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Objectives: Research studies have reported that about a third of individuals with phaeochromocytoma/paraganglioma (PPGL) have an inherited predisposition, although the frequency of specific mutations can vary between populations. We evaluated VHL, SDHB and SDHD mutation testing in cohorts of patients with non-syndromic PPGL and head and neck paraganglioma (HNPGL)., Design: Prospective, observational evaluation of NHS practice., Patients: Individuals with PPGL/HNPGL referred to a supraregional genetics testing service over a 10-year period., Measurements: Clinical (age, tumour site, malignancy, etc.), mutation frequencies and characteristics., Results: A total of 501 probands with PPGL (n = 413) or HNPGL (n = 88) were studied. Thirty-one percent of patients with PPGL presented had a pathogenic mutation in SDHB, SDHD or VHL. Mutation detection rates were highest in those with a positive family history (62%), malignancy (53%), multiple tumours (33%) or PGL (44%). Twenty-eight percent of individuals with a single sporadic phaeochromocytoma had a mutation. Overall, 63% of patients with HNPGL had a mutation (92% of those with a family history, 89% of those with multicentric tumours and 34% of those with a single sporadic HNPGL). Penetrance was calculated in 121 SDHB mutation-positive probands and 187 of their mutation-positive relatives. Most relatives were asymptomatic and lifetime penetrance in non-proband SDHB mutation carriers was <50%., Conclusions: Practice-based evaluations of genetic testing in PPGL reveal high mutation detection rates. Although clinical criteria can be used to prioritize mutation testing, mutations were detected in 'low risk groups' indicating a need for comprehensive and inexpensive genetic testing strategies for PPGL and HNPGL., (© 2012 John Wiley & Sons Ltd.)

Objective: Addition of dehydroepiandrosterone sulphate (DHEAS) to standard pituitary replacement may improve quality of life and glucose metabolism. Conflicting results from the previous work probably relate to differences in populations studied and assessment techniques used. We examined the effects of DHEAS on insulin action and the quality of life in female patients with hypopituitary hypoadrenalism., Design: Randomized, double-blind, placebo-controlled, crossover design was used. Patients received either DHEAS 50 mg daily or placebo for 12 weeks., Patients: Fourteen hypopituitary females on stable standard replacement therapy and with low DHEAS were enrolled., Measurements: Insulin action by euglycaemic hyperinsulinaemic clamp and extensive quality of life parameters were assessed after each treatment., Results: Serum DHEAS (DHEAS 5·4 ± 0·8 vs placebo <0·8 ± 0·0 μm; P < 0·001) and androstenedione (DHEAS 4·1 ± 0·8 vs placebo 1·3 ± 0·2 nm; P < 0·05) rose to within the normal range after DHEAS 50 mg daily. There were no differences between treatments in testosterone, sex hormone-binding globulin (SHBG) or IGF-1. Quality of life measures were unchanged after DHEAS. There were no differences between treatments in fasting glucose, serum insulin, HbA1c or in insulin action (glucose infusion rates required to maintain euglycaemia; DHEAS 21·9 ± 2·5 vs placebo 24·5 ± 2·1 μmol/kg/min; P = 0·4). Triglyceride concentrations were lower following DHEAS (DHEAS 1·24 ± 0·18 vs placebo 1·41 ± 0·19 mm; P < 0·05) but other lipid parameters remained unchanged., Conclusion: There were no differences compared with placebo in quality of life or insulin action after DHEAS replacement therapy for 12 weeks. These results do not provide evidence for the addition of DHEAS to standard hypopituitary replacement therapy., (© 2012 Blackwell Publishing Ltd.)

Objective: Patients with primary aldosteronism (PA) who are suitable for surgery should undergo adrenal computerised tomography (CT) and adrenal venous sampling (AVS). A retrospective study was performed of 100 patients with PA. We determined the optimal AVS lateralisation ratio for unilateral disease and reviewed adrenalectomy outcomes evaluating which characteristics predicted hypertension cure., Methods: AVS was performed in 93 patients. Lateralisation criteria were assessed using ROC curve analysis. The outcome of adrenalectomy was reviewed in 39 patients and predictive factors for cure determined using univariate and multivariate analysis., Results: Of previously published criteria, ROC curve analysis found a cortisol corrected aldosterone affected to unaffected (Aldo/Cort A:U) cut-off of 2·0 was the best predictor of adenoma identifying 80·4% of patients. A novel ratio calculated by dividing the affected to unaffected ratio by the unaffected to peripheral ratio [(Aldo/Cort A:U)/(Aldo/Cort U:IVC)] was successful in identifying 87·0% of patients. Cure rate for blood pressure after adrenalectomy was 38·5% with improvement in 59·0%. On univariate analysis, predictors of post-operative hypertension were increased weight, raised creatinine, left ventricular hypertrophy (LVH) and male sex. On multivariate analysis, male sex and higher pre-operative systolic blood pressure were predictive., Conclusions: Patients with PA should have CT scanning and AVS. Aldo/Cort A:U >2·0 is the most accurate of previously published ratios in predicting unilateral disease. When patients were carefully selected for surgery, 97% had cure or improvement in blood pressure control. Further confirmatory work is required on a novel ratio which was even more predictive in our series., (© 2011 Blackwell Publishing Ltd.)

Background: Peroxisomal proliferator-activated receptors (PPAR)- gamma are expressed abundantly in ACTH-secreting pituitary tumours. The PPAR-gamma activator rosiglitazone has been shown to suppress ACTH secretion in human adrenocorticotroph tumour cells in vitro, and prevent and reduce adrenocorticotroph tumour development in mouse models in vivo., Objective: To evaluate the effect of rosiglitazone in patients with persistently elevated plasma ACTH levels postbilateral adrenalectomy for Cushing's disease., Patients: Seven patients were treated with rosiglitazone 8 mg orally per day for 12 weeks., Measurements: Plasma ACTH was measured at two hourly intervals from 09:00 h to 17:00 h before and after 6 and 12 weeks of treatment., Results: Plasma ACTH at 09:00 hours immediately before the usual morning hydrocortisone dose was 2599.0 +/- 899.7 ng/l (mean +/- SEM) basally and 1547.6 +/- 515.7 ng/l after 12 weeks of rosiglitazone, whereas levels at 17:00 h were 1433.4 +/- 506.2 ng/l (mean +/- SEM) basally and 1122.3 +/- 460.9 ng/l at 12 weeks (all nonsignificant)., Conclusion: This study showed no effect of rosiglitazone treatment at maximum approved doses in lowering plasma ACTH levels in patients post bilateral adrenalectomy for Cushing's disease.

