The role of the gubernaculum in the descent and undescent of the testis

Alterations in testicular positioning after normal descent: acquired cryptorchidism

BACKGROUND

Acquired cryptorchidism or acquired undescended testis (UDT) is defined as the displacement of a testicle outside the scrotal sac after normal descent has been verified. There are still no clear guidelines on its management.

OBJECTIVES

To analyze patients who underwent surgery for UDT in our setting to determine the prevalence of acquired cryptorchidism and to analyze the demographic and clinical characteristics of the population of children diagnosed with both acquired and congenital cryptorchidism, the age of presentation of both entities and the percentage of bilateral involvement.

MATERIALS AND METHODS

This was a retrospective descriptive study using data from the clinical history of patients who underwent surgery for cryptorchidism between 2011 and 2022. The type of cryptorchidism, acquired or congenital, was recorded. Demographic and clinical data were collected.

RESULTS

A total of 367 patients and 442 testicular units were included in the study (75 patients had bilateral involvement). In 54.75% (95% CI: 50.09%-59.40%) of the cases analyzed, cryptorchidism was acquired, and the mean age at the time of surgery was 7.39 years (SD 2.95). Twenty percent (95% CI: 16.29%-24.58%) of the patients presented with bilateral cryptorchidism and 64% (95% CI: 52.88%-75.11%) out of them were acquired on both sides. The diagnosis was metachronous in 42.6% (95% CI: 31.21%-54.12%) of bilateral cryptorchidism cases.

DISCUSSION AND CONCLUSION

Acquired cryptorchidism accounts for more than half of cryptorchidism cases requiring surgery in our setting, with a clearly different age of presentation than that for congenital cryptorchidism. Therefore, it is necessary to monitor the presence of the testes in the scrotal sac until adolescence. It is also important to monitor patients with a history of cryptorchidism, not only for the management of the operated testicle but also for the early identification of patients who will develop metachronous contralateral cryptorchidism.

Diagnosis, Classification, and Contemporary Management of Undescended Testicles

This article provides a comprehensive review regarding undescended testicles and other related conditions. We have included background information summarizing variable clinical presentations, epidemiology, and the implications of undescended testis (UDT) on fertility and malignancy risk. This article has an emphasis on the approach to diagnosis and surgical management for the UDT. The purpose of this review is to provide readers with useful clinical tools for assessing and treating patients with cryptorchidism.

A rare case of a toddler with unilateral cryptorchidism-related cranial suspensory ligament remnant

Key clinical message

Several animal experiment studies have shown that insufficient testicular descent to the scrotum can be caused by persistence of cranial suspensory ligament (CSL). We report a case of right cryptorchidism in a male toddler surgically treated with an orchidopexy possibly associated with CSL persistence based on intraoperative and pathological findings. This case would be a precious source to further investigate the etiopathogenesis of cryptorchidism.

Abstract

The CSL anchors embryonic gonads to the dorsal abdominal wall during antenatal mammalian development. Although its persistence appears to cause cryptorchidism in animal models, it has never been proven in humans. A 1-year-old boy with right cryptorchidism underwent right orchidopexy. Intraoperatively, a band-like structure running from the right testis into the retroperitoneum and up to the right side of the liver was noticed and resected. The pathological findings of the specimen showed fibrous connective tissues, smooth muscles, and blood vessels but no tissues suggestive of a testis, a spermatic cord, an epididymis, or liver. Immunohistochemical analysis for an androgen receptor antibody did not detect any signal in the specimen. The right cryptorchidism in this case was possibly caused by CSL persistence, which is the first such human case, to our knowledge.

Testicular descent revisited: a micro-computed tomography study in fetal rats

PURPOSE

There is a long history of research dealing with the embryology of the testicular descent. However, important aspects like the role of the gubernaculum and the development of the processus vaginalis peritonei are not understood. Micro-computed tomography (µCT) is an established tool for anatomical studies in rodents. Our study applied µCT imaging to visualize the testicular descent in rats and focused on the role of the gubernacular bulb and the development of the processus vaginalis peritonei.

METHODS

Rats from embryonic day 15 (ED15) to ED21 and newborns (N0) were fixed and dried using the "critical point" technique. We ran a SkyScan^® µCT system and scans were analyzed for gender-specific differentiation of the genital ridge and used for 3D visualization of relevant anatomic structures.

