Body mass index in girls with idiopathic central precocious puberty during and after treatment with GnRH analogues.

BACKGROUND: In girls with Idiopathic Central Precocious Puberty (ICPP) concern has been raised by the potential impact of GnRH-analogues (GnRHa) treatment on body weight. We evaluated the effect of GnRHa on Body Mass Index (BMI) in girls with ICPP according to weight status at diagnosis. METHODS: One hundred seventeen ICPP girls were divided according to pretreatment weight status in: normal weight (NW), overweight (OW) and obese (OB). BMI at one and two years of treatment was assessed. BMI-SDS of 60 patients who reached adult height (AH) was compared to that of 33 ICPP untreated girls. RESULTS: NW girls significantly increased their baseline BMI-SDS at 1 and 2 years of treatment. OW girls only had a significant increment at one year of treatment while OB girls showed no BMI-SDS change. Patients evaluated at AH (at least four years after GnRHa withdrawal) showed a significant decrease on BMI compared to baseline and a significantly lower BMI than the untreated group. CONCLUSION: In ICPP girls the BMI increase under GnRHa was inversely related to the pretreatment weight status. In the long term follow-up, no detrimental effect of GnRHa on body weight was observed. BMI-SDS was lower in treated than in untreated girls.

Mutations of the KISS1 gene in disorders of puberty.

CONTEXT: Kisspeptin, encoded by the KISS1 gene, is a key stimulatory factor of GnRH secretion and puberty onset. Inactivating mutations of its receptor (KISS1R) cause isolated hypogonadotropic hypogonadism (IHH). A unique KISS1R-activating mutation was described in central precocious puberty (CPP). OBJECTIVE: Our objective was to investigate KISS1 mutations in patients with idiopathic CPP and normosmic IHH. PATIENTS: Eighty-three children with CPP (77 girls) and 61 patients with IHH (40 men) were studied. The control group consisted of 200 individuals with normal pubertal development. METHODS: The promoter region and the three exons of KISS1 were amplified and sequenced. Cells expressing KISS1R were stimulated with synthetic human wild-type or mutant kisspeptin-54 (kp54), and inositol phosphate accumulation was measured. In a second set of experiments, kp54 was preincubated in human serum before stimulation of the cells. RESULTS: Two novel KISS1 missense mutations, p.P74S and p.H90D, were identified in three unrelated children with idiopathic CPP. Both mutations were absent in 400 control alleles. The p.P74S mutation was identified in the heterozygous state in a boy who developed CPP at 1 yr of age. The p.H90D mutation was identified in the homozygous state in two unrelated girls with CPP. In vitro studies revealed that the capacity of the P74S and H90D mutants to stimulate IP production was similar to the wild type. After preincubation of wild-type and mutant kp54 in human serum, the capacity to stimulate signal transduction was significantly greater for P74S compared with the wild type, suggesting that the p.P74S variant is more stable. Only polymorphisms were found in the IHH group. CONCLUSION: Two KISS1 mutations were identified in unrelated patients with idiopathic CPP. The p.P74S variant was associated with higher kisspeptin resistance to degradation in comparison with the wild type, suggesting a role for this mutation in the precocious puberty phenotype.

Características clínicas, endocrinas y metabólicas de una población argentina de niñas con pubarca prematura / Clinical, hormonal and metabolic findings in argentinean girls with premature pubarche