Objective: There have been a few reports on long-term remission rates after apparent early remission following pituitary surgery in the management of Cushing's disease. An undetectable postoperative serum cortisol has been regarded as the result most likely to predict long-term remission. Our objective was to assess the relapse rates in patients who underwent transsphenoidal surgery in order to determine whether undetectable cortisol following surgery was predictive of long-term remission and whether it was possible to have long-term remission when early morning cortisol was measurable but not grossly elevated. Endocrinological factors associated with late relapse were also studied., Patients: We reviewed the long-term outcome in 63 patients who had pituitary surgery for the treatment of Cushing's disease between 1979 and 2000., Measurements: Case notes were reviewed and the current clinical and biochemical status assessed. Our usual practice was that early after the operation, an 08:00 h serum cortisol was measured 24 h after the last dose of hydrocortisone. This was followed by a formal low-dose dexamethasone suppression test. Current clinical status and recent 24-h urinary free cortisol values were used as an index of activity of the Cushing's disease. If there was evidence suggesting relapse, a low-dose dexamethasone suppression test was performed. In many patients, sequential collections of early morning urine specimens for urinary cortisol to creatinine ratio were also performed in an attempt to diagnose cyclical and intermittent forms of recurrent hypercortisolism. We did this if there was conflicting endocrine data, or if patients were slow to lose abnormal clinical features., Results: Mean age at diagnosis was 40.3 years (range 14-70 years). Mean follow-up up time was 9.6 years (range 1-21 years). Forty-five patients (9 males/36 females) achieved apparent remission immediately after surgery and were subsequently studied long term. Of these 45 patients, four have subsequently died while in remission from hypercortisolism. Ten of the remaining 41 patients have relapsed. Of those 10, six demonstrated definite cyclical cortisol secretion. Two of the 10 had undetectable basal serum cortisol levels in the immediate postoperative period. Thirty-one patients are still alive and in remission. Fourteen (45%) of the 31 who remained in remission had detectable serum cortisol levels (> 50 nmol/l) immediately postoperatively, and remain in remission after a mean of 8.8 years. Our relapse rate was therefore 10/45 (22%), after a mean follow-up time of 9.6 years, with mean time to relapse 5.3 years., Conclusions: The overall remission rate of 56% (35/63) at 9.6 years follow-up is disappointing and merits some re-appraisal of the widely accepted principle that pituitary surgery must be the initial treatment of choice in pituitary-dependent Cushing's syndrome. Following pituitary surgery, careful ongoing expert endocrine assessment is mandatory as the incidence of relapse increases with time and also with increasing rigour of the endocrine evaluation. A significant number of our patients were shown to have relapsed with a cyclical form of hypercortisolism.

Objective: Hypercortisolism is associated with impaired glucose tolerance and insulin resistance. For many years hydrocortisone 30 mg was the standard total daily replacement dose in adult hypopituitarism. The use of this conventional dose has now been shown to result in mild biochemical hypercortisolism and might contribute to the increased cardiovascular risk reported in hypopituitarism. The use of lower doses of hydrocortisone replacement therapy might prevent some of the adverse metabolic effects seen with conventional doses., Patients: In a randomized crossover study we assessed peripheral and hepatic insulin action in 15 ACTH-deficient patients with normal glucose tolerance on two occasions while receiving either a low-dose oral hydrocortisone replacement (LOR) therapy (15 mg at 0800, 5 mg at 1700) or a physiological hydrocortisone infusion (PHI), which achieved physiological serum cortisol concentrations., Results: Exogenous glucose infusion rates required to maintain euglycaemia were similar for the LOR and the PHI protocols (26.2 +/- 0.4 vs. 23.8 +/- 0.6 micromol/kg/min, respectively). Endogenous glucose production was also similar (12.0 +/- 2.5 vs. 11.6 +/- 2.4 micromol/kg/min, respectively) and in the post-absorptive state suppressed to a similar extent following insulin (4.5 +/- 2.0 vs. 5.1 +/- 3.1 micromol/kg/min)., Conclusion: Hydrocortisone replacement therapy at a dose of 15 mg with breakfast, 5 mg with evening meal does not increase peripheral or hepatic insulin resistance when compared to a hydrocortisone infusion designed to simulate physiological serum cortisol concentrations.

Objective: The conventional dosage of hydrocortisone, used for many years in the management of hypopituitarism (30 mg per day), has now been shown to be more than is physiologically necessary. On this conventional corticosteroid therapy studies have demonstrated an increased prevalence of diabetes and impaired glucose tolerance, which may contribute to the increased vascular morbidity and mortality reported in the condition. In these studies no information is available on oral glucose tolerance test (OGTT) timing in relation to administration of oral steroid and variable hydrocortisone doses were employed., Patients: In order to assess glucose tolerance in patients treated with lower, more physiological doses, we performed a 75-g OGTT at least 1 month after hydrocortisone therapy was adjusted to 15 mg at 0800 h and 5 mg at 1700 h in 45 adult onset hypopituitary patients (30 M, 15 F). Mean (+/- SD) duration of hypopituitarism was 12 +/- 10 years, mean age 52 +/- 14 years and BMI 29.3 +/- 5.1 kg/m2. All were on hydrocortisone, 43 on thyroxine, 31 on sex steroids, 9 on desmopressin and 33 had documented growth hormone deficiency. Hydrocortisone 15 mg was taken at 0800 and the OGTT commenced at 0900., Results: Using standard WHO criteria 36 patients (80%) had normal glucose tolerance, 1 (2%) had newly diagnosed diabetes and 8 (18%) had impaired glucose tolerance. Using the recently announced American Diabetes Association criteria for diagnosis 96% had normal glucose tolerance, 2% had diabetes and 2% impaired fasting glucose., Conclusion: The markedly reduced prevalence of diabetes and impaired glucose tolerance on lower hydrocortisone replacement doses in our series of patients with hypopituitarism, not previously known to be diabetic, is of great interest. This lower prevalence may eventually result in reduced vascular complication rates.

