[Growth hormone in the elderly man]

Many symptoms being part of the growth hormone deficiency syndrome in adults like decrease in muscle mass and bone mineral content, increase in fat mass, and skin atrophy are observed also with ageing. Indeed, short term trials with growth hormone administration to persons over 60 years old revealed that many of these symptoms could be reversed by growth hormone. However, recent reports of an association of high insulin-like growth factor-1 (IGF-1)-concentrations and increased risk of prostate, lung, colon and breast cancer as well as a possible decrease of insulin sensitivity prohibit currently the use of growth hormone in an attempt to reverse a normal ageing process. Prospective, randomised and placebo-controlled long-term trials are necessary to prove safety and efficacy of growth hormone therapy in the ageing population before it can be recommended. In addition, no data are available as to the right growth hormone dose and the correct monitoring. Expectations of the society and the search for the fountain of youth should not motivate physicians to leave the firm ground of evidence based medicine and prescribe experimental therapies to healthy older persons.

Differential effects of growth hormone therapy in malnourished hemodialysis patients

BACKGROUND

Malnutrition is common in chronic hemodialysis patients and is associated with increased morbidity and mortality. Several factors such as metabolic acidosis, hyperparathyroidism, and insulin as well as growth hormone (GH) resistance may lead to enhanced protein catabolism. Recombinant human growth hormone (rhGH) has been proposed as treatment of malnutrition because of its anabolic effects.

METHODS

In the present placebo-controlled, double blind study, the effects of three months of rhGH therapy on nutritional and anthropometric parameters, on bone metabolism and bone mineral density (BMD), as well as on polymorphonuclear leukocyte (PMNL) function and quality of life (QoL) were evaluated in 19 malnourished hemodialysis patients (10 females and 9 males) with a mean age of 59.3 +/- 13.4 years. RhGH (0.125 IU/kg) was given three times a week during the first four weeks and 0.25 IU/kg thereafter three times a week after each dialysis session.

RESULTS

Insulin-like growth factor I (IGF-I) concentration rose significantly from 169.2 +/- 95.6 ng/mL to 262.9 +/- 144.4 ng/mL (p< 0.01) in the group receiving rhGH. Albumin, prealbumin, transferrin, cholesterol, high-density lipoprotein (HDL) cholesterol, cholinesterase, predialytic creatinine, and blood urea nitrogen showed no significant changes during the three months in both groups. Total body fat (%TBF) was slightly reduced after three months (P = NS) in the patients receiving GH, whereas lean body mass (LBM) remained stable during therapy. Procollagen I carboxy terminal peptide (PICP), a marker of bone formation, increased significantly after three months from 250.1 +/- 112.6 to 478.5 +/- 235.2 microg/L (P < 0.01) in the GH-treated patients, whereas parameters of bone resorption like telopeptide ICTP showed only a slight increase (50.3 +/- 18.5 vs. 70.0 +/- 39.5 microg/L, P = NS). BMD at the lumbar spine decreased significantly after three months in the treatment group (0.8 +/- 0.17 vs. 0.77 +/- 0.16 g/cm2, P < 0.01), whereas BMD at the femoral neck remained stable in both groups. Phagocytic activity of PMNLs increased significantly after three months of therapy with rhGH, whereas other parameters of PMNL function were not affected by GH. QoL was slightly improved in the GH treated group, but decreased markedly in the placebo group.

CONCLUSIONS

Three months of treatment with rhGH in malnourished patients on chronic hemodialysis causes a significant increase in IGF-I levels without significant changes in nutritional and anthropometric parameters. In contrast, bone turnover was enhanced with an initial decrease in BMD at the lumbar spine, and phagocytic activity of PMNLs was increased.

Apoplexy of a pituitary macroadenoma with reversible third, fourth and sixth cranial nerve palsies following administration of hypothalamic releasing hormones: MR features

Pituitary apoplexy in patients with pituitary macroadenomas can occur either spontaneously or following various interventions. We present a case of a 71-year-old woman who developed third, fourth, and sixth cranial nerve palsies following administration of the four hypothalamic releasing hormones for routine preoperative testing of pituitary function. The MR examination showed interval tumor growth with impression of the floor of the third ventricle. There were also changes in signal intensity characteristics of the mass, suggestive of intratumoral bleeding. A transsphenoidal surgery with subtotal resection of the pituitary adenoma was performed. Microscopical examination revealed large areas of necrosis and blood surrounded by adenomatous tissue. Third, fourth, and sixth cranial nerve palsies completely resolved within 4 months. We conclude that MR imaging is useful in the demonstration of pituitary apoplexy following preoperative stimulation tests, but we suggest that these tests should be abandoned in patients with pituitary macroadenomas.

