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Dive into the research topics where Ronald D. Guttmann is active.

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Featured researches published by Ronald D. Guttmann.


Transplantation | 1995

Impact of renal transplantation on uremic cardiomyopathy

Patrick S. Parfrey; John D. Harnett; Robert N. Foley; Gloria M. Kent; David C. Murray; Paul E. Barre; Ronald D. Guttmann

In chronic uremia, cardiomyopathy manifests itself as systolic dysfunction, concentric left ventricular (LV) hypertrophy, or LV dilatation. To determine the impact of renal transplantation on uremic cardiomyopathy, all dialysis patients participating in a long-term cohort study who received a successful renal transplant were followed with echocardiography. The transplanted group comprised 102 of 433 (24%) endstage renal disease (ESRD) patients. They were significantly younger and, on starting ESRD therapy, had significantly less ischemic heart disease and cardiac failure than the overall ESRD cohort. During followup, ischemic heart disease developed in only 1 patient and none experienced cardiac failure. In the 12% (n = 12) of patients with systolic dysfunction before renal transplant, fractional shortening normalized in all patients, increasing from 21.5 +/- 4.6% to 33.5 +/- 5.6% after transplantation. In the 41% (n = 41) with concentric LV hypertrophy before transplantation, the LV mass index improved from 158 +/- 39 g/m2 to 132 +/- 39 g/m2. LV dilatation was present in 32% (n = 32) of patients before transplantation. After transplantation, LV volume fell from 116 +/- 3.1 ml/m2 to 89 +/- 21 ml/m2, and LV mass index in this group fell from 166 +/- 55 g/m2 to 135 +/- 37 g/m2. It was not possible to associate risk factors characteristic of the uremic state with the improvement in cardiac structure and function, although the fall in LV mass was significantly associated with fall in blood pressure. We conclude that correction of the uremic state by renal transplantation leads to normalization of LV contractility in systolic dysfunction, regression of hypertrophy in concentric LV hypertrophy, and improvement of cavity volume in LV dilatation. The degree of improvement suggests that dialysis patients with uremic cardiomyopathy would benefit from renal transplantation.


Nephron | 1988

Left Ventricular Hypertrophy in End-Stage Renal Disease

John D. Harnett; Patrick S. Parfrey; Sheila M. Griffiths; M.H. Gault; Paul E. Barre; Ronald D. Guttmann

To determine the prevalence of left ventricular hypertrophy (LVH; left ventricular wall thickness greater than or equal to 1-2 cm in diastole) among end-stage renal disease (ESRD) patients and the most important risk factors that independently relate to LVH, 189 non-diabetic ESRD patients without dilated cardiomyopathy in two centres had echocardiography and full clinical review. 104 of 189 (55%) patients had LVH consisting of 52 of 83 (65%) patients on haemodialysis, 18 of 20 (90%) peritoneal dialysis patients and 34 of 86 (40%) transplanted patients. Using multiple logistic regression, the most important factors which independently related to LVH, in all patients studied, were dialysis as current ESRD treatment (p less than 0.001), followed by age (p = 0.008), hypertension as defined by number of blood pressure medications (p = 0.007), followed by high serum alkaline phosphatase which probably reflects hyperparathyroidism (p = 0.03). In a subset of patients with severe LVH (left ventricular wall thickness greater than or equal to 1.4 cm), a high serum alkaline phosphatase level was the best predictor of LVH (p less than 0.001), followed by high diastolic blood pressure (p = 0.004) and age (p = 0.02). In dialysis patients, the most important variable were age (p = 0.009) and high serum alkaline phosphatase (p = 0.03). In the transplant group, patients with LVH were taking significantly more antihypertensive medications than those without LVH (p = 0.002). This variable was the only predictor of LVH in the transplant group.(ABSTRACT TRUNCATED AT 250 WORDS)


