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R S Rodger

Publications and source records attributed to R S Rodger.

70 records · Page 4Linked to original sources

Anterior pituitary dysfunction in patients with chronic renal failure treated by hemodialysis or continuous ambulatory peritoneal dialysis.

Cortisol, prolactin, and growth hormone responses to insulin-induced hypoglycemia were measured in 20 patients undergoing continuous ambulatory peritoneal dialysis or intermittent hemodialysis. The plasma cortisol responses were normal; however, the increments in serum prolactin and growth hormone concentrations were impaired in most patients. The growth hormone responses were lower (p less than 0.05) in those patients treated by continuous ambulatory peritoneal dialysis, but there were no other significant differences between the two patient groups. These results show that anterior pituitary dysfunction persists in some patients with chronic renal failure despite maintenance dialysis therapy.

Adolescent↗

Hypothalamic-pituitary-adrenocortical suppression and recovery in renal transplant patients returning to maintenance dialysis.

Sixty-six per cent of a group of 21 renal transplant recipients with chronic renal failure were shown to have adrenal suppression due to glucocorticoid treatment. Gradual withdrawal of steroids in these patients returning to maintenance dialysis therapy was achieved with few symptoms of hypoadrenalism. Adrenal recovery occurred in 52 per cent of patients after three months and 71 per cent after six months. However, the plasma cortisol response to insulin-induced hypoglycaemia, studied in patients in whom adrenal recovery had been demonstrated, was impaired in 46 per cent of cases. These results indicate that corticosteroids in renal transplant recipients induce profound hypothalamic-pituitary-adrenal suppression which is slow to recover. Such patients returning to maintenance dialysis are at risk of acute adrenocortical insufficiency for several months. Although withdrawal of steroids can be achieved safely, cover during periods of stress should be given until the hypothalamic-pituitary-adrenal axis has been shown to respond normally.

Adolescent↗

Loss of pulsatile luteinising hormone secretion in men with chronic renal failure.

In an attempt to determine the nature of hypothalamic and pituitary dysfunction in renal failure the secretory patterns of luteinising hormone were measured in men with end stage renal disease and compared with those in healthy controls and renal transplant recipients of similar age distribution. Mean luteinising hormone and oestradiol concentrations were significantly higher and the number of luteinising hormone secretory pulses was significantly lower in uraemic men compared with controls. Plasma testosterone and oestradiol concentrations were significantly lower in renal transplant recipients than normal men, but there were no significant differences in mean gonadotropin concentrations or the number of pulses of luteinising hormone between the two groups. As pulses of luteinising hormone are thought to reflect episodic gonadotropin releasing hormone from the hypothalamus these data suggest that uraemia interferes with central mechanisms controlling synchronised release of gonadotropin releasing hormone. This defect appears to be reversible after successful transplantation.

Adult↗

Effect of storage on measurement of ionized calcium in serum of uremic patients.

We studied, in 70 acidotic and non-acidotic uremic patients, the analytical variance in serum ionized calcium as related to duration and temperature of storage. Storage of serum or whole blood at 4 degrees C for as long as 6 h did not significantly alter the measured concentration of ionized calcium in the serum. Storage at room temperature for 6 h, or longer at 4 degrees C or -20 degrees C, resulted in inaccuracies in 39 to 79% of the samples of serum and in 38 to 92% of the samples of whole blood. These errors were not negated by correcting the values for ionized calcium to a pH of 7.40. Indeed, corrected values for calcium were even more unreliable in acidotic patients. We conclude that samples from uremic patients should be analyzed for ionized calcium within 2 h, or within 6 h if stored at 4 degrees C.

Acidosis↗

Factors influencing normal reference intervals for creatinine, urea, and electrolytes in plasma, as measured with a Beckman Astra 8 Analyzer.

