A randomised study of two doses of biosynthetic human growth hormone on final height of pubertal children with growth hormone deficiency.

AIMS: To determine the effectiveness of different doses of r-hGH therapy during puberty in children with growth hormone deficiency (GHD). METHODS: Randomized controlled trial of different doses of r-hGH therapy administered during puberty in 49 children with GHD. The patients were allocated randomly using a random number table to one of two groups: group 1 (15 IU/m(2)/week) or group 2 (30 IU/m(2)/week). Patients were included if they had received r-hGH daily at a dose of 15 IU/m(2)/week (0.7 mg/m(2)/day) for at least 1 year before randomization. RESULTS: Height increase standard deviation scores (SDS) were similar between the two groups (group 1: 1.1; group 2: 1.2; p = 0.81). CONCLUSION: A higher dose of r-hGH administered during puberty does not appear to have a significant effect on final height of children with GH deficiency. Altering pubertal tempo or intensifying prepubertal r-hGH therapy may be a more promising approach to improving final height in children with GH deficiency.

A randomised study of the effect of two doses of biosynthetic human growth hormone on final height of children with familial short stature.

BACKGROUND/AIMS: The effects of biosynthetic human growth hormone (r-hGH) in children with familial short stature (FSS) are varied. We determined whether responsivity to r-hGH in FSS is dose-dependent. METHOD: Randomised trial of two doses (20 or 40 IU/m(2) body surface area/week by daily subcutaneous injection) of r-hGH in 29 (24 male, 5 female) FSS children with assessment at adult height. RESULTS: Age range at presentation was 5.1-10.5 years, height less than 1.5 standard deviation scores (SDS) below the mean, height velocity SDS greater than -1.5 and peak growth hormone response to provocative testing over 13.5 mU/l. Adult height data (SDS) at 16.5 +/- 2.1 years for the low-dose group and 16.1 +/- 1.1 years for the high-dose group (p = 0.62) were similar [low dose -1.06 (SD 0.75), high dose -1.02 (SD 0.83); p = 0.88]. The incremental effect of both doses on stature was minimal [low-dose difference in height actual-predicted 0.79 (SD 0.94), high dose 1.27 (SD 0.88); p = 0.12]. CONCLUSION: Using this r-hGH dosing schedule there were little short- or long-term effects on height in children with FSS.

Sexual dimorphism in the synchrony of joint growth hormone and cortisol dynamics in children with classic 21-hydroxylase deficiency.

In humans, growth hormone (GH) and cortisol are secreted in a pulsatile fashion and a mutual bidirectional interaction between the GH/insulin-like growth factor (IGF)-I axis and hypothalamic-pituitary-adrenal (HPA) axis has been established. Classic congenital adrenal hyperplasia (CAH) is characterized by a defect in the synthesis of glucocorticoids and often mineralocorticoids, and adrenal hyperandrogenism. In view of the sexually dimorphic pattern in GH secretion, we investigated the GH-cortisol bihormonal secretory dynamics in male and female children with classic CAH. Thirty-eight children with classic 21-hydroxylase deficiency (M: 13, F: 25; age range: 6.1-18.8 yr) were studied prospectively. Serum GH and cortisol concentrations were determined at 20 min intervals for 24 hours. The irregularity of GH and cortisol pattern was assessed using approximate entropy (ApEn), a scale- and model-independent statistic. The synchrony of joint GH-cortisol dynamics was quantified using the cross-ApEn statistic. Cross-correlation analysis of GH and cortisol concentrations was computed at various time lags covering the 24-h period. There was no gender difference in mean 24-hour serum GH (males vs females: 5.25 +/- 4.72 vs 4.44 +/- 2.64 mIU/l) or cortisol (156.2 +/- 44.6 vs 172.0 +/- 58.5 nmol/l) concentrations. For GH, ApEn values were significantly higher in females (0.66 +/- 0.14) than in males (0.53 +/- 0.16) (p = 0.009). No difference in cortisol ApEn values was noted between sexes (0.53 +/- 0.21 vs 0.54 +/- 0.12). Cross-ApEn values of paired GH-cortisol, with cortisol leading GH, were significantly higher in females (0.94 +/- 0.14) than in males (0.83 +/- 0.20) (p = 0.03). These findings suggest that females with classic 21-hydroxylase deficiency have a more irregular pattern of GH secretion and a more asynchronous joint GH and cortisol dynamics than their male counterparts.

