Pre- and postoperative status of gonadotropins (FSH and LH) and inhibin-B in relation to testicular histopathology at orchiopexy in infant boys with unilateral undescended testes

The Inhibin-B Level at Orchidopexy and Follow-up of 280 Boys With Non-syndromic Unilateral Cryptorchid Testes

PURPOSE

An impaired germ cell number per tubular cross-section (G/T) at orchidopexy indicates a high risk of infertility. A recent study in boys with bilateral cryptorchidism showed a very high predictive value for a low serum inhibin-B level, indicating bilateral impaired G/T. Several other studies have shown a fairly strong correlation between inhibin-B and G/T. We aimed to evaluate if inhibin-B levels at orchidopexy improved at follow-up in boys with unilateral cryptorchidism.

METHODS

We included 280 boys with unilateral non-syndromic cryptorchidism at the median age of 1 year (4 months-9 years) who underwent orchidopexy. They were evaluated for serum FSH, LH and inhibin-B levels at surgery and at follow-up (median 16 months later), including multiple of the median (MoM) estimations of inhibin-B due to the age dependency of normal levels.

RESULTS

The inhibin-B MoM score improved significantly at follow-up. At orchidopexy, 59 (21%) boys had inhibin-B levels below the normal 2.5-percentile indicating impaired G/T bilaterally. At follow-up, 36% of the boys still had low inhibin-B. At orchidopexy, 221 (79%) boys had inhibin-B levels above normal 2.5-percentile and only 5% had low inhibin-B levels at follow-up. The risk of low inhibin-B levels at follow-up was significantly different between the two groups (p < 0.0001). At follow-up, totally, 32 (11%) boys had low inhibin-B levels, hereof only 3 patients with increased FSH.

CONCLUSIONS

Orchidopexy benefits the fertility potential. About 10% of boys with unilateral non-syndromic cryptorchidism may have a bilateral testicular disease reducing their fertility potential. Insufficient gonadotropin stimulation may possibly be the cause.

Management of the undescended testis in children: An American Pediatric Surgical Association Outcomes and Evidence Based Practice Committee Systematic Review

PURPOSE

Management of undescended testes (UDT) has evolved over the last decade. While urologic societies in the United States and Europe have established some guidelines for care, management by North American pediatric surgeons remains variable. The aim of this systematic review is to evaluate the published evidence regarding the treatment of (UDT) in children.

METHODS

A comprehensive search strategy and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were utilized to identify, review, and report salient articles. Five principal questions were asked regarding imaging standards, medical treatment, surgical technique, timing of operation, and outcomes. A literature search was performed from 2005 to 2020.

RESULTS

A total of 825 articles were identified in the initial search, and 260 were included in the final review.

CONCLUSIONS

Pre-operative imaging and hormonal therapy are generally not recommended except in specific circumstances. Testicular growth and potential for fertility improves when orchiopexy is performed before one year of age. For a palpable testis, a single incision approach is preferred over a two-incision orchiopexy. Laparoscopic orchiopexy is associated with a slightly lower testicular atrophy rate but a higher rate of long-term testicular retraction. One and two-stage Fowler-Stephens orchiopexy have similar rates of testicular atrophy and retraction. There is a higher relative risk of testicular cancer in UDT which may be lessened by pre-pubertal orchiopexy.

Leydig and Sertoli cell function in individuals with genital ambiguity, 46,XY karyotype, palpable gonads and normal testosterone secretion: a case-control study

BACKGROUND

Because normal male sexual differentiation is more complex than normal female sexual differentiation, there are more cases of disorders of sex development (DSDs) with 46,XY karyotype that have unclear etiology. However, Leydig and Sertoli cell markers are rarely used in distinguishing such individuals.

OBJECTIVES

To evaluate the function of Leydig and Sertoli cells in individuals with genital ambiguity, 46,XY karyotype, palpable gonads and normal testosterone secretion.

