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Biomedical subjects

John P Monson

Publications and source records attributed to John P Monson.

At least 19 recordsLinked to original sources
PubMed2007

Growth hormone (GH) replacement therapy in GH deficient adults: predictors of one-year metabolic and clinical response.

OBJECTIVE: This study investigated whether baseline status could predict the responsiveness to one-year growth hormone (GH) replacement therapy in adult GH deficient (GHD) patients. DESIGN: A total of 380 European patients with adult onset GHD due to non-functioning pituitary adenoma that had been enrolled in Pfizer International Metabolic Database (KIMS), and that had completed one year of GH replacement therapy within KIMS, were studied. RESULTS: The mean initial dose of GH was 0.22 (SEM 0.01) mg/day and after one year, the mean dose was 0.36 (0.01) mg/day. The mean insulin-like growth factor-I (IGF-I) SD score increased from -1.75 (0.08) at baseline to 0.47 (0.05) after one year. Quality of life (QoL)-Assessment of GHD in Adults (QoL-AGHDA), waist circumference, waist:hip ratio, and serum lipid pattern improved. Women received a higher dose of GH than men after one year, and demonstrated similar treatment response. In multiple stepwise forward regression analyses, the one-year changes in QoL-AGHDA score, waist:hip ratio, and serum low density lipoprotein-cholesterol (LDL-C) level correlated inversely with the baseline values of the same variable. In addition, the change after one year in QoL-AGHDA score correlated inversely with duration of hypopituitarism and baseline serum high density lipoprotein-cholesterol (HDL-C) level, and the change in waist:hip ratio correlated inversely, although more weakly, with baseline serum HDL-C level and UK citizenship and positively with baseline waist circumference and the initial GH dose. The change in serum LDL-C level additionally correlated inversely with the mean GH dose and duration of hypopituitarism and positively with UK citizenship. CONCLUSIONS: Baseline status could, with moderate strength, predict the responsiveness in the same variable whereas it could not, or only weakly, predict the response in other variables. Therefore, when the decision to start GH replacement is undertaken, as many outcome variables as possible should be evaluated in order to adequately evaluate the likelihood of clinical benefit. Finally, women have a similar response to GH replacement as men when individualised GH dosing schedules are employed and should therefore be selected for GH therapy to a similar extent.

Cohort Studies↗
PubMed2007

Unmasking of central hypothyroidism following growth hormone replacement in adult hypopituitary patients.

BACKGROUND: The effect of GH replacement on thyroid function in hypopituitary patients has hitherto been studied in small groups of children and adults with conflicting results. OBJECTIVE: We aimed to define the effect and clinical significance of adult GH replacement on thyroid status in a large cohort of GH-deficient patients. PATIENTS AND METHOD: We studied 243 patients with severe GH deficiency due to various hypothalamo-pituitary disorders. Before GH treatment, 159 patients had treated central hypothyroidism (treated group) while 84 patients were considered euthyroid (untreated group). GH dose was titrated over 3 months to achieve serum IGF-1 concentration in the upper half of the age-adjusted normal range. Serial measurements of serum T4, T3, TSH and quality of life were made at baseline and at 3 and 6 months after commencing GH replacement. RESULTS: In the untreated group, we observed a significant reduction in serum T4 concentration without a significant increase in serum T3 or TSH concentration; 30/84 patients (36%) became hypothyroid and needed initiation of T4 therapy. Similar but lesser changes were seen in the treated group, 25 of whom (16%) required an increase in T4 dose. Patients who became hypothyroid after GH replacement had lower baseline serum T4 concentration, were more likely to have multiple pituitary hormone deficiencies and showed less improvement in quality of life compared with patients who remained euthyroid. CONCLUSION: GH deficiency masks central hypothyroidism in a significant proportion of hypopituitary patients and this is exposed after GH replacement. We recommend that hypopituitary patients with GH deficiency and low normal serum T4 concentration should be considered for T4 replacement prior to commencement of GH in order to provide a robust baseline from which to judge the clinical effects of GH replacement.