Hypothalamo-pituitary-adrenal axis integrity after cranial irradiation for childhood posterior fossa tumours.

BACKGROUND: The evolution of anterior pituitary deficits after treatment for pituitary tumours has been largely attributed to local irradiation, but may be influenced as much by tumour mass or surgery. Other than growth hormone (GH) insufficiency, the late endocrinopathies after survival from non-central brain tumours have been little documented. The aim of this study was to investigate the hypothalamic-pituitary-adrenal (HPA) axis in long-term survivors of cranial irradiation for childhood posterior fossa tumours. PROCEDURE: We studied long-term data in patients treated prepubertally for posterior fossa brain tumours and systematically referred by radiation oncologists for growth and pubertal monitoring to the London Centre for Paediatric Endocrinology over the last 25 years. They must have undergone HPA axis assessment twice, first prepubertally at documentation of growth failure, and second at completion of growth and puberty. Data on sixteen patients (12 males, 4 females; median age: 5.7 years, range: 2.5-8.8 years), who had undergone excision surgery with high dose cranial irradiation and/or chemotherapy for childhood posterior fossa tumours, were examined. Patients were followed for a median of 11.0 (range: 6.8-21.4) years after radiotherapy. HPA axis assessment was undertaken with the insulin-induced hypoglycaemia test (ITT). Basal thyroid, cortisol and gonadal function tests were undertaken annually throughout the follow-up period and any deficits replaced. RESULTS: At each ITT, all patients mounted an inadequate GH response. By the end of the follow-up period all patients remained severely GH deficient, two (12.5%) had partial ACTH insufficiency, one (6.3%) had secondary hypothyroidism but none were gonadotropin deficient or hyperprolactinaemic. CONCLUSIONS: Unlike the severe, evolving multiple pituitary deficits after treatment of pituitary or central tumours in adults, these findings in children with posterior fossa tumours suggest that, with the exception of GH, neurotoxicity due to irradiation per se is associated with a low prevalence of anterior pituitary hormone deficiencies, even at a long follow-up. Since the children in this study were selected for assessment on the basis of growth failure, the high prevalence of GH insufficiency at first testing is to be expected; however, the early onset (within 1-3 years of irradiation) and permanence we have identified supports the view that GH is the most sensitive hormone to radiation injury.

Treatment with flutamide decreases cortisol clearance: implications for therapy in congenital adrenal hyperplasia.

BACKGROUND: Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is characterized by a defect in cortisol and often aldosterone secretion, and adrenal hyperandrogenism. Current treatment is to provide adequate glucocorticoid and mineralocorticoid substitution to prevent adrenal crises and to suppress excess adrenocortical androgen secretion. Anti-androgen therapy with flutamide is an option that allows control of hyperandrogenism without recourse to supraphysiological doses of glucocorticoid. METHODS: We examined the pharmacokinetic parameters of hydrocortisone administered i.v. as a bolus at a dose of 15 mg/m2 in a 17.3 year-old female patient with classic CAH before and four weeks after institution of flutamide treatment by determining serum cortisol concentrations at 10 min intervals for 6 h following the i.v. bolus of hydrocortisone. RESULTS: Treatment with flutamide resulted in a decrease in cortisol clearance from 420 ml/l to 305 ml/l (27% reduction), and a decrease in volume of distribution from 51.61 to 451 (12.9% reduction). The half-life of cortisol increased from 85.3 min to 102.1 min. CONCLUSIONS: Flutamide treatment decreases cortisol clearance, thereby prolonging its half-life. These findings indicate that a reduction in the daily dose of glucocorticoid replacement may need to be considered when flutamide is added to the treatment regimen of patients receiving hydrocortisone.

