ABSTRACT The effects of clonidine, metoclopramide, and insulin on growth hormone, cortisol, and g... more ABSTRACT The effects of clonidine, metoclopramide, and insulin on growth hormone, cortisol, and glucose concentrations in the blood of 17 healthy prepubertal short children (Group A) and five prepubertal growth hormone-deficient children (Group B) were evaluated. The peak serum growth hormone values after insulin and clonidine were significantly higher than after metoclopramide administration. Growth hormone values did not rise above baseline values in Group B patients with any of these three stimuli. Plasma cortisol concentrations did not change with metoclopramide but increased significantly with insulin and decreased significantly after clonidine; no changes in glucose values were noted with either clonidine or metoclopramide. Clonidine appears to be a reliable, sensitive, and safe out-patient stimulation test of growth hormone reserve in prepubertal children, whereas metoclopramide seems not to be a suitable growth hormone-releasing agent in this age group.
Fifty-eight children with cryptorchidism have been given hCG stimulation testing, 31 with bilater... more Fifty-eight children with cryptorchidism have been given hCG stimulation testing, 31 with bilateral cryptorchidism, 22 with unilateral, and 5 with prior unsuccessful orchiopexy. Hormonal studies were carried out prior to and following stimulation. In bilateral cryptorchidism, bilateral descent was observed in 32 percent of cases and in unilateral, the success rate was 55 percent. From their data, the authors concluded that hCG is not indicated if patients present elevated LH and FSH levels or if the basal T levels are in the pubertal range. In the other subjects, the hCG test will permit the determination of the presence or absence of testosterone production and in some cases it results in testicular descent. Finally, in cases of failure that require surgery, the hCG will stimulate tissue growth enhancing the success of orchiopexy.
Growth hormone (GH) has been available for more than 4 decades for the treatment of GH deficiency... more Growth hormone (GH) has been available for more than 4 decades for the treatment of GH deficiency. Initially, GH was extracted from the pituitary glands of human cadavers, but its use was discontinued following the transmission of the Creutzfeldt-Jakob virus. After the development of recombinant GH (somatropin) in 1985, an 'unlimited' commercial source of GH has been available, allowing for the treatment of a large number of short GH-deficient and -sufficient children. Refinements in both the dosage and the frequency of administration of GH have allowed GH-deficient children to reach nearly normal final heights, although mostly they are still below their target heights. Decreased bone mineral densities and increased concentrations of fasting and postprandial lipids, coagulation factors, and several independent cardiovascular risk factors have been reported in GH-deficient children and adolescents and appear to improve with GH administration. The short-term administration of GH to mostly non-GH-deficient short children with Turner syndrome, chronic renal insufficiency (CRI), intrauterine growth retardation (IUGR), and idiopathic short stature (ISS) has resulted in increased growth velocities. In addition, the final height of patients with Turner syndrome and CRI appears to improve with the long-term administration of GH. Final height data are still lacking in adolescents with IUGR, but height standard deviation score and final height predictions appear to improve with therapy. Based on the incomplete and inconclusive available data, one must conclude that GH treatment of children with ISS cannot be advised. The use of GH at replacement doses in children with GH deficiency has resulted in rare and generally reversible adverse effects. The long-term administration of pharmacologic GH doses to short, mostly non-GH-deficient children must, however, still be viewed with caution, as long-term complications cannot as yet be fully evaluated. GH therapy must be individualized and should be limited only to children with severe short stature or a significantly decreased growth velocity, to children under considerable stress due to their short stature, and to patients in whom low GH or low insulin-like growth factor-1 secretion might be the rate-limiting factors for growth. The cost of the medication and the inconvenience of daily GH injections to otherwise mostly healthy short children must also be taken into account.
Constitutional delay of growth and pubertal development is a frequent cause of short stature. The... more Constitutional delay of growth and pubertal development is a frequent cause of short stature. These children have a significant retardation of skeletal age and delayed sexual development. They generally maintain a normal growth curve and tend to attain normal adult height. Although children with constitutional delay of growth are believed to have no medical or endocrine abnormality to explain their short stature, some controversy regarding their growth hormone secretory status has recently surfaced; some authors have reported low growth hormone levels to provocative stimuli and decreased growth hormone secretion during sleep, as well as low somatomedin C values in some children with constitutional delay of growth. Others, however, have found the growth hormone secretory status to be normal and similar to that of a control population. The implications of these findings, particularly in regard to possible forms of therapy, are discussed in some detail.
