Carbohydrate complexity and proportions of serum FSH isoforms in the male: lectin-based studies

FSH is synthesized and secreted in multiple molecular forms with different oligosaccharide structures which are needed for full expression of biological activity. GnRH and sex steroids modulate oligosaccharide structure and composition. In the present study we have assessed the carbohydrate complexity and proportion of circulating FSH isoforms during puberty, aging and after androgen administration to pubertal anorchid boys. Preparative isoelectrofocusing and lectin chromatography were used to isolate FSH isoforms on the basis of charge and internal carbohydrate complexity. Differences in sialic acid content and a progressive increase of isoforms bearing highly branched oligosaccharides were found during puberty. Less acidic, more bioactive FSH isoforms, secreted at mid-puberty may modulate important maturational events in the Sertoli cell population. Androgen administration to pubertal anorchid boys favoured the secretion of this type of isoforms. In adult men, the predominance of FSH isoforms bearing complex type oligosaccharides remained unchanged until very advanced age. These results show that the predominance of FSH isoforms bearing fully processed oligosaccharides in circulation may contribute to the development and maintenance of seminiferous epithelium function in men.

Neonatal screening program for congenital adrenal hyperplasia: adjustments to the recall protocol

OBJECTIVE

To evaluate the influence of gestational age (GA) and birth weight (BW) on 17 alpha-OH-progesterone (17-OHP) levels with respect to their impact on the recall rate of neonatal screening programs for congenital adrenal hyperplasia (CAH).

PATIENTS AND METHODS

In June 1997 we began a pilot screening program for CAH measuring 17-OHP using a fluoroimmunoassay method (DELFIA) on dried blood spots. Until September 1999, 24,153 babies were screened. Among them, we analyzed the levels of 17-OHP in 1,313 samples from healthy preterm babies (23-36 weeks) and 1,500 term babies (>37 weeks), grouped according to GA and BW. All preterm babies underwent another sampling in their 2nd week of life.

RESULTS

5 CAHs were detected. The 30-nmol/l cutoff limit for 17-OHP in blood corresponded to the calculated 99th percentile in term newborns, while in preterm babies higher levels were found. GA and BW correlated inversely with 17-OHP levels.

CONCLUSION

GA and BW were useful tools to adjust cutoff levels, obtaining a significant reduction in follow-up testing and psychological stress for families. The high false-positive recall rate in preterm babies can be substantially lowered with adjusted GA and/or BW criteria.

Role of inhibins in childhood and puberty

Inhibins, produced mainly in the gonads, suppress FSH synthesis. The bioactive dimeric forms of inhibin (A and B) have been proposed as peripheral markers of Sertoli and granulosa cell function. The determination of serum dimeric inhibins from birth through adulthood reflects a distinct pattern of both inhibins in males and females. Concomitantly with the gonadotrophin surge, an important production of inhibin B is observed during the first months of life. In males, inhibin B levels are higher than in females and persist elevated up to childhood, whereas in females they decrease up to prepubertal levels by 6 months of age. In girls, high serum levels of inhibin A are observed during the first two months of life; thereafter, they are undetectable until puberty. An active secretion of inhibin B persists in both males and females in the period of maximal LHRH pulse generator restraint; however, the possible gonadotrophin dependence of this production remains controversial. At puberty, a progressive rise in serum inhibin B occurs concomitantly with the increased production of sex steroids in both males and females. A similar secretion pattern of inhibin A is observed in girls. This increment is mainly exerted by gonadotrophins and modulated by multiple paracrine/autocrine mechanisms within the ovary and the testis that regulate the dimerization of the inhibin subunits throughout pubertal maturation. The differences observed in males and females between circulating dimeric inhibins in relation to gonadotrophins and sex steroid concentrations from birth through puberty has opened a new perspective for research in human reproduction. These new markers may contribute to a better knowledge of the regulation of the hypothalamic-pituitary-gonadal axis function and the physiopathology of the mechanisms involved in sexual differentiation and/or fertility disorders.

Usefulness of thyroxine and free thyroxine filter paper measurements in neonatal screening for congenital hypothyroidism of preterm babies

INTRODUCTION

Low thyroxine (T4) with normal thyroid stimulating hormone (TSH) is a well known condition in preterm (PT) infants. The establishment of T4 and freeT4 (FT4) values in filter paper dried blood spots in PT could provide useful information in the neonatal period.

OBJECTIVE

To study T4 and FT4 levels in dried blood filter paper samples of PT and full term (FT) babies.

METHODS

We measured T4 by fluoroimmunoassay (FIA) DELFIA and TSH by IFMA DELFIA (Wallac Inc Turku, Finland) in 193 PT (26 to 37 weeks of gestational age (GA)) in samples from the first and second week of life and in 153 FT babies in the first week of life. In 131 PT and 31 FT we determined FT4 in filter paper blood spots using FIA (Alonso Fernandez J). Infants were grouped according to GA.

RESULTS

There was a significant difference in T4 between PT and FT (p < 0.001). The lowest T4 levels were at 26 to 29 weeks GA. T4 values were lower in the second week. FT4 in PT up to 35 weeks GA, during the first week, was significantly different with FT infants (G1 to G3 p < 0.01, G4 p < 0.05). FT4 values in the first and second weeks of life did not vary.

CONCLUSIONS

T4 values were significantly lower in PT than in FT neonates, increasing with GA. PT infants had low T4 with normal FT4 values. This could suggest a decreased thyroxine binding globulin (TBG) or decreased protein binding and/or an adaptative mechanism that would not require therapeutical intervention.