Why is management of patients with classical congenital adrenal hyperplasia more difficult at puberty?

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is an autosomal recessive condition in which deletions or mutations of the cytochrome P450 21-hydroxylase gene cause glucocorticoid and often mineralocorticoid deficiency. Despite optimal substitution therapy, control of classical CAH is often inadequate at puberty, and the problems encountered relate to hypocortisolism and/or hyperandrogenism. A number of physiological alterations in the endocrine milieu at puberty, which include alterations in the growth hormone/insulin-like growth factor axis, insulin sensitivity, as well as the activity of enzymes participating in cortisol metabolism and adrenal steroidogenesis, may account for the documented hypocortisolism and elevated androgen production, and may explain the difficulty in maintaining adequate adrenocortical suppression in pubertal patients with classical 21-hydroxylase deficiency.

Serum cortisol and 17-hydroxyprogesterone interrelation in classic 21-hydroxylase deficiency: is current replacement therapy satisfactory?

One of the main aims in the management of patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency is to achieve adequate suppression of the adrenal cortex with the smallest possible dose of glucocorticoid substitution. To evaluate the administration schedule of current replacement therapy regimens, we investigated the cortisol-17-hydroxyprogesterone interrelation in 36 patients (13 males and 23 females; median age, 12.3 yr; range, 6.1-18.8 yr) with salt-wasting congenital adrenal hyperplasia. As sufficient variation in 17-hydroxyprogesterone concentrations was required to allow analysis of the cortisol-17-hydroxyprogesterone interrelation, patients were divided into 2 groups depending on the adequacy of hypothalamic-pituitary-adrenal axis suppression. The first group consisted of 17 patients with suppressed 17-hydroxyprogesterone concentrations (group 1), and the second group consisted of 19 patients with nonsuppressed 17-hydroxyprogesterone concentrations (group 2). We determined serum cortisol and 17-hydroxyprogesterone concentrations at 20-min intervals for a total of 24 h while patients were receiving their usual replacement treatment with hydrocortisone and 9alpha-fludrocortisone. We also determined the lowest dose of dexamethasone required to suppress the 0800 h serum ACTH concentrations when administered as a single dose (0.3 or 0.5 mg/m(2)) the night before. Mean 24-h cortisol and 17-hydroxyprogesterone concentrations were 3.9 microg/dl (SD = 2.1) and 66.2 ng/dl (SD = 92.7), respectively, in group 1 and 4.1 microg/dl (SD = 2.5) and 4865.7 ng/dl (SD = 6951) in group 2. The 24-h 17-hydroxyprogesterone concentrations demonstrated circadian variation, with peak values observed between 0400-0900 h. In group 2, 17-hydroxyprogesterone concentrations decreased gradually in response to the rise in cortisol concentrations during the day, but remained low during the night despite the almost undetectable cortisol concentrations between 1600-2000 h. Mean 0800 h androstenedione concentrations correlated strongly with integrated 17-hydroxyprogesterone concentrations (r = 0.81; P < 0.0001), but not with integrated cortisol concentrations. There was a significant negative correlation between cortisol and 17-hydroxyprogesterone at lag time 0 min (r = -0.187; P < 0.0001), peaking at lag time 60 min (r = -0.302; P < 0.0001), with cortisol leading 17-hydroxyprogesterone by these time intervals. Finally, 0800 h serum ACTH concentrations were sufficiently suppressed after a dexamethasone dose of 0.3 mg/m(2) in all but three patients. These findings indicate that in classic 21-hydroxylase deficiency, hydrocortisone should be administered during the period of increased hypothalamic-pituitary-adrenal axis activity, between 0400-1600 h, with the biggest dose given in the morning. Blood investigations performed as part of monitoring of congenital adrenal hyperplasia patients should include androstenedione and 17-hydroxyprogesterone concentrations determined in the morning before the administration of hydrocortisone. It should also be emphasized that blood investigations are only complementary to the overall assessment of these patients, which is primarily based on the evaluation of growth and pubertal progress.

Molecular and structural analysis of two novel StAR mutations in patients with lipoid congenital adrenal hyperplasia.