A group of 168 short but otherwise normal children (group A) and 25 children deficient in growth ... more A group of 168 short but otherwise normal children (group A) and 25 children deficient in growth hormone (GH) (group B) wwere studied with an exercise stimulation test to determine the expected error of this method. In group A, 125 (74.4%) had maximum GH responses greater than 15 ng/ml, 23 (13.7%) had responses between 10 and 15 ng/ml, and 20 (11.9%) had responses less than 10 ng/ml. The mean +/- SD values were 8.4 +/- 0.4 ng/ml at 0 time, 26.3 +/- 15.0 at 20 minutes, and 10.7 +/- 8.3 at 40 minutes. The mean maximum response was 27.7 +/- 14.3 ng/ml. In group B, 22 (88%) had maximum responses less than 10 ng/ml and 3 (12%) had responses between 10 and 15 ng/ml. Patients with maximum responses less than 10 ng/ml have a high probability of being GH-deficinet, whereas patients with responses between 10 and 15 ng/ml are less likely to be GH-deficient. No patients with responses greater than 15 ng/ml were GH-deficient.
Journal of Pediatric Endocrinology and Metabolism, 2002
To evaluate cardiac mass and function, carotid intima-media thickness, and serum lipid and lipopr... more To evaluate cardiac mass and function, carotid intima-media thickness, and serum lipid and lipoprotein (a) (Lpa) levels in children and adolescents with type 1 diabetes mellitus (DM) of short duration. Diabetes mellitus has been found to be an important risk factor for macrovascular disease in adults. Increased serum lipids and Lpa levels have been reported in adolescents with type 1 DM; atherosclerotic vascular lesions involving a combination of fatty degeneration and vessel stiffening of the arterial wall and myocardial involvement impairing diastolic function may be present in adolescents and young adults with type 1 DM. Twenty children and adolescents (10 males, 10 females) diagnosed with type 1 DM before 3.4 +/- 3.3 years with a mean age of 11.9 +/- 3.6 years were studied; their HbA1c levels were 8.0 +/- 1.9%. Twenty healthy non-diabetic controls, 10 males and 10 females, aged 12.1 +/- 3.4 years, matched for height and weight, participated in the study. Fasting blood samples were obtained for lipid and Lpa analysis. Patients underwent transthoracic M-mode and two-dimensional echocardiographic evaluation for measurement of left atrial and ventricular dimensions and left ventricular (LV) wall thickness and mass. Stroke volume and cardiac output were measured using pulsed Doppler echocardiography; carotid intima-media thickness was measured using high-resolution mode B ultrasound. Interventricular septal thickness (7.1 +/- 1.8 vs 7.0 +/- 1.5 mm), LV posterior wall thickness (7.1 +/- 1.4 vs 7.5 +/- 2.0 mm) and LV mass after correction for body surface area (70.6 +/- 27.4 vs 70.7 +/- 18.0 g/m2) were similar in patients and controls. Similarly, the LV ejection fraction at rest was similar in patients and controls (69.9 +/- 2.3 vs 70.0 +/- 0.6%), as were pulmonary venous flow velocities (0.56 +/- 0.09 vs 0.55 +/- 0.10 m/s for diastolic peak velocity, 0.54 +/- 0.08 vs 0.50 +/- 0.09 m/s for systolic peak velocity and 0.17 +/- 0.07 vs 0.19 +/- 0.05 m/s for atrial reversal filling). Carotid intima-media thickness (0.60 +/- 0.02 and 0.59 +/- 0.02 mm for the right and left carotid artery) was similar to that of controls (0.60 +/- 0.03 and 0.61 +/- 0.02 mm for the right and left carotid artery). Low density lipoprotein cholesterol and Lpa levels were increased in patients compared to controls (113.2 +/- 26.0 mg/dl and 20.1 +/- 11.7 mg/dl in patients vs 90.4 +/- 14.3 mg/dl and 9.8 +/- 2.9 mg/dl in controls; p <0.01), while total cholesterol, HDL cholesterol and serum triglyceride concentrations were similar to those in controls. Although children and adolescents with type 1 DM seem not to show alterations in cardiac mass and function or early atherosclerotic changes in the first few years after diagnosis, their cardiovascular risk is increased as they present with dyslipidemia at an early stage of the disease.
The Journal of Clinical Endocrinology and Metabolism, Mar 1, 1980
ABSTRACT An adolecsent male is described with growth failure, normal GH, and elevated somatomedin... more ABSTRACT An adolecsent male is described with growth failure, normal GH, and elevated somatomedin by bioassay, radioreceptorassay, and RIA. A previously unrecognized defect in somatomedin responsiveness is suspected.
Eighteen healthy, short children with normal growth during most of their childhood were evaluated... more Eighteen healthy, short children with normal growth during most of their childhood were evaluated after a sustained fall in weight and reduced linear growth. Growth was followed after nutritional counseling until final height. This report demonstrates the need for an appropriate-for-age weight gain in growing children as a relatively minor but prolonged caloric restriction, leading to a sustained fall in weight centiles, will affect growth velocities long term and may lead to reduced final heights.