Objective: To compare the use of 0900 h serum cortisol and both low and standard dose Synacthen tests, one week after pituitary surgery with an insulin hypoglycaemia test performed 4-6 weeks after surgery in assessing the integrity of the hypothalamic-pituitary-adrenal (HPA) axis., Design: 0900 h basal serum cortisol was measured on days 6 and 7 after pituitary surgery (24 h off replacement hydrocortisone) followed by a low dose Synacthen test (1 microg intravenously) on day 6 and a standard dose Synacthen test (250 microg intramuscularly) on day 7. Three to 5 weeks later an insulin hypoglycaemia test was performed on all patients. Both low and standard dose Synacthen tests were performed on control subjects using an identical protocol., Subjects: Forty-two patients (21 male, 21 female), median age 49 years (range 23-73) who had pituitary surgery (Cushing's disease excluded). One patient had undergone repeat surgery for residual tumour and was studied following each operation. Sixteen healthy normal volunteers, median age 37 years (range 21-55)., Measurements: Serum cortisol measured by radioimmunoassay., Results: Two standard deviations below the mean serum cortisol (logarithmic transformation) in the normal volunteers 30 minutes after low dose Synacthen (1 microg) was 496 nmol/l and after standard dose Synacthen (250 microg) was 504 nmol/l. A normal response was therefore taken as serum cortisol > 500 nmol/l at 30 minutes in both tests (using 496 and 504 nmol/l did not alter results). 0900 h serum cortisols 1 week after surgery were > 250 nmol/l in 31 patients and 29 of these had a normal response to hypoglycaemia (peak serum cortisol > 550 nmol/l). Of the remaining two patients, one had 0900 h serum cortisol on day 6 and 7 after surgery of 405 and 441 nmol/l with a peak serum cortisol response to hypoglycaemia of 451 nmol/l; the other patient had 0900 h serum cortisols of 416 and 251 nmol/l and a peak cortisol response to hypoglycaemia of 498 nmol/l. All eight patients who had a 0900 h serum cortisol < 100 nmol/l failed a subsequent insulin hypoglycaemia test. Seven discrepancies were noted between the low dose Synacthen test and the insulin hypoglycaemia test in the 41 patients who had both tests. In six of these, a subnormal response to low dose Synacthen was followed by a normal response to hypoglycaemia. Three discrepancies were noted between the standard dose Synacthen test and the insulin hypoglycaemia test in the 40 patients who had both tests. In all three cases a normal response to Synacthen was followed by a subnormal response to hypoglycaemia., Conclusions: A 0900 h serum cortisol < 100 nmol/l (24 h off replacement hydrocortisone) indicated ACTH deficiency and need for lifelong steroid replacement. A 0900 h serum cortisol > 450 nmol/l one week after pituitary surgery is highly suggestive of a normal cortisol response to hypoglycaemia. A 0900 h serum cortisol between 250 and 450 nmol/l one week after pituitary surgery permits safe withdrawal of steroid therapy pending an insulin hypoglycaemia test 1 month after surgery. Patients with 0900 h serum cortisol between 100 and 250 nmol/l should continue replacement steroids until definitive testing. Low dose and standard dose Synacthen tests 1 week after pituitary surgery are unreliable and should not be used.

Objective: To compare the insulin hypoglycaemia test with the short overnight metyrapone test in the assessment of the hypothalamic-pituitary-adrenal (HPA) axis posthypophysectomy., Design: Prospective comparative study of the insulin hypoglycaemia test and the overnight metyrapone test in 32 patients 4-6 weeks after pituitary surgery., Subjects: Thirty-two patients with known pituitary disease. None with present or previous Cushing's syndrome., Outcome Measurements: Maximum serum cortisol achieved during insulin induced hypoglycaemia compared with 0900 hours serum 11-deoxycortisol level following a weight related oral dose of metyrapone at 0000 h., Results: One of the 32 patients required further surgery and was studied twice after each operation. Thirty-three results are therefore compared. Twenty-six of these had a normal cortisol response of 550 nmol/l or above leading to the cessation of replacement hydrocortisone. Six of these 26 patients however, failed the metyrapone test (11-deoxycortisol level less than 200 nmol/l). After 3-40 months (median 20 months) of follow-up off steroid therapy, no patient to date has displayed any clinical evidence of steroid deficiency. Of the seven patients who failed the insulin hypoglycaemia test, six also failed the metyrapone test., Conclusions: The overnight metyrapone test identified more patients with possible ACTH deficiency than the insulin hypoglycaemia test. Further follow-up of these patients is required before a final judgement can be made as to whether more subtle but clinically relevant ACTH deficiency can be detected by the metyrapone test. Our clinical follow-up to date would not support this.

Objective: To study the reliability of the naloxone test in assessing the hypothalamic-pituitary-adrenal (HPA) axis in patients following transsphenoidal pituitary surgery, by comparison with the insulin stress test (IST). Also, to establish a normal range for the response to naloxone in healthy controls., Design: All patients had the IST performed, soluble insulin 0.1-0.3 U/kg (usually 0.15 U/kg) being administered intravenously, followed by venous sampling for plasma glucose and serum cortisol at 0, 15, 30, 45, 60, 75 and 90 minutes. Naloxone (125 micrograms/kg body weight) was similarly administered to all patients 6 days later, with sampling at -15, 0, 15, 30, 45, 60, 90 and 120 minutes for plasma glucose, serum cortisol and plasma ACTH. The naloxone test was also performed on control subjects using an identical protocol., Subjects: Twenty patients (11F/9M) aged 48.8 +/- 2.8 years (mean +/- SE) 4-6 weeks following transsphenoidal pituitary surgery. Twelve normal healthy control subjects (6F/6M) aged 31.5 +/- 3.0 years., Measurements: Serum cortisol was measured by radioimmunoassay and plasma ACTH by immunoradiometric assay., Results: Adequate hypoglycaemia (< or = 2.0 mmol/l) was achieved in all patients. Peak cortisol was > 550 nmol/l in 17 subjects (range: 572-867 nmol/l) and a subnormal response observed in 3 (peak cortisol 163-498 nmol/l). In the 17 patients with a normal cortisol response to hypoglycaemia the response to naloxone was extremely variable, with serum cortisol falling in 4 and an increment of < or = 100 nmol/l in 6 others. In the 3 patients who failed the IST, two responded to naloxone and one did not. In normal controls, 3 of the 12 had little or no response to naloxone., Conclusions: As the naloxone test fails to produce a response in all normal subjects it is impossible to define a 'normal' response. The numerous discrepancies with the IST in patients are further evidence of the test's lack of reliability in assessing the HPA-axis and it is consequently not a viable alternative to traditional dynamic methods such as the IST.