Adolescent↗
PubMed2006

The impact of glucocorticoid replacement regimens on metabolic outcome and comorbidity in hypopituitary patients.

BACKGROUND: Hypopituitary patients with untreated GH deficiency and patients on inappropriately high doses of glucocorticoid (GC) share certain clinical features. OBJECTIVE: The aim of the study was to examine the influence of GC substitution on clinical characteristics in hypopituitary patients before and after GH replacement therapy. METHOD: A total of 2424 hypopituitary patients within the KIMS (Pfizer International Metabolic Database) were grouped according to ACTH status. Comparisons were performed between subjects on hydrocortisone (HC) (n = 1186), cortisone acetate (CA) (n = 487), and prednisolone/dexamethasone (n = 52), and ACTH-sufficient patients (AS) (n = 717) before and after 1 yr of GH treatment in terms of body mass index, waist and hip circumference, blood pressure, glucose, glycosylated hemoglobin (HbA1c), serum lipids, IGF-I, and comorbidity. Hydrocortisone equivalent (HCeq) doses were calculated, and measurements were adjusted for sex and age. RESULTS: At baseline, the HC group had increased total cholesterol, triglycerides, waist circumference, and HbA1c, and the prednisolone/dexamethasone group had increased waist/hip ratio as compared with AS. After HCeq dose adjustment, the HC group retained higher HbA1c than the CA group. GC-treated patients showed a dose-related increase in serum IGF-I, body mass index, triglycerides, low-density lipoprotein cholesterol and total cholesterol levels. Subjects with HCeq doses less than 20 mg/d (n = 328) at baseline did not differ from AS in metabolic endpoints. The 1-yr metabolic response to GH was similar in all GC groups and dose categories. All new cases of diabetes (n = 12), stroke (n = 8), and myocardial infarction (n = 3) during GH treatment occurred in GC-treated subjects. CONCLUSION: HCeq doses of at least 20 mg/d in adults with hypopituitarism are associated with an unfavorable metabolic profile. CA replacement may have metabolic advantages compared with other GCs.

Adrenocorticotropic Hormone↗
PubMed2006

Dehydroepiandrosterone improves psychological well-being in male and female hypopituitary patients on maintenance growth hormone replacement.

CONTEXT: Patients with panhypopituitarism have impaired quality of life (QoL) despite GH replacement. They are profoundly androgen deficient, and dehydroepiandrosterone (DHEA) has been shown to have a beneficial effect on well-being and mood in patients with adrenal failure and possibly in hypopituitarism. OBJECTIVE: Our objective was to determine the effect of DHEA administration on mood in hypopituitary adults on established GH replacement with a constant serum IGF-I. DESIGN: A double-blind, placebo-controlled trial was conducted over an initial 6 months followed by an open phase of 6 months of DHEA. SETTING: The study was conducted at a tertiary referral endocrinology unit. PATIENTS: Thirty female and 21 male hypopituitary patients enrolled. Data from 26 females and 18 males were analyzed after patient withdrawal. INTERVENTIONS: DHEA (50 mg) was added to maintenance replacement including GH. MAIN OUTCOME MEASURES: The primary outcome objective was the effect on QoL and libido assessed by QoL assessment in GH deficiency in adults, Short Form 36, General Health Questionnaire, EuroQol, and sexual self-efficacy scale. RESULTS: Patients had impaired QoL at baseline compared with the age-matched British population. Females showed improvement in QoL assessment in GH deficiency in adults score (-2.9 +/- 2.8 DHEA vs.-0.53 +/- 3 placebo; P < 0.05), in Short Form 36 social functioning (14.6 +/- 23.1 DHEA vs.-4.7 +/- 25 placebo; P = 0.047), and general health perception (9.6 +/- 14.2 DHEA vs.-1.2 +/- 11.6 placebo; P = 0.036) after 6 months of DHEA. Men showed improvement in self-esteem (-1.3 +/- 1.7 DHEA vs. 0.5 +/- 1.5 placebo; P = 0.03) and depression (-1.6 +/- 2.2 DHEA vs. 1.2 +/- 2.4 placebo, P = 0.02) domains of the General Health Questionnaire after 6 months of DHEA. CONCLUSIONS: DHEA replacement leads to modest improvement in psychological well-being in female and minor psychological improvement in male hypopituitary patients on GH replacement.