STUDY DESIGN AND SETTING

Case-control study with 77 patients, including eight with partial androgen insensitivity syndrome, eight with 5α-reductase deficiency type 2 (5ARD2) and 19 with idiopathic 46,XY DSD, and 42 healthy controls, from the Interdisciplinary Study Group for Sex Determination and Differentiation (GIEDDS), at the State University of Campinas (UNICAMP), Campinas, Brazil.

METHODS

Baseline levels of gonadotropins, anti-Müllerian hormone (AMH), inhibin B, insulin-like 3 (INSL3), testosterone and dihydrotestosterone in cases, and AMH, inhibin B, and INSL3 levels in controls, were assessed.

RESULTS

There was no significant difference in age between cases and controls (P = 0.595). AMH and inhibin B levels were significantly lower in cases than in controls (P = 0.031 and P < 0.001, respectively). INSL3 levels were significantly higher in cases than in controls (P = 0.003). Inhibin B levels were lower in 5ARD2 patients (P = 0.045) and idiopathic patients (P = 0.001), in separate comparisons with the controls.

CONCLUSION

According to our findings, we can speculate that inhibin B levels may be used to differentiate among DSD cases.

A narrative review of the history and evidence-base for the timing of orchidopexy for cryptorchidism

INTRODUCTION

Consensus recommendations for surgical management of cryptorchidism recommend orchidopexy between 6 and 18 months of age. The COVID-19 pandemic has impacted elective surgical scheduling.

OBJECTIVE

In response to the COVID-19 pandemic, we sought to review the available data regarding the natural history, surgical management, and infertility- and cancer-related risks associated with cryptorchid testes. The purpose of this review is to provide parents, referring providers, and surgeons with information to inform their decisions to proceed with or delay orchidopexy.

METHODS

A retrospective review and analysis of all available articles relevant to the natural history, surgical management, and infertility- and cancer-related risks of cryptorchidism present on PubMed, SCOPUS, and Cochrane Library was conducted.

RESULTS

The quality of historic literature pertaining to the effect of cryptorchidism on fertility and malignancy differ, with poorer data available on fertility. Cryptorchid testes may show histologic differences as early as birth, and some of these changes may have prognostic value in future fertility. Formerly unilateral cryptorchid men have slightly but not significantly reduced paternity rates compared to the general population. Cryptorchid testes have an increased risk of germ cell carcinogenesis, and robust data suggest the risk for malignancy in cryptorchid testes increases substantially after puberty.

CONCLUSION

The current body of evidence regarding the risks for future infertility and testicular cancer support the consensus recommendations for surgical correction of cryptorchidism between 6 and 18 months of age. During the uncertain time of the COVID-19 pandemic, decision for orchidopexy is a shared-decision between physician and parent. For an infant or young boy with a unilateral undescended testes, delaying orchidopexy several months until a time of decreased exposure risk is unlikely to result in substantial or sustained fertility or malignant risks.

Correlation between testicular volume and histological findings in children with unilateral cryptorchidism: Potential impact on future fertility

OBJECTIVES

Our aim is to assess the correlation between testicular volume and histological findings in children with unilateral cryptorchidism.

METHODS

From September 2016 to August 2018, from 60 patients surgically treated for cryptorchidism, 45 children were enrolled in this single-center prospective study. Depending on the degree of testicular volume reduction, patients were divided into Group 1 with <20% reduction and Group 2 with reduction ⩾20%. Patients underwent unilateral orchidopexy and simultaneous biopsy of the undescended testis. Tanner stage was assigned. Tubular Fertility Index was measured.

RESULTS

Group 1 included 20 patients (44.4%) and Group 2 included 25 patients (55.5%). Mean age was 2.10 years (range 12 months-3.8 years) in Group 1 and 2.8 years (range 18 months-4.41 years) in Group 2. Although there is a positive correlation between testicular volume and Tubular Fertility Index, no significant association was found between groups (p-value = 0.29). Furthermore, histological patterns did not differ significantly among groups.

CONCLUSIONS

The degree of volume reduction in undescended testis does not seem to correlate significantly with the severity of histological changes that accompany cryptorchidism. Tubular Fertility Index could serve as objective tool for the assessment of future fertility.