Objective: To compare the effects of monthly intra-muscular injections of a long acting preparation of octreotide, Sandostatin LAR, with multiple daily subcutaneous injections of octreotide and to study the interrelationships between mean 24 h growth hormone profile, serum total and free IGF-1 levels, 24 h urinary growth hormone levels and serum IGFBP-3., Design: Patients were assessed by 24 h GH profile off octreotide or any other GH modifying drug therapy; on subcutaneous octreotide (200-600 micrograms daily in divided doses for six weeks); and 28 days after the second of two injections of Sandostatin LAR (20 mg by intra-muscular injection) administered 28 days apart. Serum total and free IGF-1, serum IGFBP-3 and 24 h urinary GH were also measured on each occasion., Results: Sandostatin LAR was well tolerated. None of the patients reported any adverse effect and all completed the study uneventfully. Mean GH off treatment was 10.1 +/- 3.0 micrograms/l falling equally significantly (P < 0.05) during therapy with subcutaneous octreotide to 3.0 +/- 0.7 micrograms/l and Sandostatin LAR to 2.8 +/- 0.7 micrograms/l. Fasting 0900 h GH was significantly reduced (P < 0.05) on Sandostatin LAR (3.0 +/- 0.7 micrograms/l) compared with subcutaneous octreotide (5.1 +/- 1.2 micrograms/l). Mean total IGF-1 off treatment was 658.6 +/- 56.1 micrograms/l and was reduced to a comparable extent with subcutaneous octreotide and Sandostatin LAR (466.0 +/- 59.7 and 448.6 +/- 59.5 micrograms/l respectively; both P < 0.05). Free IGF-1 off treatment was 3.1 +/- 0.6 micrograms/l and was reduced equally by subcutaneous octreotide and Sandostatin LAR (1.2 +/- 0.2 and 1.2 +/- 0.2 micrograms/l; both P < 0.05). IGFBP-3 was reduced to a greater extent during Sandostatin LAR than during subcutaneous octreotide (4518.2 +/- 247.3 vs 5132.8 +/- 280.7 micrograms/l; P < 0.05). Twenty-four hour urinary GH excretion was reduced to a comparable extent with both therapies. Highly significant positive correlations were found between mean 24 h GH levels and free IGF-1 (r = 0.66, P < 0.0001) and 24 h urinary GH excretion (r = 0.94, P < 0.0001). The relationships between mean 24 h GH levels and total IGF-1 and IGFBP-3 although significant showed less powerful correlations., Conclusions: These results suggest that Sandostatin LAR is well tolerated and as effective as subcutaneous octreotide. In addition, urinary growth hormone and serum free IGF-1 may prove valuable for outpatient follow-up of acromegalic patients, as both correlate well with mean 24 h serum growth hormone levels.

Objective: Although it is well established that hypercortisolism causes insulin resistance, the mechanisms responsible for impaired insulin action in Cushing's syndrome are unclear. This study investigated the contribution of the glucose/glucose-6-phosphate substrate cycle (G/G6P)., Patients: Eight patients with Cushing's syndrome and seven control subjects were studied. All had normal fasting plasma glucose., Design: Insulin action was assessed using the euglycaemic glucose clamp at insulin infusion rates of 0.4 and 2.0 mU/kg/min combined with a simultaneous infusion of [2(3)H]- and [6(3)-H]-glucose. Glucose/ glucose-6-phosphate cycle activity was calculated as the difference in glucose turnover rates determined separately for [2(3)H]- and [6(3)H]-glucose by selective enzymatic detritiation., Measurements and Results: Exogenous glucose infusion rates required to maintain euglycaemia were significantly lower in Cushing's patients compared to controls, during the 0.4 mU/kg/min (7.8 +/- 1.2 vs 15.7 +/- 0.5 mumol/kg/min, P < 0.001) and the 2.0 mU/ kg/min insulin infusions (26.2 +/- 2.8 vs 51.5 +/- 3.5 mumol/ kg/min, P < 0.001). Endogenous glucose production was similar in both groups in the postabsorptive state (10.2 +/- 0.3 vs 10.8 +/- 0.4 mumol/kg/min, P = 0.50) and suppressed to a similar degree during hyperinsulinaemia. G/G6P cycle activity was markedly increased in the Cushing's group in the postabsorptive state (5.4 +/- 1.1 vs 2.0 +/- 0.5 mumol/kg/min, P = 0.028) and during the 0.4 mU/kg/min (3.2 +/- 0.6 vs 1.2 +/- 0.4 mumol/kg/min, P = 0.014) and 2.0 mU/kg/min insulin infusions (3.3 +/- 0.8 vs 1.1 +/- 0.5 mumol/kg/min, P = 0.049)., Conclusions: Patients with Cushing's syndrome show marked peripheral insulin resistance and enhanced hepatic G/G6P cycle activity. In the fasting state increased glucose/glucose-6-phosphate cycle activity may be a protective mechanism limiting hyperglycaemia. During hyperinsulinaemia G/G6P cycle activity was increased but insulin resistance was predominantly due to reduced peripheral glucose uptake.