The increased insulin sensitivity in growth hormone-deficient adults is reduced by growth hormone replacement therapy

BACKGROUND

Growth hormone deficiency is associated with increased morbidity and mortality from cardiovascular diseases, which might be related to changes in glucose and lipid metabolism.

DESIGN

To assess the influence of long-term growth hormone replacement therapy (GHRT) on glucose metabolism we examined eight growth hormone-deficient (GHD) adults (seven female/one male; age, 46 +/- 3 years; body mass index, 31 +/- 2 kg m-2) over a period of 18 months in comparison to an adequate control group consisting of eight obese subjects matched for age, sex, and body mass index. We performed frequently sampled intravenous glucose tolerance tests (FSIGT) with minimal model analysis before the study, and after 12 and 18 months.

RESULTS

Following GHRT, insulin-like growth factor-1 (IGF-1) increased significantly from a basal level of 75.9 +/- 18.9 to 200.8 +/- 31.0 microg L-1 after 12 months of therapy and remained stable, thereafter. GHRT did not affect fasting blood glucose, basal insulin, cholesterol, blood pressure and body weight. However, at 12 months, HbA1c (6.0 +/- 0.1 vs. 5.6 +/- 0.1% at basal, P < 0.05) and triglyceride (2.3 +/- 0.4 vs. 1.4 +/- 0.3 mmol L-1) significantly increased but returned to pretreatment values at 18 months. Insulin sensitivity was higher in GHD (8.2 +/- 3.1) compared to controls (3. 6 +/- 0.53 x 10-4 min-1/(microU mL-1), P = 0.06) and decreased significantly after 18 months of GHRT to 5.1 +/- 2.6, P < 0.05. Basal insulin secretion was similar to that in the control group and increased significantly after 12 and 18 months, total insulin secretion only after 12 months. SG (glucose effectiveness)was lower in GHD patients (0.0095 +/- 0.001 min-1) compared to controls (0.020 +/- 0.003 min-1, P < 0.05) and increased significantly after 12 and 18 months of GHRT (0.016 +/- 0.002, and 0.015 +/- 0.001 min-1, P < 0. 05), respectively. Hepatic insulin extraction rate was similar in both groups and remained unchanged following GHRT.

CONCLUSION

We conclude that long-term GHRT induces a significant decrease of the increased insulin sensitivity in GHD patients to levels observed in body mass index-matched control subjects. This is accompanied by an increase in basal and total insulin secretion as well as in glucose effectiveness as a possible compensatory mechanism.

Prevalence of C-cell hyperplasia in patients with normal basal and pentagastrin-stimulated calcitonin

The prevalence of thyroid C-cell hyperplasia (CCH) was investigated prospectively in 57 patients with normal preoperative pentagastrin-stimulated plasma concentrations of calcitonin (hCT, range, 1-60 pg/mL; normal, 100 pg/mL) who subsequently underwent total thyroidectomy due to thyrotoxicosis (n = 18) or to nodular thyroid disease in the presence (n = 9) or absence (n = 30) of cytological follicular neoplasia. CCH was seen in 28 of 57 (49%) of all patients. CCH was more common in hyperthyroid (12/18 [66%]) than in euthyroid (16/39 [41%] patients. No age- or gender-related differences in the occurrence of CCH was seen. There was no histological evidence of medullary thyroid carcinoma (MTC) in any patient. CCH classified histologically as neoplastic was encountered in two instances. It was concluded that CCH may be expected in almost 50% of normocalcitonemic patients with various thyroid disorders. Although the potential clinical importance of this histological finding and specifically its neoplastic variety remains unknown, these results are in keeping with the assumption that pentagastrin-stimulated plasma concentrations of hCT within the normal range do not exclude the presence of CCH.

Basal calcitonin levels and the response to pentagastrin stimulation in patients after kidney transplantation or on chronic hemodialysis as indicators of medullary carcinoma

