Functional and cytologic features of the contralateral testis in cryptorchidism

Case report: Comprehensive evaluation and management of male infertility with complete AZFC microdeletion and undescended testicle

This case report presents a 31-year-old male patient with primary infertility, a unilaterally undescended testicle, and a complete AZFc microdeletion. Despite failed attempts at testicular sperm extraction, the patient underwent successful microscopic testicular sperm extraction and subsequent viable sperm extraction, leading to successful fertilization through intracytoplasmic sperm injection (ICSI). The report underscores the potential for successful ICSI in male infertility cases with complex genetic and reproductive issues, highlighting the importance of comprehensive genetic evaluation and individualized reproductive techniques in managing male infertility associated with undescended testicle and genetic anomalies.

Azoospermic Men with a History of Cryptorchidism Treated by Orchiopexy Have Favorable Outcomes after Testicular Sperm Extraction: A Systematic Review and Meta-Analysis

PURPOSE

This systematic review and meta-analysis investigated the sperm retrieval rate (SRR) and pregnancy rate after testicular sperm extraction in men with azoospermia and those with a history of cryptorchidism treated by orchiopexy.

MATERIALS AND METHODS

The SRR and clinical pregnancy rate were investigated. We performed a sub-analysis that included factors such as bilaterality, age, and idiopathic non-obstructive azoospermia (iNOA). The analysis comprised 13 studies from January 1995 to July 2021. The data sources were PubMed/MEDLINE, Embase, and the Cochrane Library included "cryptorchidism", "orchidopexy", "azoospermia", and "testicular sperm extraction".

RESULTS

The overall mean SRR was 63.3% (95% confidence interval [CI], 57.6%-68.6%; I²=62.4%), and the overall mean clinical pregnancy rate was 30.1% (95% CI, 22.6%-38.8%; I²=69.9%). The meta-analysis comparing the SRR, there was no significant difference between patients with a history of bilateral and unilateral orchiopexy (relative risk [RR]=1.02; 95% CI, 0.89-1.16; p=0.79). Orchiopexy performed under the age of 10 years showed significantly increased SRR compared to the age of over 10 years (RR=1.25; 95% CI, 1.06-1.47; p=0.008). Azoospermic men with a history of cryptorchidism treated by orchiopexy had significantly higher SRR than iNOA (RR=1.90; 95% CI, 1.40-2.58; p<0.0001).

CONCLUSIONS

Men with azoospermia and a history of cryptorchidism treated by orchiopexy had significantly higher SRR than those with iNOA after testicular sperm extraction. Furthermore, patients who underwent orchiopexy before the age of ten years had significantly higher SRR than patients operated at an older than the age of ten years.

Perspectives in Pediatric Pathology, Chapter 14. Natural History of Undescended Testes

Cryptorchidism is one of the most frequent problems encountered in pediatric urology. Its causes, associated lesions, and prognosis in terms of fertility have been a source of interest and discrepancies for pediatric pathologists and urological surgeons.

Reductions in calcitonin gene-related peptide may be associated with the impairment of the contralateral testis in unilateral cryptorchidism

The aim of the present study was to investigate the mechanism underlying the impairment of the contralateral testis in unilateral cryptorchidism in experimental rats using a molecular neurophysiological approach. Thirty-six male rats (21 days old) were divided into a cryptorchidism group, a cryptorchidism with division of the genitofemoral nerve (GFN) group and a control group (n=12/group). The distribution of the calcitonin gene-related peptide (CGRP) immunoreactive nerve fibers in the testes was studied using an immunohistochemistry technique. Germ cell apoptosis was detected using the terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling method. The concentration of malondialdehyde (MDA) in the testis tissue was evaluated using a spectrophotometric determination method, and the ultrastructure of Sertoli cells was observed using transmission electron microscopy. It was found that, 100 days after the surgery, the concentration of CGRP in the cryptorchidism group was decreased significantly, whereas the levels of MDA and the number of apoptotic germ cells were increased significantly compared with the control group (P<0.01). Following the division of the GFN, the damaging effects were decreased (P<0.01). The impairment mechanism may therefore be associated with a reduction in the level of CGRP in the contralateral testis. The reflex decrease in CGRP may be caused by germ cell apoptosis, decreased blood flow and oxygen levels, and the increase in reactive oxygen free radicals and lipid peroxidation.

