How to evaluate gonadal function in the cryptorchid boy. Lessons from new testicular markers

Correlation of anti-Mullerian hormone with humanchorionic gonadotropin test in the evaluation of testicular function of children with 46 XY male hypogonadism: Use of anti-Mullerian hormone as abiomarker

AIM

It is challenging to evaluate reproductive potential during childhood. These challenges necessitate the use of invasive dynamic tests. Although the anti-Mullerian hormone (AMH) is a reliable biomarker in evaluating testicular function, especially in the pre-pubertal period, there are uncertainties concerning its use in a clinical setting. This study is focused on comparing the AMH and human chorionic gonadotropin (hCG) test in boys with hypogonadism.

METHODS

A total of 160 boys aged between 0 and 18 years who presented with complaints associated with hypogonadism were prospectively enrolled in the study. All children were assigned to the following five groups: gonadal disorders (n = 34), androgen synthesis and end organ effect disorder (n = 48), isolated genital malformation disorders (n = 57), hypogonadotropic hypogonadism (n = 15) and constitutional delayed puberty (n = 6). All children underwent a short 3-day hCG test (1500 U/m² /day). The concordance and correlation were evaluated between the hCG test and AMH.

RESULTS

All groups exhibited a strong correlation (r₁₆₀ = 0.689) and strong concordance (Kappa coefficient₁₆₀ = 0.7) between the AMH and hCG test. Values of AMH higher than 32.7 pmol/L and hCG responses higher than 86 pmol/L were significant as indicative markers of functional testicular tissue presence.

CONCLUSIONS

This study has shown that there is a strong correlation between the AMH and short-term hCG test and that values of AMH higher than 32.7 pmol/L and stimulated testosterone higher than 86 pmol/L can be used as indicators of functionally sufficient testicular tissue. These results indicate that AMH value can be used as a reliable and useful biomarker in the evaluation of the testicular function in 46 XY hypogonadism.

Changes in peripheral anti-Müllerian hormone concentration and their relationship with testicular structure in beef bull calves

The aim of this study was to clarify the time-course of changes in anti-Müllerian hormone (AMH) and testosterone (T) concentrations in peripheral blood and to determine the relationships between blood AMH concentration and testicular development during the early postnatal and prepubertal periods in beef bull calves. A total of 17 Japanese Black bull calves were enrolled in this study. The wk in which the calf was born (within 6 d after birth) was defined as M 0. Blood samples were taken once in every mo from M 0 to M 6 from each bull calf, and plasma AMH and T concentrations were determined. Of the 17 calves, 10 were castrated at 6 mo of age (prepuberty) and the right testis was histologically examined. Plasma AMH concentration (means ± SE) at M 0, 1, and 2 were 123.5 ± 9.8, 189.6 ± 18.7, and 254.6 ± 14.1 ng/mL, respectively. From M 0 through M 2, plasma AMH concentration was significantly greater each mo than in the previous mo (P < 0.05); however, plasma AMH concentration significantly decreased over the last 3 mo of the study (P < 0.05). The average age at which plasma AMH concentration was the highest was 2.3 ± 0.1 mo of age. Plasma T concentration significantly increased from M 0 (0.18 ± 0.02 ng/mL) until M 6 (6.52 ± 1.41 ng/mL). Plasma AMH and T concentrations at M 4, 5, and 6 were significantly negatively correlated (P < 0.05). Linear regression did not reveal a significant relationship between Sertoli or Leydig cell numbers and plasma AMH or T concentrations, respectively. In conclusion, blood AMH concentration peaks at 2 mo of age and is negatively correlated with blood T concentration from 4 to 6 mo of age. Although prepubertal blood AMH or T concentrations did not reflect Sertoli or Leydig cell numbers at the end of the prepubertal period, blood AMH concentration may be indicative of abnormal Sertoli cells function.

The role of anti-Mullerian and inhibin B hormones in the evaluation of 46,XY disorders of sex development

OBJECTIVE

To assess the sensitivity and specificity of anti-Mullerian hormone (AMH) and inhibin B for diagnosis of 46,XY disorders of sex development (DSD).

PATIENTS AND METHODS

The study included 43 patients of 46,XY DSD and compared them with 43 healthy, male, age matched controls. All patients underwent karyotyping, assessment of testosterone, dihydrotestosterone (DHT) and Δ4-androstendione (Δ4A) basal and after human chorionic gonadotropin (HCG) testing. Basal dehydroepiandrosterone (DHEA) was measured. Ultrasonograghy was also done and some cases underwent laparoscopy or gonadal biopsies. Basal AMH and inhibin B were measured in both cases and controls.