La pubarca prematura se ha asociado con alteraciones hormonales y metabólicas. Se estudiaron 40 niñas con pubarca prematura de 7,23 ± 0,29 años (media ± ESM). Se evaluó grado de desarrollo, talla, edad ósea, IMC y peso al nacimiento (PN). Se dosaron andrógenos, gonadotrofinas, lípidos, glucemia e insulina, HOMA e índice glucemia/insulina (G/I) y se compararon con un grupo control normal de 25 niñas. Las pacientes se dividieron según el nivel de sulfato de dehidroepiandrosterona (SDHEA) en dos grupos, Pre A (Pre adrenarca), < 400 ng/ml, n= 17 y Post A (Post adrenarca) < 400 ng/ml , n= 23. El grupo Post A tuvo mayor edad cronológica, edad ósea y grado de vello pubiano que el Pre A, sin diferencias en IMC ni en peso de nacimiento (PN). Insulina y HOMA fueron mayores y G/I menor en Post A que en Pre A y grupo control. Dos niñas en Post A tuvieron franca resistencia a la insulina. 64 % de las niñas en Pre A y 59 % en Post A tuvieron valores elevados o limítrofes de colesterol total (CT). Conclusiones: el grupo Post A presentó menor sensibilidad insulínica y ambos grupos de pacientes tuvieron valores de CT elevados, alteraciones que podrían favorecer el riesgo de futuras complicaciones. Se recomienda el seguimiento a largo plazo de todas las niñas con pubarca prematura.

Precocious pubarche in girls is caused by premature adrenarche in most cases. Less frequently it occurs in absence of biochemical markers of adrenarche being ascribed to increased target tissue sensitivity. Premature pubarche with pronounced adrenarche has been associated with insulin resistance and dyslipemia, especially in girls with history of low birth weight. Most studies have been conducted in hispanic and affrican-american patients. We studied a total of 40 argentinean girls with isolated premature pubarche, aged 7.23 ± 0.29 years (mean ± SEM) at the moment of diagnosis. Grade of sexual development, height, weight, BMI and birth weight (BW) were recorded. Dehidroepiandrosterone sulphate (DHEAS), androstenedione (A), testosterone (T), 17OH progesterone (17 OHP), SHBG, LH, FSH, PRL and estradiol were measured. Total cholesterol (TC), LDL cholesterol (LDL- C), triglycerides (TGC), glucose, insulin, HOMA and fasting glucose/ insulin index (G/I) were evaluated and compared with those in a control group of 25 normal girls. Patients were divided into two groups: Pre A (Pre adrenarche), with DHEAS < 400 ng/ml, and Post A (Post adrenarche), with DHEAS > 400 ng/ml. Post A girls had higher chronological age, bone age advancement and grade of pubic hair development than Pre A girls. No difference was found regarding BMI or BW. Besides higher DHEAS levels, Post A girls showed elevated A and 17OHP levels than Pre A girls (86 ± 8 vs 35 ± 4 ng/dl, p<0. 0001 and 1.1 ± 0.09 vs 0.75 ± 0.07 ng/ml, p< 0.01, respectively). Insulin levels (µUI/ml) were 4.51 ± 0.75 in Pre A, 6.53 ± 1.11 in Post A and 4.05 ± 0.45 in control group. Fasting G/I was 24.07 ± 3.75 in Pre A , 18.4 ± 2.34 in Post A and 25.41 ± 2.31 in controls. HOMA was 0.90 ± 0.12 in Pre A, 1.35 ± 0.22 in Post A and 0.89 ± 0.11 in control group. Post A girls had higher insulin and HOMA and lower G/I than control group girls (p<0.05) while those parameters in Pre A girls were not different than in normal control subjects. Only two patients in Post A group had HOMA and G/I consistent with insulin resistance. TC was higher in Pre A than in control group (182.2 ± 4.9 vs156.7 ± 8.5 mg/dl, p<0.05). According to The National Cholesterol Education Program definition, 64 % of Pre A girls and 59 % of Post A girls had elevated or borderline TC levels. TGC values were not different among Pre A, Post A and control group (81.1 ±7.1, 77.6 ± 6.1 and 71.9 ± 4.7 mg/dl, respectively. Summary and Conclusions: In this cohort of argentinean girls with premature pubarche, we did not find a significant history of intrauterine growth retardation. Patients with biochemical pattern of adrenarche showed clinical signs of androgen exposure (accelerated bone age, more advanced degree of pubic hair development) and a serum profile suggestive of reduced insulin sensitivity compared with those without biochemical adrenarche. Both groups of patients had undesirable total cholesterol levels. These findings support the recommendation of long-term follow-up for all girls with premature pubarche.

