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Biomedical subjects

R S Fennell

Publications and source records attributed to R S Fennell.

At least 55 records · Page 3Linked to original sources

Total parathyroidectomy and autotransplantation for tertiary hyperparathyroidism in children with chronic renal failure.

An association between chronic renal failure and skeletal deformities in the adolescent patient was first documented by Lucas in 1883. Since then it has been established that the kidneys play a major role in the regulation of calcium, phosphate, and parathyroid hormone, and that chronic renal failure is characterized by profound alterations in the normal metabolic homeostasis of the human body. With the hyperphosphatemia of uremia, compensatory hyperparathyroidism is also a well known complication. Due to these factors, loss of normal renal function ultimately leads to derangement in mineral and bone metabolism resulting in severe skeletal deformities. Reports in the English literature suggest that the changes of renal osteodystrophy are much more pronounced in the pediatric patient, as compared to those in the adult. In the last two decades, renal transplantation has come to be recognized as a satisfactory modality for controlling renal failure and its complications. This procedure is often not available as an option, however, in small patients, especially those under three years of age. The pediatric nephrologist is often forced to manage these patients for long periods with conservative therapy, in an attempt to control the ravages of renal osteodystrophy. The problem becomes unmanageable when the compensatory hyperparathyroidism proceeds to autonomy. When this occurs, despite maintenance of normal serum calcium levels, the renal osteodystrophy progresses rapidly, producing pain, deformities and growth retardation. At this point, the condition is often refractory to medical management and resection of parathyroid tissue remains the only satisfactory modality for control.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic Kidney Disease-Mineral and Bone Disorder↗

Role of regular and leukocyte-free blood transfusions in the generation of broad sensitization.

The factors associated with the development of humoral sensitization were studied prospectively in 30 previously transplanted patients immediately after graft rejection. Lymphocyte antibodies were measured both by conventional cytotoxicity in 30 panel cells and by flow cytometry in up to 10 target cells. Although lymphocyte antibodies induced by graft rejection alone were detected in 12 of 26 patients (46%), lymphocytotoxic antibodies were present in only 2 of 27 patients. Of the 25 patients without lymphocytotoxic antibodies, 13 developed them later. In all cases panel antibody reactivity developed after the patients received blood transfusions. No other factor was associated with the development of lymphocytotoxic antibodies, including transplant nephrectomy. There were 12 patients who remained negative for lymphocytotoxic antibodies even though 5 of them were transfused. The powerful role of blood transfusions in the generation of broad sensitization was further documented in 5 patients who received blood units completely depleted of leukocytes by cottonwool filtration and red cell washing. Four of these patients showed significant increases in the level of lymphocytotoxic antibodies, even when stored blood units were used. One additional patient became broadly sensitized by the transfusion of frozen blood. These results show (A) that broad sensitization may not develop if patients are not transfused after graft rejection; (B) that blood transfusions lead to broad sensitization in most (76%) pretransplanted patients; and (C) that transfusion of leukocyte-free blood may delay, but not avoid, the development of broad sensitization.

Autoantibodies↗

Planned random donor blood transfusion in preparation for transplantation. Sensitization and graft survival.

Random donor blood transfusions were used to prepare 183 prospective recipients for one-haplotype living-related donor (LRD) grafts or cadaver donor (CD) grafts. Five units of packed red blood cells were administered over a 7-10 day period, and weekly sera were monitored for six weeks. Sensitization was uncommon in men and nulliparous women (8/153), was of low reactivity, and was not a barrier to transplantation. Multiparous women had a 44% frequency of sensitization on presentation and 11/24 initially lacking cytotoxicity developed reactive serum following transfusion. Single-haplotype LRD recipients had 96% one-year graft survival. CD recipients had one-year graft survival of 72%. The rate of transplantation in surviving candidates exceeded 90%, and supports the hypothesis of a protective immune response.

Blood Transfusion↗

Effects of kidney transplantation on cognitive performance in a pediatric population.