Background and Objective: The differentiation of benign from malignant phaeochromocytoma is difficult. We have examined whether the use of flow cytometric determination of nuclear DNA content would be useful as a predictor of malignant behaviour in patients with phaeochromocytoma as some previous studies had suggested that a diploid cytometric DNA pattern indicated benign disease., Design and Patients: DNA flow cytometry was performed on phaeochromocytoma tissue from 36 patients (19 female, 17 male; mean age at presentation 39.5 years). The results were correlated with clinical outcome after prolonged follow-up., Measurements: DNA histograms were constructed following nuclear suspension analysis., Results: Of 26 patients followed up for more than 5 years after initial removal of primary phaeochromocytoma, three have died from malignant recurrence. In these patients a diploid DNA cytometric pattern was observed in two and an aneuploid pattern in one. Twenty-one patients are still alive. DNA cytometry showed a diploid pattern in the one patient who developed recurrent phaeochromocytoma 4 years after removal of a primary tumour., Conclusion: In this study, three of nine patients with an apparently benign diploid cytometric pattern subsequently developed recurrent disease. Routine use of DNA flow cytometry did not reliably differentiate benign from malignant phaeochromocytoma. Prolonged clinical and biochemical follow-up is still necessary for all patients with this condition.

The best long-term results of transsphenoidal surgery appear to be in those patients who have unmeasurable serum cortisol levels in the immediate post-operative period. This appears to be due to isolated ACTH deficiency in the remaining normal pituitary gland. In our experience, however, long-term clinical remission may be possible with measurable serum cortisol levels post-operatively. The cortisol response to ACTH or CRF appears to provide no greater discrimination than basal measurements and is possibly less helpful than dexamethasone suppression. The prolonged clinical remission that we have seen in some patients with early measurable but low cortisol levels, together with the possible operative morbidity and partial success of repeat surgery, suggests careful assessment before a recommendation is made of an immediate second operation in these patients. The possibility of cyclical secretion of cortisol must be considered both pre and post-operatively. Finally, as experience with transsphenoidal surgery is still relatively short, all these patients need continuing endocrine follow-up in centres with adequate experience of the condition. For the individual patient we recommend that decisions regarding further therapy are based on 0800-0900 h serum cortisol levels, an index of cortisol production (serum cortisol day profiles or 24 hour urinary free cortisol), and the response to low dose dexamethasone suppression in the early post-operative period.

We describe a case of recurrent hypoglycaemia associated with a hepatoma. During hypoglycaemia serum insulin was undetectable. Plasma insulin-like growth factor II (IGF-II) was not elevated although 71% of plasma IGF-II was present as big IGF-II (molecular weight 11 kDa) which probably represents a non-glycated form of pro-IGF-II. The GH response to hypoglycaemia was impaired and plasma levels of both IGF-I and the GH-dependent IGF binding protein (IGFBP-3) were low. A recently described unextracted assay directed against the first 21 amino acids of the E-domain (E-21) of proinsulin-like growth factor-II (pro-IGF-II) allows direct plasma estimation (plasma E-21) of larger molecular forms of IGF-II without interference from normal IGF-II and IGF binding proteins. Basal values were grossly elevated (23.7 and 23.8 nmol/l). Treatment with GH led to an increase in the mean plasma glucose across 24 hours (4.25 +/- 0.21 mol/l (mean +/- SEM) before treatment, compared with 4.86 mmol/l +/- 0.17 following GH (P < 0.01)) and a reduction in hypoglycaemic attacks. The treatment was associated with a rise in IGFBP-3 and small increases in insulin like growth factors. Subsequent treatment with the somatostatin analogue octreotide did not produce a significant change in plasma glucose levels or insulin-like growth factors. Two courses of intrahepatic adriamycin restored elevated levels of E-21 to normal. Total IGF-II remained normal and IGF-I increased. GH treatment was successfully withdrawn with no effect on plasma glucose or growth factor levels. The patient remained free from hypoglycaemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: Increasing dietary sodium intake increases blood pressure in some subjects with essential hypertension. Atrial natriuretic factor (ANF) has a potential role in modifying these changes. The purpose of this study was to observe the blood pressure and plasma ANF responses to low and high sodium diets in subjects with essential hypertension to see if the plasma ANF and blood pressure responses were related., Design: An in-patient study of subjects taking their normal diet (day 1), a 12 mmol sodium diet for 6 days and a 250 mmol diet for 6 days., Patients: Seven men with essential hypertension., Measurements: Continuous 24 hour urine collections were analysed for sodium excretion. Blood pressure was recorded at 0900, 1205 and 1700 h on days 1, 7 and 13. Blood was taken at 0900 h (fasting supine overnight) and at 1200 h (after 2 hours erect posture) on the above days for plasma ANF, plasma renin activity (PRA) and serum aldosterone., Results: Urinary sodium excretion was (mean +/- SEM) 11 +/- 1 mmol on day 5 of the low sodium diet, and 294 +/- 17 mmol during the fifth day of the high sodium diet. Plasma ANF (supine and erect) was significantly lower (2.8 +/- 0.6, 1.6 +/- 0.2 pmol/l) on the low sodium diet when compared to the high sodium diet (8.6 +/- 2.4, 5.0 +/- 1.6 pmol/l (P < 0.05)). Supine and erect PRA and serum aldosterone were significantly higher on the low compared to the high sodium diet. Blood pressure responses were heterogeneous rather than bimodal. Mean arterial blood pressure was 107 +/- 3 mmHg on the low sodium diet and 111 +/- 4 mmHg on the high sodium diet (P < 0.05). Changes of blood pressure did not correlate with the changes of plasma ANF., Conclusions: Failure of plasma atrial natriuretic factor to rise with increasing dietary sodium did not therefore determine the blood pressure response to the change in dietary sodium. No link was established between plasma atrial natriuretic factor response and sodium sensitivity.

Objective: We assessed the current role of bilateral adrenalectomy in the overall management strategy of hypercortisolism., Design: Retrospective review of case notes., Patients: Twenty-six patients (20F/6M); mean age 46 years (range 15-70 years), median duration of follow-up 5.25 years (0.6-19.1 years) who had undergone bilateral adrenalectomy at the Royal Victoria Hospital since 1972. Eighteen had had prior transsphenoidal surgery which did not control the hypercortisolism., Measurements: Morbidity, mortality, incidence of Nelson's syndrome., Results: Surgery was performed through bilateral postero-lateral incisions (20 patients) or a long epigastric incision (six patients). The mean combined weight of the adrenals at surgery was 11.2 g. Twenty patients received subcutaneous heparin and 18 antibiotic prophylaxis peri and post-operatively. There was no operative mortality. Minor complications included one post-operative wound infection and a small pneumothorax requiring drainage. Major complications occurred in two other patients, both with pre-existing invasive pituitary tumours and considered at high risk because of age and general debility. One patient had a massive pulmonary embolus and the other a subphrenic abscess post-operatively. This latter patient, the only mortality, died from an unrelated cause three years post-operatively. Six patients have subsequently undergone pituitary surgery and three have received external pituitary irradiation therapy for expanding tumours., Conclusions: Bilateral adrenalectomy, in experienced hands, is a relatively safe and useful management option in patients with hypercortisolism. Growth of a pituitary adenoma post-operatively is now the most worrying complication.