Transplantation | 1985

The impact of renal transplantation on the course of hepatitis B liver disease

P. S. Parfrey; R. D. C. Forbes; T. A. Hutchinson; S. Kenick; D. Farge; W. D. Dauphinee; J. F. Seely; Ronald D. Guttmann

To establish the impact of transplantation on the course of chronic hepatitis B liver disease we performed a prospective study of the clinical and pathological sequelae of hepatitis B disease in all 22 patients who had renal allografts that functioned for more than 1 year and who were hepatitis B surface antigen (HB Ag)-positive following transplantation. No patient converted to HB Ag-negative. During a mean follow-up of 83 months serial liver biopsies were performed in 20 patients and 1 liver biopsy was available in the remaining 2 patients. Eleven patients died of liver disease, 5 of whom died of hepatic failure, 3 with hepatoma, 2 of gastrointestinal hemorrhage, and 1 of ascites with pleuroperitoneal fistula. Aggressive liver disease was observed in the vast majority of patients: 12 ultimately developed cirrhosis, (mean follow-up 81 months), 6 chronic active hepatitis (mean follow-up 93 months), 3 chronic persistent hepatitis (mean follow-up 93 months), 3 chronic persistent hepatitis (mean follow-up 89 months), and in 1 patient the presence of HB virus in hepatocytes was the sole morphologic alteration (follow-up 42 months). There was a marked tendency to progression in that 82% of patients with virus only, reactive hepatitis, or chronic persistent hepatitis on initial biopsy subsequently developed chronic active hepatitis of cirrhosis. For comparison, 10 HB Ag-positive patients whose renal failure had been treated by hemodialysis were also studied over a comparable period. Four patients converted to the negative state. Biochemical evidence of persistent liver dysfunction occurred in only 1 patient and no patient has died from complications of liver disease. We conclude that in the immunosuppressed renal transplant patient HB infection often results in the development of cirrhosis, leading to death from hepatoma and hepatic failure. This course is worse than that in dialysis patients. Renal transplantation of HB Ag-positive patients with end-stage renal failure may be inadvisable.


Transplantation | 2000

Long-term changes in left ventricular hypertrophy after renal transplantation.

Claudio Rigatto; Robert N. Foley; Gloria M. Kent; Ronald D. Guttmann; Patrick S. Parfrey

Background. Concentric and eccentric left ventricular hypertrophy are common progressive disorders in dialysis patients and are associated with cardiac failure and death. Although partial regression of these abnormalities is known to occur during the first posttransplant year, their long-term evolution is unknown. Methods. A total of 143 of 433 dialysis patients participating in a long-term prospective cohort study received renal transplants. Laboratory parameters were assessed monthly. Echocardiography was performed annually. Left ventricular mass index (LVMI) and cavity volume index were calculated according to standard formulae. Multiple linear regression was used to model change in LVMI as a function of baseline clinical and laboratory variables. Results. LVMI fell from 161 g/m2 at 1 year to 146 g/m2 (P =0.009) g/m2 after 2 years. No further regression was seen in years 3 and 4. Left ventricular volume index showed similar trends, with a decline from year 1 to year 2 (P =0.05) followed by stabilization in years 3 and 4. Older age, long duration of hypertension, need for more than one antihypertensive, high pulse pressure in normal-size hearts, and low pulse pressure in dilated hearts were significantly associated with failure of regression of LVMI between the first and second years (MLR, P <0.000001, r2=0.57). Conclusions. Regression of left ventricular hypertrophy continues beyond the first year after renal transplantation, reaching a nadir at 2 years and persisting into the third and fourth posttransplant years. Failure to regress was associated with older age, hypertension, high pulse pressure in normal-size hearts and low pulse pressure in dilated hearts.


Journal of Nervous and Mental Disease | 1993

Live and Learn: Patient Education Delays the Need to Initiate Renal Replacement Therapy in End-stage Renal Disease

Yitzchak M. Binik; Gerald M. Devins; Paul E. Barre; Ronald D. Guttmann; David J. Hollomby; Henry Mandin; Leendert C. Paul; Ronald B. Hons; Ellen Burgess

During a longitudinal study of the quality of life of end-stage renal disease, 204 patients with deteriorating renal function were identified before dialysis or transplantation was required to preserve their lives. These patients were randomly assigned to either an enhanced or a standard education condition. The enhanced education condition consisted of a specially prepared slide-lecture show concerning kidney diseases and their treatment that was delivered by a trained research assistant. The standard education condition consisted of whatever educational procedures were routinely available at the participating hospital. All but six patients have now started treatment by maintenance dialysis. Individuals in the enhanced education condition survived an average of 4.6 months longer than did those in the standard education group without requiring the initiation of renal replacement therapy. This effect could not be attributed to physical differences between the groups, to cohort effects, to delays in contacting the patients, or to when or where they were identified. Possible mechanisms for this effect are discussed.


Transplantation | 1984

The Clinical And Pathological Course Of Hepatitis B Liver Disease In Renal Transplant Recipients