Association between two single nucleotide polymorphisms of interleukin-27 gene and increased cryptorchidism risk

Growing evidences have suggested the association between interleukin-27 and cryptorchidism. We aimed to investigate the relationship between IL-27 polymorphisms and cryptorchidism susceptibility. A total of 519 males were enrolled in a case-control study (150 cases and 369 normal subjects). The variants were discriminated using polymerase chain reaction-restriction fragment length polymorphism methods. The proportions of the major allele for rs153109 and rs17855750 were A and T with frequencies of 0.56 and 0.85 in cases and 0.51 and 0.91 in controls respectively (P values = 0.002, P value = 0.002). The heterozygous genotype of rs153109 and 17855750 was A/G and T/G with frequencies of 0.62 and 0.25 in cases and 0.39 and 0.17 in controls respectively (P values <0.001, P values <0.001). The A allele and A/G genotype of rs153109 polymorphisms contribute to increase cryptorchidism susceptibility, and G allele and T/G genotype of rs17855750 also contribute to increase cryptorchidism susceptibility, which implies that these allele and genotypes may be risk factors for the development of cryptorchidism.

SURGICAL VS. UNTREATED CRYPTORCHIDISM: EFFECTS ON FERTILITY

Forty-four patients with history of cryptorchidism were studied: 15 untreated (group A); 14 treated by orchiopexy at age 4.5 +/- 1.4 years (group B), and 15 with unilateral orchiectomy of undescended testis at 8.4 +/- 1.6 years (group C). Testicular volume, semen analysis, and LH and FSH were measured. Normal sperm counts were noted in 53%, 36% and 47% of patients in groups A, B and C, respectively. FSH and LH serum levels showed no differences between the groups. Testicular volume of the normal descended testes showed no differences between the three groups. Positive correlation was obtained between testicular volume/sperm concentration and negative correlation between gonadotropins/sperm concentration. The remaining testicular volume and gonadotropin serum values from adults with history of chryptorchidism who underwent orchiectomy were not different from those orchiopexied treated nor with untreated patients. The percentage of men with sperm count greater than 20 millions/mL was lower in the orchiopexied men compared to A and C groups. There seems to be different etiologic factors in our patients.

DOES ORCHIDOPEXY REVERT THE HISTOLOGICAL ALTERATIONS IN EPIDIDYMAL AND VAS DEFERENS CAUSED BY CRYPTORCHIDISM?

Cryptorchidism is a pathological condition in which the testicles are retained in the abdominal cavity, resulting in atrophic seminiferous tubules. Some gross structural abnormalities and histological altercations have been described in the epididymis and vas deferens in humans with cryptorchidic testes. Orchidopexy surgery restores testicular spermatogenesis in experimental and clinical procedures, but it is still unclear whether histological changes in the epididymis and vas deferens caused by cryptorchidism may be reverted by orchidopexy. The aim of this study was to evaluated the histological changes in the epididymis and vas deferens following experimental uni- bilateral cryptorchidism in mature and immature mice, and to determine whether altercations could be reversed by orchidopexy. Young and adult C57 BL6 mice were randomized into three groups: control mice, bi/unilaterally cryptorchidic mice and bilaterally cryptorchidic mice with orchidopexy. After evaluation of testis, epididymis and vas deferens, there were no histological alterations in contralateral epididymis of mice unilaterally cryptorchidic. Ipsilateral epididymis of unilaterally cryptorchidic mice and epididymis from bilaterally cryptorchidic mice showed significant histological alterations. Orchuidopexy resorted normal spermatogenesis and the histological features of epididymis. It would appear that persistent male infertility clinically observed after orchidopexy could not be related to histological alteration in the testis and epididymis. Development and maintenance of the vas deferens seems to be controlled independently of the epididymis since it was not altered by cryptorchidism condition.