Plasma concentrations of calcitonin (hCT) were determined in 150 patients with chronic renal failure on chronic hemodialysis therapy (CHD) and in 800 patients after successful kidney transplantation (KT). Basal hCT concentrations exceeded 10 pg/mL in 44 of 150 patients (29%) with CHD and in 48 of 800 (6%) in patients with KT. Among these patients with elevated basal hCT, pentagastrin-stimulated concentrations of hCT exceeded 100 pg/mL in 4 patients with CHD and in 7 with KT. Thyroidectomy was performed in 8 patients (5 with KT, 3 with CHD) revealing the presence of medullary thyroid carcinoma (MTC) (n = 2) or of C-cell hyperplasia (n = 6). Two patients with C-cell hyperplasia had the neoplastic form of this disorder. One patient with MTC and 1 with C-cell hyperplasia also presented a papillary microcarcinoma. Stimulated concentrations of hCT were only moderately elevated in the remaining 3 patients and follow-up rather than surgery was deemed appropriate due to their concomitant severe medical problems. In conclusion, basal concentrations of hCT higher than 10 pg/mL are more common in patients with CHD (29%) and after successful KT (6%) than previously described in patients with thyroid nodular disease (3%). In spite of various additional factors complicating the interpretation of elevated hCT in CHD, pentagastrin-stimulated values above 100 pg/mL must be considered to indicate the presence of C-cell hyperplasia and/or of medullary thyroid carcinoma. Although thyroidectomy would theoretically be the therapy of choice, the potential benefit of the operation must be seen in the context of the patient's general condition.

Adrenal function in patients with chronic renal failure

Previous studies have reported divergent findings on the function of the hypothalamic-pituitary-adrenal axis in patients with chronic renal failure (CRF). The low-dose adrenocorticotropin (ACTH) test offers the possibility of unmasking adrenal dysfunction, which might remain undiscovered using the ACTH test with the standard 250-microg dose. Furthermore, the choice of renal replacement therapy (either hemodialysis or continuous ambulatory peritoneal dialysis [CAPD]) might have an impact on adrenal function. To investigate these possibilities, ACTH tests were performed with three different doses (ie, 1, 5, and 250 microg) in 14 CRF patients and in seven healthy controls. Seven of the CRF patients were receiving chronic hemodialysis and seven were receiving CAPD. Basal plasma concentrations of cortisol were comparable in the three groups tested (5.3+/-0.4 microg/dL in the controls, 6.6+/-0.7 microg/dL in the hemodialysis patients, and 7.9+/-1.0 microg/dL in the CAPD patients), whereas basal ACTH concentrations were significantly elevated in the CRF patients (28.5+/-3.8 pg/mL in the hemodialysis patients and 33.0+/-6.0 pg/mL in the CAPD patients) when compared with normal controls (17.0+/-1.4 pg/mL; P < 0.05). All three doses of ACTH resulted in a rapid increase of plasma cortisol concentrations that was comparable in all three groups. In the hemodialysis patients, a trend toward a diminished response to the lowest dose of 1 microg was noticed. We conclude, therefore, that adrenal response to ACTH in various doses is unaffected in CRF independent of whether hemodialysis or CAPD is chosen for renal replacement therapy.

Effects of parathyroid hormone and serum calcium on the phenotype and function of mononuclear cells in patients with primary hyperparathyroidism

BACKGROUND

Several studies have demonstrated specific influence of parathyroid hormone (PTH) on immune parameters, especially on T- and B-cell function, migration of polymorphonuclear leucocytes (PMNLs) and antibody synthesis, in patients with secondary hyperparathyroidism and chronic renal failure and recently also in patients with primary hyperparathyroidism (pHPT).

METHODS

We therefore examined 12 patients with pHPT before and 6 months after parathyroidectomy (PTX) and nine sex- and age-matched control subjects to determine the impact of PTH and serum calcium concentrations on several immune parameters, including (a) serum concentrations of immunoglobulins, (b) immunophenotype of peripheral blood lymphocytes, (c) phytohaemagglutinin (PHA)-induced lymphocyte proliferation and (d) monocytic surface marker expression.

RESULTS

Serum concentrations of immunoglobulins (IgG, IgA, IgM) were unaffected by elevated serum PTH and calcium levels. T lymphocytes (CD3), B lymphocytes (CD19), NK cells (CD16/56) and monocytes (CD16) revealed a normal distribution and were not different before and after PTX in patients with pHPT when compared with the control group. CD4+ T-helper lymphocytes were significantly elevated pre- and post-operatively in patients with pHPT. The lymphocyte proliferation response to PHA in the highest concentration (12.5 micrograms L-1) tested was significantly suppressed in patients with pHPT preoperatively when compared with the patients post-operatively and the control group. In addition, both CD4+ and CD8+ lymphocytes showed a lower expression of activation markers, interleukin 2 (IL-2) receptor (CD25) and transferrin receptor (CD71), which could be partially restored 6 months after PTX, but did not reach normal values.

CONCLUSION

In summary, in contrast to the findings in patients with secondary HPT, pHPT appears to be associated with less alterations of immune functions. Chronically elevated serum PTH and calcium concentrations in patients with pHPT induce a higher percentage of CD4+ helper T lymphocytes and a suppressed lymphocyte response to PHA as well as a reduced expression of activation markers on peripheral blood lymphocytes.

Effect of long-term growth-hormone substitution therapy on bone mineral density and parameters of bone metabolism in adult patients with growth hormone deficiency

Reduced bone mineral density (BMD) and the prevalence for osteoporotic vertebral fractures are symptoms of growth hormone deficiency (GHD) syndrome, and GH replacement therapy is now available for GH-deficient adults. We investigated the long-term effects of GH replacement therapy on bone mineral density (BMD) and bone metabolism in 19 adult patients with GHD over a period of 18 months. In response to GH treatment, the initially decreased IGF-I concentrations rose significantly during 18 months of therapy to levels within the normal range (matched for sex and age) (mean change 158.1 +/- 50.8 ng/ml, P < 0.001). Parameters of bone formation such as osteocalcin (OC) and procollagen I-C-Peptide (PICP) showed a significant increase in the first 6 months of therapy, followed by a slight decrease in the next months. Markers of bone resorption (CrosslapsR and deoxypyridinoline (D-Pyr) also increased significantly with a peak value after 6 months and all parameters except PICP remained above baseline values after 18 months. BMD of the femoral neck (FN) showed an increase after 18 months of therapy (mean change 0.01 +/- 0.03 g/cm2 after 18 months, n.s.). However, the increase in BMD was significant only in the lumbar spine (LS) (mean change 0.03 +/- 0.04 g/cm2, P < 0.05 after 18 months). We conclude that GH replacement therapy in adult patients with GHD over a period of 18 months causes a pronounced increase in bone turnover mainly during the first 12 months of therapy and increases BMD of the lumbar spine and the femoral neck after 18 months.

Effect of elevated serum prolactin concentrations on the immunophenotype of human lymphocytes, mitogen-induced proliferation and phagocytic activity of polymorphonuclear cells

It has been suggested that the immune system is an important target tissue of prolactin (PRL). We therefore investigated several immune parameters in nine patients with chronically elevated serum prolactin concentrations. The immunophenotype of lymphocytes, mitogen-induced lymphocyte proliferation and phagocytic activity of polymorphonuclear cells were determined under high serum prolactin levels and 2 weeks after treatment with dopamine agonists. An increased CD4/CD8 ratio in the hyperprolactinaemic patients could be detected compared with healthy control subjects, which remained high after treatment and did not seem to correlate with serum prolactin concentrations. Peripheral blood B lymphocytes showed an increased expression of CD69 in the treated group but not in untreated patients compared with healthy control subjects. Interleukin 2 receptor, CD45RO, transferrin receptor or HLA-DR expression of CD4 or CD8 cells, as well as oxidative burst and phagocytic activity of granulocytes, were not affected in the patients with prolactinomas. Lymphocyte transformation response to phytohaemagglutinin in vitro was found not to be influenced by elevated prolactin levels except at the highest mitogen concentration tested. These data together with previous reports suggest that, although PRL is required for lymphocyte maturation to achieve normal immune function, elevated PRL levels do not lead to an 'overstimulation' of the immune system in men.

Effect of successful parathyroidectomy on hematopoietic progenitor cells and parameters of red blood cells in patients with primary hyperparathyroidism

Elevated levels of parathyroid hormone (PTH) in primary and secondary hyperparathyroidism inhibit hematopoiesis at the level of hematopoietic progenitor cells, mainly the burst forming units-erythroid (BFUe). Removal of parathyroid adenomas is associated with an increase in hematopoietic progenitor cells. In contrast, a certain amount of PTH and calcium is needed to correct anemia after bleeding demonstrating that PTH has also a stimulatory effect on the bone marrow. We examined the effect of parathyroidectomy (PTX) in 10 patients with histologically proven primary hyperparathyroidism on hematopoietic progenitor cells and several parameters of red blood cells before and at 5, 30 and 90 days after PTX. After successful surgery serum levels of iPTH (p < 0.01) and calcium (p < 0.001) decreased significantly. Subsequently a steady increase in all hematopoietic progenitor cell classes was observed reaching significance for BFUe only (p < 0.05). Red blood cells and hemoglobin reached nearly pretreatment values within 90 days after PTX after they had decreased due to surgery associated blood loss. 8 patients undergoing hemithyroidectomy without PTX showed a similar decrease in red blood cells and hemoglobin followed by a rise after the operation. The changes of these parameters did not differ significantly from the patients with pHPT. In contrast to the patients with pHPT, no changes in hematopoietic progenitor cells during the 90 days were observed. The presented data provide further evidence that increased PTH concentrations might inhibit hematopoiesis in humans in vivo. The inhibition can be reversed following PTX by normalisation of PTH concentrations.