Dehydroepiandrosterone↗
PubMed2006

The management of differentiated thyroid cancer using 123I for imaging to assess the need for 131I therapy.

BACKGROUND: Follow-up of 131I whole-body scanning after 131I ablation is associated with potential stunning. Previous studies have suggested that, for scanning, 123I is more sensitive than 131I in identifying thyroid tissue, but its specificity when positive is less certain. AIM: The use of 123I as an imaging agent in place of serial 131I imaging has been evaluated in the surveillance and treatment of differentiated thyroid carcinoma. RESULTS: A total of 186 studies in 136 patients with differentiated thyroid carcinoma were evaluated after total or near total thyroidectomy followed by 131I ablation. In 125 studies 123I scanning was negative and no 131I therapy was given; four patients were positive on 123I scanning but for other reasons no 131I therapy was given. In 48/49 patients a positive 123I scan was followed by positive 131I therapeutic uptake. Only one patient failed to show positive uptake of I when first treated and she subsequently demonstrated uptake on a second therapy. CONCLUSION: High-dose 123I imaging is the correct predictor of the 131I post-therapy scan findings in most cases, at an administered activity that avoids stunning. As a diagnostic agent it is preferable to 131I in differentiated thyroid carcinoma.

Adolescent↗
PubMed2006

Dehydroepiandrosterone (DHEA) replacement reduces growth hormone (GH) dose requirement in female hypopituitary patients on GH replacement.

OBJECTIVE: GH dose requirement is lower in ACTH replete compared with ACTH deficient hypopituitary patients suggesting that adrenal androgens may augment IGF-I generation for a given GH dose. This study aimed to determine the effect of dehydroepiandrosterone (DHEA) administration on GH dose requirements in hypopituitary adults. DESIGN: A double blind placebo controlled trial was conducted adding 50 mg DHEA to the standard replacement of hypopituitary patients, including GH, over an initial 6 months, followed by an open phase study of 6 months DHEA replacement and a final 2 month washout phase after DHEA withdrawal. The dose of GH was adjusted to achieve a constant serum IGF-I. PATIENTS: Thirty female and 21 male hypopituitary patients were enrolled. Data from 26 women and 18 men were analysed after patient withdrawal. MEASUREMENTS: The primary outcome objective was the GH dose required to achieve a stable serum IGF-I. Secondary outcome measures were lipoprotein profiles, insulin, insulin sensitivity, IGFBP-3, waist/hip ratio and indices of bone remodelling. RESULTS: DHEA replacement in female patients lead to a 14.6 +/- 20% reduction in the dose of GH for a constant serum IGF-I (P < 0.05, 95% CI: 1.8, 32.7). This was maintained for 12 months and there was a significant fall in serum IGF-I two months after withdrawal of DHEA. There was no change in the male group. CONCLUSIONS: DHEA replacement may reduce GH dose requirements in female hypopituitary patients.

Adult↗
PubMed2006

Is there still a role for radiotherapy in acromegaly?