Role of hormones, genes, and environment in human cryptorchidism

Cryptorchidism is the most frequent congenital birth defect in male children (2-4% in full-term male births), and it has the potential to impact the health of the human male. In fact, although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. Furthermore, some reports have highlighted a significant increase in the prevalence of cryptorchidism over the last few decades. Etiology of cryptorchidism remains for the most part unknown, and cryptorchidism itself might be considered a complex disease. Major regulators of testicular descent from intraabdominal location into the bottom of the scrotum are the Leydig-cell-derived hormones testosterone and insulin-like factor 3. Research on possible genetic causes of cryptorchidism has increased recently. Abundant animal evidence supports a genetic cause, whereas the genetic contribution to human cryptorchidism is being elucidated only recently. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene have been recognized as causes of cryptorchidism in some cases, but some chromosomal alterations, above all the Klinefelter syndrome, are also frequently involved. Environmental factors acting as endocrine disruptors of testicular descent might also contribute to the etiology of cryptorchidism and its increased incidence in recent years. Furthermore, polymorphisms in different genes have recently been investigated as contributing risk factors for cryptorchidism, alone or by influencing susceptibility to endocrine disruptors. Obviously, the interaction of environmental and genetic factors is fundamental, and many aspects have been clarified only recently.

Hormonal and genetic control of testicular descent

Cryptorchidism has the potential to affect the health of the human male. Although it is often considered a mild malformation, it represents the best-characterized risk factor for reduced fertility and testicular cancer. The aetiology of cryptorchidism remains, for the most part, unknown and cryptorchidism itself might be considered a complex disease. This reflects the intricate mechanisms regulating testicular development and descent from intra-abdominal location into the bottom of the scrotum, involving different anatomical and hormonal factors. Major actors of testicular descent are the Leydig cell-derived hormones testosterone and insulin-like factor 3, even if other factors may play a role. Although considerable evidence exists in animals to support a genetic cause, the genetic contribution to human cryptorchidism is only recently being elucidated. Environmental factors might also contribute to the aetiology of cryptorchidism and its increased incidence in recent years. Mutations in the gene for insulin-like factor 3 and its receptor and in the androgen receptor gene explain a minority of cases of cryptorchidism, but research on genetic polymorphisms that may also influence susceptibility to endocrine disruptors is shedding light on this field.

Paracrine and endocrine roles of insulin-like factor 3

Insulin-like factor 3 (INSL3) is expressed in Leydig cells of the testis and theca cells of the ovary. This peptide affects testicular descent by acting on gubernaculum via its specific receptor leucine-rich repeat-containing G protein-coupled receptor 8 (LGR8). From initial animal data showing the cryptorchid phenotype of Insl3/Lgr8 mutants, an extensive search for mutations in INSL3 and LGR8 genes was undertaken in human patients with cryptorchidism, and a frequency of mutation of 4-5% has been detected. However, definitive proofs of a causative role for some of these mutations are still lacking. More recent data suggest additional paracrine (in the testis and ovary) and endocrine actions of INSL3 in adults. INSL3 circulates at high concentrations in serum of adult males and its production is dependent on the differentiation effect of LH. Therefore, INSL3 is increasingly used as a specific marker of Leydig cell differentiation and function.

Preliminary data suggest that mutations in the CgRP pathway are not involved in human sporadic cryptorchidism

In testicular descent to the scrotum, a multistep process, many anatomical and hormonal factors play a role. Cryptorchidism occurs in about 1-2% of males and may cause secondary degeneration of the testes. Animal models have shown that abnormalities, in the calcitonin gene-related peptide (CgRP) activity, could be relevant in the pathogenesis of cryptorchidism. We performed a mutation screening by PCR exon amplification, single-strand conformation polymorphism (SSCP) and sequencing in four candidate genes, CgRPs (alphaCgRP, betaCgRP), their receptor (CgRPR) and the receptor component protein (CgRP-RCP), in 90 selected cases of idiopathic unilateral or bilateral cryptorchidism. Mutation screening of the coding regions and intron-exon boundaries revealed some polymorphic variants but no pathogenic sequence changes. These preliminary data suggest that these genes are not major factors for cryptorchidism in humans.

Analysis of the DAZ gene family in cryptorchidism and idiopathic male infertility

OBJECTIVE

To investigate whether partial deletions of the DAZ gene family on the Y chromosome are associated with cryptorchidism, similar to that found for complete AZF deletions.

DESIGN

Prospective study.

SETTING

University hospital.

PATIENT(S)

A total of 193 azoospermic and severely oligozoospermic men: 95 with a history of cryptorchidism and 98 classified as idiopathic.

INTERVENTION(S)

A two-part study for Y chromosome microdeletions was performed: a polymerase chain reaction (PCR)-based analysis for complete AZF deletions and partial DAZ gene analysis by PCR-restriction digestion assay for single-family variants.

MAIN OUTCOME MEASURE(S)

Presence and type of AZF deletions and number of DAZ genes present.