Objective: We assessed the endocrine outcome after transsphenoidal surgery for Cushing's disease., Design: Five-year (mean) follow-up (range 1 month-12 years) of patients undergoing transsphenoidal surgery for Cushing's disease between 1977 and 1990; review of case notes, current clinical and biochemical assessment including 24-hour urinary free cortisol., Setting: Northern Ireland., Subjects: Forty-one patients (33F: 8M); mean age at diagnosis 39.1 years (9-72 years)., Main Outcome Measures: Measurements of early post-operative 0800 h serum cortisol and 24-hour urinary free cortisol at least 24 hours after withdrawal of oral hydrocortisone therapy. This was followed by low dose dexamethasone testing. Current 24-hour urinary free cortisol measurements. Retrospective definition of cure., Results: Twenty-seven patients were either cured or improved by surgery, 14 were considered definite failures. Of 19 patients cured, eight had unmeasurable early post-operative 0800 h serum cortisol levels while of 15 tested, 13 had complete suppression with dexamethasone and two suppressed normally but to still measurable levels (39 and 60 nmol/l respectively). Seventeen patients in total have subsequently had bilateral adrenalectomy of whom two have developed Nelson's syndrome. Seven of the 41 patients were shown to have definite cyclical cortisol secretion first diagnosed post-operatively in three patients. Hormone deficiency included TSH (5), LH/FSH (1), cortisol (1) and ADH (temporary in 7, permanent in 1). In all, seven patients had some type of permanent hormonal deficiency post-operatively., Conclusions: Transsphenoidal surgery offers a worthwhile cure rate without the necessity of life-long endocrine therapy. Post-operative endocrine assessment must be rigorous so that early further management can be planned in the significant percentage of patients in whom cure is not achieved. Early complete suppression on low dose dexamethasone testing is very suggestive of cure but repeated and long-term monitoring of 24-hour urinary free cortisol is advisable.

Three patients were studied after transsphenoidal microsurgery for Cushing's disease because their symptoms and signs were slow to settle and/or because they had variable endocrine results. All were established as having cyclical Cushing's syndrome, first diagnosed post-operatively. This may be a much more common finding than previously realized and emphasizes the need for detailed and ongoing endocrinological investigation after transsphenoidal surgery for Cushing's disease.

Objective: We aimed to study the effect of biosynthetic growth hormone (GH) replacement in growth hormone deficient adults., Design: We performed a double-blind placebo-controlled cross-over study of 6 months biosynthetic GH, replacement and 6 months placebo separated by a 1-month's washout period., Patients: Fourteen growth hormone deficient adults were studied., Measurements: We measured total body weight, percentage fat mass, lean body mass, muscle volume, exercise capacity, maximum oxygen consumption, muscle strength, bone mineral content, a number of biochemical parameters, IGF-I, GH antibodies and psychological well-being., Results: Total body weight remained unchanged, but lean body mass increased (before GH mean +/- SEM 49.8 +/- 5.5, after 53.4 +/- 5.6 kg; placebo before 51.2 +/- 5.4, after 50.4 +/- 5.1 kg; P less than 0.05 and fat mass decreased (before GH 21.5 +/- 4.1, after 19.3 +/- 4.3; placebo before 19.3 +/- 4.0, after 22.5 +/- 4.5 kg; P less than 0.05). Thigh muscle volume increased: (before GH 94.1 +/- 7.7, after 99.5 +/- 8.4 ml; placebo before 99.3 +/- 8.6, after 95.4 +/- 7.8 ml/0.8 mm computerized tomographic slice; P less than 0.05). Exercise capacity increased (before GH 174 +/- 15, after 199 +/- 18.9 watts; placebo before 162.5 +/- 2.3, after 154 +/- 19.8 watts; P less than 0.05), as did maximum oxygen consumption (before GH 1.93 +/- 0.2, after 2.17 +/- 0.2 l/m; placebo before 1.92 +/- 0.3, after 1.98 +/- 0.2 l/m; P less than 0.05). There was no change in quadriceps muscle strength. Alkaline phosphatase increased (before GH 87.5 (32-158), after 106.0 (49-179) U/I, placebo 99.5 (50-145), after 72.0 (40-111) U/I; P less than 0.05) without a change in the spinal bone density. IGF-I increased (before GH 62 (36-97), after 216 (62-362) micrograms/l; placebo before 59 (52-112), after 60.5 (38-94) micrograms/l; P less than 0.05). Carbohydrate tolerance remained unchanged as did fasting lipids, serum sodium, potassium, urea, calcium, phosphate and liver transaminases. Psychological well-being remained unchanged. No growth hormone antibodies were detected before or after GH treatment., Conclusions: GH alters the body composition of growth hormone deficient adults and leads to improved exercise capacity; alkaline phosphatase activity increases but without a change in spinal bone density, and carbohydrate tolerance remains unaltered.