External radiotherapy (ideally 3-field radiotherapy with a daily fractional dose no higher than 1.8 Gy or conformal irradiation) has been used extensively in the treatment of acromegaly, and virtually all studies have documented a predictable but slow reduction in growth hormone (GH) excess, which is at its maximum in the first year after treatment (30-50%) and continues at an average rate of 10-15% thereafter in the long term. Therefore, achievement of 'safe' GH concentrations in an acceptable time interval after radiotherapy will be realized only in those patients who have lower GH concentrations prior to irradiation either as a result of mild disease or previous surgery. Recent studies have demonstrated the value of stereotactic radiotherapy (either as multiple arc X-irradiation or as 'gamma knife' therapy) in the post-surgical treatment of acromegaly or as salvage therapy for disease persisting after conventional external irradiation. The development of potent medical therapies for acromegaly (somatostatin analogues and the GH receptor antagonist) has called into question the role of radiotherapy in the treatment of this disease. However, even if the concept of primary, open-ended medical therapy for selected patients is accepted, reference to the success rates of surgery and response rates to somatostatin analogues indicates that approximately 10-20% of all patients with acromegaly will require consideration of radiotherapy for hormonal or tumour mass control. For these reasons, radiotherapy (both conventional external and stereotactic irradiation) continues to have a major role in controlling acromegaly in selected patients.

Acromegaly↗
PubMed2006

Does long-term GH replacement therapy in hypopituitary adults with GH deficiency normalise quality of life?

OBJECTIVE: To determine whether impaired quality of life (QoL) in adults with GH deficiency (GHD) is reversible with long-term GH therapy and whether the responses in QoL dimensions differ from each other. METHODS: QoL was measured by the Quality of Life-Assessment for Growth Hormone Deficiency in Adults (QoL-AGHDA) in general population samples in England & Wales, The Netherlands, Spain and Sweden (n = 892, 1038, 868 and 1682 respectively) and compared with corresponding patients' data from KIMS (Pfizer International Metabolic Database) (n = 758, 247, 197 and 484 respectively) for 4-6 years a follow-up. The subsets of patients from England and Wales, and Sweden with longitudinal data for 5 years' follow-up were also analysed. The change of the total QoL-AGHDA scores and responses within dimensions were evaluated. Subanalyses were performed to identify any specificity in response pattern for gender, age, disease-onset and aetiology. RESULTS: Irrespective of the degree of impairment, overall QoL improved dramatically in the first 12 months, with steady progress thereafter towards the country-specific population mean. Problems with memory and tiredness were the most serious burden for untreated patients, followed by tenseness, self-confidence and problems with socialising. With treatment, these improved in the reverse order, normalising for the latter three. CONCLUSIONS: Long-term GH replacement results in sustained improvements towards the normative country-specific values in overall QoL and in most impaired dimensions. The lasting improvement and almost identical pattern of response in each patient subgroup and independent of the level of QoL impairment support the hypothesis that GHD may cause these patients' psychological problems.

Adult↗
PubMed2006

Determinants of cardiovascular risk in 2589 hypopituitary GH-deficient adults - a KIMS database analysis.

OBJECTIVE: The aim of the present study was to clarify the relationship between GH deficiency (GHD) and some cardiovascular risk factors and to analyse the effect of GH replacement therapy in a large number of patients over a prolonged period of time. DESIGN: Data for analysis were retrieved from KIMS (Pfizer International Metabolic Database). Serum concentrations of total cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides were obtained from 2589 patients at baseline and from 1206 patients after 1 and 2 years of GH replacement therapy. Body mass index (BMI), waist and hip, resting blood pressure and body composition were also measured. RESULTS: At baseline, the unfavourable effects of GHD were most obvious in the lipid profile demonstrating elevated mean total and LDL-cholesterol, in the increased waist circumference and the elevated BMI. The cholesterol concentration, BMI and body composition were significantly adversely affected by a number of factors, including age, sex and the use of anti-epileptic drugs. The therapeutic effect of GH was essentially uniform across the whole population. GH replacement reduced significantly the mean total and LDL-cholesterol, the waist circumference and the fat mass and was maintained during 2 years. CONCLUSIONS: This analysis of a large number of patients confirmed that GHD adults present with an increased cardiovascular risk. The sustained improvement of the adverse lipid profile and body composition suggests that GH replacement therapy may reduce the risk of cardiovascular disease and the premature mortality seen in hypopituitary patients with untreated GHD.