RESULT(S)

The frequency of complete AZF deletions was similar in idiopathic (13.3%) and cryptorchid men (11.6%), but partial DAZ deletions were found only in infertile subjects without cryptorchidism (7.1%). The testicular phenotype was similar in men with complete AZF deletions and partial DAZ deletions, therefore the contribution of the other AZF genes in determining the spermatogenic impairment is still unclear.

CONCLUSION(S)

Our findings suggest that the loss of only some copies of DAZ is sufficient to lead to severe male infertility, but it is not a frequent finding in cryptorchid men.

Absence of microdeletions in the Y chromosome in patients with Prader-Willi syndrome with cryptorchidism

Unilateral or bilateral cryptorchidism is found in 80-100% of male patients with Prader-Willi syndrome (PWS). Recently, the relationship between Yq deletions and cryptorchidism has been assessed. However, the relationship between Yq deletions and PWS patients with cryptorchidism remains unclear. Polymerase chain reaction (PCR) amplification of 51 DNA loci encompassing all of the regions for azoospermia factor (AZF) of the Y chromosome, including the deleted in azoospermia (DAZ) and ribonucleic acid-binding motif (RBM) genes, were examined for microdeletions in 10 PWS males with cryptorchidism and 20 healthy control male subjects. No microdeletions of 51 loci were found in any of the PWS males. The present study therefore suggests that microdeletions in the AZF regions of the Y chromosome do not relate to the occurrence of cryptorchidism in PWS patients.

Different insulin-like 3 (INSL3) gene mutations not associated with human cryptorchidism

Cryptorchidism is the most frequent congenital anomaly of the urogenital tract in the male, but its etiology is for the most part unknown. Evidence suggests that a possible genetic cause may be involved. Animal models support this hypothesis, and in particular INSL3 (Leydig insulin-like 3 hormone) has been proposed as putative gene for cryptorchidism, since male mice mutant for Insl3 exhibit bilateral abdominal cryptorchidism due to alteration of gubernaculum development. In this study, we analyzed whether mutations in INSL3 could be associated with human cryptorchidism. Heteroduplex analysis and sequencing of both exons of INSL3 in 65 ex-cryptorchid patients and a group of control subjects allowed us to find four nucleotide changes in the sequence of exon I. These mutations are all single base substitutions from G to A at position 27, 96, 126 and 178. Only the 178G-->A substitution changes codon 60 from alanine to threonine (A60T). All mutations were found in comparable distribution in ex-cryptorchid patients and non-cryptorchid men. Therefore, all mutations represent neutral polymorphisms not associated with phenotype. This study confirms previous observations and demonstrates a novel polymorphism in the INSL3 gene. In contrast to that described for the mutant mouse, these data indicate that mutations of INSL3 do not seem to represent a frequent cause of cryptorchidism.

Prenatal measurement of testicular diameter by ultrasonography: development of fetal male gender and evaluation of testicular descent

Prenatal ultrasonography has evolved through advancements in imaging technology and observer experience. The purpose of the present study was to evaluate fetal testicular descent and diameter in relation to gestational age. A prospective cross-sectional study on 331 fetuses from an unselected population underwent a detailed assessment of testicular descent and diameter at 20-40 weeks' gestation by means of transabdominal sonography (91.2%) and transvaginal sonography (8.8%) when necessary. Fetal gender was identified in the transverse and sagittal planes and maximum testicular diameter was measured. The mean testicular diameter (in millimeters) per week and the 95% confidence interval (CI) were defined. Testicular descent was not observed prior to 23 weeks' gestation, with 6.6% of the fetuses having one testis descended at 23 weeks and 98.2% after 32 weeks. A linear relationship between testicular diameter and gestational age was observed. The present results chart the time course for testicular descent and provide a centile chart for fetal testicular diameter from 25 to 40 weeks' gestation. These findings may aid prenatal diagnosis of associated abnormal conditions as well as investigations into the clinical finding of abnormal testicular size.