Ten acromegalic subjects were studied in a trial designed to ascertain the optimum dosage of the somatostatin analogue SMS 201-995 (octreotide) in active acromegaly. Twenty-four-hour growth hormone (GH) profiles were assessed monthly for 6 months and again after 1 year of continuous therapy. After basal assessment octreotide was administered subcutaneously at a dose of 100 micrograms three times a day throughout the first month. The dose was increased by 300 micrograms/day at monthly intervals to a maximum of 1500 micrograms/day, unless serum GH fell to within set criteria. Eight patients completed the trial. One patient withdrew because of intractable diarrhoea while another died of causes related to his acromegaly and we have no evidence that octreotide played any part in his death. Mean 24-h GH fell from a basal level of 34.3 +/- SEM 7.6 mU/l to 8.0 +/- 1.3 mU/l (P less than 0.05) after 6 months. At 1 month (300 micrograms/day) mean GH was 13.6 +/- 2.2 mU/l and at 2 months (600 micrograms/day) 10.8 +/- 2.2 mU/l (P less than 0.05 vs 300 micrograms/day dose), and at 5 months (1500 micrograms/day) 11.3 +/- 2.0 mU/l (all P less than 0.05 vs basal). Analysis of group means revealed no significant difference between any dose schedules above 600 micrograms/day. After 1 year the mean GH of the group (n = 8) was 7.5 +/- 1.3 mU/l (P less than 0.05 vs basal). Three patients developed a deterioration and one an improvement in their glucose tolerance and three developed asymptomatic gallstones during the year of therapy. In conclusion, octreotide lowered GH levels in acromegaly over a 1-year period. We found no evidence that routinely increasing the dose beyond 600 micrograms/day was helpful.

Cyproheptadine and bromocriptine have been reported to be therapeutic in suppressing ACTH levels in Cushing's disease and Nelson's syndrome. However, there have been only scattered reports of their effect in suppressing raised ACTH levels found in patients cured of Cushing's disease by bilateral adrenalectomy. In order to assess whether these agents could prove beneficial in such patients we studied 12 patients previously treated with bilateral adrenalectomy alone for Cushing's disease before and after 3 weeks of cyproheptadine and/or bromocroptine therapy. All had raised plasma ACTH values but no patient had evidence of a pituitary macroadenoma. Plasma ACTH and cortisol were sampled 2-hourly for 24 h. Neither drug regime led to any change in plasma levels of cortisol for 24 h after a 20 mg dose of oral hydrocortisone. Plasma ACTH (mean +/- SEM) showed a small but significant overall reduction (523 +/- 45 vs 392 +/- 34 ng/l; P less than 0.05) while on bromocriptine alone (5 mg given at 0800 and 1800 h, n = 5). When each time point was analysed individually this reduction was significant at only five out of 13 time points. At 0400 h plasma ACTH (mean +/- SEM) was 758.4 +/- 298.1 vs 380.2 +/- 166.6; 0600 h, 795 +/- 288.7 vs 477.8 +/- 191.7; 1200 h, 266.8 +/- 106.2 vs 187.0 +/- 80.3; 1400 h, 470.0 +/- 239.0 vs 302.0 +/- 135.9; 1600 h, 548.6 +/- 262.5 vs 394.2 +/- 178.5 ng/l (P less than 0.05). There was no significant change in plasma ACTH during treatment with the combination of bromocriptine and cyproheptadine.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of metastatic phaeochromocytoma is presented. Meta-iodobenzylguanidine was used to locate the tumour but failed to show two functioning abdominal metastatic deposits. Although meta-iodobenzylguanidine appears to be highly specific for phaeochromocytoma, a negative scan does not exclude a functioning tumour with confidence.

Six consecutive patients with Cushing's disease were treated with the broad spectrum antifungal drug ketoconazole. Urinary cortisol levels rapidly fell to within the normal range in five of the six patients. Acute hypoadrenalism occurred in one patient, and nausea and pyrexia in three. Our experience with hepatotoxicity was different from that reported by others in that reversible hepatotoxicity was demonstrated in three patients within 7 to 12 days of treatment. Further work is required before ketoconazole can be recommended as a standard primary therapy for patients with Cushing's syndrome. Continuing vigilance for both hypoadrenalism and hepatotoxicity is essential in any patient being treated with this drug either for hypercortisolism or for other reasons.

Prolactin secretion in response to TRH has been assessed in six patients with isolated gonadotrophin deficiency (IGD) and in eight normal controls. In all six subjects with IGD, serum oestradiol was below the detection limit of the method. There was no statistical difference between either the basal or maximum increment of serum prolactin between the two groups. Recent claims that prolactin responses to TRH distinguish constitutional delay of puberty from IGD have therefore not been supported.

We have studied plasma ANF before and after a 4-h intravenous infusion of normal saline in eight subjects with active acromegaly and in eight age and sex-matched control subjects. Plasma ANF, serum aldosterone and blood pressure were measured basally and after 2 and 4 h and plasma renin activity basally and after 4 h. Basal plasma ANF was similar in each group (4.4 +/- 1.5 pmol/l (mean +/- SEM) in acromegalic subjects and 5.3 +/- 0.7 pmol/l in controls NS). Plasma ANF did not rise significantly after saline in the acromegalic group (2-h value, 5.9 +/- 0.9; 4-h value, 5.1 +/- 0.9 pmol/l) but did rise significantly in the control group (2-h value, 8.9 +/- 1.9; 4-h value 9.5 +/- 1.3 pmol/l, both values P less than 0.05 vs basal level). The 4-h ANF value was significantly higher in the control group than in the acromegalic group (P less than 0.05). Basal and stimulated serum aldosterone values were similar in the two groups. Plasma renin activity suppressed to a lesser extent in the acromegalic group after 4 h. The facts that basal plasma ANF was not raised in acromegalic subjects and did not respond to saline stimulation demonstrate that an abnormality of ANF control may be an important factor in the aetiology of the expanded sodium status of patients with acromegaly and hence may contribute to the hypertension seen in patients with growth hormone excess.

Bilateral inferior petrosal sinus sampling was successfully performed in 12 of 13 consecutive patients with ACTH-dependent Cushing's syndrome. Ten of the patients subsequently had transsphenoidal pituitary microsurgery. Eight patients in whom the inferior petrosal sinus to peripheral vein ACTH level ratio was 1.5 or greater were found to have a pituitary adenoma. One of the remaining two patients who had ratios less than 1.5 had pituitary hyperplasia while the other had no identified abnormality. In five of the patients with pituitary tumour a ratio above 1.5 was present on only one side. Bilateral petrosal sampling is therefore always necessary. Tumour localization within the pituitary was only poorly predicted by either petrosal sinus sampling (four of eight) or computed tomography scanning (three of eight). If petrosal sinus sampling is used early in the differential diagnosis of ACTH-dependent hypercortisolism, then the use of other differential diagnostic tests may not always be necessary.