RESULTS

µCT imaging confirmed the intraperitoneal location of the testicles from ED15 to N0. The components of the inner genital moved closer together while the intestinal volume expanded. The gubernacular bulb seemed to be involved in the formation of the processus vaginalis peritonei.

CONCLUSION

Here, we utilized µCT imaging to visualize the testicular descent in the rat. Imaging provides new morphologic aspects on the development of the processus vaginalis peritonei.

The curious case of testicular descent: factors controlling testicular descent with a note on cryptorchidism

Background

The testicular descent is a uniquely complex process depending upon multiple factors like growth and reorganisation of the specific gonadal ligaments, hormones, etc., which interplay with each other. Though an unambiguous event, it is still laced with incredulity since the data interpretation were intermingled between different species creating more ambiguity in certain aspects of this process. In order to understand the aetiopathology of cryptorchidism the extensive study of the factors controlling the descent is necessitous.

Main body

Though testes originate in the abdomen, they migrate to an extra abdominal site the scrotum, which makes it vulnerable to pathological conditions associated with the descent. The hormones that play vital role in the first phase of descent are insulin-like hormone 3 (INSL3), Anti-müllerian hormone as well as testosterone, whereas androgens, genitofemoral nerve and its neurotransmitter calcitonin gene-related peptide (CGRP) influence the second phase. Despite the vast research regarding the complex nexus of events involving the descent there are disparities among the cross species studies. However all these discrepancies make testicular descent yet again fascinating and perplexing. Our aim is to provide a comprehensive review including recent advances which provides thorough coverage of anatomical and hormonal factors in the descent as well as cryptorchidism.

Conclusion

Though our understanding on testicular descent has evolved over the decades there still has obscurity surrounding it and the studies on the factors responsible for descent are becoming more intense with the time. Our knowledge on many factors such as INSL3 and CGRP is more established now; however, on the other hand the role of androgens still remains speculative. As the knowledge and understanding of the biological process of testicular descent increases it will pave ways to new treatment plans to treat cryptorchidism more effectively.

Laparoscopic staged management of high intrabdominal testis: A prospective randomized study

OBJECTIVE

To prospectively compare outcomes and complications of both staged laparoscopic techniques used in management of high intrabdominal testis (IAT).

MATERIALS AND METHODS

Forty five patients were included in the study in whom unilateral high IAT were identified and were subjected to two-stage laparoscopic orchiopexy. Patients were prospectively randomized into two groups according to laparoscopic technique in use; either two stage Fowler-Stephens laparoscopic orchiopexy (FSLO) or staged laparoscopic traction orchiopexy (SLTO). Intraoperative evaluation for the distance of the testis from the internal ring, state of the internal ring (closed or open), operative time (min), intraoperative and early postoperative complications were recorded after first stage. Surgical outcomes of both techniques included operative time, intraoperative complications, success rate, final scrotal site position, testicular size and vascularity, and these were recorded within 48h of the second stage procedure and at 6 month follow-up.

RESULTS

Staged FSLO was performed on 25 testes. Four cases were lost during follow up. Out of these 21 cases, one child had an atrophic testis before the second stage based on previously recorded operative size. SLTO was done on 20 testes. We had 2 cases of fixation suture slippage rendering a total of 18 patients who underwent second stage operation. No patients converted from laparoscopic to open surgery. At 6 month follow-up visits, 27 testes were found on examination to have a low scrotal position, (14 in the FSLO group and 13 in the SLTO group), 9 testes in high scrotal position (5 in the FSLO group and 4 in the SLTO group). Testicular ascent occurred in one patient in each group. Testicular atrophy was identified in 3 cases among the FS group, while no case of testicular atrophy occurred in the traction group of patients (p = 0.048).

CONCLUSIONS

Both staged laparoscopic techniques had comparable success rates as regard final scrotal position for high undescended IAT in children, and were associated with no intra or post operative complications. SLTO had a better outcome as it was not associated with any testicular atrophy compared to FSLO at 6 months follow up.

