| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Special Features |
Groupe hospitalier Cochin-Saint Vincent de Paul (C.B., J.-C.C., J.-L.C.), 75014 Paris, France; Centre hospitalier Charles Nicolle (C.L.), 76031 Rouen, France; Centre hospitalier Mère et Enfant (A.D.), 44000 Nantes, France; Hôpital Lapeyronie (C.S.), 34000 Montpellier, France; Centre hospitalier La Mère et lEnfant (A.-M.B.), 25030 Besançon, France; and Hôpital Debrousse (Y.M.), 69322 Lyon, France
Address all correspondence and requests for reprints to: Dr. Claire Bouvattier, Endocrinologie Pédiatrique, Groupe hospitalier Cochin-Saint Vincent de Paul, 82 av Denfert Rochereau, 75014 Paris, France. E-mail: c.bouvattier{at}svp.ap-hop-paris.fr
| Abstract |
|---|
|
|
|---|
| Introduction |
|---|
|
|
|---|
-REDUCED metabolite dihydrotestosterone are essential to virilize the urogenital tract of male embryos and act through the AR in target cells. Androgen insensitivity syndrome (AIS) is the most common cause of ambiguous genitalia (1, 2). Complete AIS (CAIS) is associated with female appearance of external genitalia, blind vagina, and presence of the testes in the inguinal areas. Partial androgen insensitivity [partial AIS (PAIS)] encompasses a spectrum of virilization defects ranging from minimal virilization in an XY individual (clitoromegaly) to perineoscrotal hypospadias. Molecular cloning and expression of the AR gene has allowed the identification of genetic lesions in the AR in most cases, although the phenotypic expression of a given mutation is quite variable (3). In 1973, Forest et al. (4) described the evolution of plasma T concentration during the first months of life in full-term males, with a progressive rise from the first postnatal week to the second month and a gradual decrease to prepubertal levels around the age of 6 months. In parrallel, plasma LH concentrations rose until the third month of life before declining to prepubertal values slightly later than T (4, 5). This physiological T peak is commonly used by pediatric endocrinologists as a way to evaluate the male gonadotropic axis during the first 46 months of life.
Postpubertal patients with CAIS and intact testes have increased plasma concentrations of LH and FSH and normal or high T levels (6, 7). Studies in infants and neonates with AIS are restricted to a few case reports (8, 9, 10, 11). In the present study, we observed the hormonal profile in 15 patients with AIS during the first 3 months of life.
| Subjects and Methods |
|---|
|
|
|---|
Fifteen 46,XY newborns with androgen insensitivity were longitudinally followed during the first 90 d of life. Ten exhibited the classical features of CAIS, with female phenotypic appearance and gender assignment. Five had PAIS and were raised as males. All had a mutation of the AR gene (Table 1
). There was a familial history in 7/15 cases. Patients 12 and 13 are brothers and were previously described (3).
|
T was measured by a direct RIA (Orion, Turku, Finland) with a detection limit of 0.17 nM and intra- and interassay coefficients of variation of 8% and 8.5%, respectively, at the level 2 nM and less than 8% at higher levels. Measurements were performed on d 27, 30, 60, and 90. In addition, on d 90, plasma T was measured after human CG (hCG) stimulation (3 im injections of 1500 U every other day). LH and FSH were measured 0, 15, 30, 45, 60, 90, and 120 min after iv injection of GnRH (100 µg/m2) on d 60 (12) by time-resolved immunofluorometric assay (Delfia; Wallac, Inc., Turku, Finland). Normal sex- and age-specific values for the plasma concentrations of T, LH, and FSH were used for comparison (13, 14, 15, 16, 17).
Direct sequencing of the AR gene was performed after PCR using an 373A sequencer and Taq dye terminator kit (PE Applied Biosystems, Foster City, CA).