Nocturnal TSH surge and TRH test response in the evaluation of thyroid axis in hypothalamic pituitary disorders in childhood

We studied, by means of TSH nocturnal secretion and TRH test, 42 children (4.2-19.9 years) with hypothalamic pituitary disorders and 24 healthy euthyroid children (5.7-15.4 years) as control group. Patients were divided according to their serum values of FT4 in group 1 (n = 27) with FT4 >/=10.3 pmol/l and group 2 (n = 15) with FT4 <10.3 pmol/l. TSH was measured by immunoradiometric assay. TSH nadir, TSH peak and TSH surge were calculated. Both groups differed significantly from control group in TSH surge values: group 1 (p < 0. 05), group 2 (p < 0.01). TRH test was abnormal in 11/27 patients of group 1 and 10/15 patients of group 2. In group 1, 7 patients had normal tests, 2 had abnormalities in both tests, 9 had only TSH nocturnal surge altered and 9 showed only TRH alterations. All patients of group 2 presented thyroid axis abnormalities. In conclusion, in patients with hypothalamic pituitary disorders with low FT4, no further investigation is required to demonstrate thyroid axis alterations, however in patients with normal FT4, nocturnal TSH secretion and TRH test may be required to evidence thyroid abnormalities.

Psychosocial outcome in growth hormone deficient patients diagnosed during childhood

Social disabilities have been described in GHD patients. The aim of this study was to evaluate the social outcome of a group of adult hypopituitary patients diagnosed and treated during childhood. Seventy patients were interviewed at a mean age of 25.6 years (range 18-50 yr). They answered a semistructured questionnaire and the Beck Depression Inventory test. Patients were compared for academic achievement, marital status and employment with the nearest age sibling. We found high levels of school repeaters, school was often not completed, and around 50% were overprotected by teachers and teased by peers. 32% were unemployed, while 58% of those employed work with their families. 80% still live with their parents; only 16% are married and 9% have children. 44% had no dating experience and 52% had never had sexual intercourse. Depression was common, especially in hypogonadic subjects. Juvenilization was the most common complaint. We did not found differences in maximal educational achievements and levels of employment between patients and siblings, but significantly more married siblings were found. Depression, social isolation and dependent life style were found in GHD patients. Appropriate medical and psychological counseling should be included for patients and their families as part of treatment.

Sexual dimorphism in circulating monomeric and dimeric inhibins in normal boys and girls from birth to puberty

BACKGROUND AND OBJECTIVE

Inhibins are peptides, mainly of gonadal origin, that suppress FSH production. Dimeric forms of inhibin (A and B) have been proposed as peripheral markers of Sertoli and granulosa cell function. The aim of this study was to establish the relationship between circulating dimeric and monomeric inhibins, and gonadotrophins and sex steroids, in normal boys and girls from birth to puberty.

SUBJECTS

One hundred and forty-six normal children (females: 57; males: 89) were studied.

MEASUREMENTS

Serum LH and FSH were measured by an immunofluorometric assay. Serum oestradiol and testosterone were measured by radioimmunoassay. Serum inhibin A and B, and Pro-alphaC, were measured by specific two-site enzyme-linked immunosorbent assays.

RESULTS

In boys from birth to 6 months of age, the mean serum inhibin B concentration was as high (477 +/- 53.7 ng/l) as that found at puberty (400 +/- 70.2 ng/l). After the first year, inhibin B gradually decreased to reach its lowest concentration (153 +/- 23.6 ng/l) at age 4-6 years. At approximately age 10, it rose progressively to reach pubertal concentrations. Pro-alphaC showed a similar pattern but at lower concentrations. Inhibin A was not detected at any age. In girls from birth to 6 months, inhibin B levels (83.0 +/- 18.3 ng/l) were approximately 50% lower than those found at puberty (181 +/- 25.7 ng/l). After 6 months of age, these levels dropped (17.5 +/- 1.6 ng/l) and remained low until the prepubertal years. Thereafter, they increased to pubertal concentrations. The serum inhibin A concentration after birth (29.9 +/- 8.7 ng/l) was similar to that found at puberty (18.3 +/- 5.7 ng/l); after 6 months, it fell to undetectable levels until the prepubertal years.

CONCLUSION

The sex difference in serum levels of gonadotrophins is associated with sex differences in the levels and proportions of circulating dimeric and monomeric inhibins.

Characterization of serum SHBG isoforms in prepubertal and pubertal girls

OBJECTIVE

SHBG is a circulating glycoprotein that binds dihydrotestosterone, testosterone and oestradiol with high affinity and low capacity. In girls, serum concentrations of SHBG gradually decrease with age due to a true fall in concentration and not to a change in the binding characteristics. The aim of our study was to determine the pattern of serum SHBG isoforms in normal girls in early childhood (ECh), late childhood (LCh) and puberty (P).

SUBJECTS

Fifteen normal girls were studied. They were divided into three groups according to their age: ECh: 3.7 +/- 0.9 years (mean +/- SD, n = 5); LCh: 6.4 +/- 0.5 years (n = 5); and P: 13.4 +/- 1.5 years (n = 5).

METHODS AND MEASUREMENTS

Preparative isoelectric focusing was used to isolate SHBG isoforms according to their isoelectric point (pI). Three groups of isoforms were isolated: SI: pI 5.2-5.4; SII: pI 5.4-5.6 and SIII: pI 5.6-5.8. Steroid levels in serum were determined by RIA.

RESULTS

The relative distribution of SHBG isoforms (% of the total SHBG recovered, mean +/- SD) in the three groups of girls studied was: ECh: SI: 25.8 +/- 9.9, SII: 53 +/- 10.5 and SIII: 21.2 +/- 1.6; LCh: SI: 8.8 +/- 3.1, SII: 58.8 +/- 12.2 and SIII: 31.8 +/- 8.6; P: SI: non-detectable; SII: 51.6 +/- 12.6 and SIII: 48.4 +/- 12.6.