The G-Protein-Coupled Membrane Estrogen Receptor Is Present in Horse Cryptorchid Testes and Mediates Downstream Pathways

Cryptorchidism in horses is a commonly occurring malformation. The molecular basis of this pathology is not fully known. In addition, the origins of high intratesticular estrogen levels in horses remain obscure. In order to investigate the role of the G-protein-coupled membrane estrogen receptor (GPER) and establish histological and biochemical cryptorchid testis status, healthy and cryptorchid horse testes were subjected to scanning electron microscopy analysis, histochemical staining for total protein (with naphthol blue black; NBB), acid content (with toluidine blue O; TBO), and polysaccharide content (with periodic acid-Schiff; PAS). The expression of GPER was analyzed by immunohistochemistry and Western blot. GPER-mediated intracellular cAMP and calcium (Ca2+) signaling were measured immunoenzymatically or colorimetrically. Our data revealed changes in the distribution of polysaccharide content but not the protein and acid content in the cryptorchid testis. Polysaccharides seemed to be partially translocated from the interstitial compartment to the seminiferous tubule compartment. Moreover, the markedly decreased expression of GPER and GPER downstream molecules, cAMP and Ca2+, suggests their potential role in testis pathology. Increased estrogen levels in cryptorchid conditions may be linked to disturbed GPER signaling. We postulate that GPER is a prominent key player in testis development and function and may be used as a new biomarker of horse testis in health and disease.

Structural and functional significance of scrotal ligament: a comparative histological study

Gubernaculum testes is the most important parameter in testicular migration. At the end of migration, it is described as scrotal ligament, which has implications in testicular torsion. The present study aims to examine the structure of scrotal ligament and compare it with gubernaculum. Sixteen adult cadaveric testicular specimens and fourteen fetal testicular specimens of different age groups were examined after getting ethical clearance from the institute ethics committee and consent from the parents. Meticulous dissection was done. The length, site of proximal, and distal attachment of scrotal ligament and gubernaculum were noted and histologically evaluated. A separate scrotal ligament could not be delineated in any adult specimens. It merged with testicular coverings. Histological examination showed the presence of patchy areas of dense collagen fibres of variable density amidst loose areolar connective tissue. In contrast, fetal specimens showed the presence of a definitive gubernaculum testes and revealed the presence of mesenchymal tissue, collagen, elastic fibres, and myocytes which varied according to gestational age of fetuses. Structure of scrotal ligament and gubernaculum testes is highly variable. Description of scrotal ligament as a firm attachment from lower pole of testes to scrotum is controversial, questioning its role as protective factor in testicular torsion.

Clinically Differentiated Abnormalities of the Architecture and Expression of Myosin Isoforms of the Human Cremaster Muscle in Cryptorchidism and Retractile Testis

AIM

To describe architecture and expression of myosin isoforms of the human cremaster muscle (CM) and to individuate changes in clinically differentiated abnormalities of testicular descent: cryptorchidism or undescended testis (UDT) and retractile testis (RT).

BACKGROUND

The CM is a nonsomitic striated muscle differentiating from mesenchyme of the gubernaculum testis. Morphofunctional and molecular peculiarities linked to its unique embryological origin are not yet completely defined. Its role in abnormalities of testicular descent is being investigated.

SUBJECTS AND METHODS

Biopsy samples were obtained from corrective surgery in cases of cryptorchidism, retractile testis, inguinal hernia, or hydrocele. Muscle specimens were processed for morphology, histochemistry, and immunohistology.

RESULTS AND CONCLUSIONS

The CM differs from the skeletal muscles both for morphological and molecular characteristics. The presence of fascicles with different characterization and its myosinic pattern suggested that the CM could be included in the specialized muscle groups, such as the extrinsic ocular muscles (EOMs) and laryngeal and masticatory muscles. The embryological origin from the nonsomitic mesoderm is, also for the CM, the basis of distinct molecular pathways. In UDT, the histological alterations of CM are suggestive of denervation; the genitofemoral nerve and its molecular messengers directed to this muscle are likely defective. Compared with the other samples, RT has a distinct myosinic pattern; therefore, it has been considered a well-defined entity with respect to the other testicular descent abnormalities.