Mutations in the gene encoding steroidogenic acute regulatory protein (StAR) cause lipoid congenital adrenal hyperplasia. We report a novel homozygous splice site mutation (IVS1 + 2T --> G) in STAR in two sisters (46XY, 46XX) who presented with primary adrenal insufficiency at birth and a novel homozygous R182H missense mutation in the putative lipid transfer domain of StAR in a phenotypic female (46XY) with adrenal failure and a parotid tumor. These cases highlight the importance of StAR-dependent steroidogenesis during fetal development and early infancy and of the critical functional role of R182 in cholesterol transport.

Congenital adrenal hyperplasia: management during critical illness.

BACKGROUND: Little is known of the optimal dose and administration schedule of hydrocortisone in critically ill patients with congenital adrenal hyperplasia (CAH) caused by 21-hydroxylase deficiency. AIM: To determine plasma cortisol concentrations after intravenous administration of hydrocortisone in children with CAH and to relate these to plasma cortisol concentrations achieved by endogenous secretion in the stress of critical illness in previously healthy children. METHODS: Plasma cortisol concentrations were measured in 20 patients with classical CAH (median age 11.2 years, range 6.1-16.4) following intravenous administration of hydrocortisone 15 mg/m(2); and in 60 critically ill mechanically ventilated children (median age 2.5 years, range 0.25-16.3) on admission to the paediatric intensive care unit and for 24 hours thereafter. RESULTS: In the CAH patients, plasma cortisol reached a mean peak of 1648.3 nmol/l (SD 511.9) within 10 minutes of the intravenous bolus, and fell rapidly thereafter; levels remained greater than 450 nmol/l for 2.5 hours only. In critically ill children, mean plasma cortisol on admission to the intensive care unit was 727 nmol/l (SD 426.1). Cortisol concentrations remained raised during the first 24 hours. CONCLUSIONS: Critically ill patients with classical CAH may be best managed with a single intravenous hydrocortisone bolus followed by a constant rate infusion of hydrocortisone.

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency: alterations in cortisol pharmacokinetics at puberty.

In congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency, treatment with glucocorticoid and mineralocorticoid substitution is not always satisfactory. Suboptimal control is often observed in pubertal patients, despite adequate replacement doses and adherence to treatment. We investigated whether the pubertal process is associated with alterations in cortisol pharmacokinetics resulting in a loss of control of the hypothalamic-pituitary-adrenal axis. We determined the pharmacokinetics of hydrocortisone administered iv as a bolus. A dose of 15 mg/m(2) body surface area was given to 14 prepubertal (median age, 9.4 yr; range, 6.1--10.8 yr), 20 pubertal (median, 13.5 yr; range, 10.6--16.8 yr), and 6 postpubertal (median, 18.2 yr; range, 17.2--20.3 yr) patients with salt-wasting CAH. All patients were on standard replacement therapy with hydrocortisone and 9 alpha-fludrocortisone. Serum total cortisol concentrations were measured at 10-min intervals for 6 h following iv hydrocortisone bolus and analyzed using a solid-phase RIA. The serum total cortisol clearance curve was monoexponential. Mean clearance was significantly higher in the pubertal group (mean, 427.0 mL/min; SD, 133.4) compared with the prepubertal (mean, 248.7 mL/min; SD, 100.6) and postpubertal (mean, 292.4 mL/min; SD, 106.3) (one-way ANOVA, F = 9.8, P < 0.001) groups. This effect persisted after adjustment for body mass index. The mean volume of distribution was also significantly higher in the pubertal (mean, 49.5 L; SD, 12.2) than the prepubertal (mean, 27.1 L; SD, 8.4) patients but not in the postpubertal (mean, 40.8 L; SD, 16) (ANOVA, F = 15.2, P < 0.001) patients. The significance remained after correction for body mass index. There was no significant difference in mean half-life of total cortisol in prepubertal (mean, 80.2 min; SD, 19.4), pubertal (mean, 84.4 min; SD, 24.9), and postpubertal (mean, 96.7 min; SD, 9.9) patients. Similar differences between groups were observed when the pharmacokinetic parameters of free cortisol were examined. In addition, the half-life of free cortisol was significantly shorter in females compared with males (P = 0.04). These data suggest that puberty is associated with alterations in cortisol pharmacokinetics resulting in increased clearance and volume of distribution with no change in half-life. These alterations probably reflect changes in the endocrine milieu at puberty and may have implications for therapy of CAH and other conditions requiring cortisol substitution in the adolescent years.

