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L M Sandler

Publications and source records attributed to L M Sandler.

10 recordsLinked to original sources

An evaluation of the distinction of ectopic and pituitary ACTH dependent Cushing's syndrome by clinical features, biochemical tests and radiological findings.

The efficiency of various laboratory and radiological investigations in the differentiation of ectopic from pituitary dependent Cushing's syndrome was studied, based on findings in 23 patients with verified Cushing's disease and seven patients with the ectopic ACTH syndrome. Clinical features strongly favouring the ectopic type were male sex and history for less than 18 months. Basal biochemical features strongly indicating the ectopic syndrome included plasma K+ less than 3.0 mmol/l and HCO3 greater than 30 mmol/l; serum cortisol at 9 a.m. or midnight of greater than 800 nmol/l; urine free cortisol greater than 1300 nmol/24 hours; plasma ACTH greater than 100 ng/l. In the high-dose dexamethasone suppression test, suppression by less than 50 per cent of 9 a.m. serum cortisol, urine free cortisol or 17-oxogenic steroids was usually indicative of an ectopic source of ACTH. A mean suppressed value of greater than 450 nmol/l for the 9 a.m. and midnight cortisol combined occurred in all of those with the ectopic syndrome, but in none of the 23 patients with Cushing's disease. For urine free cortisol, a mean suppressed value of less than 1000 nmol/24 hours was found in all patients with Cushing's disease, but in none of those in the ectopic group. In the metyrapone test, there was an increase of less than or equal to 3-fold in 11-deoxycortisol at 24 hours in patients with ectopic ACTH; the increase was greater than 3-fold in all but one of the patients with Cushing's disease. Failure to respond to either dexamethasone or metyrapone was found in only one of the patients with Cushing's disease (Patient 16); in the ectopic group, all patients except Patient D failed to respond to either test. It is concluded that patients presenting with clinically obvious Cushing's syndrome along with measurable plasma ACTH can be reliably divided by conventional tests into those that are driven from the pituitary and those driven by ectopic ACTH.

ACTH Syndrome, Ectopic

Pharmacokinetics of the long-acting somatostatin analogue octreotide (SMS 201-995) in acromegaly.

A single-dose study was performed to examine the pharmacokinetics of subcutaneous octreotide in acromegalic patients and to investigate the relationship between growth hormone and the elimination half-life of the drug. Fourteen acromegalic patients (six men and eight women; age range 35-59 years) who had previously received conventional treatment were studied. Two subjects were on long-term octreotide which had been discontinued 72 h before the study. Octreotide 100 micrograms was administered subcutaneously and plasma samples taken every 10 min for 1 h and then hourly for up to 8 h. Growth hormone was measured at 0, 2 and 8 h. Octreotide was rapidly absorbed with a mean (+/- SEM) t1/2abs of 5.4 min (+/- 0.8) peaking at a mean plasma concentration of 3.4 nmol/l (+/- 0.2) in 27.4 min (+/- 3.7). The monoexponential elimination phase had a mean half-life of 110 min (+/- 9.6). The apparent volume of distribution was 29.4 1 (+/- 1.9) and total clearance was 172 ml/min (+/- 10.4). These results were similar to those obtained in normal volunteers. There was no simple relationship between the level of growth hormone and the half-life of octreotide. Growth hormone levels ranged from 2.5 to 34.0 mIU/l but were only greater than 10 mIU/l in three subjects. Further studies of octreotide pharmacokinetics are needed in untreated patients with acromegaly with raised growth hormone levels.

Acromegaly

Effective long-term treatment of acromegaly with a long-acting somatostatin analogue (SMS 201-995).

Nine acromegalic patients, six previously untreated, were studied before and after 3-15 months of treatment with a long-acting somatostatin analogue (SMS 201-995; 100 micrograms injected s.c. three times daily). During treatment, the mean (+/- SEM) 24-h GH concentration fell from 82 +/- 22 mIU/l to 33 +/- 7 mIU/l (P less than 0.001), and eight of the 9 patients showed a reduction of at least 50% in GH levels in the fasting state and/or during a glucose tolerance test. There was a significant 30% fall in serum concentrations of insulin-like growth factor (IGF-1) with SMS. All patients showed rapid clinical improvement, with diminished sweating and headaches, and reduction in skinfold thickness, hand volumes and finger size. Computer tomographic scanning of the pituitary in eight patients showed no change in the size of the pituitary tumour during treatment. The only side-effects of SMS noted were transient abdominal discomfort and loose stools in two patients on initiating therapy. Although fasting plasma glucose concentration did not change during treatment (5.4 +/- 0.3 vs 5.5 +/- 0.3 mmol/l), mean 24-h plasma glucose concentration was higher with SMS (6.6 +/- 0.5 mmol/l vs 6.0 +/- 0.4 mmol/l; P less than 0.02). Mean 24-h plasma insulin concentration fell from 87 +/- 11 mIU/l before treatment to 39 +/- 6 mIU/l during treatment (P less than 0.005). No change in other anterior pituitary hormones was observed. SMS appears to be a safe, rapidly effective, long-term treatment for certain patients with acromegaly.