Adult↗
PubMed2005

The ectopic adrenocorticotropin syndrome: clinical features, diagnosis, management, and long-term follow-up.

CONTEXT: There are few large series of patients with ectopic, nonpituitary, corticotropin (ACTH) secretion (EAS). OBJECTIVE: The objective of this study was to analyze the clinical, biochemical, and radiological features, management, and treatment outcome of patients with EAS. DESIGN: This was a retrospective case-record study. SETTING: The setting for this study was a tertiary referral hospital center. PATIENTS: Forty patients with EAS were studied. MAIN OUTCOME MEASURES: Clinical, biochemical, and radiological features and response to therapy and survival were measured. RESULTS: The median follow-up was 5 yr (range, 2-30 yr). None of the dynamic tests achieved 100% accuracy, but bilateral inferior petrosal sinus sampling showed an absent central gradient in all but one case (one of 12). Imaging correctly identified the lesion at first investigation in 65% of cases. Bronchial carcinoid tumors were the most common cause of EAS (n = 12; 30%), followed by other neuroendocrine tumors (n = 13, 32.5%). In 12.5% of patients, the source of EAS was never found. Octreotide scintigraphy and whole-body venous sampling were of limited value. Surgical attempt at curative resection was successful in 83% (10 of 12) of patients with bronchial carcinoid tumors; others responded generally well to adrenolytic therapy or bilateral adrenalectomy. Tumor histology and the presence of distant metastases were the main predictors of overall survival (P < 0.05). CONCLUSIONS: A variety of tests and imaging studies are necessary for the correct diagnosis of the EAS, but even then, up to 20% of cases present a covert or occult EAS syndrome. These cases require a prolonged follow-up, review, and repetition of diagnostic tests and scans.

ACTH Syndrome, Ectopic↗
PubMed2005

Quality of life assessment of growth hormone deficiency in adults (QoL-AGHDA): comparison of normative reference data for the general population of England and Wales with results for adult hypopituitary patients with growth hormone deficiency.

BACKGROUND/AIM: Age- and gender-specific reference values for the quality of life (QoL) measures used in assessing the impact of growth hormone deficiency (GHD) are important. The objective of this study was to develop such data for the QoL-AGHDA instrument for the population of England and Wales and to demonstrate the QoL deficit in patients with GHD. METHODS: For the purpose of this study, a questionnaire was developed that contained the EurQoL EQ-5D, QoL-AGHDA, questions recording an individual's general situation and social functioning, and a self-reported five-point rating scale of general health. The questionnaire was mailed out to a sample of 1,190 individuals drawn from the general population of England and Wales. Corresponding data for 836 patients were retrieved from KIMS (Pfizer International Metabolic Database). The postal survey data were weighted to ensure that they were representative of the general population. RESULTS: The mean weighted QoL-AGHDA scores for the general population were 6.2 and 7.1 for men and women, respectively, compared with 13.6 and 15.7 for patients. For both males and females the differences in mean QoL-AGHDA scores between the general population and patients were statistically significant for all age categories (p < 0.01). In the general population the mean QoL-AGHDA score for each category of self-assessed health status increased progressively, indicating a poorer QoL as health status declined. CONCLUSIONS: This study reports QoL-AGHDA normative values for the population of England and Wales and confirms the extent of QoL impairment in patients with GHD in comparison with the general population.

Adult↗
PubMed2005

Clinical and biochemical characteristics of adrenocorticotropin-secreting macroadenomas.