An extremely rare case of indirect hernia type co-existing with testicular ectopia

We present an extremely rare case of inguinal hernia coexisting with testicular ectopia in a child. Male infant 9.5 month old presented with an empty scrotum and the ipsilateral intravaginal testis lying in a high iliac crest position. When crying a moving right inguinal bulge appeared on clinical examination. This grew bigger in moments of increased abdominal pressure and seemed to move upwards towards the right ileac crest. No abdominal wall defect could be palpated. At operation a large hernia sac fixed in the area of the right iliac crest was identified. Adjacent was the fixation point of the gubernaculum and the testis was found in an ectopic location. We removed the large sac after separating the vas and vessels and the testis and we strengthened the dorsal inguinal wall and fixed the testis in a subdartos scrotal pouch. No postoperative complications happened. An undescended testis may present as an iliac crest ectopy, coexisting with moving inguinal hernia. In our case we propose that the higher position of the aponeurosis of the external oblique in combination with ectopia of gubernacular fixation in the ipsilateral scrotum may have caused the ectopic fixation of the sac in the ipsilateral inguinal crest.

Oral contraceptive use and genital anomalies in sons. A Danish cohort study

Exposure to exogenous sex hormones with estrogenic or anti-androgen properties may influence intrauterine development of male genitals. This population-based cohort study based on data from 44,408 live-born singleton sons in the Danish National Birth Cohort (DNBC) aimed to investigate whether maternal use of oral contraceptives prior to or during early pregnancy increase the risk of cryptorchidism or hypospadias. We found no consistent association between use of oral contraceptives and cryptorchidism or hypospadias, neither in those exposed any time four months prior to conception [cryptorchidism: adjusted Odds Ratio (aOR): 1.06 (95% CI: 0.91; 1.23), hypospadias: 0.74 (95% CI: 0.53; 1.03)] nor in those exposed any time during the first trimester of pregnancy [cryptorchidism: aOR: 0.93 (95% CI: 0.53; 1.62), hypospadias: 1.02 (95% CI: 0.32; 3.23)]. Despite relatively strong exposure levels from oral contraceptive use in pregnancy, this study revealed no evidence of an increased risk of either two genital malformations.

Alteration of androgen receptor expression, apoptosis and cell proliferation in cryptorchid suckling, nursery and growing-finishing pigs

Cryptorchidism, a condition of one or two undescended testicles, is a common congenital disease in pigs, causing loss in the pig industry. One of the major factors affecting testicular descent is the androgen receptor (AR), which binds to androgen and then regulates the expression of androgen-responsive genes in the inguinoscrotal phase of testicular descent. AR expression has been reported to regulate apoptosis in testicular stem cells. The present study aimed to immunohistochemically examine AR and Ki-67 protein expression and apoptosis detection in unilateral undescended testicles (UDT) and descended testicles in cryptorchid pigs (DT) of suckling (aged 1-2 weeks), nursery (aged 6 weeks) and growing-finishing pigs (aged 12, 15 and 20 weeks) and in normal testicles (NT) at 1-2 and 12 weeks of age. At 1-2 weeks, decreased expression of AR was observed in UDT and DT compared with NT and was lower than that at 6-20 weeks. The expression of Ki-67, a marker of cell proliferation, in UDT and DT at 12 weeks was lower than that in NT at the same age. In addition, Ki-67 expression in UDT at 6 and 12 weeks was lower than that in UDT at 1-2 and 15-20 weeks. More testicular apoptosis was revealed in UDT at 1-2 weeks than in DT and NT at the same age. At 15-20 weeks, more apoptosis was detected in UDT than in DT. Positive correlation of AR expression in DT at 6 and 12 weeks was also noted, in addition to the association of the expression of AR and Ki-67 in NT at 12 weeks. Taken together, this study unveiled the low expression of AR and high apoptosis detection in UDT, whereas low expression of AR and low apoptosis detection were noted in DT in suckling piglets. Diminished cell proliferation was shown in UDT at 6-12 weeks, whereas high apoptosis was observed in UDT at 15-20 weeks. High expression of AR was shown only in nursery pigs. Distinct expression of AR in DT and NT at 1-2 and 12 weeks indicated that both conditions were not interchangeable.

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.

Is genetic drift to blame for testicular dysgenesis syndrome in Semliki chimpanzees (Pan troglodytes schweinfurthii)?