In a study of 514 healthy adults, we used a Beckman Astra 8 Analyzer to establish normal reference intervals for plasma creatinine, urea, and electrolytes. For potassium and chloride these were considerably lower and higher, respectively, than previously reported ranges. All of these analytes showed significant sex-related differences; all except chloride showed age-related changes. The relationship of these biochemical indices to fasting, cigarette smoking, alcohol intake, regular exercise, and the contraceptive pill--independent of these age- and sex-related differences--was assessed by multiple linear regression. The effect was significant in each case. Our results underline the importance of regular review of reference values.

Adolescent↗

Factors affecting development of peritonitis in continuous ambulatory peritoneal dialysis.

A questionnaire based survey in patients receiving continuous ambulatory peritoneal dialysis showed that there was an increased incidence of upper respiratory tract symptoms (suggestive of viral illness) in the 14 days before the development of peritonitis. No other factors were identified that might distinguish patients who develop peritonitis. The possibility that viral infections predispose to peritonitis by altering host defence mechanisms in patients receiving this form of renal replacement therapy warrants further study.

Humans↗

Surgical treatment of hydrothorax complicating continuous ambulatory peritoneal dialysis.

Acute hydrothorax is a well recognized complication of continuous ambulatory peritoneal dialysis (CAPD) and is usually regarded as a contra-indication to the further use of this form of dialysis. We report the first case of treatment by surgical closure of a communication between the peritoneal and the right pleural cavity enabling CAPD to continue successfully. The development of an acute hydrothorax on CAPD is therefore not a reason to abandon this form of dialysis and can be treated by a simple thoracic surgical procedure.

Aged↗

Prevalence and pathogenesis of impotence in one hundred uremic men.

In a study of dialysis patients 79% of men complained of sexual dysfunction and 61% erectile impotence following uremia and the onset of regular dialysis therapy. Plasma testosterone levels were significantly higher in patients treated by continuous ambulatory peritoneal dialysis (p = 0.001) but the incidence of sexual dysfunction was not different from patients treated by hemodialysis. Although follicle-stimulating hormone levels were higher (p = 0.001) and penile blood pressure index levels lower (p less than 0.05) in patients with impotence, sexual function was not improved by exogenous testosterone, and vasculogenic impotence was identified in only 6% of patients. These findings suggest that a major component of uremic impotence is unrelated to primary testicular failure or penile vascular insufficiency.

Adult↗

Cardiac and vascular abnormalities in renal transplant patients: differential effects of cyclosporin and azathioprine.

Renal transplant patients die prematurely of cardiovascular disease and LV hypertrophy is now recognised as an important adverse prognostic indicator. This study investigated the factors implicated in the development of echocardiographic abnormalities (including LV hypertrophy) and the possible differential effects of treatment with cyclosporin and azathioprine. A cross-sectional study was undertaken in 46 patients randomly assigned to immunosuppressant treatment with either cyclosporin or azathioprine at 1 year post-transplantation: patients were studied not less than 5 years after assignment to cyclosporin (CyA) - or azathioprine (Aza)-based treatment regimens. Although clinic blood pressure control was not different in the two treatment groups, 24 hour ambulatory BP (ABP), particularly night-time BP, was significantly higher in the CyA group. There was a trend for both left ventricular hypertrophy (61 vs. 43%) and carotid wall thickening (43 vs. 26%) to be more common in the CyA group though this failed to achieve statistical significance. Left ventricular mass was determined by ABP, rather than clinic BP, and was also associated with increased QT dispersion. Multivariate analysis identified that 24 hour ambulatory systolic blood pressure (ASBP) and time on renal replacement therapy (RRT) were the major determinants of LV mass. Thus, despite the absence of differences in clinic BP measurements, CyA treatment was associated with higher rates of cardiovascular functional and structural abnormalities. This small scale study has identified cardiovascular functional and structural abnormalities in renal transplant patients, particularly in those receiving CyA-based immunosuppressive therapy. However, rather than reflecting a direct effect of CyA they are related to increased 24 ABP (but not clinic BP). These data suggest that ABP should be used to monitor and target antihypertensive therapy in this high risk patient group. Moreover, the future use of non-calcineurin inhibitor immunosuppressant therapy may have benefits on blood pressure control and LV mass.

Adult↗