CONCLUSION

These results indicate that serum SHBG is more heterogeneous before puberty. A considerable proportion of acidic isoforms are present early in life; they decrease during the prepubertal period and disappear when sexual development is completed. After puberty the glycoprotein is more homogeneous and an important proportion of more basic isoforms is present. At puberty serum SHBG not only falls in concentration but also has an altered sialic acid content which modulates its circulating half-life.

Congenital adrenal hyperplasia and early newborn screening: 17 alpha-hydroxyprogesterone (17 alpha-OHP) during the first days of life

OBJECTIVE

Definition of upper limits for 17 alpha-hydroxyprogesterone (17 alpha-OHP) is important as its measurement is used in screening for congenital adrenal hyperplasia. This study aimed at investigating the cut off concentrations in relation to the day of sample collection.

METHODS

17 alpha-OHP concentration was determined in dried filter paper blood spots taken from cord blood and by heel pricking up to the sixth day of life. A sensitive fluoroimmunoassay (DELFIA) method was used. Samples from 1091 apparently health full term neonates were tested. Samples were separated according to the age of sampling.

RESULTS

The 17 alpha-OHP (nmol/l blood) (median and 97.5th centile) concentrations according to the age of sampling were: cord blood (n = 126) 123.7, 265.6; first day 0-6 hours (n = 30) 49.4, 80.3; 6-12 hours (n = 57) 42.7, 79.8; 12-18 hours (n = 58) 38.1, 62.7; 18-24 hours (n = 67) 28.8, 49.7; second day 24-36 hours (n = 51) 23.6, 43.3; 36-48 hours (n = 63) 19.9, 35.4; third day (n = 200) 10.6, 23.5; fourth day (n = 197) 8.8, 20.8; fifth day (n = 76) 6.4, 18.3; sixth day (n = 166) 6.6, 19.4.

CONCLUSION

Cord 17 alpha-OHP concentrations were very high as previously described, probably owing to steroid production by fetal adrenal glands. Therefore, cord blood is not useful for screening purposes. Thereafter there is a gradual decline in 17 alpha-OHP median concentrations. A cut off value of 30 nmol/l blood was useful in samples obtained after 48 hours of life. However, cut off values before 48 hours should be adjusted according to the sampling time.

Final height in long-term primary hypothyroid children

OBJECTIVE

We studied retrospectively the statural growth and bone maturation of 32 children with primary hypothyroidism in order to relate their final heights to their chronological ages, height deficits and bone ages at the beginning of treatment. Patients were grouped according to age when treatment was started: Group 1 (G1) (n = 17): (15 girls, 1 boy) 3.09 +/- 0.8 yr; Group 2 (G2) (n = 9): (7 girls, 2 boys) 9.1 +/- 1.2 yr, and Group 3 (G3) (n = 6): (5 girls, 1 boy) 13.58 +/- 1.13 yr. At diagnosis G1 and G2 were prepubertal and G3 children were in puberty. In 10 patients of G1, 7 of G2 and 6 (all) of G3 final height was compared with target height.

RESULTS

(SDS) Initial height: G1: -3.74 +/- 1.2; G2: -3.94 +/- 1.32; G3 -3.65 +/- 1. Height at onset of puberty: G1: -1.06 +/- 1.1; G2: -2.5 +/- 1.4. Height menarche stage 5: G1: -0.63 +/- 1.1; G2: -1.76 +/- 1.2; G3: -2.6 +/- 1.7. Final height: (whole group) G1: -0.85 +/- 0.91; G2: -1.6 +/- 1.3; G3: -2 +/- 1.5. Final height G1 (n = 10): -1.05 +/- 0.89; G2 (n = 7) 1.2 +/- 1. Target height G1 (n = 10): -1.22 +/- 0.78; G2 (n = 7): -0.8 +/- 1.2; G3 (n = 6): -1.07 +/- 1.5. Initial bone age: G1: -4.9 +/- 0.85; G2: -7.2 +/- 2.6; G3: -4.5 +/- 1.9. Bone age (onset of puberty) G1: -0.26 +/- 1.74; G2: -2 +/- 1.7; Bone age (menarche) G1: 0.09 +/- 0.6; G2: -0.5 +/- 0.6; G3: -0.76 +/- 0.82.

CONCLUSION

G1 and G2, prepubertal at diagnosis, reached a normal adult height with respect to target height; G3 did not, the difference being statistically significant (p < 0.04). Puberty plays a decisive role in the incomplete catch-up growth of longstanding hypothyroid patients.

Oral desmopressin treatment of central diabetes insipidus in children

To assess the efficacy of treatment with oral desmopressin (DDAVP), 20 patients, aged 5-20 y, with central diabetes insipidus were studied during 3 d of hospitalization and for 3 months at the outpatient clinic. At baseline the median rate of diuresis was 12.7 ml kg-1 h-1. Urinary output decreased significantly under treatment with an increase in urinary osmolality, normalization of plasma osmolality and absence of nocturia. Patients were discharged from hospital with a median dose of 500 micrograms d-1 (100-1200 micrograms d-1). An adjustment in dosage was necessary in seven patients during follow-up, resulting in a final dose of 600 micrograms d-1. Body weight and DDAVP doses (r = 0.75, p = 0.001) and body surface and DDAVP doses (r = 0.72, p < 0.001) were significantly correlated. The average dosage was 474 +/- 222 micrograms m-2 d-1 (mean +/- SD). The oral DDAVP treatment remained effective during the 3 months of follow-up. This therapy offers an alternative for the treatment of central diabetes insipidus in children.