Bioavailability of oral hydrocortisone in patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

The management of congenital adrenal hyperplasia due to 21-hydroxylase (CYP21) deficiency requires glucocorticoid substitution with oral hydrocortisone given twice or thrice daily. In paediatric practice little is known of the bioavailability of oral hydrocortisone tablets used in these patients. The aim of this study was to assess the bioavailability of oral hydrocortisone and to evaluate current replacement therapy in the light of cortisol pharmacokinetic properties. We determined the bioavailability of hydrocortisone following oral and intravenous administration in sixteen (median age: 10.9 years, range: 6.0-18.4 years) adequately controlled CYP21 deficient patients. Serum total cortisol concentrations were measured at 20-min intervals for 24 h while patients were on oral substitution therapy, and at 10-min intervals for 6 h following an intravenous bolus of hydrocortisone in a dose of 15 mg/m(2) body surface area. The area under the serum total cortisol concentration versus time curve (AUC) following oral and intravenous administration of hydrocortisone was calculated using the trapezoid method. The bioavailability was estimated by dividing the corrected for dose AUC after oral hydrocortisone administration by the corrected for dose AUC after the intravenous hydrocortisone administration and was exemplified as a percentage. After oral administration of hydrocortisone in the morning, median serum total cortisol concentrations reached a peak of 729.5 nmol/l (range: 492-2520 nmol/l) at 1.2 h (range: 0.3-3.3 h) and declined monoexponentially thereafter to reach undetectable concentrations 7 h (range: 5-12 h) after administration. Following administration of the evening hydrocortisone dose, median peak cortisol concentration of 499 nmol/l (range: 333-736 nmol/l) was attained also at 1.2 h (range: 0.3-3.0 h) and subsequently declined gradually, reaching undetectable concentrations at 9 h (5-12 h) after administration of the oral dose. After the intravenous hydrocortisone bolus a median peak serum total cortisol concentration of 1930 nmol/l (range: 1124-2700 nmol/l) was observed at 10 min (range: 10-20 min). Serum cortisol concentrations fell rapidly and reached undetectable levels 6 h after the hydrocortisone bolus. The absolute bioavailability of oral hydrocortisone in the morning was 94.2% (90% confidence interval (CI): 82.8-105.5%) whereas the apparent bioavailability in the evening was estimated to be 128.0% (90% CI: 119.0-138.0%). We conclude that the bioavailability of oral hydrocortisone is high and may result in supraphysiological cortisol concentrations within 1-2 h after administration of high doses. The even higher bioavailability in the evening, estimated using as reference the data derived from the intravenous administration of hydrocortisone bolus in the morning, is likely to reflect a decrease in the hydrocortisone clearance in the evening. Decisions on the schedule and frequency of administration in patients with congenital adrenal hyperplasia should be based on the knowledge of the bioavailability and other pharmacokinetic parameters of the hydrocortisone formulations currently available.

Kinetics and effect of percutaneous administration of dihydrotestosterone in children.

