Modified stepwise mini-incision microdissection testicular sperm extraction: a useful technique for patients with a history of orchidopexy affected by non-obstructive azoospermia

Stepwise mini-incision microdissection testicular sperm extraction in NOA patients with a history of cryptorchidism: a case-control study

BACKGROUND

Although the orchiopexy is recommended for cryptorchidism to preserve male fertility, non-obstructive azoospermia (NOA) may occur in adulthood. Fortunately, a great many of azoospermic men may obtain sperm by microdissection testicular sperm extraction (mTESE). Due to the potential injuries caused by testicular diagnostic biopsy and vascular damage at the time of orchidopexy, minimal invasiveness is particularly important during mTESE, aims to reduce the surgical damage and avoids secondary testicular failure. This comparative study aims to investigate the efficacy of stepwise mini-incision mTESE technique by comparison with standard mTESE in the treatment of NOA patients with a history of cryptorchidism.

RESULTS

A total of 73 mTESE procedures were divided into two groups: Group 1 included 37 cases performed by stepwise mini-incision mTESE, while Group 2 included 36 cases with standard mTESE. The overall sperm retrieval rate (SRR) in the two groups was 68.5% (50/73), with no significant difference in SRR between Group 1 (78.4%, 29/37) and Group 2 (58.3%, 21/36) (P = 0.1). In addition, 46.0% of the patients (17/37) obtained sperm in the first mini-incision step in Group 1, which was also equal to an overall SRR in Group 2 (58.3%, 21/36) (P = 0.3). The operation time in Group 1 (72.6 ± 33.9 min) was significantly shorter than that in Group 2 (90.4 ± 36.4 min) (P = 0.04). Patients with an orchidopexy age no more than 10 years old had a higher SRR (79.5%, 31/39) than others (55.9%, 19/34) (P = 0.03). There were no postoperative complications including wound infection, scrotal hematoma, persistent pain, and testicular atrophy during a follow-up period of at least 6 months.

CONCLUSIONS

In conclusion, our study suggests that the stepwise mini-incision mTESE could be a promising approach for sperm retrieval in NOA men with a history of cryptorchidism. While the technique may potentially reduce operation time and surgical invasiveness, further research is needed to validate these findings on a larger scale. The results also suggest that age at orchidopexy may affect SRR and have important implications for the management of cryptorchidism.

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.

Flavonoid Metabolism in Tetrastigma hemsleyanum Diels et Gilg Based on Metabolome Analysis and Transcriptome Sequencing

Tetrastigma hemsleyanum Diels et Gilg, known as a "plant antibiotic", possesses several attractive properties including anti-inflammatory, anti-tumor, and antioxidant effects, with its efficacy being attributed to flavonoids. However, the flavonoid biosynthesis of T. hemsleyanum has rarely been studied. In this study, we investigated the flavonoid metabolism of T. hemsleyanum through metabolome analysis and transcriptome sequencing. The metabolomic results showed differences in the flavonoids of the leaves and root tubers of T. hemsleyanum. A total of 22 flavonoids was detected, and the concentrations of most flavonoids in the leaves were higher than those in the root tubers. Transcriptome analysis revealed that differentially expressed genes (DEGs) in the leaves and root tubers were enriched in photosynthesis-antenna proteins. Pearson correlation analysis indicated that the expression levels of chalcone isomerase (CHI) and UDP-glycose flavonoid glycosyltransferase (UFGT) were highly correlated with the concentrations of most flavonoids. Further, this study found that the photosynthesis-antenna proteins essentially contributed to the difference in the flavonoids in T. hemsleyanum. The gene expressions and concentrations of the total flavonoids of leaves and root tubers in Hangzhou, Jinhua, Lishui, and Taizhou in Zhejiang Province, China, showed that CHI (CL6715.Contig1_All, Unigene19431_All, CL921.Contig4_All) and UFGT (CL11556.Contig3_All, CL11775.Contig1_All) were the potential key genes of accumulation of most flavonoids in T. hemsleyanum.

Altered mRNAs Profiles in the Testis of Patients With "Secondary Idiopathic Non-Obstructive Azoospermia"

Background: Non-obstructive azoospermia (NOA) is the most severe form of male infertility. Currently, known causative factors, including congenital and several acquired causes only account for approximately 30% of NOA cases. The causes for NOA remain unclear for most patients, which is known as idiopathic (iNOA). However, whether iNOA is due to congenital defects or acquired abnormalities is a confusing problem due to the delayed diagnosis of this frustrating condition until the childbearing age. Therefore, we collected several cases with "secondary idiopathic NOA" and detected the altered mRNAs profiles in the testicular tissues to explore the possible molecular basis. Materials and Methods: In this study, several patients with a previous history of natural pregnancy with their partners before, who were diagnosed as iNOA based on the outcomes of routine semen analysis and multiple testis biopsies now, were enrolled. Some known risk factors and genetic factors were excluded. Therefore, we defined this phenotype as "secondary idiopathic NOA." To explore the possible molecular basis of this disease, we performed mRNA expression analysis through next-generation sequencing on three cases and other three patients with obstructive azoospermia as controls. Bioinformatics analyses were conducted to assess differentially expressed genes and possible biological mechanisms involved in the disease. Quantitative real-time reverse transcription polymerase chain reaction assays were applied to confirm the results in several selected mRNAs involved in stages and metabolism of Sertoli cells. Results: A series of mRNAs were found to be altered in testicular tissues between patients with "secondary idiopathic NOA" and controls, including 6,028 downregulated and 3,402 upregulated mRNAs. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genome (KEGG) analyses revealed a range of GO and KEGG terms, such as cellular process involved in reproduction, protein degradation, and absorption. Conclusion: The present study introduces a novel classification called "secondary idiopathic NOA." We provide a global view of the altered mRNAs involved in spermatogenetic failure in these cases. Regarding the limited samples, further studies should be taken to understand this new classification.