Statistical analysis
Data are reported as mean ± 1 SD. For comparisons, parametric methods were used: t test (2-way test) and Pearson correlation test, to examine relationships between variables. For all statistical tests, significance was defined as P < 0.05.
| Results |
|---|
|
|
|---|
Hormonal values are presented in Figs. 1
, 2
, and 3
and Tables 1
and 2
. In CAIS, basal plasma T values were below the normal range from d 27 to d 90 in 9 of 10 patients. Only 1 patient with CAIS (patient no. 2) had T values within the normal range for males at d 30 and d 60 (5.5 and 9.3 nM, respectively). In infants with PAIS, T was significantly higher than in those with CAIS at d 30 (P = 0.005) and d 60 (P = 0.004), with median values between 4.8 and 18 nM during the 3 first months of life. The highest T value was measured at d 30 in all 5 cases.
|
|
|
|
= 44.7 nM; range, 12.193.6) and PAIS (
= 29.8 nM; range, 14.539.8). Compared with baseline values, the median T rise, after hCG stimulation, was 20-fold in CAIS but only 2-fold in PAIS.
In 9 of 10 patients with CAIS, the median basal plasma LH levels, during the 3 first months of life, were lower than 0.9 U/liter. In contrast, patients with PAIS had significantly higher median values of 8.7 U/liter (P = 0.004) at d 30 and 2.8 U/liter (P = 0.02) at d 60. Peak plasma LH, after stimulation with GnRH, was also different between the 2 groups: the median value was 19.9 U/liter in PAIS (range, 15.524 U/liter) and 5.2 U/liter in CAIS (P = 0.0004, Tables 1
and 2
, Fig. 3
). Basal FSH levels were similar in the 2 groups. Peak plasma FSH, after stimulation with GnRH, was higher in PAIS than in CAIS (10.9 vs. 2 U/liter, P = 0.04).
| Discussion |
|---|
|
|
|---|
The hypothalamo-pituitary-gonadal axis is transiently activated during the first months of human postnatal life. After birth, high levels of maternal E2 drop rapidly, and plasma T falls, due to the clearance of hCG. These events contribute to the rise of circulating gonadotropins, responsible for the subsequent rise of T. In primates, the postnatal T surge can be abolished by a GnRH agonist, confirming its gonadotropin dependency (4, 13, 16, 18).
Published studies of hormonal investigations in patients with AIS have concentrated on older children and adults (6, 7, 10, 11, 19, 20). Postpubertal patients with complete forms of androgen resistance (CAIS) have markedly elevated serum LH levels and normal-to-high T concentrations, suggesting that the hypothalamic-pituitary unit is relatively unresponsive to the inhibitory feedback effects of circulating T. FSH levels are more variable, indicating normal control by other gonadal products, such as inhibin. Postpubertal patients with PAIS also have elevated LH values.
Studies in neonates with AIS are restricted to a few case reports (1, 9, 18, 21, 22, 23). Our five PAIS patients follow the expected pattern of exaggerated T and LH surge, similar to the findings in pubertal patients. Their plasma T and LH values were often above the range of normal controls. This increase of LH secretion reflects the postnatal sensitivity of the gonadotropic axis to negative feedback by androgens, altered by the AR mutation. Surprisingly, all but one CAIS newborn had no activation of the gonadotropic axis, with no LH and T surge, and a significantly decreased response of LH to GnRH at 3 months of life. This remarkable difference between CAIS and PAIS suggests that the normal transient LH rise in male infants requires prior, intrauterine, androgen action on the gonadotropic axis. In addition, our results rule out a major role for postnatal E2 decrease as a primary mechanism driving the neonatal LH surge, as previously suggested (24). We have no explanation for the different pattern observed in one of our patients with CAIS, who had a normal, or even strong, increase of T and LH. T biosynthesis assessed by Leydig cell response to hCG was normal or high in all cases. Plasma T increased more than five times in all neonates with CAIS, whereas a 2- to 3-fold increase is generally considered normal (25).
In conclusion, our study provides data about the regulation of the gonadotropic axis during the first months of life in individuals with androgen insensitivity. The postnatal rise of T and LH is normal or elevated in PAIS but absent in almost all infants with CAIS. We conclude that the postnatal T rise requires the receptivity of the hypothalamo-pituitary axis to T, as described in male rats (26).
| Acknowledgments |
|---|
| Footnotes |
|---|
Received June 30, 2000.