Ultrastructural study of the boar seminiferous epithelium: changes in cryptorchidism

The present study compares the ultrastructural features of Sertoli cells and germ cells between scrotal testes of healthy boars and abdominal testes of unilateral and bilateral cryptorchid boars. In healthy boars, spermatogonia are flat cells lying in close association with the basal lamina. As differentiation progresses, spermatogonia acquire an oval profile and lose their contact with the basal lamina. Spermatocytes are round cells moving from the basal compartment of the seminiferous epithelium to the luminal compartment. Spermatids exhibit complex morphological changes leading to the formation of spermatozoa. Sertoli cells extend from the basal lamina to the tubular lumen. The nucleus encloses fine euchromatin and one or two nucleoli; the nuclear envelope has a few deep infoldings. The lateral cell membranes form junctional specializations that constitute the blood-testis barrier. The cytoplasm encloses smooth endoplasmic reticulum, vesicles, aggregates, and scattered mitochondria. The seminiferous epithelium of abdominal testes from unilateral and bilateral cryptorchid boars contains few spermatogonia with an abnormal appearance; the alteration in germ cell number is more severe in the bilateral disease. In unilateral cryptorchid boars, spermatogonia appear as either large pyramidal cells or roundish cells; in bilateral cryptorchid boars, spermatogonia show roundish profiles and degenerative patterns. Abdominal testes of both unilateral and bilateral cryptorchid boars are constituted by immature Sertoli cells that show abnormal cytoplasmic content, defective development of the blood-testis barrier, and atypical nuclear appearance; in bilateral cryptorchid boars, immature Sertoli cells exhibit degenerative signs. At postpubertal age, unilateral and bilateral cryptorchidism induce total arrest of spermatogenesis at spermatogonial stage as a result of an abnormal differentiation of the Sertoli cells. Moreover, the degeneration of abdominal testes initiates earlier in bilateral cryptorchidism than in unilateral cryptorchidism.

Efficiency of the process of meiosis in scrotal testes of healthy boars and unilateral abdominal cryptorchid boars

Unilateral abdominal cryptorchidism has usually been correlated with abnormalities in the spermatogenic activity of the scrotal testis. The present study describes the effects of unilateral abdominal cryptorchidism on the meiotic process in scrotal testes from postpubertal boars. The percentage of primary spermatocytes, secondary spermatocytes, and round spermatids was evaluated in testicular smears from scrotal testes of healthy boars and of right-sided unilateral abdominal cryptorchid boars. As compared to the scrotal testes of healthy boars, the scrotal testes of unilateral abdominal cryptorchid boars showed low transformation from primary to secondary spermatocytes (meiosis I), but normal transformation from secondary spermatocytes to round spermatids (meiosis II). The data obtained indicate that spontaneous unilateral abdominal cryptorchidism on the right side induced partial arrest of spermatogenesis at the primary spermatocyte stage that was attributed to anomalies in Sertoli-cell activity. Abnormal paracrine signals from altered Sertoli cells could have resulted in either disturbed mitosis, which led to the formation of spermatocytes with an abnormal DNA content, or abnormalities in the metabolic activity and the organization of the cytoskeleton of primary spermatocytes.

Y chromosome microdeletions in cryptorchidism and idiopathic infertility

To clarify whether cryptorchidism might be the expression of an intrinsic congenital testicular abnormality, we investigated the frequency of Y chromosome long arm (Yq) microdeletions in unilateral excryptorchid subjects manifesting an important bilateral testiculopathy. Microdeletion analysis of Yq was performed by polymerase chain reaction in the following subjects: 40 unilateral excryptorchid patients with azoospermia or severe oligozoospermia due to a bilateral severe testiculopathy (Sertoli cell-only syndrome or severe hypospermatogenesis); 20 unilateral excryptorchid men with moderate oligozoospermia and a normal testicular cytological picture in the contralateral testis; 110 patients affected by idiopathic severe primary testiculopathies; 20 patients affected by idiopathic moderate testiculopathy; and, as controls, 50 patients affected by known causes of testiculopathy and 100 fertile men. Eleven of 40 (27.5%) unilateral excryptorchid patients affected by bilateral testiculopathy and 28 of 110 (25.4%) patients affected by idiopathic severe primary testiculopathy showed Yq microdeletions, whereas no microdeletions were found in all the other subjects, nor in male relatives of patients with deletions. Microdeletions were located in different parts of Yq, including known regions involved in spermatogenesis (DAZ and RBM, AZFa, b, and c) and other loci still poorly defined. No difference in localization of deletions was evident between cryptorchid and idiopathic patients. Microdeletions in Yq may be responsible for severe bilateral testicular damage that could be phenotypically expressed by unilateral cryptorchidism, as well as by idiopathic infertility.