Acromegaly

Long term follow-up of patients with Cushing's disease treated by interstitial irradiation.

The first 86 patients with Cushing's disease treated with interstitial irradiation (by needle implantation) as the sole therapy were reviewed. In the 82 patients who were reassessed 1 yr after treatment 63 (77%) achieved remission. This study comprises the outcome and complications in the 54 patients who had a remission and whom we were able to follow. The follow-up period ranged from 3-26 yr (mean, 10.5) from the time of remission. No instance of clinical or radiological relapse has occurred. Of these 54 patients, yttrium-90 alone was used in 32, of whom 12 (37%) required corticosteroid or T4 replacement therapy in a mean time of 3.5 months; in 7 of these 12 we elected to give an ablative dose. Gold-198 alone was used in 15 patients, of whom 7 (47%) developed hypopituitarism in a mean time of 76 months. Both isotopes were used in 7 patients. A diurnal serum cortisol rhythm was found in 28 of the 31 patients who were not receiving corticosteroid therapy. In 5 of the 7 patients with an initially abnormal pituitary fossa, serial radiological studies revealed remodelling in 3. There have been no complications in the last 17 years. Pituitary implantation with yttrium-90 is an effective alternative to transsphenoidal hypophysectomy, with a high remission rate, no recurrence (as yet), no operative complications, and avoidance of hormone replacement in the majority.

Adolescent

Combined use of vasopressin and synthetic hypothalamic releasing factors as a new test of anterior pituitary function.

Nine normal volunteers and 15 patients with pituitary disorders were given a combined test of anterior pituitary function using four hypothalamic releasing factors and arginine vasopressin. Rapid sequential intravenous infusions of human corticotrophin releasing factor 100 micrograms, growth hormone releasing factor 100 micrograms, luteinising hormone releasing hormone 100 micrograms, and thyrotrophin releasing hormone 200 micrograms were administered. Arginine vasopressin (10 pressor units) was given intramuscularly at the same time. Plasma or serum samples were assayed for concentrations of cortisol, growth hormone, luteinising hormone, follicle stimulating hormone, prolactin, and thyroid stimulating hormone at multiple times for 120 minutes. No troublesome side effects occurred. The results of the releasing factor combined test with arginine vasopressin were compared in the same subjects with a conventional combined test using insulin together with thyrotrophin releasing hormone and luteinising hormone releasing hormone. No difference was observed in the basal and peak concentrations of luteinising hormone, follicle stimulating hormone, thyroid stimulating hormone, and prolactin. Both cortisol and growth hormone responses to the releasing factors with arginine vasopressin were much greater than those seen with insulin induced hypoglycaemia or the combined releasing factors without arginine vasopressin. Patients with pituitary hypo-function were similarly recognised in both studies. There was a rapid increase in all hormone values with a peak usually by 60 minutes. In most people adequate assessment of individual hormone reserves may be achieved using basal, 30 minute, and 60 minute samples. This new combined releasing factor test appears to be a safe, rapid, and useful test of anterior pituitary function.

Adult

1, 25-dihydroxycholecalciferol in the pathogenesis of the hypercalcaemia of sarcoidosis.

A 36-year-old man with sarcoidosis had four episodes of hypercalcaemia in seven years, all of them during the summer months. Measurement over three years showed that hypercalcaemia was associated with small seasonal increases in serum-25-hydroxycholecalciferol within the normal range. These changes could be mimicked by the administration of 3000 units of vitamin D3 daily. Serum 1, 25-dihydroxycholecalciferol concentrations ranged between 26--62 pg/ml when serum calcium was normal, but were strikingly high, up to 137 pg/ml, when the patient was hypercalcaemic. These studies show for the first time that hypercalcaemia in sarcoidosis is associated with abnormally high circulating concentrations of 1, 25-dihydroxycholecalciferol, probably as a result of overproduction of this, the hormonal form of vitamin D.

Adult