Accepted July 2, 2001.
| References |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
M. M. Centenera, J. M. Harris, W. D. Tilley, and L. M. Butler Minireview: The Contribution of Different Androgen Receptor Domains to Receptor Dimerization and Signaling Mol. Endocrinol., November 1, 2008; 22(11): 2373 - 2382. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Bodo and E. F. Rissman The Androgen Receptor Is Selectively Involved in Organization of Sexually Dimorphic Social Behaviors in Mice Endocrinology, August 1, 2008; 149(8): 4142 - 4150. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Aksglaede, J. H Petersen, K. M Main, N. E Skakkebaek, and A. Juul High normal testosterone levels in infants with non-mosaic Klinefelter's syndrome Eur. J. Endocrinol., September 1, 2007; 157(3): 345 - 350. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Coutant, D. Mallet, N. Lahlou, N. Bouhours-Nouet, A. Guichet, L. Coupris, A. Croue, and Y. Morel Heterozygous Mutation of Steroidogenic Factor-1 in 46,XY Subjects May Mimic Partial Androgen Insensitivity Syndrome J. Clin. Endocrinol. Metab., August 1, 2007; 92(8): 2868 - 2873. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Bergada, C. Milani, P. Bedecarras, L. Andreone, M. G. Ropelato, S. Gottlieb, C. Bergada, S. Campo, and R. A. Rey Time Course of the Serum Gonadotropin Surge, Inhibins, and Anti-Mullerian Hormone in Normal Newborn Males during the First Month of Life J. Clin. Endocrinol. Metab., October 1, 2006; 91(10): 4092 - 4098. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Bouvattier, B. Mignot, H. Lefevre, Y. Morel, and P. Bougneres Impaired Sexual Activity in Male Adults with Partial Androgen Insensitivity J. Clin. Endocrinol. Metab., September 1, 2006; 91(9): 3310 - 3315. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Veldhuis, J. N. Roemmich, E. J. Richmond, and C. Y. Bowers Somatotropic and Gonadotropic Axes Linkages in Infancy, Childhood, and the Puberty-Adult Transition Endocr. Rev., April 1, 2006; 27(2): 101 - 140. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Pinto, V. Abadie, R. Mesnage, J. Blustajn, S. Cabrol, J. Amiel, L. Hertz-Pannier, A. M. Bertrand, S. Lyonnet, R. Rappaport, et al. CHARGE Syndrome Includes Hypogonadotropic Hypogonadism and Abnormal Olfactory Bulb Development J. Clin. Endocrinol. Metab., October 1, 2005; 90(10): 5621 - 5626. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. M. Grumbach A Window of Opportunity: The Diagnosis of Gonadotropin Deficiency in the Male Infant J. Clin. Endocrinol. Metab., May 1, 2005; 90(5): 3122 - 3127. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Raivio, J. Toppari, M. Kaleva, H. Virtanen, A.-M. Haavisto, L. Dunkel, and O. A. Janne Serum Androgen Bioactivity in Cryptorchid and Noncryptorchid Boys during the Postnatal Reproductive Hormone Surge J. Clin. Endocrinol. Metab., June 1, 2003; 88(6): 2597 - 2599. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Pitteloud, F. J. Hayes, A. Dwyer, P. A. Boepple, H. Lee, and W. F. Crowley Jr. Predictors of Outcome of Long-Term GnRH Therapy in Men with Idiopathic Hypogonadotropic Hypogonadism J. Clin. Endocrinol. Metab., September 1, 2002; 87(9): 4128 - 4136. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. A. Quigley The Postnatal Gonadotropin and Sex Steroid Surge--Insights from the Androgen Insensitivity Syndrome J. Clin. Endocrinol. Metab., January 1, 2002; 87(1): 24 - 28. [Abstract] [Full Text] [PDF] |
||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |