Serum bioactive luteinizing and follicle-stimulating hormone concentrations in girls increase during puberty

The negative impact of levothyroxine treatment on urinary luteinizing hormone measurements in pediatric patients with thyroid disease

Objectives

Previous studies suggest urinary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measurements by immunofluorometric assays (IFMA) as noninvasive alternatives to serum assays for puberty assessment. However, these studies excluded patients with other endocrine disorders and those taking medications. Besides, the recent discontinuation of IFMA manufacturing is a concern. We explored the utility of luminometric assays (LIA) for urinary gonadotropins and thyroid-stimulating hormone (TSH) determinations in euthyroid patients with thyroid pathologies.

Methods

We used LIA and IFMA assays to measure serum and first-morning-voided (FMV) urine LH, FSH, and TSH concentrations in euthyroid patients with various thyroid disorders. Of the 47 euthyroid patients with normal serum TSH (S-TSH) levels, 14 were receiving levothyroxine therapy.

Results

FMV total urinary LH (U-LH) concentrations correlated significantly with those measured in serum using either LIA (r=0.67, P<.001) or IFMA (r=0.83, P=.003) in patients not receiving levothyroxine treatment; however, no significant correlation could be detected in patients receiving levothyroxine regardless of the assay method (for LIA: r=0.50, P=.08 and IFMA r=0.44, P=.15). Urinary TSH (U-TSH) concentrations correlated poorly with those in serum in both the untreated and the treated groups (r=-0.13, P=.49, and r=-0.45, P=.11, respectively).

Conclusion

FMV total U-LH determinations by LIA can be used to assess pubertal development in patients with thyroid pathology, provided the euthyroid patient is not on levothyroxine treatment. U-TSH measurements by LIA cannot replace invasive S-TSH measurements at least in patients with normal S-TSH levels. Further research may reveal the utility of U-TSH determinations in patients with elevated S-TSH levels.

Comparing adolescent self staging of pubertal development with hormone biomarkers

OBJECTIVES

Physical examinations to characterize pubertal maturation may be unacceptable for children enrolled in research studies. Studies confirm the utility of pubertal self staging for research, but there has been limited comparison of self examination with hormone biomarkers. Our objective was to assess concordance of pubertal self staging with hormone biomarkers of puberty.

METHODS

Participants were enrolled in the Health Outcomes and Measures of the Environment Study, a longitudinal pregnancy and birth cohort study. At age 12 years, 139 females and 112 males completed pubertal self staging including breast and pubic hair development in females and pubic hair development in males. No clinical physical examination was performed. Hormone concentrations were measured in 102 females and 96 males including serum dehydroepiandrosterone sulfate, luteinizing hormone, and follicle-stimulating hormone in all; estradiol in females; and testosterone in males.

RESULTS

Estradiol was significantly associated with female breast stage, even when adjusted for BMI, with geometric least squares means (95%CI) of 13.2 (8.7, 20.2), 38.3 (29.9, 49.1), 59.4 (39.8, 88.6), and 81.2 (45.6, 144) pg/mL for breast stage 1-2, 3, 4, and 5, respectively. Testosterone was significantly associated with male pubic hair stage, with adjusted geometric least squares means (95%CI) of 37.6 (19.9, 71.1), 43.4 (27.7, 68.3), 126 (78.4, 203), 275 (146, 521), and 559 (237, 1319) ng/dL for pubic hair stage 1, 2, 3, 4, and 5, respectively.

CONCLUSIONS

Self assessed pubertal development was positively associated with hormonal biomarkers of puberty.