CONTEXT: Cushing's disease as a result of a pituitary macroadenoma is an uncommon cause of Cushing's syndrome, and reports in the published literature are few and of limited size. OBJECTIVE: Our objective was to establish the clinical and biochemical characteristics of macroadenomas associated with Cushing's disease compared with a large cohort of microadenomas and to assess their response to therapy. DESIGN: We conducted a retrospective case-records study for the years 1964-2001. SETTING: The study occurred at a tertiary referral hospital center. PATIENTS: Patients had Cushing's disease presenting with a pituitary macroadenoma, in comparison with a large group of microadenoma patients. INTERVENTIONS: Interventions included therapy with surgery and radiotherapy. MAIN OUTCOME MEASURES: Outcome measures included basal and dynamically responsive plasma ACTH and cortisol levels and response to treatment. RESULTS: We identified 18 patients with Cushing's disease secondary to a macroadenoma; basal 0900 h plasma ACTH was 135.8 +/- 32.5 and 45.0 +/- 4.3 ng/liter (mean +/- SEM), respectively, in macroadenomas and microadenomas (P = 0.013). Mean 0900 h serum cortisol was significantly increased in the macroadenomas (27.5 +/- 3.0 microg/dl, 759.6 +/- 82.6 nmol/liter, vs. 22.6 +/- 0.6 microg/dl, 624.7 +/- 16.4 nmol/liter) (P = 0.021). Testing with high-dose dexamethasone showed less suppression in the macroadenomas (57.6 +/- 8.7% vs. 74.4 +/- 2.1%; P = 0.02) and an attenuated ACTH response to CRH. For all biochemical variables there was considerable overlap between the two groups. Few patients with macroadenomas were cured by surgery. CONCLUSIONS: Pituitary macroadenomas causing Cushing's disease have biochemical features largely distinct from patients harboring microadenomas but represent one end of a continuum.

Adenoma↗
PubMed2005

A rapid method for analyzing serum pro-insulin-like growth factor-II in patients with non-islet cell tumor hypoglycemia.

CONTEXT: Non-islet cell tumor hypoglycemia (NICTH) results from the hypersecretion of pro-IGF-II by a large, usually mesenchymal tumor. Detection of pro-IGF-II in serum is a potential tumor marker in these patients. OBJECTIVE: The aim of this study was to validate a rapid and reliable method for determining serum pro-IGF-II. PATIENTS: Serum samples from 16 patients with NICTH were studied. MAIN OUTCOME MEASURE: The main outcome measure was serum concentration of pro-IGF-II determined by immunoblot analysis of pro-IGF-II and mature IGF-II after 16.5% tricine-SDS-PAGE, which was compared with pro-IGF-II measured by standard RIA after size-exclusion acid chromatography. RESULTS: The analyses of patients' sera by size-exclusion acid chromatography showed that 68 +/- 19% of IGF-II were present in the pro-IGF-II form, whereas only 18 +/- 4% corresponded to pro-IGF-II in controls. Scanning densitometry of immunoblots showed 67 +/- 16% in the bands corresponding to pro-IGF-II in patients' sera, compared with 27 +/- 9% in controls. The detection sensitivity of tricine-SDS-PAGE method was the same as for size-exclusion chromatography, but the tricine-SDS-PAGE method is quicker and requires smaller amounts of serum. CONCLUSION: Tricine-SDS-PAGE followed by IGF-II immunoblot analysis provides a rapid, reproducible, and sensitive method for the separation of serum pro-IGF-II from mature IGF-II and is a useful laboratory evaluation of patients with a clinical diagnosis of NICTH.

Adult↗
PubMed2005

Isolated growth hormone (GH) deficiency in adult patients: baseline clinical characteristics and responses to GH replacement in comparison with hypopituitary patients. A sub-analysis of the KIMS database.