BACKGROUND: Percutaneous administration of dihydrotestosterone (DHT) has been successful in promoting phallic growth in infants and children with 5 alpha-reductase deficiency raised as males. We investigated whether percutaneous administration of DHT is similarly effective in patients with micropenis due to alternative diagnoses. METHODS: Six patients (age range 1.9-8.3 years) with micropenis of variable etiology were studied prospectively. 2.5% DHT gel was applied to the phallus once daily at a dose of 0.15-0.33 mg/kg body weight. Serum DHT concentrations were measured at 0, 2, 4, 8, 12 and 24 h following application of DHT gel. RESULTS: Peak DHT concentrations were attained within 2-8 h after application of the gel and subsequently remained within the normal adult range in all but 1 patient, who had received the lowest dose of 0.15 mg/kg. An increase in phallic growth, ranging from 0.5-2.0 cm, was achieved after 3-4 months of treatment in all patients whose DHT concentrations were maintained within adult range. CONCLUSION: Percutaneous administration of DHT in a dose of 0.2-0.3 mg/kg once daily for a period of 3-4 months may be useful in the management of patients with testosterone biosynthetic defects, who have sufficient masculinization to warrant male sex assignment, or in patients with micropenis prior to reconstructive surgery.

The GH response to low-dose bolus growth hormone-releasing hormone (GHRH(1-29)NH2) is attenuated in patients with longstanding post-irradiation GH insufficiency.

OBJECTIVE: Previous studies have suggested that post-irradiation GH insufficiency results from a loss of GHRH secretion, since many patients were able to release GH following exogenous GHRH stimulation. However, supramaximal doses of GHRH were used and the response may decline with time after radiotherapy. We re-evaluated the GHRH dose-response curve in patients post cranial irradiation and in controls. DESIGN: Randomized controlled study. METHODS: Five adult male long-term survivors of childhood brain tumours (median age 21.8 years (18.4-26.7); 13.7 years (11.4-15.7) post-radiotherapy, >30Gy) and five matched controls were studied. An intravenous bolus of GHRH(1-29)NH(2) was administered in doses at the lower (0.05 microg/kg) and upper (0.15 microg/kg) range of the dose-response curves for young males, as well as the standard supramaximal dose (1. 0 microg/kg). GH was measured before stimulation, every 2min for the first hour and every 5min for the second hour. All studies were conducted in a random fashion. RESULTS: Significantly lower peak and area under the curve (AUC) GH concentrations occurred in the irradiated group using 0.15 microg/kg (median peak Irradiated, 4. 5mU/l vs median Controls, 37.4mU/l; P<0.01) and 1.0 microg/kg (median peak Irradiated, 4.8mU/l vs median Controls, 15.2mU/l; P<0. 05) GHRH(1-29)NH(2). In irradiated subjects there was an incremental rise in GH output with increasing doses of GHRH(1-29)NH(2 )(median AUC: 122mU/l.min vs 179mU/l.min vs 268mU/l.min; P=0.007) reflecting altered pituitary sensitivity and reduced responsiveness. CONCLUSION: The GH response to bolus GHRH(1-29)NH(2) is attenuated in adult long-term survivors of childhood brain tumours. This may reflect direct pituitary damage and/or the loss of the tropic effects of chronic GHRH deficiency.

Frasier syndrome, part of the Denys Drash continuum or simply a WT1 gene associated disorder of intersex and nephropathy?

Dysfunction of the Wilms' Tumour gene (WT1), a transcription factor critical for normal development and function of the urogenital tract, can result in both tumourigenesis [corrected] and urogenital abnormalities. The association of WT1 gene mutations with most cases of Denys-Drash syndrome is well described. More recently WT1 mutations have also been described in a related condition, Frasier syndrome. We report a case where genetic analysis showed a WT1 mutation typically associated with Frasier syndrome: a 1228 + 5 guanine to adenine substitution at the 3' alternative splice donor site in intron 9. The case provides a focus for the discussion of recent evidence that Denys Drash and Frasier syndrome form two ends of a spectrum of disorders. In addition, it illustrates the increasing significance of genetic investigation within clinical practice for diagnostic, prognostic and therapeutic purposes and the importance of karyotype analysis in phenotypically normal girls with renal disease.

Blood pressure and Turner syndrome.

