, recipient race (black), younger age, and nondiabetics status; and donor race (black) and older age for elevated SCr and long-term graft failure. CONCLUSION: Donor (age), race (black), recipient race (black), immunologic variables (HLA mismatch, DGF, acute rejection) were identified as important risk factors for elevated SCr at 1 year post-transplantation and long-term graft failure. Elevated SCr should be used as a short-term marker for predicting long-term transplant survival.

Creatinine↗

PubMed2003

Humanized anti-CD20 monoclonal antibody (Rituximab) treatment for post-transplant lymphoproliferative disorder.

INTRODUCTION: Post-transplant lymphoproliferative disorders (PTLD) is a consequence of Epstein-Barr virus (EBV) infection and is a B-cell hyperplasia with CD-20 positive lymphocytes. The treatment of PTLD includes reduction/withdrawal of immunosuppression and chemotherapy. This study reports our center experience with humanized monoclonal antibody against CD-20 (Rituximab) for the treatment of PTLD. MATERIAL AND METHODS: Eight cases of PTLD after solid organ transplantation [six kidney, one kidney/pancreas (KP) and one liver] occurred between September 1998 and October 2001. The mean time between transplant and the diagnosis of PTLD was 57.3 months (range 3 months to 10 yr). Five patients underwent cadaveric transplant, five males and six were Caucasians with mean age of 48 yr (range 20-67 yr). RESULTS: The clinical presentation was as follows: lymphadenopathy--5, gastrointestinal bleeding--2 and tonsillar enlargement--1. The diagnosis was made by a lymph node biopsy in five, a gastric ulcer biopsy in two and a tonsillar biopsy in one case. Six of them had polymorphous, two had monoclonal B-cell lymphoma, and all were positive for CD-20. Six were related to EBV, documented by latent membrane protein (LMP) or Epstein-Barr encoded RNA (EBER) staining. Immunosuppression at the time of PTLD diagnosis consisted of tacrolimus in six cases and cyclosporine A (CsA) in two with mycophenolate mofetil (MMF) and azathioprine--3 each and sirolimus--1. Rituximab was administered at a dose of 375 mg/m2 once a week for 4 wk. There were no side effects seen with this therapy. Immunosuppression was reduced in all patients. Complete remission was observed in seven cases (one required two courses). One patient who did not respond received chemotherapy. Patients were followed for a mean period of 22.5 months (range 10-45 months post-PTLD diagnosis. At the last follow-up all eight patients were alive, seven with a functioning graft and one on maintenance dialysis. Three of these patients had been in remission for more than 2.5 yr. CONCLUSION: Rituximab is an effective agent in the treatment of PTLD without the morbidity characteristic of chemotherapy. Chemotherapy should be reserved only for those refractory to Rituximab therapy.

Adult↗

PubMed2003

Proteinuria: how to evaluate an important finding.

Proteinuria is a common laboratory finding in outpatients and should not be discounted. When it is due to a glomerular disease, early diagnosis is important to prevent further renal damage. Proteinuria may also be a marker for progressive atherosclerosis.

Algorithms↗

PubMed2002

Gender differences in burden and depression among informal caregivers of demented elders in the community.

BACKGROUND: Earlier studies have yielded inconsistent findings regarding gender differences with respect to burden and depression among informal community caregivers of dementia patients. OBJECTIVES: The aim of the study was to determine whether or not there were gender differences in the prevalence of burden and depression among informal caregivers of community-residing dementia patients. METHODS: Data from 259 female and 68 male caregivers who were part of the Canadian Study of Health and Aging were analyzed. Depressive symptoms were measured using the Center for Epidemiologic Studies--Depression Scale (CES-D). Burden was assessed using Zarit's Burden Interview. Associations between the outcome variables (depressive symtoms and burden) and the independent variable, gender, were examined using logistic regression. RESULTS: In multivariable analysis, female caregivers were found to have significantly higher odds than male caregivers of having a score of 33 or higher on Zarit's Burden Interview (OR=2.6; 95% CI 1.0, 6.7). The OR comparing women to men with respect to a high level of depressive symptoms (defined as a score of 16 or more on the CES-D) was not significant (OR=1.3; 95% CI 0.6, 2.9). Poor perceived caregivers health and more behavior disturbance in the patient were associated with significantly higher odds of high levels of caregiver burden and depression. CONCLUSIONS: Adequate assistance must be given to women caregivers to ensure that they are not strained beyond what is clinically healthy. In addition, interventions should target caregivers of behaviorally disturbed patients as well as caregivers who report poor physical health to reduce the negative psychological impact of caregiving.

Adult↗