The cognitive functioning of 20 children and adolescents with end-stage renal disease was assessed 1 to 3 weeks prior to the onset of hemodialysis, and at 1 month and 1 year after successful kidney transplantation, and results were compared with those of a matched control group. A battery of intelligence, achievement, problem solving, learning, memory, and attention tasks were administered. Both groups had significantly improved scores over time on most measures. The group with renal disease exhibited significantly greater improvement than the control group from initial testing to 1 month after transplantation on the performance IQ and full-scale IQ as well as in mathematics achievement. This significant difference was not maintained, however, at 1 year after transplantation. Cognitive performance was less impaired the later the onset of renal failure or the fewer the years in end-stage renal disease. BUN nitrogen, serum creatinine levels, and BP did not consistently correlate with any of the cognitive or academic achievement measures.

Achievement↗

Continuous ambulatory peritoneal dialysis in a pediatric population.

Seven children aged from 6 weeks to 14 years were treated for end-stage renal disease by continuous ambulatory peritoneal dialysis (CAPD) for 60 patient months. Satisfactory control of their uremia was achieved. Peritonitis was diagnosed on seven occasions (one case per 8.6 patient months) and did not interfere with continuation of dialysis or decrease peritoneal membrane permeability. Patients older than 5 years grew at rates comparable with those of patients receiving hemodialysis. Two infants receiving CAPD exhibited normal growth rates. Families demonstrated good psychosocial adjustment to the technique. Thus, CAPD seems to be a satisfactory alternative to hemodialysis for long-term therapy .

Adolescent↗

Renal growth and scarring in kidneys with reflux and a concentrating defect.

A study was done to determine if kidneys with reflux and an associated renal concentrating defect grew less well and had more scars than kidneys with reflux but no renal concentrating defect. To test our hypothesis we measured renal growth and assessed radiographs for renal scars in 11 children with and 20 children without a renal concentrating defect. Kidneys with reflux and a renal concentrating defect grew less well and had more scars than those kidneys with reflux but no renal concentrating defect. A persistent renal concentrating defect may be a predictor of kidneys more likely to have impaired growth and renal scars.

Child↗

Steroid-induced diabetes in pediatric renal transplant recipients.

Seven patients in a series of 79 children receiving 101 kidney transplants developed steroid-induced diabetes. Black children, recipients of cadaveric allografts, and patients receiving higher average daily prednisone dosage were more likely to develop hyperglycemia. The diabetes was transient and easily controlled. No patient developed permanent insulin dependence. No patients exhibited is let cell autoantibodies or an HLA haplotype associated with diabetes. Oral glucose tolerance testing demonstrated significant hyperglycemia with an inadequate insulin response. Three patients also exhibited unusual complications; two had cerebral vascular accidents (CVA) and one developed aspergillosis in a native kidney. Pediatric patients exhibiting steroid-induced diabetes following kidney transplantation may constitute a group at greater risk for complications.

Adolescent↗

Hyperparathyroidism and anemia in chronic renal failure.

The clinical course of an adolescent on chronic hemodialysis with severe hyperparathyroidism, osteodystrophy and profound anemia is described. After 1,25,dihydroxycholecalciferol was instituted for therapy, bone disease improved as evidenced by radiographic findings. Transfusion requirements diminished and bone marrow fibrosis on serial biopsies decreased significantly. These therapeutic results link hyperparathyroidism with the pathogenesis of anemia in chronic renal failure.

Anemia↗

Osteonecrosis of the femoral head and condyle in the post transplantation courses of children and adolescents.

The clinical courses of 29 children and adolescents who received their first renal allografts at the University of Florida from 1973 to 1979 were reviewed for the development of osteonecrosis. A minimum follow-up period of 24 months with adequate allograft function was required for inclusion in the study. The incidence of post transplantation osteonecrosis was 21%. The presence of osteodystrophy prior to transplant was strongly correlated with osteonecrosis. Dialysis against high calcium baths prior to transplantation played a protective role. Extensive reviews of their records failed to clearly identify other predisposing factors. Osteonecrosis of the knee was treated with plaster immobilization and osteonecrosis of the femoral head by resection arthroplasty and angulation osteotomy. Improved functional results were obtained on the Iowa Hip Rating Scales.

Adolescent↗

Liver dysfunction in children and adolescents during hemodialysis and after renal transplantation.