[Molecular analysis of the most frequent mutations associated with congenital adrenal hyperplasia secondary to 21-hydroxylase enzyme deficiency]. / Análisis molecular de las mutaciones más frecuentes asociadas a la hiperplasia suprarrenal congénita por déficit de la enzima 21 hidroxilasa.

Most cases (90%) of congenital adrenal hyperplasia (CAH) are secondary to steroid 21-hydroxylase enzyme deficiency (P450c21). In human, the P450c21 gene (CYP21B) is present along with a non functional pseudogene (CYP21A). These genes, located in chromosome 6, present a sequence homology of 98%. This high homology and the complexity of this gene locus brings about considerable difficulties in its molecular analysis and in the interpretation of the results. The aim of the present study was to elaborate an adequate strategy for the analysis of the most frequent mutations described in the CYP21B gene. A total of 77 patients with clinical and biochemical diagnosis of CAH secondary to P450c21 enzyme deficiency, as well as 170 unaffected relatives, were studied. They belonged to 73 unrelated families (146 chromosomes). The strategy allowed for the differentiation of patients with homozygous point mutations (PM), with PM in one allele and deletions, conversions, Ex3 or Cluster Ex6 PM in the other, even though parents were not always available for the study. Furthermore, it allowed for the discrimination of heterozygous deletions or conversions of the CYP21B gene from duplications of the non functional gene CYP21A, as well as CYP21B and A deletions from normal copies of the two genes. An exhaustive molecular analysis of this gene is necessary for an adequate characterization of the alterations present in this locus.

Análisis molecular de las mutaciones más frecuentes asociadas a la hiperplasia suprarrenal congénita por déficit de la enzima 21 hidroxilasa. / [Molecular analysis of the most frequent mutations associated with congenital adrenal hyperplasia secondary to 21-hydroxylase enzyme deficiency]

Most cases (90

) of congenital adrenal hyperplasia (CAH) are secondary to steroid 21-hydroxylase enzyme deficiency (P450c21). In human, the P450c21 gene (CYP21B) is present along with a non functional pseudogene (CYP21A). These genes, located in chromosome 6, present a sequence homology of 98

. This high homology and the complexity of this gene locus brings about considerable difficulties in its molecular analysis and in the interpretation of the results. The aim of the present study was to elaborate an adequate strategy for the analysis of the most frequent mutations described in the CYP21B gene. A total of 77 patients with clinical and biochemical diagnosis of CAH secondary to P450c21 enzyme deficiency, as well as 170 unaffected relatives, were studied. They belonged to 73 unrelated families (146 chromosomes). The strategy allowed for the differentiation of patients with homozygous point mutations (PM), with PM in one allele and deletions, conversions, Ex3 or Cluster Ex6 PM in the other, even though parents were not always available for the study. Furthermore, it allowed for the discrimination of heterozygous deletions or conversions of the CYP21B gene from duplications of the non functional gene CYP21A, as well as CYP21B and A deletions from normal copies of the two genes. An exhaustive molecular analysis of this gene is necessary for an adequate characterization of the alterations present in this locus.

Clinical assessment and serum hormonal profile in prepubertal hypertrichosis.

Twenty-two prepubertal girls with hypertrichosis were studied and compared to 10 prepubertal normal girls. Hypertrichosis was assessed according to a score that considers the amount and the distribution of vellus hair in androgen- and non-androgen-sensitive areas. Serum androgen profile and free androgen index (FAI) were determined in both groups. The hypertrichosis score was higher in patients than in the normal girls. Testosterone levels and FAI were increased in patients when compared to control; 3alpha-androstanediol glucuronide levels above 2 SD from the control mean were found in 10 girls and all hormonal parameters falling in the normal range were found in 4 girls. The new score designed to assess the degree of hypertrichosis was useful to differentiate between normal and pathological hair growth. Although most of the girls with prepubertal hypertrichosis showed an increased androgen bio-availability, a slight increase in peripheral 5alpha-reductase activity and a completely normal androgen profile was also associated with a pathological hair growth.