ABSTRACT The effects of clonidine, metoclopramide, and insulin on growth hormone, cortisol, and g... more ABSTRACT The effects of clonidine, metoclopramide, and insulin on growth hormone, cortisol, and glucose concentrations in the blood of 17 healthy prepubertal short children (Group A) and five prepubertal growth hormone-deficient children (Group B) were evaluated. The peak serum growth hormone values after insulin and clonidine were significantly higher than after metoclopramide administration. Growth hormone values did not rise above baseline values in Group B patients with any of these three stimuli. Plasma cortisol concentrations did not change with metoclopramide but increased significantly with insulin and decreased significantly after clonidine; no changes in glucose values were noted with either clonidine or metoclopramide. Clonidine appears to be a reliable, sensitive, and safe out-patient stimulation test of growth hormone reserve in prepubertal children, whereas metoclopramide seems not to be a suitable growth hormone-releasing agent in this age group.
Fifty-eight children with cryptorchidism have been given hCG stimulation testing, 31 with bilater... more Fifty-eight children with cryptorchidism have been given hCG stimulation testing, 31 with bilateral cryptorchidism, 22 with unilateral, and 5 with prior unsuccessful orchiopexy. Hormonal studies were carried out prior to and following stimulation. In bilateral cryptorchidism, bilateral descent was observed in 32 percent of cases and in unilateral, the success rate was 55 percent. From their data, the authors concluded that hCG is not indicated if patients present elevated LH and FSH levels or if the basal T levels are in the pubertal range. In the other subjects, the hCG test will permit the determination of the presence or absence of testosterone production and in some cases it results in testicular descent. Finally, in cases of failure that require surgery, the hCG will stimulate tissue growth enhancing the success of orchiopexy.
Growth hormone (GH) has been available for more than 4 decades for the treatment of GH deficiency... more Growth hormone (GH) has been available for more than 4 decades for the treatment of GH deficiency. Initially, GH was extracted from the pituitary glands of human cadavers, but its use was discontinued following the transmission of the Creutzfeldt-Jakob virus. After the development of recombinant GH (somatropin) in 1985, an 'unlimited' commercial source of GH has been available, allowing for the treatment of a large number of short GH-deficient and -sufficient children. Refinements in both the dosage and the frequency of administration of GH have allowed GH-deficient children to reach nearly normal final heights, although mostly they are still below their target heights. Decreased bone mineral densities and increased concentrations of fasting and postprandial lipids, coagulation factors, and several independent cardiovascular risk factors have been reported in GH-deficient children and adolescents and appear to improve with GH administration. The short-term administration of GH to mostly non-GH-deficient short children with Turner syndrome, chronic renal insufficiency (CRI), intrauterine growth retardation (IUGR), and idiopathic short stature (ISS) has resulted in increased growth velocities. In addition, the final height of patients with Turner syndrome and CRI appears to improve with the long-term administration of GH. Final height data are still lacking in adolescents with IUGR, but height standard deviation score and final height predictions appear to improve with therapy. Based on the incomplete and inconclusive available data, one must conclude that GH treatment of children with ISS cannot be advised. The use of GH at replacement doses in children with GH deficiency has resulted in rare and generally reversible adverse effects. The long-term administration of pharmacologic GH doses to short, mostly non-GH-deficient children must, however, still be viewed with caution, as long-term complications cannot as yet be fully evaluated. GH therapy must be individualized and should be limited only to children with severe short stature or a significantly decreased growth velocity, to children under considerable stress due to their short stature, and to patients in whom low GH or low insulin-like growth factor-1 secretion might be the rate-limiting factors for growth. The cost of the medication and the inconvenience of daily GH injections to otherwise mostly healthy short children must also be taken into account.
Constitutional delay of growth and pubertal development is a frequent cause of short stature. The... more Constitutional delay of growth and pubertal development is a frequent cause of short stature. These children have a significant retardation of skeletal age and delayed sexual development. They generally maintain a normal growth curve and tend to attain normal adult height. Although children with constitutional delay of growth are believed to have no medical or endocrine abnormality to explain their short stature, some controversy regarding their growth hormone secretory status has recently surfaced; some authors have reported low growth hormone levels to provocative stimuli and decreased growth hormone secretion during sleep, as well as low somatomedin C values in some children with constitutional delay of growth. Others, however, have found the growth hormone secretory status to be normal and similar to that of a control population. The implications of these findings, particularly in regard to possible forms of therapy, are discussed in some detail.