Gonadotropin secretion in prepubertal normal and agonadal children evaluated by ultrasensitive time-resolved immunofluorometric assays

To analyze a possible gonadal effect on the control of gonadotropin secretion during the prepubertal period, we have measured the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) serum concentrations in children with primary gonadal failure (PGF). We measured them using an ultrasensitive immunofluorometric assay (IFMA) in a single daytime serum sample and compared the results with those obtained with a radioimmunoassay (RIA) technique. The patients were 22 children with PGF (13 girls and 9 boys) aged 0.56-15.4 years and 58 normal children (28 girls and 30 boys) aged 0.08-16 years. In the normal group there were significant changes in serum LH and FSH concentrations in relation to sex and pubertal development. These changes were more evident especially in LH concentrations when using IFMA. We observed that during the prepubertal period the normal LH levels (mean +/- SD) were detectable with this method at concentrations well below the limit RIA could detect (girls 0.026 +/- 0.012 IU/l, and boys 0.025 +/- 0.01 IU/l), while at the onset of puberty these LH levels rose significantly in both sexes (girls 1.0 +/- 0.79 IU/l, boys 1.7 +/- 0.7 IU/l; p < 0.01 vs. prepubertal group), reaching similar values to those observed in FSH concentrations (prepubertal girls 1.9 +/- 0.89 IU/l, boys 0.73 +/- 0.41 IU/l; early pubertal girls 3.1 +/- 0.9 IU/l, boys 2.6 +/- 1.3 IU/l). At prepubertal age, most PGF patients showed normal gonadotropin serum levels (particularly LH) when measured by RIA. However, these same samples-when measured by IFMA-showed LH and FSH levels clearly higher than normal in almost all-10 of 12-patients (PGF girls, n = 8, LH 1.1 +/- 1.0 IU/l, FSH 34 +/- 30 IU/l; PGF boys, n = 4, LH 0.13 +/- 0.12 IU/l, FSH 6.5 +/- 5.7 IU/l). We conclude that, during the so-called 'juvenile pause' when the gonadotropin concentrations could be reliably measured, supranormal gonadotropin levels could be observed during a single daytime serum sample in patients with PGF. These findings suggest that during this period of life the gonads contribute to the negative feedback regulation of gonadotropin levels.

Persistence of autonomous ovarian activity after discontinuation of therapy for precocious puberty in McCune-Albright syndrome

OBJECTIVE

The aim of this study was to evaluate the possibility of persistence of autonomous ovarian activity in girls with McCune-Albright syndrome (MAS) after withdrawal of medroxyprogesterone therapy administered for precocious puberty.

DESIGN, SETTING, AND PARTICIPANTS

Five girls with MAS were followed-up 1.2 to 8.5 years after the end of treatment. The girls underwent luteinizing hormone-releasing hormone (LH-RH) tests, estradiol (E2) basal measurement, and pelvic ultrasound two times in the follow-up period.

RESULTS

Menses resumed in four of five girls, 1.4 +/- 0.9 years after the end of treatment, at chronologic age of 11.3 +/- 1.3 years. Cycles for all girls were irregular. Three patients presented inadequate E2 levels (from 56 to 320 pg/mL) associated with low or absent gonadotropin response to LH-RH tests. The pelvic ultrasound showed ovarian cysts at the time of the study.

CONCLUSION

These hormonal and ultrasonographic findings provide evidence of persistence of autonomous ovarian activity in some young women with MAS.

Molecular analysis of sex determination in sex-reversed and true hermaphroditism

The SRY (sex region of Y) gene determines testis formation but not all cases of sex reversal in humans can be explained by alterations in this gene. We studied one 46,XY female, four 46,XX males, and nine true hermaphrodites (TH): three with an XY and six with an XX chromosomal constitution. The SRY gene was identified in the XX males and the TH with a Y chromosome but was not demonstrated in the XY female and the six XX TH. The Y-heterochromatin region was also identified in one 46,XX male, indicating a low grade mosaicism undetected by cytogenetics. The amplification of the amelogenin gene showed the presence of a 977-bp band that belongs to the short arm of chromosome X in all patients but the absence of a 780-bp band of the short arm of chromosome Y in three 46,XX males and in all the 46,XX TH. These studies demonstrate that the molecular study of sex-reversed patients and TH will help to understand the complex mechanisms of sex determination. The SRY gene is involved but other genes on the X chromosome and autosomes still remain to be studied.

Functional adrenal cortical tumors in pediatric patients: a clinicopathologic and immunohistochemical study of a long term follow-up series

BACKGROUND

Controversy exists as to which variable is a reliable predictor of clinical outcome of adrenal cortical tumors in children.

METHODS

Twenty patients with adrenal cortical tumors were studied. Tumor weight, histologic features, and percentage of proliferating cell nuclear antigen (PCNA/cyclin) in tumor cells were analyzed to determine the best predictor of clinical outcome.

RESULTS

Eleven patients had Cushing's syndrome with virilization and 9 had virilization without Cushing's syndrome. The mean age at diagnosis was 7.1 +/- 5.2 years (range, 0.4-15.6 years). Sixteen patients, with good outcomes have been followed for 10.7 +/- 7.8 years (range, 3-23 years). All but two patients had a tumor weight of less than 100 g (185 g and 800 g, respectively) (mean 47.7 g +/- 46.4 g). Two patients with large tumors (weighing 1000 g and 780 g, respectively) had poor outcomes; 1 died 3 months after surgery with metastasis and the other presented with lung metastasis 18 months after surgery. Histologic features did not correlate with clinical outcome. Overall, PCNA stained cells were 6.96 +/- 8.2% (range, 0-32.5%). PCNA values were significantly lower in tumors of patients with good outcomes (P < 0.002). Within all tumors, we found a weak correlation between tumor weight and PCNA (r = 0.51; P < 0.02), but a better correlation was found between tumor weight and PCNA in patients with Cushing's syndrome (r = 0.70; P < 0.01). Patients with Cushing's syndrome had higher PCNA values than those with virilization syndrome (10.3 +/- 9.6% vs. 2.8 +/- 3.3%; P < 0.03).