Detección de la deficiencia de 21 hidroxilasa en su forma no clásica en una población argentina de 100 niñas con pubarquia precoz / Detection of non classical 21-O-Hase deficiency in an argentinean population of 100 girls with precocious pubarche

Antecedentes: el déficit no clásico de 21 hidroxilasa es una alteración de la esteroideogénesis adrenal que puede expresarse como pubarquia precoz en la infancia. Para analizar la prevalencia de ésta diferencia en una población argentina con pubarquia precoz, se estudiaron 100 niñas (edad cronológica: 6,55ñ1,62 años) con aparición de vello púbico antes de los 8 años de edad. Métodos: se evaluaron la talla, la edad ósea (EO) y el grado de desarrollo (Tanner). Se efectuó una prueba de estimulación adrenal con ACTH 0,25 mg i.v., determinando 17OH progesterona y cortisol basales y a los 60 min. Los resultados se compararon con el monograma de María New et al. Se midieron las concentraciones basales de sulfato de dehidroepiandrosterona (SDHEA), androstenediona (A), testosterona (T) y proteína ligadora de hormonas sexuales (SHBG). Resultados: clínicamente se distinguieron 2 grupos, 82 niñas con pubarquia precoz aislada (PPA) y 18 con pubarquia precoz asociada con hipertrofia de clítoris (PPH). Tres pacientes PPA y dos PPH presentaron concentraciones elevadas de 17OHP lo que permitió efectuar el diagnóstico de hiperplasia suprarrenal de comienzo tardío. El resto de las pacientes se diagnosticó como pubarquia precoz idiopática. Las concentraciones de T, A y SDHEA en las pacientes con pubarquia precoz idiopática estuvieron en los límites puberales normales, mientras que las concentraciones de SHBG se encontraron en el límite prepuberal. Conclusiones: en nuestra población estudiada se encontró un 5 por ciento de déficit no clásico de 21-hidroxilasa. Esto indicaría la necesidad de solicitar la prueba de estimulación con ACTH en niñas con pubarquia precoz para la detección de ésta deficiencia enzimática (AU)

Detección de la deficiencia de 21 hidroxilasa en su forma no clásica en una población argentina de 100 niñas con pubarquia precoz / Detection of non classical 21-O-Hase deficiency in an argentinean population of 100 girls with precocious pubarche

Antecedentes: el déficit no clásico de 21 hidroxilasa es una alteración de la esteroideogénesis adrenal que puede expresarse como pubarquia precoz en la infancia. Para analizar la prevalencia de ésta diferencia en una población argentina con pubarquia precoz, se estudiaron 100 niñas (edad cronológica: 6,55ñ1,62 años) con aparición de vello púbico antes de los 8 años de edad. Métodos: se evaluaron la talla, la edad ósea (EO) y el grado de desarrollo (Tanner). Se efectuó una prueba de estimulación adrenal con ACTH 0,25 mg i.v., determinando 17OH progesterona y cortisol basales y a los 60 min. Los resultados se compararon con el monograma de María New et al. Se midieron las concentraciones basales de sulfato de dehidroepiandrosterona (SDHEA), androstenediona (A), testosterona (T) y proteína ligadora de hormonas sexuales (SHBG). Resultados: clínicamente se distinguieron 2 grupos, 82 niñas con pubarquia precoz aislada (PPA) y 18 con pubarquia precoz asociada con hipertrofia de clítoris (PPH). Tres pacientes PPA y dos PPH presentaron concentraciones elevadas de 17OHP lo que permitió efectuar el diagnóstico de hiperplasia suprarrenal de comienzo tardío. El resto de las pacientes se diagnosticó como pubarquia precoz idiopática. Las concentraciones de T, A y SDHEA en las pacientes con pubarquia precoz idiopática estuvieron en los límites puberales normales, mientras que las concentraciones de SHBG se encontraron en el límite prepuberal. Conclusiones: en nuestra población estudiada se encontró un 5 por ciento de déficit no clásico de 21-hidroxilasa. Esto indicaría la necesidad de solicitar la prueba de estimulación con ACTH en niñas con pubarquia precoz para la detección de ésta deficiencia enzimática

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.

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.