BACKGROUND

We present 3 likely cases of testicular dysgenesis syndrome (TDS) within a community of chimpanzees (Pan troglodytes schweinfurthii). We tested whether genetic drift may be the culprit, as a genetic cause has been suspected to account for TDS among other wildlife.

METHODS

We successfully sequenced a 367-bp segment spanning the first hypervariable region within the D-loop of the mitochondrial genome for 78 DNA samples.

RESULTS

We found 24 polymorphic sequence sites consisting of 7 singletons and 17 parsimony informative sites. This sample contained 9 haplotypes with a diversity index of 0.78 (SD = 0.03). All tests against the null hypothesis of neutral polymorphisms were non-significant (P > .10). The mismatch distribution of pairwise differences does not fit a Poisson's curve (raggedness index = 0.166; SSD = 0.12; P = 1).

CONCLUSIONS

Thus, we found no significant signs of genetic isolation, population expansion, or genetic bottleneck. Alternative causes of TDS and how they might pertain to this population are discussed.

The Role of the Appendix Testis in Normal Testicular Descent: Is There a Connection?

Objective

The presence of testicular appendices was prospectively evaluated in 89 boys with 96 undescended testes who underwent orchidopexy over the period of 4 years.

Results

The patients were divided into two groups. Group A included 42 boys with 49 undescended testes positioned close to the internal inguinal ring, and Group B included 47 boys with 47 undescended testes close to the external inguinal ring. The incidence of appendix testis (AT) in Group A was 57.1% (28 in 49) and 78.7% (37 in 47) in Group B. The results of our study showed significantly decreased incidence of testicular appendices in undescended testes positioned close to the internal inguinal ring compared with undescended testes positioned close to the external inguinal ring (p < 0.05).

Conclusion

AT may play a role in normal testicular descent and the undescended testis positioned close to the external inguinal ring can be considered as a separate entity of the true congenital undescended testis.

Anatomy and histology of the scrotal ligament in adults: inconsistency and variability of the gubernaculum testis

PURPOSE

The anatomy of gubernaculum testis (GT) is often discussed; however, the postnatal anatomy of the GT or scrotal ligament (SL) is rarely described. Hence, we performed an anatomical and histological study to analyze histologically the structures between testis and scrotum.

METHODS

We performed anatomical dissections on 25 human fresh cadavers' testes. Each testis was removed with its envelopes and macroscopically analyzed. Then samples were included for histological study. Finally, they were analyzed under microscope, looking for attachments between testis, epididymis and scrotal envelopes.

RESULTS

The absence of proximal and distal attachment was found in 56.0% of cases. Looking at the proximal attachment of the SL, the main one found is the epididymal attachment (28.0%), whereas no cases of testis attachment was found. Distally, there are more variations with scrotal attachment (12%) and cremaster attachment (12.0%). We found a significant prevalence of multiple adherences in 16.0% of cases too. Finally, in 15 cases (57.7%) an attachment is present between testis and epididymis, as it is commonly described.

CONCLUSIONS

In the majority of cases there is no attachment of the lower pole of the testis and epididymis and these structures remain free. So it seems that the SL disappears with aging. Moreover, there is not only one kind of ligamentous attachment, but a high variability of attachments at the lower pole of the testiculo-epididymal structure. When it exists, this structure is never a real ligament and it seems more appropriate to use the term "attachments".

The management of boys under 3 months of age with an inguinal hernia and ipsilateral palpable undescended testis

AIMS

The optimal management for boys under 3 months of age with an indirect inguinal hernia (IIH) and ipsilateral palpable undescended testis (IPUDT) is unknown. We aimed to: 1) determine the current practice for managing these boys across the UK, and 2) compare outcomes of different treatment strategies.

METHODOLOGY

We undertook two studies. Firstly, we completed a National Survey of all surgeons on the British Association of Paediatric Surgeons email list in 2014. Subsequently, we undertook a multi-centre, retrospective, 10-year (2005-2015) review across 4 pediatric surgery centers of boys under 3months of age with concomitant IIH and IPUDT. Primary outcome was testicular atrophy. Secondary outcomes included need for subsequent orchidopexy, testicular ascent and hernia recurrence. Data are presented as median (range). Chi-squared test and multivariate binomial logistic regression analysis were used for analysis; p<0.05 was considered significant.