INTRODUCTION: Elevated blood pressure (BP) is an important predictor of morbidity and mortality from cardiovascular disease. Patients with Turner syndrome (TS) have a higher morbidity and mortality in middle age than the normal population. As BP in childhood or early adulthood is predictive of BP later in adult life, we assessed manual and 24 h ambulatory BP in patients with TS to determine whether the BP pattern is altered at an early stage in these patients who are known to be at risk of cardiovascular disease. PATIENTS AND METHODS: We studied manual and 24 h ambulatory BP profiles in 75 girls with Turner syndrome, age range 5.4-22.4 years. A monitor with an oscillometric device (SpaceLabs model 90207) and an appropriate sized cuff was used. BP was measured during the day-time (0800-2000 h) and the night-time periods (2200-0800 h). The BP measured were compared with population standards. The effect of different growth promoting agents on BP was also evaluated. RESULTS: Mean manual and 24 h ambulatory BP measurements were 118/77 mmHg (range 95/60-140/102) and 115/70 mmHg (range 93/57-154/99), respectively. There was minimal difference between the two methods with a positive bias of 2.4 mmHg for diastolic BP and a negative bias of 2.1 mmHg for systolic BP. The mean standard deviation scores (SDS) corresponding to the mean BP recordings were 24 h systolic + 0. 81 (range - 1.26 to + 4.45), 24 h diastolic + 0.43 (range - 0.85 to + 3.42), day-time systolic + 1.08 (range - 0.95 to + 4.72), day-time diastolic + 0.70 (range - 0.94 to + 3.71), night-time systolic + 0. 22 (range -2.2 to + 3.64) and night-time diastolic - 0.18 (range -2. 0 to + 2.43). The SDS for both the mean 24 h and day-time systolic and diastolic BP were shifted to the right of the normal distribution. 57% of the girls had less than the normal 10% reduction in nocturnal systolic blood pressure. 17% had diastolic and 21% had systolic blood pressure above the 95th percentile for age and sex. There was no significant difference in the BP SDS between girls on no treatment and those receiving treatment. CONCLUSION: Over 50% of girls with Turner syndrome have an abnormal BP circadian rhythm, which is similar to adult patients with secondary hypertension. Patients with Turner syndrome have higher blood pressure measurements compared to published population standards, as evidenced by the shift to the right of both the systolic and diastolic BP SDS. These findings suggest that girls with Turner syndrome should be carefully monitored in childhood and adulthood for blood pressure and other cardiovascular risk factors.

The influence of renal and cardiovascular abnormalities on blood pressure in Turner syndrome.

INTRODUCTION: Patients with Turner syndrome (TS) are at an increased risk of morbidity and mortality from cardiovascular disease. This study was undertaken to establish the prevalence of hypertension in patients with TS and to establish to what extent cardiovascular or renal abnormalities contribute to the measured blood pressure. PATIENTS AND METHODS: 62 patients with TS, age 5.4-22.4 years, had 24 h-ABPM (ambulatory blood pressure monitoring), echocardiography, renal imaging and measurement of recumbent plasma renin activity (PRA). Blood pressure was compared with population standards. RESULTS: 21% of the TS study population had mean systolic and 17% mean diastolic 24 h-ABPM measurements above the 95th percentile for age and sex (i.e. mild hypertension). Borderline blood pressure (i.e. 90th to 95th percentile) was found in another 17% of the patients. 57% of the patients had a blunted (i.e. less than 10%) fall in the night-time blood pressure. 24% of the patients had a detectable cardiac abnormality, 42% a detectable renal abnormality and 52% were found to have raised plasma renin activity. The presence of a cardiac or renal abnormality had no significant effect on blood pressure. Blood pressure of patients on growth and/or pubertal therapy was not different from those patients on no such treatment. CONCLUSION: Over 30% of patients with Turner syndrome were found to be mildly hypertensive and over 50% had an abnormal diurnal blood pressure profile. In this study we were unable to demonstrate that the presence of renal or cardiac abnormalities had an effect on recorded blood pressure. The use of growth hormone and oestrogen to manage growth failure and pubertal delay did not seem to affect blood pressure. This study suggests that there is a high prevalence of raised blood pressure in Turner syndrome patients. The 24 h-ambulatory blood pressure monitoring profile suggests that this may be secondary in origin, but we were unable to demonstrate an underlying mechanism with the renal and cardiac investigations performed.