A group of 168 short but otherwise normal children (group A) and 25 children deficient in growth ... more A group of 168 short but otherwise normal children (group A) and 25 children deficient in growth hormone (GH) (group B) wwere studied with an exercise stimulation test to determine the expected error of this method. In group A, 125 (74.4%) had maximum GH responses greater than 15 ng/ml, 23 (13.7%) had responses between 10 and 15 ng/ml, and 20 (11.9%) had responses less than 10 ng/ml. The mean +/- SD values were 8.4 +/- 0.4 ng/ml at 0 time, 26.3 +/- 15.0 at 20 minutes, and 10.7 +/- 8.3 at 40 minutes. The mean maximum response was 27.7 +/- 14.3 ng/ml. In group B, 22 (88%) had maximum responses less than 10 ng/ml and 3 (12%) had responses between 10 and 15 ng/ml. Patients with maximum responses less than 10 ng/ml have a high probability of being GH-deficinet, whereas patients with responses between 10 and 15 ng/ml are less likely to be GH-deficient. No patients with responses greater than 15 ng/ml were GH-deficient.
Journal of Pediatric Endocrinology and Metabolism, 2002
To evaluate cardiac mass and function, carotid intima-media thickness, and serum lipid and lipopr... more To evaluate cardiac mass and function, carotid intima-media thickness, and serum lipid and lipoprotein (a) (Lpa) levels in children and adolescents with type 1 diabetes mellitus (DM) of short duration. Diabetes mellitus has been found to be an important risk factor for macrovascular disease in adults. Increased serum lipids and Lpa levels have been reported in adolescents with type 1 DM; atherosclerotic vascular lesions involving a combination of fatty degeneration and vessel stiffening of the arterial wall and myocardial involvement impairing diastolic function may be present in adolescents and young adults with type 1 DM. Twenty children and adolescents (10 males, 10 females) diagnosed with type 1 DM before 3.4 +/- 3.3 years with a mean age of 11.9 +/- 3.6 years were studied; their HbA1c levels were 8.0 +/- 1.9%. Twenty healthy non-diabetic controls, 10 males and 10 females, aged 12.1 +/- 3.4 years, matched for height and weight, participated in the study. Fasting blood samples were obtained for lipid and Lpa analysis. Patients underwent transthoracic M-mode and two-dimensional echocardiographic evaluation for measurement of left atrial and ventricular dimensions and left ventricular (LV) wall thickness and mass. Stroke volume and cardiac output were measured using pulsed Doppler echocardiography; carotid intima-media thickness was measured using high-resolution mode B ultrasound. Interventricular septal thickness (7.1 +/- 1.8 vs 7.0 +/- 1.5 mm), LV posterior wall thickness (7.1 +/- 1.4 vs 7.5 +/- 2.0 mm) and LV mass after correction for body surface area (70.6 +/- 27.4 vs 70.7 +/- 18.0 g/m2) were similar in patients and controls. Similarly, the LV ejection fraction at rest was similar in patients and controls (69.9 +/- 2.3 vs 70.0 +/- 0.6%), as were pulmonary venous flow velocities (0.56 +/- 0.09 vs 0.55 +/- 0.10 m/s for diastolic peak velocity, 0.54 +/- 0.08 vs 0.50 +/- 0.09 m/s for systolic peak velocity and 0.17 +/- 0.07 vs 0.19 +/- 0.05 m/s for atrial reversal filling). Carotid intima-media thickness (0.60 +/- 0.02 and 0.59 +/- 0.02 mm for the right and left carotid artery) was similar to that of controls (0.60 +/- 0.03 and 0.61 +/- 0.02 mm for the right and left carotid artery). Low density lipoprotein cholesterol and Lpa levels were increased in patients compared to controls (113.2 +/- 26.0 mg/dl and 20.1 +/- 11.7 mg/dl in patients vs 90.4 +/- 14.3 mg/dl and 9.8 +/- 2.9 mg/dl in controls; p <0.01), while total cholesterol, HDL cholesterol and serum triglyceride concentrations were similar to those in controls. Although children and adolescents with type 1 DM seem not to show alterations in cardiac mass and function or early atherosclerotic changes in the first few years after diagnosis, their cardiovascular risk is increased as they present with dyslipidemia at an early stage of the disease.
The Journal of Clinical Endocrinology and Metabolism, Mar 1, 1980
ABSTRACT An adolecsent male is described with growth failure, normal GH, and elevated somatomedin... more ABSTRACT An adolecsent male is described with growth failure, normal GH, and elevated somatomedin by bioassay, radioreceptorassay, and RIA. A previously unrecognized defect in somatomedin responsiveness is suspected.
Eighteen healthy, short children with normal growth during most of their childhood were evaluated... more Eighteen healthy, short children with normal growth during most of their childhood were evaluated after a sustained fall in weight and reduced linear growth. Growth was followed after nutritional counseling until final height. This report demonstrates the need for an appropriate-for-age weight gain in growing children as a relatively minor but prolonged caloric restriction, leading to a sustained fall in weight centiles, will affect growth velocities long term and may lead to reduced final heights.
Uploads
Papers by Roberto L Lanes