Liver dysfunction is common in patients on hemodialysis or during the posttransplant period. Twelve children in the End-Stage Renal Disease Program at the University of Florida ranging in age from 4 to 18 years, developed persistent, elevated liver enzymes (SGOT or SGPT greater than 100 IU/liter) during hemodialysis in preparation for renal transplantation. Eleven of 12 developed enzyme elevations within six weeks of the initiation of hemodialysis. The other child exhibited enzyme elevations after one year on dialysis while awaiting a second transplant. Most of the children were anicteric and asymptomatic. Potential hepatotoxic drugs were discontinued when serum transaminase elevations were noted. Hepatitis B surface antigenemia was associated with enzyme elevations in one patient; cytomegalovirus seroconversion had occurred in eight patients, but only three had associated enzyme elevations. Liver biopsies were performed in all the patients before or at the time of renal transplantation. The histology was variable and ranged from normal in six patients, mildly abnormal with changes compatible with acute hepatitis in four patients, and granulomatous hepatitis in one patient, to severely abnormal with chronic hepatitis inthe remaining patient. Seven of the 12 children underwent successful transplantation with return of enzyme levels to normal in five and persistent elevations in the others. These findings suggest that evaluation of liver histology provides the only accurate means of assessment of persistent liver dysfunction in children and adolescents on hemodialysis and after renal transplantation.

Adolescent↗

Hypertension in a pediatric and adolescent population following kidney transplantation.

The post-renal transplant courses of 53 children and adolescents were evaluated for the prevalence and the etiology of hypertension. The blood pressures were averaged over specific time periods following transplantation and converted to percentile ranks according to standards for age. The number of antihypertensives employed to control blood pressure was assessed. Factors such as sex, obesity, race, donor source, antigen match, steroid administration, rejection, recurrent glomerulonephritis, pre-transplant nephrectomy, renal function and proteinuria were assessed as to their importance in producing hypertension or normotension in the post-transplant period. The average blood pressure was well within acceptable range shortly after transplantation. The patients requiring antihypertensives to control blood pressure dropped by two years post transplant. Chronic rejection was by far the most important factor influencing average blood pressure and the need to employ antihypertensives. Alternate-day prednisone and good graft function were important in establishing the normotensive state.

Adolescent↗

Treatment of Bartter's syndrome with indomethacin.

Two patients with Bartter's syndrome were treated with indomethacin (2 mg/kg/day). The administration of the drug resulted in weight gain; a decrease in the rate of urinary excretion of sodium and inorganic phosphate suggesting an increase in proximal tubular reabsorption; an increase in serum potassium concentration, with a transient decrease in the rate of urinary potassium excretion in one patient; and a decrease in plasma renin activity and in the rate of urinary aldosterone excretion. Since indomethacin has been shown to inhibit prostaglandin synthetase, these observations support the hypothesis that prostaglandin excess is a basic pathogenic mechanism in Bartter's syndrome.

Adolescent↗

Encephalopathy in children with chronic renal failure.

Progressive encephalopathy with characteristic clinical features and electroencephalographic findings has been reported many times in adult patients treated with maintenance hemodialysis. Two children with chronic renal failure developed a similar encephalopathy prior to their second birthdays and before the initiation of dialysis. Both children required parathyroidectomy for control of severe hyperparathyroidism with persistent hypercalcemia. Slight improvement followed this procedure in one patient. Selected biochemical abnormalities in serum and in brain tissue specimens were compared to those of neurologically unaffected children. Results of thes studies suggest that a direct toxic effect of either aluminum or calcium on the brain does not play an etiologic role in this disorder.

Aluminum↗

Evaluation of an educational program on compliance with medication regimens in pediatric patients with renal transplants.

An educational program was initiated in an attempt to improve compliance in taking medications among pediatric renal transplant patients. Compliance was assessed by pill counts and by knowledge about medications by interview and questionnaire before, during, and after a six-month study period. Forty-three percent of the population was initially found to be in some way noncompliant with medication regimens, and 19% remained so after extensive counseling and instruction. Factors associated with noncompliance were adolescence, female sex, and family instability. Compliance was associated with direct parental involvement and voluntary maintenance of medication calendars. Although knowledge about drugs significantly improved, there was no correlation with compliance; motivational factors appeared to be of greater importance.

Adolescent↗