RESULTS

Survey: Consultant practice varies widely across the UK, with a tendency towards performing concurrent orchidopexy at the time of herniotomy under 3 months of age. Concurrent orchidopexy is favored less in cases where the hernia is symptomatic. Case Series Review: Forty-one boys with 43 concomitant IIH and IPUDT were identified, and all included. 32 (74%) hernias were reducible, 11 (26%) were symptomatic requiring urgent or emergency repair. Post-conceptual age at surgery was 45weeks (36-65). Primary operations included: 29 (67%) open hernia repair and standard orchidopexy, 8 (19%) open hernia repair with future orchidopexy if required, 4 (9%) laparoscopic hernia repair with future orchidopexy if required, 2 (5%) open hernia repair and suturing of the testis to the inverted scrotum without scrotal incision. Variation in atrophy rate between different surgical approaches did not reach statistical significance (p=0.42). Overall atrophy rate was 18%. If hernia repair alone was undertaken (8 open and 4 laparoscopic), the testis did not descend in 8 patients, requiring subsequent orchidopexy (67%); if orchidopexy was undertaken at the time of hernia repair, 1 in 29 required a repeat orchidopexy (3%) (p=0.0001). No hernia recurred.

CONCLUSION

This study suggests that orchidopexy at the time of inguinal herniotomy does not increase the risk of testicular atrophy in boys under 3months of age.

An inguinal hernia with cryptorchidism with a Leydig cell tumor in an elderly man: A case report

INTRODUCTION

Cryptorchidism is common in children but is rare in the elderly. It often presents with a constellation of signs and symptoms similar to routine inguinal hernias. We present the case of an elderly man with cryptorchidism containing a Leydig cell tumor and provide clinical insights.

PRESENTATION OF CASE

An-84-year old man was admitted with an incarcerated right lower quadrant hernia. Both testes were absent on palpation of the scrotum. After reduction of the hernia, computed tomography scan revealed a round lesion in the hernia sac, which was suspected to be the ectopic testis. Laparoscopic exploration was performed in combination with an open anterior approach. The hernia orifice was the right internal inguinal ring, and the inguinal canal was obliterated by adhesions because the spermatic cord did not pass through it. The ectopic testis was resected with the hernia sac, and the hernia repaired with a KUGEL™ patch (Bard, USA).

DISCUSSION

Laparoscopic exploration was useful to delineate the anatomy of this unusual inguinal hernia. The open anterior approach was necessary to dissect the ectopic testis and the hernia sac. Pathological findings revealed tumor cells with clear cytoplasm in the resected testis, diagnosed as a Leydig cell tumor.

CONCLUSION

The combination of laparoscopic and anterior approaches facilitated the surgical treatment of an unusual inguinal hernia with cryptorchidism. The resected ectopic testis should undergo thorough histopathologic examination.

Placental Weight and Male Genital Anomalies: A Nationwide Danish Cohort Study

The most consistently reported risk indicators for the male genital anomalies cryptorchidism and hypospadias are prematurity and low birth weight. Placental dysfunction has been hypothesized as a possible underlying cause, and an association between placental weight at birth and hypospadias has been indicated. In a population-based cohort of 388,422 Danish singleton boys born alive (1997-2008), we studied the association between placental weight and cryptorchidism and hypospadias. Missing data were handled with multiple imputation, and we estimated hazard ratios by means of Cox regression models. During follow-up, 1,713 boys were diagnosed with hypospadias and 6,878 with cryptorchidism (3,624 underwent corrective surgery). We observed an association between low placental weight and risk of both genital anomalies. Boys with a placental weight in the lowest decile (<10%) had higher risks of both cryptorchidism (hazard ratio = 1.52, 95% confidence interval: 1.31, 1.76) and hypospadias (hazard ratio = 1.97, 95% confidence interval: 1.59, 2.45) than boys in the reference decile (50.0-59.9%). In conclusion, we found higher risks of both genital malformations in boys born with a low placental weight. The relationship seemed stronger for hypospadias than for cryptorchidism. Taken together, our data support a role for placental dysfunction in the etiology of these anomalies.