BACKGROUND: Isolated growth hormone deficiency (IGHD) provides the ideal model to characterize GHD without interference from other pituitary deficiencies or their treatment. No study has addressed the question whether adult patients with IGHD differ in clinical presentation or in responsiveness to GH replacement from adult patients with multiple pituitary hormone deficiencies (MPHD) receiving conventional replacement therapy. PATIENTS AND METHODS: Data were retrieved from the outcomes research database KIMS (Pfizer international metabolic database). Patients with IGHD accounted for 9.6% (274/2868) of all GHD patients. Patients were separated according to the timing of onset. In the adult-onset (AO) group, 167 patients with IGHD were compared to 1992 patients with MPHD. In the childhood-onset (CO) group, 107 patients with IGHD were compared to 602 patients with MPHD. To assess the effect of GH replacement after one year, a longitudinal sub-analysis in the AO group was performed comparing 89 IGHD patients to 1234 MPHD patients. The same study was done in the CO group comparing 66 IGHD patients to 386 MPHD patients. Because IGHD patients were significantly younger than MPHD patients, data analysis was also performed after adjustment for gender and age. RESULTS: In the AO group, non-functioning and secreting pituitary adenomas were the most common primary diagnoses in both IGHD and MPHD. Medical history revealed a high prevalence of hypertension and fractures in both subgroups, but also of non-insulin dependent diabetes mellitus. The prevalence of obesity was high and the waist circumference was elevated. The lipid profile was unfavourable in both IGHD and MPHD. IGF-I concentration and SDS were comparable in both subgroup. Quality of life assessed by QoL-AGHDA was equally poor in both IGHD and MPHD. GH replacement therapy induced favourable changes without distinction. In the CO group, the most common cause in both subgroups was idiopathic. Fracture rate was similarly prevalent in both IGHD and MPHD. Obesity was prominent in both subgroups, but BMI and waist circumference were lower in IGHD. Adverse lipid changes were similarly found in both IGHD and MPHD. IGF-I concentration and SDS were significantly higher in the IGHD subgroup compared to the MPHD subgroup. The QoL-AGHDA score was equally abnormal in both IGHD and MPHD. GH replacement achieved similar significant improvement in both subgroups. CONCLUSIONS: GHD patients with AO-IGHD and AO-MPHD present with a similar clinical expression and respond similarly to GH replacement. Patients with CO-IGHD are less severely affected by GHD than CO-MPHD patients, but, nevertheless, both groups show a comparable adverse lipid profile and poor quality of life and respond favourably to GH replacement. These findings support the concept that GH alone is responsible for most if not all metabolic aspects of hypopituitary patients receiving conventional replacement therapy, regardless of age of onset or aetiology. As a consequence, GH replacement therapy not only has potential benefit in GHD patients with additional hormonal deficits, but also the indication of treatment must be extended to patients with isolated GHD.

Adenoma↗
PubMed2005

Monitoring of insulin-like growth factors during growth hormone treatment: adulthood growth hormone deficiency.

Decisions on growth hormone (GH) dosing in paediatric practice have depended on body weight or surface area calculations. Although this policy was used initially in the treatment of adult patients, it has become apparent both in clinical studies and longitudinal observation that this results in relative overtreatment of male patients, with a high incidence of immediate side effects, and undertreatment of females. Use of individualized GH dosing against serum IGF-I has proven useful in optimizing therapy across the whole adult age range, including the elderly and in patients who are in transition from post-puberty to full somatic development. It also eliminates gender differences in susceptibility. In this respect, serum IGF-I is superior to other GH-dependent peptides. However, on present evidence, serum IGF-I should be regarded primarily as a safety marker rather than a specific therapeutic marker.

Adult↗
PubMed2005

Factors influencing cure by transsphenoidal selective adenomectomy in paediatric Cushing's disease.