The long-acting dopamine agonist bromocriptine mesylate as additive immunosuppressive drug after kidney transplantation

BACKGROUND

Acute rejection is an important risk factor for kidney graft loss. As evidence suggests that prolactin has important immunostimulatory properties, we conducted a randomized, prospective open trial in which bromocriptine, a drug suppressing prolactin secretion, was administered as an additive immunosuppressive drug after first cadaver kidney transplantation.

METHODS

In the treatment group bromocriptine was given intramuscularly to 22 patients after their first kidney transplantation along with conventional immunosuppression (cyclosporin A, glucocorticoids). Twenty-three patients receiving only conventional immunosuppression served as control subjects. The incidence of acute graft rejections, graft losses, and infections was evaluated.

RESULTS

Serum prolactin concentrations were slightly elevated above normal values before transplantation (32 +/- 5.3 ng/ml) and decreased to values between 13 and 16 ng/ml in the control group and were totally suppressed in the bromocriptine group. After 6 months of follow-up overall patient and allograft survival was 97.7% and 91% respectively. Acute rejection episodes occurred in 31 patients (77.5%): 15 in the bromocriptine group vs 20 in the control group (n.s.). In each group eight patients experienced a cytomegalovirus infection. The incidence of severe bacterial infections (i.e. pneumonia and sepsis) was five and six respectively. The necessity of haemodialysis after transplantation was 3.1% in the patients on bromocriptine and 23% in those without.

CONCLUSIONS

Suppression of circulating prolactin concentration by bromocriptine did not improve the clinical outcome of patients after kidney transplantation receiving cyclosporin and prednisolone.

The influence of growth hormone substitution therapy on erythroid and myeloid progenitor cells and on peripheral blood cells in adult patients with growth hormone deficiency

It has been reported that hypophysectomized rats exhibit normochromic, normocytic anaemia. Pancytopenia with impaired DNA synthesis in the bone marrow can be restored in these hypophysectomized rats by syngeneic pituitary grafts placed under the kidney capsule or treatment with growth hormone (GH). Until now, adults with hypopituitarism have received adequate replacement therapy with thyroxine, cortisol and sex steroids, but not with GH. We therefore investigated the effects of GH replacement therapy on the proliferation and differentiation of erythroid and myeloid progenitor and peripheral blood cells in 11 adult patients with growth hormone deficiency in a double-blind, placebo-controlled study for the first 6 months of therapy. The placebo group showed no changes during the first 6 months without therapy in either insulin-like growth factor I (IGF-I) levels, erythroid and myeloid progenitor precursor cells or peripheral blood cells. After commencement of GH therapy, IGF-I levels rose significantly during 24 months of therapy from 75.3 +/- 13.5 to 225 +/- 34.7 ng mL-1 (P < 0.001). Erythroid and myeloid progenitor precursor cells showed a steep and significant increase after 18 and 24 months of therapy (erythroid: from 10.7 +/- 3.5 to 261.4 +/- 79.8, P < 0.02, after 18 months and to 276.8 +/- 149.8 x 10(5) mononuclear cell colonies, P < 0.03, after 24 months; granulocyte-macrophage colony-forming units: from 39.7 +/- 9.8 to 316.9 +/- 124.6, P < 0.002, after 18 months and to 366 +/- 188.7 x 10(5) mononuclear cell colonies, P < 0.03, after 24 months), whereas the peripheral red and white blood cells exhibited only minimal non-significant changes. The principal regulators of erythropoiesis, such as erythropoietin, and parameters reflecting erythropoiesis in the peripheral blood, such as reticulocytes, remained almost unchanged throughout the whole study period. We therefore conclude that patients with GH deficiency do not have anaemia, but have haematopoietic precursor cells in the lower normal range, and that GH substitution therapy over a period of 24 months has a marked effect on erythroid and myeloid progenitor precursor cells but only negligible effects on peripheral blood cells in GH-deficient adults.

