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Your search keyword '"A Mandelbrot D"' showing total 39 results
Start Over Author "A Mandelbrot D" Publication Type Academic Journals
39 results on '"A Mandelbrot D"'

33. In kidney transplant recipients with BK polyomavirus infection, early BK nephropathy, microvascular inflammation, and serum creatinine are risk factors for graft loss.

Author

Mohamed, M., Parajuli, S., Muth, B., Astor, B.C., Panzer, S.E., Mandelbrot, D., Zhong, W., and Djamali, A.

Subjects
KIDNEY transplant patients, POLYOMAVIRUS diseases, KIDNEY diseases, CREATININE, BIOPSY, MICROCIRCULATION disorders, INTRAVENOUS immunoglobulins
Abstract

Background Little information is available on the risk factors for graft loss in kidney transplant recipients with BK polyomavirus ( BKPyV) nephropathy ( BKVN) in the presence or absence of antibody-mediated rejection ( AMR). Methods We examined the risk factors for graft loss in consecutive kidney allograft recipients with biopsy-confirmed BKVN, with or without concomitant AMR. Results A total of 1904 kidney transplants were performed at our institution during 2005-2011. Of these, 330 (17.33%) were diagnosed with BKPyV viremia, and 69 were diagnosed with BKVN (3.6%). Eleven patients had a concomitant diagnosis of AMR. Patients with AMR were characterized by significantly higher peak panel-reactive antibody, retransplant rates, and desensitization preconditioning at the time of transplantation, as well as microvascular inflammation ( MVI = glomerulitis + peritubular capillaritis), C4d score, and donor-specific antibody at the time of diagnosis ( P ≤ 0.01). Treatment with plasma exchange, intravenous immunoglobulin, and cidofovir was more prevalent in this group ( P ≤ 0.02). Univariate analyses assessing the risk factors for graft loss in all patients with BKVN, identified an independent association of African-American race, deceased-donor transplantation, serum creatinine (Scr), MVI, and early disease ( BKVN within 6 months of transplant) with poor outcomes. Multivariate analyses retained only 3 variables: Scr >2 mg/dL (hazard ratio [ HR] = 4.3, 95% confidence interval [ CI] 1.9-9.7, P = 0.0004), early BKVN ( HR = 2.7, 95% CI 1.3-5.3, P = 0.004), and MVI ( HR = 1.8, 95% CI 1.2-2.8, P = 0.008). Conclusions These observations suggest that, in patients with BK infection, early BKVN, Scr >2, and MVI are predictors of poor outcomes. Further studies are needed to determine effective treatment strategies for BKVN, with or without AMR. [ABSTRACT FROM AUTHOR]

Published
2016
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39. Evaluation of relative renal function for patients who had undergone simultaneous liver-kidney transplants using Tc-99m-MAG3 scintigraphy with attenuation correction from anatomical images and SPECT/CT.

Author

Palmer MR, Donohoe KJ, Francis JM, and A Mandelbrot D

Subjects
Humans, Kidney diagnostic imaging, Kidney surgery, Photons, Retrospective Studies, Image Processing, Computer-Assisted methods, Kidney physiopathology, Kidney Transplantation diagnostic imaging, Liver Transplantation diagnostic imaging, Technetium Tc 99m Mertiatide, Tomography, Emission-Computed, Single-Photon methods, Tomography, X-Ray Computed methods
Abstract

Objective: Assessing the relative function of each of the three kidneys using nuclear scintigraphy with standard planar imaging in patients having undergone kidney transplant is problematic because of the different photon-attenuation factors associated with native versus transplanted kidneys. To address this, we applied a correction for the attenuation of 140-keV photons based on measurements taken on cross-sectional anatomical images. We performed a validation of the method using single-photon emission computed tomography/computed tomography (SPECT/CT)., Methods: Abdominal CT scans of 13 patients who had undergone simultaneous liver-kidney transplants were examined for kidney depth. Ten of those patients had undergone Tc-99m-mercaptoacetyltriglycine (MAG3) renal scans, using a Philips Precedence SPECT/CT scanner by which abdominal CT and renal SPECT acquisition followed the planar scintigraphic renogram. Kidney depth at the level of the renal hilum was measured on the concurrently acquired CT images, and it was used to derive an attenuation correction factor (ACF) that was applied to the background-subtracted activity in the planar scintigraphic renogram., Results: ACFs calculated from kidney depths ranged from 1.31 to 4.33. The ratio of ACFs for transplant to native kidneys ranged from 0.63 to 1.51, with an average of 0.90. Applying attenuation correction when calculating relative function increased the value of native kidney function by as much as 40%., Conclusion: Attenuation correction through measurements taken on anatomical images, preferably obtained concurrently using a hybrid SPECT/CT scanner, should improve the accuracy of functional measurements in renal scintigraphy. This improved accuracy is clinically important in assessing the relative function of native and transplant kidneys in recipients of simultaneous liver-kidney transplants., (Copyright © 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.)

Published
2011
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