Staged rotation flap scrotoplasty and orchidopexy in a patient with inguinal ectopic scrotum

Ectopic scrotum is a rare and unusual presentation to paediatric urology. It is usually characterized by accessory scrotum with adequate scrotum in the anatomically normal position. We describe a case of inguinal ectopia of the right hemiscrotum containing the right testis, and its staged surgical management by rotation flap scrotoplasty and subsequent orchidopexy.

Diethylstilbestrol affects the expression of GPER in the gubernaculum testis

Recent evidence suggested a positive correlation between environmental estrogens (EEs) and high incidence of abnormalities in male urogenital system. EEs are known to cause the abnormalities of testes development and testicular descent. Diethylstilbestrol (DES) is a nonsteroidal synthetic estrogen that disrupts the morphology and proliferation of gubernacular cells, and its nongenomic effects on gubernaculum testis cells may be mediated by G protein-coupled estrogen receptor (GPER). In this study, we detected the expression of GPER in mouse gubernacular testis and investigated the effects of DES on the expression of GPER in gubernaculum testis cells. RT-PCR analysis revealed that GPER mRNA was expressed in the gubernaculum. GPER protein was detected in the parenchymal cells of the gubernaculum early in development. Furthermore, we demonstrate that GPER inhibitor G15 relieved DES-induced inhibition of GPER expression in gubernaculum testis cell, but ER inhibitor ICI 182780 had the converse effects on DES-induced inhibition of GPER expression in these cells. These data suggest that the effects of DES on mouse gubernaculum testis cells are mediated at least partially by the regulation of GPER expression.

Cryptorchidism and infertility in rats with targeted disruption of the Adamts16 locus

A Disintegrin And Metalloproteinase with ThromboSpondin motifs16 (ADAMTS-16) is a member of a family of metalloproteinases. Using a novel zinc-finger nuclease based gene-edited rat model harboring a targeted mutation of the Adamts16 locus, we previously reported this gene to be linked to blood pressure regulation. Here we document our observation with this model that Adamts16 is essential for normal development of the testis. Absence of Adamts16 in the homozygous Adamts16^mutant males resulted in cryptorchidism and male sterility. Heterozygous Adamts16^mutant males were normal, indicating that this is a recessive trait. Testes of homozygous Adamts16^mutant males were significantly smaller with significant histological changes associated with the lack of sperm production. Temporal histological assessments of the testis demonstrated that the seminiferous tubules did not support active spermatogenesis, but progressively lost germ cells, accumulated vacuoles and did not have any sperm. These observations, taken together with our previous report of renal abnormalities observed with the same Adamts16^mutant rats, suggest an important mechanistic link between Adamts16 and the functioning of the male genitourinary system.

Indirect inguinal hernia sac containing testis and spermatic cord in an adult patient with cryptorchidism

Sliding hernias are those in which part of the sac wall is formed by a retroperitoneal organ and/or its mesentery protruding outside the abdominal wall cavity. The hernia sac may contain jejunum, ileum, vermiform appendix, Meckel's diverticulum, stomach, ovary, fallopian tube or urinary bladder. Our report features an adult case with cryptorchidism in which testis and spermatic cord constitute a component of the indirect inguinal hernia sac.

Molecular signals governing cremaster muscle development: clues for cryptorchidism

BACKGROUND/AIM

Cryptorchidism affects 2-4% of newborn boys. Testicular descent requires the gubernaculum to differentiate into cremaster muscle (CM) during androgen-mediated inguino-scrotal descent, but the cellular mechanisms regulating this remodeling remain elusive. β-Catenin, a marker of canonical Wnt signaling, promotes myogenic genes and cellular adhesion. We aimed to determine if androgen receptor (AR) blockade altered β-catenin and its downstream myogenic proteins within the CM.

METHOD

Gubernacula from male rats (n=12) and rats treated with anti-androgen, flutamide (n=12) at E19, D0, D2 were processed for immunohistochemistry. Antibodies against β-catenin, embryonic myosin, and myogenin were visualized by confocal microscopy.

RESULTS

At E19, β-catenin immuno-reactivity (IR) localized to the CM membrane. By D2, cytoplasmic β-catenin-IR was noted with overall β-catenin-IR decreasing. Myogenic proteins resided primarily in cells containing β-catenin on their plasma membrane. Embryonic myosin-IR was high at E19 and then decreased by D2, while myogenin-IR increased. AR blockade increased cytoplasmic β-catenin at D2 and reduced levels of both myogenic proteins.