In vitro biological-to-immunological ratio of serum gonadotropins throughout male puberty in children with insulin-dependent diabetes mellitus

Information on the impact of prolonged deficient glycemic control in the quality of the gonadotropin signal delivered by the pituitary gland during puberty in children with insulin-dependent diabetes mellitus (IDDM) is scarce. In the present study, we examined the impact of deficient glycemic control on bioactive LH and FSH concentrations and their corresponding biological-to-immunological (B:I) ratio in boys with poorly controlled, but systemically uncomplicated IDDM. Dual control groups comprising patients with well-controlled IDDM and healthy boys of comparable age and body mass index were included for appropriate comparisons within and between each pubertal stage. Patients with poorly controlled and well-controlled IDDM exhibited serum bioactive FSH levels and B:I FSH ratio similar to those showed by the healthy control group. In contrast, in early and mid-pubertal boys with poorly controlled IDDM bioactive LH levels were normal, but its B:I LH relationship was significantly (P < 0.05) decreased. This attenuation in the quality of the LH signal did not affect total serum T concentrations, and apparently, progression of puberty. Long-standing uncontrolled diabetes and the consequent metabolic disturbances and/or complications may aggravate the reproductive axis dysfunction and eventually provoke pubertal arrest.

Maturity assessment and curve progression in girls with idiopathic scoliosis

BACKGROUND

Scoliosis progression during adolescence is closely related to patient maturity. Maturity has various indicators, including chronological age, height and weight changes, and skeletal and sexual maturation. It is not certain which of these indicators correlates most strongly with scoliosis progression. The purpose of the present study was to evaluate various maturity measurements and how they relate to scoliosis progression.

METHODS

Physically immature girls with idiopathic scoliosis were evaluated every six months through their growth spurt with serial spinal radiographs; hand skeletal ages; Oxford pelvic scores; Risser sign determinations; height; weight; sexual staging; and serologic studies of the levels of selected growth factors, estradiol, bone-specific alkaline phosphatase, and osteocalcin. These measurements were then correlated with the curve-acceleration phase.

RESULTS

The period and pattern of curve acceleration began during Risser stage 0 for all patients. Skeletal maturation scores derived with the use of the Tanner-Whitehouse-III RUS method, particularly those for the metacarpals and phalanges, were superior to all other indicators of maturity. Regression of the scores provided good estimates of maturity relative to the period of curve progression (Pearson r = 0.93). The initiation of this period occurred simultaneously with digital changes from Tanner-Whitehouse-III stage F to G. At this stage, curves also separated into rapid, moderate, and low-acceleration patterns, with specific curve types in the rapid and moderate-acceleration groups. The low-acceleration group was not confined to a specific curve type.

CONCLUSIONS

The curve-acceleration phase separates curves into various types of curve progression. The Tanner-Whitehouse-III RUS scores are highly correlated with timing relative to the curve-acceleration phase and provide better maturity determination and prognosis determination during adolescence than the other parameters tested. Accurate skeletal maturity determination should be used as the primary maturity measurement in girls with idiopathic scoliosis.

Correlates of the peak height velocity in girls with idiopathic scoliosis

STUDY DESIGN

Prospective longitudinal.

OBJECTIVE

Determine correlates of the peak height velocity (PHV) in girls with idiopathic scoliosis.

SUMMARY OF BACKGROUND DATA

Only identifiable retrospectively, the PHV is the most useful known maturity marker in idiopathic scoliosis. Clinically useful correlates are needed to make PHV timing helpful.

METHODS

A total of 24 immature girls with idiopathic scoliosis were followed with serial heights, sexual staging, skeletal ages, spinal radiographs, insulin-like growth factor (IGF)-1, IGF binding protein-3, dehydroepiandrosterone sulfate, estradiol, bone-specific alkaline phosphatase, and osteocalcin levels. These markers were correlated to PHV timing.

RESULTS

There were 14 girls who had identifiable growth peaks that averaged 10.5 +/- 1.8 cm/y at age 11.7 +/- 1 years. At the PHV, all girls were Risser 0 with open triradiate cartilages. On a skeletal age radiograph, digital uncapped phalangeal epiphyses were indicative of pre-PHV and fused epiphyses of post-PHV. Capped but unfused epiphyses were indeterminate. Tanner stage 1 for breast strongly indicates pre-PHV. Stage 3 for breast and pubic hair occurred at or after the PHV, and stage 4 always occurred after PHV. Higher IGF-1 and estradiol levels after PHV are potentially discriminatory.