Fertility after the Operation of Cryptorchism in Childhood

Cryptorchism is a congenital anomaly of male genitalia, and is defined as a disorder of lowering testicles into the scrotum. In our study, the quality of sperm and fertility of men who were operated from unilateral or bilateral cryptorchism in childhood were analyzed. According to the age in which they were operated, patients were classified into different time groups, subjected to clinical examination and sperm analysis. A normal sperm count was found: 36.9% of the total number of patients operated from unilateral to bilateral cryptorchism. The highest percentage of normal sperm counts was 73.97%: the data which was found in the group that was operated from one-sided cryptorchism to the end of the second year of life. Regardless of the age of the cryptorchism operation, it is possible to expect a disorder of spermatogenesis.

Gonocyte transformation in congenital undescended testes: what is the role of inhibin-B in cell death?

PURPOSE

Undescended testes (UDT) are subjected to heat stress, which can disturb gonocyte transformation as well as apoptosis. This study aims to describe the apoptosis pathway occurring during minipuberty of children with unilateral (UDT), and to investigate the role of inhibin-B.

METHODS

Testicular biopsies at unilateral orchidopexy of 10 boys (6-9 months old) with normal inhibin-B (n = 5) or low inhibin-B (n = 5) were selected for immunohistochemistry and TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labelling) assay. Testicular tubules were labelled with antibodies against Anti-Müllerian hormone (AMH, Sertoli cell marker), mouse Vasa Homolog (MVH) and placental alkaline phosphatase (PLAP) (both germ cell markers), cleaved caspase3 (apoptotic marker), and followed by confocal imaging and cell counting with Fiji/ImageJ. Data were analyzed with GraphPad Prism.

RESULTS

In males with low and normal inhibin-B, there was no statistical difference (p > 0.05) in the percentage of testicular tubules containing TUNEL + cells, number of cleaved caspase3 ± germ cells/tubule, total number of germ cells/tubule, and the percentage of fibrotic tubules or number of Sertoli cells/tubule.

CONCLUSIONS

These results suggest that inhibin-B does not regulate cell death of gonocytes and further studies are required to uncover any role of inhibin-B in gonocyte transformation.

Impaired serum inhibin-B and number of germ cells in boys with cryptorchidism following heavily gestational maternal smoking

PURPOSE

A meta-analysis including 11,900 cases showed that maternal gestational smoking was associated with increased risk of cryptorchidism. The aim of study was to investigate whether a hormone profile of cryptorchid boys and a supplementing histopathological evaluation of testicular biopsies could add detailed knowledge to the impact of maternal gestational smoking on pathogenesis of cryptorchidism.

METHODS

601 cryptorchid boys aged 4 months to 14 years old were included. Because normal hormones have a pronounced age dependency, we compared results from boys whose mothers had smoked heavily (>10 cigarettes/day) during pregnancy with age matched cryptorchid controls of nonsmoking mothers (1:6). We studied: birthweight, germ-cell number/tubular cross section, frequency of germ cells positive for placental-like alkaline phosphatase (PLAP), gonadotropins and inhibin-B.

RESULTS

501 boys were sons of nonsmokers, 72 boys of intermittent smokers and 28 boys of heavy smokers. 39%, 44% and 61% respectively had bilateral cryptorchidism. Compared to age-matched cryptorchid controls of nonsmoking mothers, sons of heavy smokers had lower birthweight (p = 0.006), germ-cell number/tubular cross section (p = 0.009), frequency of germ cells positive for PLAP (p = 0.037) and inhibin-B (p = 0.042).

CONCLUSIONS

All findings could be associated with placental dysfunction with altered human chorionic gonadotropin production well described in women smoking during pregnancy.

TYPE OF STUDY

Prognosis study (prospective cohort study with >80% follow-up).

LEVEL OF EVIDENCE

Level 1.