A patient presented with mild hyperthyroidism, elevated serum T4 and T3, and an inappropriately raised serum thyrotrophin (TSH). There was no evidence of pituitary tumour (alpha-subunit secretion and CT scan of the pituitary were normal). The TSH response to TRH was greater than normal. The elevated TSH was suppressed by oral triiodothyronine (100 micrograms daily for 10 d). The normal diurnal variation of TSH was preserved. Intravenous injection of the dopamine receptor blocking agent domperidone led to a greater than normal elevation in TSH (maximum increments 18-20 mU/l). This increased dopaminergic tone was similar in studies carried out in the morning and late evening. The dopamine agonist bromocriptine (2.5 mg twice daily) failed to suppress serum TSH either acutely or over 6 weeks. The circadian rhythm was unaltered by this treatment. Basal serum prolactin levels were normal, and responded appropriately to TRH, domperidone and bromocriptine. These observations indicate that dopamine does not control the diurnal variation of TSH in nontumoral TSH-mediated hyperthyroidism. The increased dopaminergic tone demonstrated may be secondary to the primary failure of pituitary-thyroid feedback in the condition.

A controversy still exists in regard to hypothalamic pituitary function long-term after cure of hypercortisolism due to Cushing's disease. In an attempt to resolve this controversy, we have studied 15 patients, treated at least 6 years previously, by bilateral adrenalectomy. None of these patients had had pituitary-directed therapy. The maximum increment response of serum TSH in response to TRH was greater than 5 mU/l in 13 of the 15. Serum PRL response to TRH, GH response to insulin-induced hypoglycaemia, gonadotrophin responses to LHRH and nocturnal PRL secretion were normal in all patients studied. When nocturnal GH secretion was corrected for age, body mass index and menopausal status it was definitely abnormal in only two patients. The mean nocturnal GH secretion did not differ from that measured in a control group of Addisonian patients. The series of patients also did not differ significantly from the Addisonian patients in relation to the pattern of changes in plasma ACTH, over 24 h after an 0800 h oral dose of hydrocortisone. There was a significant rise in plasma ACTH between 2200 h and 0600 h in both groups of patients. The plasma ACTH concentrations were significantly higher in post-adrenalectomy patients. Hypothalamic pituitary function is normal in the long-term in the majority of patients treated by bilateral adrenalectomy for Cushing's disease.

Spironolactone alone in full dosage failed to correct hypertension in a patient with Conn's syndrome and renal impairment, although the previously increased total exchangeable sodium fell to normal and the previously suppressed plasma angiotensin II did not rise above the normal range. Addition of the converting enzyme inhibitor captopril reduced plasma angiotensin II to very low levels, with a slight further fall in exchangeable sodium. Blood pressure was well controlled. Because hypertension in Conn's syndrome resistant to spironolactone usually also responds poorly to removal of the adenoma, and is difficult to treat with conventional hypotensive agents, the combination of a converting enzyme inhibitor with a potassium conserving diuretic is worthy of trial in such cases.

It has been suggested that the first-phase feedback of steroid feedback on ACTH secretion is abnormal in Cushing's disease patients studied after adrenalectomies. We have performed hydrocortisone infusions (100 mg over 2 h) in 15 patients who had previously undergone bilateral adrenalectomy for Cushing's disease. None had had any pituitary-directed therapy and none had a pituitary macroadenoma. Their responses were compared with a group of seven hypoadrenal patients. A significant rise in serum cortisol was observed between 5 and 10 min in both groups. The first significant fall in ACTH occurred between 30 and 45 min in both groups. There was no abnormality of first-phase feedback in the Cushing's group and our results do not therefore support previous speculation that such an abnormality provides evidence for a higher central nervous system (CNS) aetiology of Cushing's disease.

Four out of twenty-three acromegalic patients selected for treatment with external megavoltage pituitary irradiation between 1961 and 1975 developed progressive visual failure. They had received megavoltage external irradiation through multiple portals from a cobalt-60 unit over a period of 3 weeks. Visual deterioration began 2 months to 6 years after irradiation. In two patients the optic nerves were explored. In both, post-mortem later confirmed radiation damage to the optic nerves and hypothalamus. In one case there was also necrosis of the right frontal lobe with necrosis and inflammation of the bone surrounding the pituitary fossa. In the two other patients, extensive clinical and neuroradiological investigation excluded the presence of a suprasellar mass as a cause for this visual failure and a clinical diagnosis of radiation necrosis was made.

A young male patient demonstrated unusual features of Cushing's syndrome, atrial myxomas and freckled skin pigmentation. At 4.5 years of age he presented with intermittent swelling of his face and abdomen associated with weight gain and mild hypertension. A left atrial myxoma, suspected from routine physical examination, was surgically removed at 6.1 years of age. The initial mild symptoms clinically thought to be due to Cushing's syndrome, persisted intermittently without any consistent biochemical abnormality. At 10 years of age height velocity decreased and at 12 years early osteoporosis was observed radiologically. Repeated dexamethasone tests revealed a paradoxical increase in cortisol and corticotrophin from normal basal levels. Further investigation showed a cyclical pattern of hypercortisolism. The removal of a pituitary microadenoma failed to correct the features of Cushing's syndrome or prevent intermittent hypercortisolism. At 15.3 years a second left atrial myxoma was removed. This was followed by bilateral adrenalectomy. Histologically the features were consistent with primary pigmented nodular adrenocortical disease. This is the first patient described with cyclical Cushing's syndrome as part of this unusual complex of disorders.

An 11-year-old male presented with a 2-year history of headache and lethargy. Serum PRL was elevated at 14,000 mU/l and computerized tomography showed a pituitary macroadenoma. Visual fields and fundi were normal and the testes showed early pubertal changes. There was normal responsiveness of serum cortisol but absence of GH response to hypoglycaemia. After bromocriptine therapy for 4 months serum PRL had fallen to 90 mU/l and the tumour was not visible on repeat computerized tomography. After 7 months treatment, repeat pituitary function testing showed restoration of GH response to hypoglycaemia. Treatment with bromocriptine was continued and there was spontaneous progression of normal puberty; the serum testosterone continued to rise, and height maintained the 50th centile. Bromocriptine therapy should be considered as initial therapy in the management of prolactinomas in prepubertal patients.