CONCLUSIONS

The PHV occurs during Risser 0 with open triradiate cartilages. If triradiate cartilages are open, then Tanner stages, IGF-1, estradiol levels, and the appearance of the epiphyses on a skeletal age radiograph are useful in determining status before or after PHV.

Normal onset of puberty have definitions of onset changed?

Puberty is the sequence of events that culminates in the ability to procreate. It is widely accepted that the onset of puberty in girls occurs on average at 8 years of age and that onset prior to 8 years of age is precocious puberty. As a result of the cross-sectional study by the American Association of Pediatrics, a movement exists to change the age limit of the onset of puberty to 6 years of age in black girls and 7 years of age in white girls. We should be cautious in adhering to strict age limits when diagnosing precocious puberty. Also the rapidity and progression of puberty should be evaluated, and if appropriate, therapy to suppress pubertal development considered.

Neuroendocrine facets of human puberty

The unfolding of pubertal growth and maturation entails multisystem collaboration. Most notably, the outflow of gonadotropins and growth hormone (GH) proceeds both independently and jointly. The current update highlights this unique dependency in the human.

Sensitive immunoassay and in vitro bioassay demonstrate constant bioactive/immunoreactive ratio of luteinizing hormone in healthy boys during the pubertal maturation

The quality of serum LH was assessed during pubertal maturation in boys by measuring immunoreactive (I) LH by a time-resolved immunofluorometric assay (IFMA, Delfia), and bioactive (B) LH by a sensitized in vitro bioassay. Seven samples were collected at 3-mo intervals from 14 healthy boys (median starting age 11.8 y) during pubertal maturation from Tanner stage I-III or II-IV (n = 7 for each). The mouse Leydig cell in vitro bioassay was sensitized 10-fold, to 0.05-0.1 IU/L, by including 1.5 mumol/L of forskolin in the incubation medium. The I- and B-LH levels showed good linear correlation throughout the concentration range analyzed. Mean I-LH increased between the pubertal stages I-IV from 0.42 to 2.24 IU/L and that of B-LH from 1.35 to 5.04 IU/L. No concomitant change occurred in the B-LH/I-LH (B/I) ratio, which was 2.84 +/- 0.54 in stage I and 2.58 +/- 0.48 in stage IV (mean +/- SEM, n = 7). Although the B/I ratios of LH varied from 0.59 to 5.85 in the samples analyzed, the intraindividual variation was small (mean coefficient of variance, 22%). In conclusion, IFMA and sensitized in vitro bioassay showed in healthy boys a similar 4-5-fold increase in the mean LH concentration during pubertal maturation, with no concomitant change in the B/I ratio. The sensitized in vitro bioassay of LH is useful for analysis of the low peripubertal LH levels. The good correlation between the I-LH and B-LH levels, and the lack of change in LH B/I ratio, indicate that IFMA correctly estimates the LH levels upon evaluation of pubertal maturation.

A new endocrinological and immunological syndrome in SLE: elevation of human chorionic gonadotropin and of antibodies directed against ovary and endometrium antigens

We have analysed the levels of gonadotropins in male and female patients with systemic lupus erythematosus (SLE). Human chorionic gonadotropin hCG was elevated in 23.8% of patients compared with 12.7% of controls. hCG isolated from the serum of SLE patients was bioactive in vitro. Levels of hCG were significantly correlated with those of its beta-subunit but not with the levels of follicle stimulating hormone, luteinizing hormone, prolactin alphafetoprotein or carcino embryonic antigen. A high percentage of patients presented an organ-specific humoral immune response against ovarian (26.7%) and endometrial (40%) antigens compared with controls (8% and 7.6%, respectively). Endometrial antibodies were significantly correlated to the levels of prolactin. The ovarian tumour marker CA-125 was elevated in 32.5% of patients, including two males. As a whole, these elements delineate a new endocrine and immunological syndrome in SLE in which the elevation of hCG could provide a central physiological explanation for a series of endocrine alterations that characterize this disease.