OBJECTIVE: Early diagnosis and effective treatment of paediatric Cushing's disease (CD) is necessary to minimise associated morbidity. Accepted first-line treatment is selective transsphenoidal microadenomectomy (TSS), which can be technically difficult, and cure rates vary considerably between centres. In our paediatric CD patient group we have assessed the possible factors which may influence cure by TSS. SUBJECTS AND METHODS: From 1983-2004, 27 paediatric patients (16 males, 11 females; mean age+/-s.d., 13.1+/-3.2 yr; range, 6.4-17.8 yr) with CD were managed in our centre and underwent TSS. Sixteen patients (59%), seven males and nine females (mean age+/-s.d., 14.2+/-2.5 yr; range, 8.2-17.8 yr), were cured (post-operative serum cortisol < 50 nM). Eleven patients, nine males and two females (mean age+/-s.d., 11.5+/-3.6 yr; range, 6.4-17.8 yr) had post-operative cortisol levels above 50 nM (2-20 days), with mean serum cortisol levels at 09:00 h of 537 nM (range 269-900 nM) indicating a lack of cure. These 11 patients received external beam pituitary radiotherapy (RT). One patient with a pituitary macroadenoma had a post-operative cortisol level of < 50 nM but 0.8 yr later showed an elevated cortisol and residual disease. RESULTS: The patients cured by TSS alone were significantly older than those not cured (P = 0.038; Student's t test). All patients had CT/MRI pituitary imaging: 14 were reported to have microadenomas and one macroadenoma, while 12 were reported as normal. Bilateral simultaneous inferior petrosal sinus sampling (BSIPSS) with i.v. corticotropin-releasing hormone (CRH) administration was introduced as a pre-operative investigation in 1986 and was performed in 21 patients (78%), on BSIPSS, 16 (76%) had evidence suggesting pituitary adrenocorticotropic hormone (ACTH) secretion (central to peripheral (IPS:P) ACTH ratio after CRH of > or = 3.0) and 16 (76%) showed lateralisation of ACTH secretion (IPSG of > or = 1.4). There was concordance between the BSIPSS finding and the position of the microadenoma at surgery in 17/21 (81%) patients. Of the 16 patients showing lateralisation of ACTH secretion, 12 (75%) were cured by TSS. Of the four without lateralisation of ACTH, suggesting a midline lesion, 3 (75%) were cured by TSS. Post-operative pituitary hormone deficiencies in the patients cured by TSS were: pan-hypopituitarism 1/16, isolated growth hormone deficiency (GHD) (peak GH on glucagon/ITT < 1-17.9 mU/l) 9/16 and diabetes insipidus 3/16. CONCLUSION: Over a 21-year period selective adenomectomy by TSS cured 59% of all paediatric CD patients, with higher age favouring cure. Introduction of BSIPSS resulted in the demonstration of a high rate of lateralisation of ACTH secretion consistent with the surgical identification of the adenoma, and therefore appears likely to have contributed to the higher surgical cure rate.

Adenoma↗
PubMed2004

CT and MR imaging of unusual locations of extra-adrenal paragangliomas (pheochromocytomas).

Our review was undertaken to describe CT and MRI features of unusual extra-adrenal paragangliomas (pheochromocytomas). We retrospectively reviewed CT and MRI findings in 29 patients with 39 extra-adrenal paragangliomas. For each tumour, site, size, MRI characteristics, CT appearances and enhancement after gadolinium and iohexol were recorded. There were 17 carotid body tumours, 1 mediastinal, 1 intra-cardiac, 15 retroperitoneal extra-adrenal paragangliomas, 2 bladder, 1 pelvic sidewall and 2 intra-spinal paragangliomas within the lumbo-sacral spine. All 39 paragangliomas were shown on MRI. Of the 32 lesions studied by MRI and CT, CT detected 30. Of the two lesions missed on CT, one was an intra-cardiac paraganglioma and the second a bladder wall paraganglioma. At detection, 25 tumours were larger than 4 cm, of which 20 were heterogeneous lesions on CT and MRI with variable contrast enhancement. The 14 smaller paragangliomas were smooth in contour and demonstrated avid, homogeneous contrast enhancement. Our review of extra-adrenal paragangliomas highlights their unusual sites and appearances. MRI demonstrated the greatest variability in the appearances of larger tumours, provided additional information compared to CT for surgical planning and is a useful screening tool for patients at high risk of extra-adrenal paragangliomas.

Adult↗