CONCLUSIONS

Our data show that small tumors (less than 100 g) are associated with good outcome; the two patients with the poorest prognosis had Cushing's syndrome and large tumors (more than 100 g). Histologic features are not adequate predictors of outcome and PCNA may be useful in tumors of patients with Cushing's syndrome, but this parameter should not be used alone. Two patients had virilization syndrome, large tumors (185 g and 800 g, respectively), and good outcomes, which contradicts with the concept that these tumors are usually associated with poor prognosis.

Reproducibility and comparison of growth hormone secretion tests

To assess the degree of reproducibility of spontaneous GH secretion and pharmacological tests we studied 15 prepubertal children with short stature and abnormal growth rate. In all children, spontaneous overnight GH secretion was measured followed by a clonidine test in 8 children and an arginine test in the remaining 7. The same protocol was repeated a week later. Intra-individual variability of GH secretion in both physiological and pharmacological tests was expressed as the coefficient of variation (CV%). No significant difference was found between the first and second value of parameters of spontaneous GH secretion. Maximum spontaneous GH peak (MS) and mean 12-h GH concentration (MGH) correlated significantly (r = 0.78, p < 0.001). Mean CV% of all parameters of repeated GH profiles (around 30%) were lower than those of provocative tests (around 70%) (p < 0.05). No significant difference was found between CV% of clonidine and arginine tests. There was no correlation between MGH or MS and GH response to provocative test in the same child. We found a significant correlation between the log transformed maximum provocative GH response to the arginine test and the length of the time interval (in min) from the end of the last GH peak in the previous profile to the time zero of the provocative test (r = 0.60, p < 0.05). This relationship was not found for the clonidine test. We conclude that spontaneous GH secretion in children with short stature is more reproducible than stimulated GH response with a week's difference. Perhaps the higher variability of provocative GH secretion may be related to the state of the endogenous hypothalamic rhythm of both GHRH and somatostatin release at the time of the test.

Growth of Argentinian girls with Turner syndrome

Growth data on 254 patients with Turner syndrome from Argentina-120 with XO karyotype and 134 with other chromosomal abnormalities-were analysed. Birth weight and height were significantly reduced. Ninety patients had received oestrogen treatment from a mean age of 14-0 years (SD 1.2) and 17 patients had spontaneous menarche. Patients who underwent spontaneous menarche had a small growth spurt. Final height was slightly higher (139.8 cm SD 5.6), though not significantly different from the mean adult height of the whole sample (137.9 cm SD 5.7). Mean adult height was 3.73 SD below mean of the normal local population. Mean height velocities from birth to maturity are very similar to those found in other samples. Distance standards were prepared by fitting a fifth-degree polynomial to the interpolated mean heights at each 0.5 year of age, and to the raw SD. Selected centiles were then calculated from the smoothed values. Differences between adult height in local Turner syndrome girls and local normal population are very similar to the same Turner-normal differences described in other communities. Standards presented here are useful for evaluating Turner syndrome patients from Argentina, and may also be used by those with similar growth pattern in their normal population.

Long term treatment with low dose testosterone in constitutional delay of growth and puberty: effect on bone age maturation and pubertal progression

We compared the effects of long term low dose treatment with testosterone on pubertal growth and sexual development in boys with constitutional delay of growth and puberty (CDGP). We treated 24 boys with intramuscular monthly injections with low dose testosterone enanthate (33-50 mg) for 20 months, at a chronological age of 14.5 +/- 1.0 years and SDS height of -3.31 and compared their response to a group of 14 control boys. Treated patients showed an earlier and significant increase in height velocity compared to controls, 10.1 vs 4.0 cm/year, while the latter group showed their growth spurt twelve months later. Both groups showed an initial acceleration in bone age without impairment of predicted adult height. During the first 12 months of treatment the increment of testicular volume in the treated patients was slightly slower than controls; however the earlier the puberty, the slower the testicular increment compared to controls. We conclude that treatment of boys with constitutional delay of growth with low dose testosterone is effective in improving their height velocity without impairment of predicted final height. Progression of testicular volume during treatment in some patients is more delayed; however, after treatment it increased normally.

Bone age at discontinuation of medroxyprogesterone acetate therapy in girls with precocious puberty: effect on final height

To determine the final height of patients with precocious puberty treated with medroxyprogesterone acetate (MPA; 150 mg every week) for a period > 1 year (mean +/- SD = 3.24 +/- 1.85 years), data from a group of 26 girls were analyzed. The attained final height was 155.6 +/- 8.06 cm (-1.1 SD of the normal population). In a group of 8 untreated girls with precocious puberty, adult height was 149.2 +/- 5.07 (-2.16 SD, p < 0.02). In 9 patients in whom treatment was stopped at a bone age < or = 12 years, final height was 159.2 +/- 10.05 cm, while in 16 girls who had a bone age > 12 years at the end of treatment, the final height was 153.03 +/- 6.28 cm. Our data demonstrate the effectiveness of MPA treatment on ultimate height. The better height observed in those patients who stopped treatment with a bone age < 12 years suggests the advantage of discontinuing therapy before reaching a more advanced degree of skeletal maturation.