CONCLUSION

Myogenic proteins are present in CM cells containing β-catenin. AR blockade did not alter cellular adhesion via β-catenin. In contrast, blocking AR prevented β-catenin entering the nucleus and impaired CM myogenesis. Mutations in this pathway may result in idiopathic cryptorchidism.

Testicular outcome following laparoscopic second stage Fowler-Stephens orchidopexy

OBJECTIVE

To assess outcome after laparoscopic second-stage Fowler-Stephens orchidopexy (L2(nd)FSO).

PATIENTS AND METHODS

Retrospective review of 94 children (aged 0.75-16 years, median 2.75 years), who underwent L2(nd)FSO for 113 intra-abdominal testes between January 2000 and May 2009: 75 unilateral, 19 bilateral (11 synchronous; 8 metachronous). Follow-up (range 3 months-10.9 years, median 2.1 years) was available for 88 children (102 testes: 71 unilateral, 31 bilateral).

RESULTS

Testicular atrophy occurred in 9 out of 102 (8.8%), including 8 out of 71 (11.3%) unilateral and 1 out of 31 (3.2%) bilateral intra-abdominal testes (multivariate analysis: p = 0.59). Testicular ascent ensued in 9 out of 102 (8.8%), comprising four (5.6%) unilateral and five (16.1%) bilateral testicles (multivariate analysis: p = 0.11). Of the 18 bilateral testes brought to the scrotum synchronously none atrophied and four (22.2%) ascended, compared to one (7.7%) atrophy and one (7.7%) ascent among the 13 testes brought to the scrotum on separate occasions (Fisher exact test: p = 0.42 and p = 0.37, respectively). Mobilization of the testis through the conjoint tendon tended towards less ascent (multivariate analysis p = 0.08) but similar atrophy (p = 0.56) compared to mobilization through the deep-ring/inguinal canal. Logistical regression analysis identified no other patient or surgical factors influencing outcome.

CONCLUSIONS

This is the largest series of L2(nd)FSO to date. A successful outcome is recorded in 85 out of 102 (83.3%) testicles. Atrophy occurred in 8.8% and ascent in 8.8%.

The regulation of testicular descent and the effects of cryptorchidism

The first half of this review examines the boundary between endocrinology and embryonic development, with the aim of highlighting the way hormones and signaling systems regulate the complex morphological changes to enable the intra-abdominal fetal testes to reach the scrotum. The genitoinguinal ligament, or gubernaculum, first enlarges to hold the testis near the groin, and then it develops limb-bud-like properties and migrates across the pubic region to reach the scrotum. Recent advances show key roles for insulin-like hormone 3 in the first step, with androgen and the genitofemoral nerve involved in the second step. The mammary line may also be involved in initiating the migration. The key events in early postnatal germ cell development are then reviewed because there is mounting evidence for this to be crucial in preventing infertility and malignancy later in life. We review the recent advances in what is known about the etiology of cryptorchidism and summarize the syndromes where a specific molecular cause has been found. Finally, we cover the recent literature on timing of surgery, the issues around acquired cryptorchidism, and the limited role of hormone therapy. We conclude with some observations about the differences between animal models and baby boys with cryptorchidism.

Male reprotoxicity and endocrine disruption

Mammalian reproductive tract development is a tightly regulated process that can be disrupted following exposure to drugs, toxicants, endocrine-disrupting chemicals (EDCs), or other compounds via alterations to gene and protein expression or epigenetic regulation. Indeed, the impacts of developmental exposure to certain toxicants may not be fully realized until puberty or adulthood when the reproductive tract becomes sexually mature and altered functionality is manifested. Exposures that occur later in life, once development is complete, can also disrupt the intricate hormonal and paracrine interactions responsible for adult functions, such as spermatogenesis. In this chapter, the biology and toxicology of the male reproductive tract is explored, proceeding through the various life stages including in utero development, puberty, adulthood, and senescence. Special attention is given to the discussion of EDCs, chemical mixtures, low-dose effects, transgenerational effects, and potential exposure-related causes of male reproductive tract cancers.