P. S. Parfrey; R. D. C. Forbes; T. A. Hutchinson; J. G. Beaudoin; W. D. Dauphinee; D. J. Hollomby; Ronald D. Guttmann

A prospective study of the clinical and pathological sequelae of hepatitis B disease in 22 immunosuppressed renal transplant patients is reported. All patients had allografts that functioned for more than 1 year, and all were hepatitis B surface antigen (HB8Ag)-positive following transplantation. None of the 18 patients who had serial HB8Ag tests converted to HB8Ag negative. Serial liver biopsies were performed in 19 patients and one liver biopsy was available in the remaining three patients. Follow-up ranged from 12 to 93 months. Seven patients ultimately developed cirrhosis, 6 developed chronic active hepatitis, 5 developed chronic persistent hepatitis, and in 4 the presence of HB virus in hepatocytes was the sole morphologic alternation. The initial liver biopsy was not an accurate predictor of ultimate severity of liver disease because 5 of the 12 patients with virus only or chronic persistent hepatitis subsequently developed chronic active hepatitis or cirrhosis. Clinical liver dysfunction occurred in 8 patients, all of whom had chronic active hepatitis or cirrhosis. Three patients died with hepatic failure and 2 with hepatoma. The risk of death from liver disease in HB8Ag-positive renal transplant patients was 5% per patient-year. For comparison, 10 HB8Ag-positive patients whose renal failure had been treated by hemodialysis were also studied over a comparable period. Biochemical evidence of persistent liver dysfunction recurred in 1 patient only; 4 patients converted to the HB8Ag-negative state; and no patient has died from complications of liver disease. We conclude that in the immunosuppressed renal transplant patient HB infection often results in the development of chronic active hepatitis, leading to cirrhosis and death from hepatoma and hepatic failure.


The Lancet | 1998

The case for “presumed consent” in organ donation

Ian Kennedy; Ra Sells; As Daar; Ronald D. Guttmann; R Hoffenberg; M Lock; J Radcliffe-Richards; Nicholas L. Tilney

Is there a moral case for changing the law regulating organ donation from a system of “contracting in” to “contracting out” or “presumed consent” in those countries that have not yet done so? Contracting in refers to a system in which the law requires that donors and/or relatives must positively indicate their willingness for organs to be removed for transplantation. In a contracting out system, organs may be removed after death unless individuals positively indicate during their lifetimes that they did not wish this to be done, a system also known as presumed consent. We start with the premise that any measure that increases the supply of organs for transplantation is a good thing. If the contracting out system were to achieve this, the onus would then be on those who oppose it to demonstrate that the benefit that flows from it is outweighed by the harm. Why change the law? Since 1990 in those countries that have a contracting in system in place the number of cadaver organs available for transplantation has not kept up with demand; indeed the gap is widening. 1,2


Science | 1968

Pathogenesis of a Local Graft versus Host Reaction: Immunogenicity of Circulating Host Leukocytes

William L. Elkins; Ronald D. Guttmann

A local invasive-destructive reaction typical of that seen in allograft rejection occurs when Lewis rat spleen cells are inoculated under the capsule of Lewis kidney freshly grafted into F1 hybrid hosts. Thus the donor lymphoid cells can be immunogenically stimulated by circulating host leukocytes and the interaction of these two cell populations results in nonspecific damage to kidney parenchyma. The results indicate that passenger leukocytes in organ allografts may be important immunogenic agents.


Metabolism-clinical and Experimental | 1983

Spontaneous diabetes mellitus syndrome in the rat. IV. Immunogenetic interactions of MHC and non-MHC components of the syndrome.

Eleanor Colle; Ronald D. Guttmann; Thomas A. Seemayer; Frederic Michel

We have examined the frequency of three phenotypic characteristics of the syndrome of spontaneous diabetes (overt IDDM, lymphocytic infiltration of the pancreas, and depression of T lymphocytes) in the offspring of crosses between IDDM BB rats and rats of strains with the same and different RT1 genotypes. On the basis of these observations we propose that there are at least three components of the diabetic syndrome in the rat: (1) a requirement for the RT1u haplotype from the BB strain or a gene in close linkage with the gene coding for this haplotype, (2) a susceptibility for development of insular, periductular, or intraacinar lymphocytic infiltration in the pancreas, and (3) a susceptibility to depression of T lymphocytes. Interactions between these components as well as with other genetic and environmental factors contribute to the full expression of the syndrome.


Immunogenetics | 1984

Biochemical markers in inbred strains of the rat (Rattus norvegicus).

K. Bender; Mark Adams; Peter R Baverstock; Maria den Bieman; S. Bissbort; Radim Brdička; Geoffrey W. Butcher; Donald V. Cramer; Otto von Deimling; Michael F. W. Festing; Eberhard Günther; Ronald D. Guttmann; Hans J. Hedrich; Philip B. Kendall; Reinhard Kluge; René Moutier; Babette Simon; James E. Womack; Junzo Yamada; Bert van Zutphen

Klaus Bender 1, M a r k Adams 2, Peter R. Baverstock 2, Maria den Bieman 3, Siegbert Bissbort 1, Rad im Brdi~ka 4, Geoffrey W. Butcher 5, Dona ld V. Cramer 6, Otto yon Deimling 7, Michael F .W. Festing 8, Eberhard Gtinther 9, Rona ld D. G u t t m a n n 1°, Hans J. Hedrich 11, Philip B. Kendall 12, Reinhard Kluge i t , Ren6 Moutier 13, Babette Simon 7, James E. W o m a c k ~4, Junzo Yamada ~5, and Bert van Zutphen 3

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Eleanor Colle

Montreal Children's Hospital

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Merrill Jp

Howard Hughes Medical Institute

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David J. Hollomby

University of Western Ontario

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