Impact of high-dose oral acyclovir prophylaxis on cytomegalovirus (CMV) disease in CMV high-risk renal transplant recipients

Recent studies showed contradictory results concerning the efficacy of oral acyclovir in the prevention or amelioration of cytomegalovirus (CMV) disease after renal transplantation (TX). This study evaluated the incidence and severity of CMV disease within the first year after TX in high-risk renal transplant recipients (CMV-seropositive donor, seronegative recipient) treated prophylactically with oral acyclovir (800 to 3200 mg/day) over a period of 12 wk (ACY, N = 22), compared with high-risk patients randomly assigned as controls (CO, N = 10). Follow-up for CMV infection included serological determination of CMV-specific immunoglobulin G and immunoglobulin M antibodies, antigen detection in peripheral blood leukocytes (PP 65), shell vial culture (blood), and virus isolation/early antigen detection (urine). Severity of CMV disease was quantified by a scoring system for CMV-related symptoms. Nine patients (40.1%) in the acyclovir group and four patients (40%) in the control group developed CMV disease. Neither severity (ACY, 11.4 versus CO; 12.5 points score), nor duration of disease (ACY, 21 days; CO, 22 days), nor transplant function at the end of the observation period differed significantly. The onst of CMV disease was not delayed significantly in acyclovir-treated patients compared with controls (ACY, 47 +/- 34 days versus CO, 27 +/- 14 days after TX, not significant). Our results show no beneficial effect of oral acyclovir prophylaxis in CMV high-risk renal transplant recipients.

Factitious hyperthyroidism causing acute myocardial infarction

Myocardial ischemia is a rare but severe and possibly life threatening manifestation of hyperthyroidism, but does not usually result in persistent ischemia. We report on a 71-year-old woman who had undergone total thyroidectomy with subsequent irradiation because of follicular carcinoma 3 years ago. Since then, she had been maintained on oral levothyroxine replacement therapy at a dose of 0.15 mg alternating with 0.2 mg daily. When latent hypothyroidism became evident despite replacement therapy, the dose of levothyroxine was increased to 0.3 mg a day. Three weeks later, the patient suffered from an acute posterior myocardial infarction, although she had no previous history of coronary artery disease. Subsequent coronary arteriograms revealed no evidence of disease of the major vessels. Myocardial scintigraphy 3 weeks after infarction still revealed a persistent perfusion defect. Since it is known that thyroid hormones increase oxygen demand, the rapid elevation of oxygen utilization caused by thyrotoxicosis factitia is likely to be responsible for this patient's myocardial infarction. The case illustrates that a sudden increase in levothyroxine replacement dose should be avoided.

Effect of danazol-induced chronic hyperglucagonaemia on glucose tolerance and turnover

It has been shown that danazol (14-ethinyltestosterone) induces hyperglucagonaemia. To investigate the effect of chronic glucagon excess on carbohydrate metabolism, we studied six patients before and after treatment with danazol for immunothrombopenia. Glucose tolerance and insulin, C-peptide and glucagon secretion during an oral glucose tolerance test (oGTT) as well as peripheral and hepatic insulin sensitivity were determined by means of euglycaemic clamp technique (40 mU m-2 min-1) before and after 3 months of danazol therapy. Overall glucose turnover (Rd) was assessed radioisotopically. (1) Plasma glucagon levels rose significantly from 88 +/- 16 pg mL-1 before to 683 +/- 148 pg mL-1 after therapy (P < 0.01). (2) Glucose levels during an oGTT were not significantly different before and after therapy. Glucose-stimulated insulin secretion at 60 and 120 min and the area under the curve (AUC) for insulin during the oGTT, were significantly increased after danazol treatment compared with pre-treatment values (P < 0.05), whereas glucagon secretion showed a similar decrease at both time points of investigation (NS). (3) Rd during steady state showed a significant decrease during the entire period of euglycaemic clamp following therapy (after 240 min, 3.8 +/- 0.6 vs. 5.3 +/- 0.7 mg kg-1 min-1, P < 0.05). The decline in glucagon during the clamp was similar during steady state before and after therapy. (4) Basal hepatic glucose output did not differ significantly before and after therapy (1.74 +/- 0.41 vs. 1.45 +/- 0.22 mg kg-1, NS), whereas hepatic glucose output during the clamp was significantly less suppressed after danazol therapy. The authors conclude that chronic glucagon excess leads to a decrease in peripheral and hepatic insulin action which is accompanied by an increase in insulin secretion.