RESULTS

The mean age of patients was 5.16±4.24 years. There were significant correlations between basal AMH and HCG stimulated testosterone and DHT (r=0.64; p<0.001 and r=0.52; p<0.001, respectively). Also, significant positive correlations were found between inhibin B and HCG as well as stimulated testosterone and DHT (r=0.62; p<0.001 and r=0.44; p=0.003, respectively). A highly significant correlation was found between AMH and inhibin B (r=0.78; p<0.001). The sensitivity of AMH was (96.6%), specificity (60.7%), NPV (89.5%) and PPV (83.6%). Best cut-off value was (27.11 IU/mL) while overall accuracy was (85%). The sensitivity of inhibin B was (96.6%), specificity (67.9%), NPV (90.5%), PPV (86.2%), and best cut-off value was (41.9 IU/mL) with an overall accuracy (87%).

CONCLUSION

AMH and inhibin B are valuable, and reliable noninvasive parameters for the detection of functioning testicular tissues in prepubertal patients.

Application of the new classification on patients with a disorder of sex development in indonesia

Disorder of sex development (DSD) patients in Indonesia most often do not receive a proper diagnostic evaluation and treatment. This study intended to categorize 88 Indonesian patients in accordance with the new consensus DSD algorithm. Diagnostic evaluation including clinical, hormonal, genetic, imaging, surgical, and histological parameters was performed. Fifty-three patients were raised as males, and 34 as females. Of 22 patients with 46, XX DSD, 15 had congenital adrenal hyperplasia, while in one patient, an ovarian Leydig cell tumor was found. In all 58 46, XY DSD patients, 29 were suspected of a disorder of androgen action (12 with an androgen receptor mutation), and in 9, gonadal dysgenesis was found and, in 20, severe hypospadias e.c.i. Implementation of the current consensus statement in a resource-poor environment is very difficult. The aim of the diagnostic workup in developing countries should be to end up with an evidence-based diagnosis. This is essential to improve treatment and thereby to improve the patients' quality of life.

A visual pitfall: persistent Müllerian duct syndrome (PMDS)

Persistent Müllerian Duct Syndrome (PMDS) is a rare disorder of the anti-mullerian hormone (AMH) synthesis or receptor, which due to the visual contrast of normal masculine external genitalia and female internal genitalia can raise confusion, sometimes during surgery for cryptorchidism or hernia inguinalis. For an acute and accurate analysis of such a situation a thorough knowledge of gonadal embryology is mandatory. The diagnosis is made on finding Müllerian structures in an individual with complete virilization without signs of hypocortisolism or exposition to maternal androgens during foetal life. Karyotyping and gonadal biopsy provide additional information to confirm the diagnosis. As the risk of malignant transformation is not clear, orchidopexy is advised in patients with cryptorchidism, with lifelong palpatory follow-up. In case of urologic symptoms, surgical removal of the Müllerian remnants can be considered, with careful attention for the vulnerable ductus deferens. Despite optimal treatment the prognosis regarding fertility remain uncertain.

Unexpected mosaicism of R201H-GNAS1 mutant-bearing cells in the testes underlie macro-orchidism without sexual precocity in McCune-Albright syndrome

McCune-Albright syndrome (MAS), usually presenting with polyostotic bone dysplasia, café-au-lait skin lesions and sexual precocity, results from a somatic activating mutation of the GNAS1 gene, which encodes the Gs-alpha protein involved in signalling of several G-protein-coupled receptors. The clinical spectrum depends on tissue distribution of mutant-bearing cells. Sexual precocity has been ascribed to the occurrence of a mutant GNAS1 allele in the gonadal anlage, from which all somatic cells of the differentiated gonads arise. In boys, precocious activation of Leydig cell androgen secretion results in pubertal spermatogenesis, leading to testicular enlargement, and in the development of secondary sex characteristics. However, sexual precocity is rare in MAS males while isolated testicular enlargement is frequently observed. We recently reported the case of a boy with macro-orchidism and signs of Sertoli cell hyperactivity but no signs of hyperandrogenism, which was unexpected since Gs-alpha is functional in both Sertoli and Leydig cells. To understand its pathophysiology, we microdissected an available testicular biopsy to separate Sertoli from Leydig cells. The R201H-GNAS1 allele was present only in Sertoli cells, resulting in isolated Sertoli cell hyperfunction, evidenced by increased AMH expression and cell hyperplasia leading to prepubertal macro-orchidism, with no signs of Leydig cell activation. The different early embryologic origin of precursors contributing to Sertoli and Leydig cell lineages may underlie the differential existence of the mutated GNAS1 gene. Lack of occurrence of the mutation in Leydig cells may explain why sexual precocity is rarely observed in boys with MAS.