Isolation of human Leydig cell mesenchymal precursors from patients with the androgen insensitivity syndrome: testosterone production and response to human chorionic gonadotropin stimulation in culture

Mature Leydig cells, the main source of testicular testosterone in mammals, arise from immature mesenchymal precursors through an LH-dependent differentiation process. In order to study the steroidogenic potential of these precursors, undifferentiated mesenchymal cells were obtained from the testicular interstitium of two patients with androgen insensitivity syndrome. After double digestion with collagenase and separation of the suspensions in a Percoll density gradient, the cells were cultured in Ham's F12 medium: Dulbecco's Modified Eagle Medium (1:1) supplemented with antibiotics, transferrin, insulin, hydrocortisone, and vitamin E with or without 1 IU of hCG/ml. At 11 days in culture, samples were removed for morphological characterization and determination of 3 beta-hydroxysteroid dehydrogenase activity (3 beta-HSD). Testosterone concentration was determined by RIA in the culture medium at different intervals. Cultured cells were mesenchymal in appearance, elongated in shape, with numerous processes running in different directions. No mature Leydig cells were present. In basal conditions, the percentages of 3 beta-HSD-positive cells at 11 days on patients 1 and 2 were 33% and 28%, respectively, and the testosterone concentrations in the culture media were 4.8 and 8.4 ng.10(6) cells.24 h, respectively. In cultures stimulated with hCG, there was an increase of histochemical reactivity (47% and 42% in patients 1 and 2, respectively) and in the amount of testosterone secreted (10.2 and 12.0 ng.10(6) cells, respectively). Electron microscopic studies of cultures grown in the absence of hCG demonstrated a homogenous population of poorly differentiated, fibroblastic-type mesenchymal cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone mineral density of the spine and radius shaft in children with X-linked hypophosphatemic rickets (XLH)

X-linked hypophosphatemic rickets (XLH) is characterized by inadequate skeletal mineralization. The bone mineral density (BMD) of the radius shaft and the lumbar spine was determined in 13 children with XLH. Ten patients were on treatment, whereas three patients had discontinued treatment 20-32 months prior to this study. Two of them had radiological evidence of rickets. The radius shaft BMD was significantly diminished: Z score was -1.33 +/- 0.89 (P less than 0.001), while the BMD of lumbar spine was significantly augmented (Z score +1.95 +/- 1.17, P less than 0.001). A positive correlation was found between the Z scores for the BMD of the radius shaft and spine. The two patients with overt rickets had lower radius shaft BMD values and a lesser increment of BMD of the spine. The BMD deficit of cortical bone may be related to the lack of efficacy of the treatment and/or to an intrinsic defect of the bone on this disease. On the other hand, the augmented BMD of the lumbar spine might reflect the overabundance of partially mineralized osteoid. The determination of the BMD of the radius shaft by SPA was a sensitive method for detecting abnormalities of the bone mass in XLH patients under treatment without radiological signs of rickets.

Pubertal development in male hypopituitarism

The spontaneous or therapeutically induced pubertal development of 65 male patients with idiopathic hypopituitarism was analysed. Spontaneous puberty occurred in 82% of the patients with prepubertal isolated growth hormone deficiency and in 32.5% of those with impairment in the secretion of more than one pituitary hormone. Out of this group, 36 patients could be studied longitudinally. In 15 patients, the onset of spontaneous puberty was delayed, on average, 3.2 years. It started at a bone age of 10.36 +/- 1.25 "years" and followed a pattern similar to that of normal boys. Testosterone levels at each pubertal stage were not different from those of normal boys. Mean peak height velocity reached 7.27 +/- 1.82 cm/year. In 21 patients with gonadotropin deficiency, hCG treatment was started at a chronological age of 19.04 +/- 2.17 years and a bone age of 12.94 +/- 0.80 "years". Plasma testosterone attained normal adult levels in the majority of boys, while the development of sexual characteristics showed a wide variation. Mean growth velocity during the first year of hCG therapy reached 6.11 +/- 2.47 cm/year. Partial gonadotropin deficiency was diagnosed in two boys. Although testosterone seems today to be, for practical reasons, the replacement therapy of choice, hCG treatment is an alternative for hypopituitary patients with absent gonadotropin function.

Response to acute hCG stimulation and steroidogenic potential of Leydig cell fibroblastic precursors in humans

The process of early testosterone (T) secretion and Leydig cell differentiation in humans was studied to explore the steroidogenic capacity of Leydig cell fibroblastic precursors. Seven cryptorchid boys received hCG prior to orchidopexy. Patients CP, PB, and MR received one injection of 1000 IU; patients JR and GG, three daily injections of 1000 IU, and patients MP and MM, five daily injections of 1000 IU. A testicular biopsy was obtained at the time of operation, 24 hours after the last injection. Serum T (ng/dl) before and after hCG stimulation and testicular T (ng/g) were determined by RIA. A control prepubertal testis (tumoral orchidectomy) was incubated in vitro and showed a time-dependent accumulation of T both in the medium and the testicular tissue. Testosterone released into the medium at 1, 2, and 4 hours was 0.76, 1.43, and 4.03 ng/ml, respectively. Tissue T at 0, 1, 2, and 4 hours was 9, 11, 16, and 24 ng/g, respectively. This indicates synthesis and secretion of T into the medium. Control testes showed abundant fibroblastic precursors with scanty cytoplasm, few organelles, heterochromatic nuclei, and minute nucleoli. No Leydig cells were present. After 1 day of hCG stimulation, numerous fibroblasts were activated, displaying enlarged cytoplasms with increased numbers of organelles, nuclei rich in euchromatin, and bigger nucleoli. No Leydig cells were present. Basal serum testosterone was 58.2 +/- 45.3 ng/dl and 87.3 +/- 42.0 after hCG administration, while testicular T was 974.0 +/- 686.0 ng/g (control prepubertal testicular T is 10-50 ng/g). After 3 days of hCG, activated fibroblasts increased and immature Leydig cells appeared. Basal serum T was 35.5 +/- 7.8 ng/dl and 394.0 +/- 24.0 after hCG stimulation, while testicular T rose to 2797.5 +/- 1222.6 ng/g. After 5 days, mature Leydig cells appeared for the first time. Serum T was 58 +/- 59.3 ng/dl (basal) and 641.5 +/- 390 ng/dl (after hCG); testicular T was 789 ng/g (patient MM did not have a value for testicular T). HCG induced numerous coated pits and endocytic vesicles in activated fibroblasts and young Leydig cells, suggesting receptor aggregation and internalization of hormone-receptor complexes. Peroxidase-antiperoxidase (PAP) localization of T was positive in peritubular fibroblasts and Leydig cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Comparison of single and combined tests for the evaluation of plasma growth hormone secretion in normal short children

Growth hormone (GH) response to provocative tests was compared in normal short children. Seven of 23 children failed to respond to insulin hypoglycemia. Using insulin hypoglycemia followed by L-dopa only 2 of 23 children did not respond and giving bromocriptine combined with insulin hypoglycemia only 1 of 8 children failed to respond. All children submitted to propranolol followed by exercise (n = 14) and to bromocriptine followed by exercise (n = 6) responded with a satisfactory increase in plasma GH levels. The increase elicited by propranolol and exercise was higher than that induced by insulin hypoglycemia alone (p less than 0.005), exercise alone (p less than 0.05) or L-dopa after insulin hypoglycemia (p less than 0.01). The rise of GH induced by bromocriptine and exercise was higher than that obtained with insulin hypoglycemia alone (p less than 0.05). This study suggests that both adrenergic and dopaminergic mechanisms are involved in exercise induced GH release and confirms that combined tests are more useful than a single test to evaluate GH secretion.

Steroid metabolism by a tumour of the specific gonadal stroma in a child

A study of steroid metabolism by a tumour of the specific gonadal stroma was carried out in a 10 year old boy. Tumours developed in the two testes from multiple foci, and clinically, no signs of sexual development were evident. Four testicular enzymes necessary for testosterone biosynthesis were estimated in the child, in two adult controls, and in three pre-pubertal boys with male pseudohermaphroditism but normal tests of Leydig cell function. 17 alpha-Hydroxylase and 17 beta-hydroxysteroid dehydrogenase were similar in the five controls and in the gonad with the tumour, while 17,20-desmolase and 3 beta-hydroxysteroid dehydrogenase were grossly deficient in the child with the tumour. These enzyme deficiencies might explain the absence of peripheral virilization in a boy with a tumour of Leydig and Sertoli cells.

Evaluation of short stature in children

Within a year 429 children referred for short stature have been evaluated. The age at consultation ranged from 5 months to 17 1/2 years. Healthy but small children came at 5 to 7 and 10 to 13 years, while those with different pathologies attended the clinic at all ages. The stature of 43% of the investigated children ranged within normal limits (till -2 SDS), while 57% had a small stature. 68% of the children could be considered healthy, 32% had different endocrine and nonendocrine diseases responsible for their growth retardation. Retarded bone age (greater than 2 SD below the mean) was observed in 65% of the significantly short but otherwise healthy children and in only 28% of the healthy children with heights above -2 SD. Extreme short stature was mainly associated with a recognized disease of chronic and genetic origin, low birthweight and malnutrition. The high incidence of hypopituitarism (15 patients) is due to the fact that this study was performed in an endocrine clinic.

Effects of alpha-bromoergocryptine on pituitary hormone secretion in children

The effect of bromoergocryptine (BE) on human GH (hGH), PRL, LH, FSH, TSH, and blood sugar levels was evaluated in a series of 22 normal children. Blood samples were collected in basal conditions and after 30, 60, 90, 120, 150, and 180 min of BE administration (1.25 or 0.62 mg/os). The drug induced a marked and sustained increase in hGH secretion when basal serum levels of the hormone were lower than 10.0 ng/ml (n = 15). When basal hGH serum levels were higher (n = 7), BE provoked either a later increase of serum hGH in most children (n = 5) or a persistent decrease in hGH (n = 2). On the other hand, BE markedly inhibited PRL secretion without modifying LH, FSH, or TSH. The data obtained suggest that BE can be used as a useful tool for the assessment of hGH secretion in children.

Effect of gonadotrophins and testosterone on the seminiferous tubules of the immature rat

The actions of HCG and PMSG for different periods and of testosterone of the immature rat testis were studied. Short-term administration of HCG (1-3 days) induced an early meiotic and postmeiotic stimulatory effect but a decrease in spermatogonial numbers. Administration of HCG for longer periods (10 days) caused a reduction in numbers of all cell types. Treatment with HCG + PMSG reduced the amount of inhibition, while PMSG alone resulted in histological and humoral signs of stimulation of the interstitial tissue and the meiotic and postmeiotic stages; the numbers of spermatogonia were not affected. Testosterone caused stimulation of the meiotic and postmeiotic stages and a reduced number of spermatogonia. It is concluded that while PMSG directly stimulates spermatogonia, HCG acts through testosterone secretion at the meiotic and postmeiotic stages. The early inhibitory effects of HCG and testosterone on spermatogonial numbers could be ascribed to the inhibition of endogenous FSH by androgens.

Effect of HCG on the interstitial cells and androgen production in the immature rat testis

The effect on the interstitial cells in the immature rat testis of administration of HCG for different periods was correlated with testosterone plasma levels. Significant and progressive stimulation of mitosis was observed after 3 days of HCG treatment but stabilization occurred after 5 days. The numbers of precursor fibroblasts had increased by the 5th day and were still increasing by the 10th day of treatment. Numbers of Leydig cells were significantly greater at 5 and 10 days of treatment. Plasma testosterone showed a progressive and continuous increase in all groups. The increase in Leydig cell number is considered to be due to a combination of increased stimulation of mitoses in Leydig cells and differentiation of precursor fibroblasts. Mitosis seems to precede fibroblastic differentiation, but the latter continues when mitotic changes have stabilized. The elevation of plasma testosterone concentrations is probably due firstly to the stimulation of the existing Leydig cells and then to the increase in the number of hormone-secreting cells.