Effect of elevated growth hormone concentrations on the phenotype and functions of human lymphocytes and natural killer cells

Over the past decades, strong evidence has accumulated that growth hormone (GH) has immunostimulatory properties. Therefore, an investigation was conducted on 10 acromegalic patients and 9 age- and sex-matched healthy controls to determine whether plasma GH concentrations correlate with changes in several immune parameters, including serum concentrations of immunoglobulins, lymphocyte subsets, lymphocyte transformation with phytohemagglutinin (PHA), natural killer (NK) cell activity as well as phagocytic and metabolic burst activity. While NK cell activity, serum concentrations of immunoglobulins (IgG, IgM, IgA) and metabolic burst activity were within the normal range in both groups, a significantly enhanced phagocytic activity was observed in the acromegalic patients. Surface markers on T lymphocytes (CD3, CD4, CD8), B lymphocytes (CD19) and NK cells (CD16/56) were normal in both groups; however, in the acromegalic subjects, CD4+ and CD8+ cells showed a significant higher expression of transferrin receptors (CD71), indicating enhanced T-cell activity. The lymphocyte transformation response to PHA at the highest concentration tested showed a tendency to be elevated in acromegalics; however, the difference failed to be significant. Long-lasting and pronounced elevation of GH in acromegaly induces significantly enhanced phagocytic activity, but only negligible changes in most patients in lymphocyte phenotype and in the lymphocyte response to PHA.

The non ergot D2-dopamine agonist CV 205-502 decreases growth hormone concentrations in acromegalic patients

It was the aim of this study to test for a possible effect of the new non ergot dopamine agonist CV 205-502 on plasma growth hormone (GH) concentrations in acromegaly. 10 acromegalic patients received a single oral dose of 150 micrograms CV 205-502 after an overnight fast. As a control group 7 acromegalic patients undertook the same procedure without receiving any drug. Blood samples were drawn hourly up to 7 hours thereafter for determination of GH. Plasma growth hormone concentrations decreased by 48.8 +/- 8.7%. The nadir was observed 3 hours after CV 205-502 was administered and GH concentrations remained suppressed throughout the 7 hours of the test period. In contrast GH plasma concentrations in the control group remained stable. We conclude that acute administration of CV 205-502 suppresses GH secretion in acromegalic patients and thus could serve as an alternative therapy in acromegaly.

Decrease of serum calcium concentration and lost influence of calcium on parathyroid hormone release in a patient with primary hyperparathyroidism after treatment with diphosphonates

Prolonged decrease of elevated serum calcium levels after treatment with diphosphonates in patients with primary hyperparathyroidism (pHPT) is very rare. A patient with water clear cell hyperplasia and five enlarged glands is presented who received diphosphonates (day 1 through day 8 dichloromethylene diphosphonate orally and a single dose of 60 mg pamidronate on day 8 intravenously) leading to a significant fall in serum calcium levels. Surprisingly, there was no reactive increase in intact parathyroid hormone (PTH) in the following 18 days. Patients with missing PTH regulation to hypocalcemia after diphosphonates who need a period of stabilization prior to parathyroid surgery might benefit most from this therapy.

[Bone density of the lumbar spine and femur in acromegaly]

Acromegaly is regarded as a cause for secondary osteoporosis, whereas recent papers suggest that growth hormone increases bone mineral density (BMD). In 16 patients with active acromegaly we found an increased BMD compared to normal controls in the lumbar spine and the proximal femur by means of dual energy X-ray absorptiometry. This increase in BMD was statistically significant in the femoral neck and in Ward's triangle (P = 0.05). Moreover, no signs of osteoporosis were found radiologically.

Bone mineral density and parameters of bone metabolism in patients with acromegaly

To assess the effect of chronically elevated plasma growth hormone (GH) levels on bone metabolism and bone mineral density (BMD), 16 patients (10 females and 6 males) with a mean age of 49.1 +/- 13.2 years (range 33-68) with active acromegaly were studied and compared to a control group of 16 sex- and age-matched subjects. BMD of the lumbar spine and two different sites of the proximal femur were measured by dual-energy x-ray absorptiometry (Norland XR-26). In the acromegalic patients the mean plasma GH concentration was 30.1 +/- 11.1 micrograms/liter, and the mean plasma somatomedin C (SMC) concentration was 6.5 +/- 1.5 U/liter. Mean serum osteocalcin (OC) levels (14.3 +/- 1.1 versus 7.2 +/- 0.4 ng/ml, p < 0.001) as well as the urinary hydroxyproline excretion (OHP; 8.8 +/- 1.4 versus 2.7 +/- 0.3 mg, p < 0.0001) were significantly higher in the acromegalic patients than in the control subjects. In the acromegalic patients BMD was significantly elevated in the two examined regions of the proximal femur, that is, the femoral neck (1.06 +/- 0.05 versus 0.86 +/- 0.03 g/cm2, p < 0.05) and Ward's triangle (0.92 +/- 0.06 versus 0.76 +/- 0.03 g/cm2, p < 0.02), whereas the BMD of the lumbar spine was not significantly different from that of control subjects. Among the patients with acromegaly a significant positive correlation between serum OC concentrations, on the one hand, and urinary OHP excretion (r = 0.7, p < 0.004) as well as BMD in the proximal femur (r = 0.64, p < 0.007), on the other hand, could be observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of elevated serum prolactin concentrations on cytokine production and natural killer cell activity