Surgical Management of Undescended Testis - Timetable and Outcome: A Debate

Around 1.4-3.8% of boys in the Western world are operated because of cryptorchidism. This means that orchidopexy remains one of the most common surgical procedures performed in boys. As a consequence, several consensus reports, guidelines, and reviews dealing with the management of cryptorchidism have been published recently. Based on our research and 30 years' experience with the management of cryptorchidism, the intention of the present publication is to advise on the surgical management and comment on the expected outcome, especially with focus on the controversies related to guidelines and reviews. Except for late referral and waiting lists, which may be practical problems, there is no reason to postpone orchidopexy for nonsyndromic congenital cryptorchid testes beyond 6 months. There is good evidence that such strategy improves the fertility potential and decreases the risk of testicular cancer. In cases with genuine gonadotropin insufficiency, early surgical correction is not enough and adjuvant LH-RH treatment should be implemented to improve the fertility potential. Cryopreservation may be an option in case of treatment failure of adjuvant LH-RH. A prerequisite for such management includes serum hormone assessment and evaluation of testicular biopsies at orchidopexy. Ascended testes contribute to 20-60% of operative cases and should be treated when diagnosed.

Hypogonadism and Cryptorchidism

Congenital cryptorchidism (undescended testis) is one of the most common congenital urogenital malformations in boys. Prevalence of cryptorchidism at birth among boys born with normal birth weight ranges from 1.8 to 8.4%. Cryptorchidism is associated with a risk of low semen quality and an increased risk of testicular germ cell tumors. Testicular hormones, androgens and insulin-like peptide 3 (INSL3), have an essential role in the process of testicular descent from intra-abdominal position into the scrotum in fetal life. This explains the increased prevalence of cryptorchidism among boys with diseases or syndromes associated with congenitally decreased secretion or action of androgens, such as patients with congenital hypogonadism and partial androgen insensitivity syndrome. There is evidence to support that cryptorchidism is associated with decreased testicular hormone production later in life. It has been shown that cryptorchidism impairs long-term Sertoli cell function, but may also affect Leydig cells. Germ cell loss taking place in the cryptorchid testis is proportional to the duration of the condition, and therefore early orchiopexy to bring the testis into the scrotum is the standard treatment. However, the evidence for benefits of early orchiopexy for testicular endocrine function is controversial. The hormonal treatments using human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) to induce testicular descent have low success rates, and therefore they are not recommended by the current guidelines for management of cryptorchidism. However, more research is needed to assess the effects of hormonal treatments during infancy on future male reproductive health.

Comparison between two inhibin B ELISA assays in 46,XY testicular disorders of sex development (DSD) with normal testosterone secretion

BACKGROUND

Inhibin B is a hormone produced by the Sertoli cells that can provide important information for the investigation of disorders of sex development (DSD) with 46,XY karyotype. The aim of this study is to compare two enzyme-linked immunosorbent assay (ELISA) assays for dosage of serum inhibin B in patients with 46,XY DSD with normal testosterone secretion.

METHODS

Twenty-nine patients with 46,XY DSD and normal testosterone secretion (partial androgen insensitivity syndrome [PAIS] [n=8]; 5α-reductase deficiency [n=7] and idiopathic 46,XY DSD [n=14]) were included. Molecular analysis of the AR and SRD5A2 genes were performed in all patients and the NR5A1 gene analysis in the idiopathic group. Measurements of inhibin B were performed by two second-generation ELISA assays (Beckman-Coulter and AnshLabs). Assays were compared using the interclass correlation coefficient (ICC) and the Bland-Altman method.

RESULTS

ICC was 0.915 [95% confidence interval (CI): 0.828-0.959], however, a discrepancy was observed between trials, which is more evident among higher values when analyzed by the Bland-Altman method.

CONCLUSIONS

It is recommended to perform the inhibin B measurement always using the same ELISA kit when several evaluations are required for a specific patient.

Prospective study of histological and endocrine parameters of gonadal function in boys with cryptorchidism

INTRODUCTION

A transient increase in gonadotropins and testosterone during mini-puberty causes gonocytes to differentiate into Ad spermatogonia, which establish male germ cell memory and male-specific DNA methylation pathways. Over half of patients with unilateral cryptorchidism and the majority of patients with bilateral cryptorchidism display an abnormal spermiogram, which indicates that unilateral cryptorchidism is a bilateral disease; therefore, it represents a serious andrological problem. The aim of this study was to evaluate relationships between hormonal parameters and testicular biopsy findings in boys with cryptorchidism.