Plasma concentration of oestradiol-17beta in premature thelarche and in different types of sexual precocity

Plasma Oe2 concentration was measured by radioimmunoassay in patients with premature thelarche, with precocious puberty and in 29 normal controls. The mean plasma Oe2 was 1.5 pg/ml (0-7.2) in normal prepubertal girls, 23.8 +/- 17.8 (SD) in pubertal girls, 50.2 (+/- 19.4) in the follicular phase, and 94.2 (+/- 19.5) in the luteal phase of normal adult females. Ten girls with premature thelarche had a mean of 7.7 +/- 6.6 pg/ml. Three of them showed higher values than the other 7, suggesting that in these cases, elevated levels of plasma Oe2 might have played a role in the development of breast tissue. Ten untreated girls with idiopathic precocious sexual development had a mean of 51.6 +/- 42.9 pg/ml while 6 patients treated with 150 mg per week of medroxyprogesterone acetate had a mean of 11.4 +/- 2.5 pg/ml. Two patients with Down's syndrome, hypothyroidism and sexual precocity had plasma Oe2 of 144 and 31.5 which fell to 24.7 and 8 pg/ml, respectively, after thyroid replacement. One girl with a granulosa cell tumour had a basal value of 304 pg/ml and a concentration of 27 pg/ml after surgery.

Gonadotropin secretion in prepubertal and pubertal primary hypogonadism: response to LHRH

Plasma LH and FSH were measured before and after LHRH administration in 10 patients with Turner's syndrome, in 7 with anorchia, in 2 castrates, in 18 with Klinefelter's syndrome, and in 11 prepubertal subjects with unilateral cryptochidism used as a control group. Basal LH was elevated in 4 and basal FSH in 8 of 10 patients with Turner's syndrome. Four patients with anorchia showed elevations of LH while FSH had increased in all of them. The two castrates had normal or slightly increased basal LH and definite elevations of FSH. Prepubertal subjects with Klinefelter's syndrome had normal plasma LH and FSH levels, but showed a marked elevation when they developed puberty. After LHRH administration, mean LH increased by 297% and FSH by 81% in Turner's syndrome, while in anorchia LH increased 757% and FSH 104%. After LHRH administration, patients with unilateral cryptorchidism had an LH increment of 316% and a FSH increment of 164%. Patients with prepubertal Klinefelter's syndrome showed elevations of 261% for LH and 221% for FSH after LHRH treatment. Adolescent subjects with Klinefelter's syndrome had an increment of 352% for LH and only 13% for FSH after LHRH administration. We have concluded that patients without functioning gonads fail to suppress gonadotropin secretion even before puberty while the gonads of the prepubertal Klinefelter's syndrome are able to control LH and FSH release. After puberty, in spite of the hypersection of LH and FSH observed in all subjects with agonadism there is a large pituitary reserve of the gonadotropins. We suggest that the relative inability of pubertal patients with Klinefelter's syndrome to increase FSH after LHRH treatment might be due to the presence of an abnormal compound secreted by the gonads.

Levels of plasma growth hormone in children with congenital heart disease

HGH plasma levels were studied in 45 children with different types of cyanotic and acyanotic congenital heart diseases with and without growth retardation. Median HGH levels in patients with normal height (Group I) were 5.2 ng/ml (range 0–50) and in patients with short stature (Group II) 7.2 ng/ml (range 0.6–50). No difference was found between these groups ("Z" = 1.33, P: non-significant). However on comparing the cyanotic and acyanotic patients regardless of the presence of growth retardation, HGH levels were significantly different (P < 0.01). The acyanotic group with an oxygen saturation of 94.4 % ± 1.7 (mean ± se) had HGH levels of 4.6 ± 0.7 ng/ml. The cyanotic group with an oxygen saturation of 69.5 % ± 4.4 had HGH levels of 23.3 ng/ml ± 3.5. An insulin test was performed in 5 patients with high HGH basal levels. Three showed an increase of HGH levels after insulin. In the other 2 patients the HGH levels remained high.

In conclusion growth hormone deficiency could be ruled out as a possible cause of growth retardation in children with congenital heart disease. It is suggested that hypoxia could induce HGH secretion. Tissue hypoxia and its effect on DNA metabolism could be a factor which regulates HGH production. Hypoxia could also stimulate anaerobic metabolism and the resultant metabolites bring about an increase in HGH release.

The testis in patients with abnormalities of sex differentiation. Histology and endocrine function

Testicular function was studied in 18 patients with abnormalities of sexual differentiation. Fourteen patients were prepubertal and four postpubertal. Plasma testosterone was determined before and after 5000 IU HCG administered daily during 5' days. Of the fourteen prepubertal patients, the two true hermaphrodites and the patient with asymmetrical gonadal differentiation showed a poor response to gonadotrophin stimulation. This could be explained by the small amount of active testicular tissue or its coexistence with ovarian and rudimentary gonadal tissue which might exert some influence on the endocrine function of the testis. In the group of eight patients with male pseudo-hermaphroditism and ambiguous external genitalia, the response to HCG showed a large variation. The three patients with small testes had lowest values i. e. 210, 198 and 192 ng/100 ml. The remaining five patients showed normal values ranging between 360 and 720 ng/100 ml. The ambiguous external genitalia of these patients could be explained as being due to a diminished androgen target organ sensitivity limited to the external genitalia. The three prepubertal patients with male pseudo-hermaphroditism and female external genitalia showed a marked increase in plasma testosterone with HCG ranging between 598 and 1100 ng/100 ml. The four pubertal cases also had high values in basal conditions, between 920 and 1870, which increased even more after gonadotrophin stimulation, in one case from 1382 to 2264 ng/100 ml. This hypersensitivity to exogenous HCG, even in infancy, correlates with the elevated basal values observed in adult patients with otherwise female external genitalia and androgen insensitivity. Finally, the HCG stimulation test could be useful for the demonstration of testicular tissue in prepubertal patient with abnormalities of sexual differentiation, although it cannot be used as a prognosis of masculinization or feminization at puberty.