In vitro and in vivo studies in rodents and human suggested an immunostimulatory effect of prolactin. The aim of the present study was to determine the impact of chronically elevated serum prolactin concentrations on the immune system in patients with prolactinomas. For this purpose parameters of the humoral and cellular immune system were studied in seven patients with prolactinomas on two occasions (1) when their serum prolactin concentration had been normalized through treatment with dopamine agonists and (2) when their serum prolactin concentration was high. Serum concentrations of immunoglobulines, interleukin 1, 3 and 6, TNF-alpha, interferon-gamma and the soluble interleukin 2 receptor, leukocyte subsets and the natural killer cell activity were found to be within the normal range on both occasions, i.e. at normal and at high serum prolactin concentrations. The assumption could be made that long-lasting elevation of serum prolactin concentration induces adaptive changes when the acute stimulatory effects of prolactin on several parameters of the immune system have subsided.

Treatment and prophylaxis of chemotherapy-induced gastrointestinal complaints

Ninety-eight patients (48 male, 50 female; age median, 56 years; range, 25-85 years) with solid tumors (21 breast cancers, 6 sarcomas, 2 colorectal cancers, 1 pancreatic carcinoma, 1 hypernephroma, and 1 lung cancer) and hematologic neoplasms (24 multiple myelomas, 32 lymphomas, and 10 myeloproliferative syndromes) were recruited into the study. The patients received at least three cycles of chemotherapy with alkylating substances, anthracyclines, antimetabolites, and vinca alkaloids, with or without corticosteroids. A total of 325 cycles of chemotherapy were administered. The symptoms were evaluated by means of a score system on the basis of which heartburn, sensation of repletion, nausea, and cramps were assessed by incidence and degree of severity. Before initiation of concomitant therapy with sucralfate, 47 patients (48%) had symptoms during chemotherapy (heartburn, sensation of repletion, nausea, cramps). After initiation of therapy with sucralfate these symptoms improved in 42 patients (89%); in 6 patients there was a transitory increase in heartburn and nausea. All other patients remained without symptoms in spite of chemotherapy. The evaluation of the patient population as a whole showed a significant decrease of chemotherapy-induced heartburn (p less than 0.01) and nausea (p less than 0.01) during sucralfate therapy. This was tolerated extremely well; side effects were not observed. To summarize, this prospective clinical study shows that sucralfate is an effective and suitable therapeutic principle in long-term therapy for the treatment and prophylaxis of chemotherapy-induced gastrointestinal complaints.

Erythropoietin treatment of anemia associated with multiple myeloma

Anemia is a common complication of multiple myeloma. It resolves early in the disease if chemotherapy induces a complete remission, but persists if the disease progresses, causing disabling symptoms and often requiring blood transfusions. We treated 13 patients with myeloma-associated anemia by administering recombinant human erythropoietin three times a week for six months. Eleven patients (85 percent) had steady increases in hemoglobin levels and eventual correction of the anemia. Their symptoms of anemia subsided, and they reported a heightened sense of well-being. No patient had any adverse side effects, particularly episodes of hypertension. Monitoring of the serum M component showed a predominantly stable tumor load without apparent interaction between the underlying disease and the response to erythropoietin therapy. The number of erythroid burst-forming units in the bone marrow and peripheral blood and the level of erythropoiesis in bone marrow smears increased significantly during therapy. Pretreatment serum levels of erythropoietin were higher in the patients who did not respond and in those who required more than two months of treatment before they responded. Serum iron, ferritin, and transferrin concentrations reflected responses to treatment. We conclude that recombinant human erythropoietin is a promising therapeutic tool for treating myeloma-associated anemia.

[Erythropoietin treatment of tumor-associated anemia in patients with multiple myeloma]

Anemia of malignancy is a complication of neoplastic disease which causes impairing symptoms and often requires blood transfusions. In this clinical trial, we have treated 13 patients suffering from chronic anemia of malignancy and multiple myeloma with recombinant human erythropoietin (rHuEPO) three times a week. Eleven patients responded to the treatment by appropriate increases of their hemoglobin levels and the eventual correction of the anemic state, one non-responding patient had to terminate the treatment early because of transfusion requirements. Under rHuEPO therapy, the evaluated parameters of iron metabolism indicated the enhanced synthesis of hemoglobin. The symptoms of anemia subsided in the responding patients and most of them reported a hightened subjective sense of well-being. No adverse side effects, particularly no episodes of hypertension, were observed in any patient.