METHOD

Seventy-one boys (median age 15 months; range 7-65 months) who underwent orchidopexy (24% had bilateral cryptorchidism) were tested for serum LH, FSH, and inhibin B. With ipsilateral testis biopsy histology, we determined the tubular fertility index (TFI), Ad spermatogonia counts, and Ad/tubular index (Ad/T). We compared age groups (<18 vs. >18 months old); groups with and without Ad spermatogonia; groups with unilateral and bilateral cryptorchidism; and extreme groups with high infertility risk (HIR; n = 12; TFI <0.2; Ad/T = 0) and low infertility risk (LIR; n = 9; TFI >0.9; Ad/T>0.02).

RESULTS

Of the specimens, 38% had no Ad spermatogonia. Age was significantly negatively correlated with TFI and Ad/T, but positively correlated with FSH. Median LH values were significantly higher in LIR than in HIR groups. Unilateral and bilateral cryptorchidism showed similar TFI, Ad/T, and hormone concentrations. The areas under ROC curves for FSH, LH, and inhibin B (0.66, 0.601, and 0.599, respectively) showed low diagnostic value for predicting HIR (no Ad spermatogonia).

CONCLUSION

Our observation of lower plasma LH levels in the group with the most pronounced testicular pathology was the opposite of what we would have expected if testicular pathological changes were caused by a primary gonadal defect. Therefore, low plasma LH levels in the HIR group confirmed the notion that this group of patients with cryptorchidism had hypogonadotropic hypogonadism. The estimated incidence of defective mini-puberty in boys with cryptorchidism could be as high as 50%. Testicular biopsies from boys with cryptorchidism lacked Ad spermatogonia. Fertility parameters worsened with age. Significantly lower basal LH in the HIR group indicated hypogonadotropic hypogonadism. Serum hormone levels could not predict histological biopsy findings.

The Sertoli cell hormones inhibin-B and anti Müllerian hormone have different patterns of secretion in prepubertal cryptorchid boys

OBJECTIVES AND HYPOTHESES

The Sertoli-cells produce inhibin-B and Anti-Müllerian-Hormone (AMH). Much is still unknown about these hormones in prepubertal cryptorchids. The Sertoli-cells are mandatory for germ cell development. The aim of the study was to investigate if there are differences in secretion pattern of Sertoli-cell hormones and their gonadotropin feed-back mechanisms.

METHODS

Included were 94 prepubertal cryptorchid boys 0.5-13.1years with measurements of serum-inhibin-B, Anti-Müllerian-Hormone (AMH), Luteinizing Hormone (LH) and Follicle Stimulation Hormone (FSH). The serum values were measured using commercially available kits. The hormonal values were related to age-matched normal values. Testicular biopsy was taken at orchiopexy.

RESULTS

Inhibin-B positively correlated to AMH for 1-13year-old patients (p<0.0001), but not for 0.5-1year-old patients (p=0.439). For 0.5-1year-old patients inhibin-B-values tended to decrease (p=0.055), in contrast to AMH-values (p=0.852). LH was elevated more often than FSH (p=0.014). FSH and LH were positively associated in patients both 0.5-1year (p=0.042) and 1-13years of age (p<0.0001). LH correlated positively to inhibin- B (p=0.001). In contrast, FSH did not correlate to inhibin-B or AMH (p=0.755 and p=0.528). The number of A-dark spermatogonia per tubular transverse section was positively correlated to inhibin-B serum level.

CONCLUSION

Our new finding of an association between LH and inhibin-B in infancy of cryptorchid boys may be essential for the transformation of gonocytes to A-dark spermatogonia. Previously, LH associated to inhibin-B was described in early puberty only. During the first year of life inhibin-B values decreased faster than AMH. The AMH-levels may just reflect the increased Sertoli cell number that occurs during the first 3months of life.