Novel variants in helicase for meiosis 1 lead to male infertility due to non-obstructive azoospermia

BACKGROUND

Non-obstructive azoospermia (NOA) is the most severe form of male infertility; more than half of the NOA patients are idiopathic. Although many NOA risk genes have been detected, the genetic factors for NOA in majority of the patients are unknown. In addition, it is difficult to retrieve sperm from these patients despite using the microsurgical testicular sperm extraction (microTESE) method. Therefore, we conducted this genetic study to identify the potential genetic factors responsible for NOA and investigate the sperm retrieval rate of microTESE for genetically deficient NOA patients.

METHODS

Semen analyses, sex hormone testing, and testicular biopsy were performed to categorize the patients with NOA. The chromosome karyotypes and Y chromosome microdeletion analyses were used to exclude general genetic factors. Whole exome sequencing and Sanger sequencing were performed to identify potential genetic variants in 51 patients with NOA. Hematoxylin and eosin staining (H&E) and anti-phosphorylated H2AX were used to assess the histopathology of spermatogenesis. Quantitative real time-polymerase chain reaction, western blotting, and immunofluorescence were performed to verify the effects of gene variation on expression.

RESULTS

We performed whole exome sequencing in 51 NOA patients and identified homozygous helicase for meiosis 1(HFM1) variants (NM_001017975: c.3490C > T: p.Q1164X; c.3470G > A: p.C1157Y) in two patients (3.9%, 2/51). Histopathology of the testis showed that spermatogenesis was completely blocked at metaphase in these two patients carrying the HFM1 homozygous variants. In comparison with unaffected controls, we found a significant reduction in the levels of HFM1 mRNA and protein expression in the testicular tissues from these two patients. The patients were also subjected to microTESE treatment, but the sperms could not be retrieved.

CONCLUSIONS

This study identified novel homozygous variants of HFM1 that are responsible for spermatogenic failure and NOA, and microTESE did not aid in retrieving sperms from these patients.

Evaluating the quality of reported outcomes for microsurgical TESE in men with non-obstructive azoospermia: A methodological analysis

BACKGROUND

Publications of microsurgical testicular sperm extraction (mTESE) techniques and outcomes are heterogeneous, which may limit creation of best surgical practices.

OBJECTIVE

To study the quality and heterogeneity of published mTESE outcomes via a methodological analysis.

MATERIALS/METHODS

A systematic methodological analysis of all published literature on the use of mTESE in men with non-obstructive azoospermia from 1999 to the July 2020 was performed. PubMed and MEDLINE searches were performed using the search terms "microdissection TESE OR microsurgical TESE." Publications were evaluated on their reporting of pre-operative factors, intraoperative techniques, surgical and clinical outcomes, and adverse events.

RESULTS

Fifty-five studies met inclusion criteria. Surgical technique and sperm retrieval rates were the most reported criteria. Reporting on the presence of an embryologist intraoperatively was observed in approximately 30% of articles, while other procedural details including method of sperm quantification, quantity retrieved, and number of cryopreserved vials were observed in fewer than 10% of articles. Clinical outcomes, including pregnancy rates and live birth rates, were reported in fewer than 40% of the articles. Fetal outcomes including fetal and neonatal anomalies were rarely reported. Fetal growth restriction, preterm delivery, small or large for gestational age, and NICU admissions were never reported.

CONCLUSION

There are inconsistencies in reporting quality of mTESE outcomes, specifically a lack of information on the quantity and quality of sperm retrieved, the role of embryology intraoperatively, and clinical outcomes, such as live birth rate and fetal anomalies. These gaps may guide development of standardized reporting guidelines to better assess and compare clinical outcomes across institutions and maintain focus on couples-centric fertility outcomes in future mTESE studies.

A novel homozygous mutation in the meiotic gene MSH4 leading to male infertility due to non-obstructive azoospermia

Non-obstructive azoospermia (NOA) is the most severe form of male infertility. Although some causes have been established, including genetic causes, the etiology in most cases remains idiopathic. Mutations in MSH4 (OMIM: 602105), an important gene involved in meiosis, may be related to female infertility due to primary ovarian insufficiency (POI) and male NOA. Here, we report a novel homozygous stop-gain mutation of MSH4 associated with NOA. Whole exome sequencing (WES) and bioinformatic analysis were performed in a patient with NOA from a consanguineous family (F1 II-1). A rare homozygous MSH4 stop-gain mutation (c.1552C>T:p.Q518X) was observed in the patient, and his parents were heterozygous carriers, as verified by Sanger sequencing. Testicular biopsy and hematoxylin and eosin staining of testicular tissue suggested meiotic arrest (MA), and no sperm were observed. MSH4 was detected in other 50 separate cases with same pathological results of MA using the same procedures, but only one heterozygous mutation was observed. Subsequent real-time quantitative polymerase chain reaction and immunohistochemistry were performed to examine mRNA expression levels and the localization of the MSH4 protein in the testicular tissue. Furthermore, the expression of MSH4 mRNA was significantly decreased compared with normal control. MSH4 protein was highly expressed in spermatocytes in the seminiferous tubules of the normal control, while no obvious expression was observed in F1 II-1. In this present study, MSH4 was identified as a candidate gene of male infertility causing NOA. A novel mutation of MSH4 (c.1552C>T:p.Q518X) is associated with the MA phenotype during spermatogenesis.