A fertility-oriented method for histological processing of testicular biopsies in men with azoospermia

ABSTRACT

The present study was designed to evaluate whether tissue preparation by glutaraldehyde and glycol methacrylate (G/GMA) improves the diagnostic assessment of testicular biopsies from azoospermic men when compared to the standard tissue preparation using Bouin’s solution and paraffin. We prospectively included a total of 21 testicular biopsies of sexually mature men aged 29–50 years with infertility and azoospermia. One testicular biopsy fragment from each patient was processed by the G/GMA method, whereas another tissue fragment was contemporarily processed by the conventional Bouin/paraffin (B/P) method. The G/GMA method provided better resolution of cytological details of the seminiferous epithelium, changing the final diagnosis in four cases. The medians of Bergmann’s spermatogenesis scores were 0.25 (interquartile range 0.04–0.88) for B/P preparations and 0.79 (interquartile range 0.17–0.96) for G/GMA preparations. Both techniques allowed accurate prediction of sperm recovery from the biopsies (B/P, area under the receiver operating characteristics [ROC] curve 0.88, 95% confidence interval [CI] 0.75–1.00; G/GMA, area under the ROC curve 0.94, 95% CI 0.86–1.00). We conclude that human testicular biopsy preparation with G/GMA improved image resolution under light microscopy and produced more reliable results for the evaluation of spermatogenesis in comparison with B/P, allowing a more precise fertility-oriented diagnosis in azoospermic men.

Abbreviations: B/P: Bouin/paraffin; GMA: glycol methacrylate; G/GMA: glutaraldehyde and glycol methacrylate; ICSI: intracytoplasmic sperm injection; OA: obstructive azoospermia; NOA: nonobstructive azoospermia; TESE: testicular sperm extraction.

KEYWORDS:

• Azoospermia
• infertility
• glycol methacrylate
• histology
• testicular biopsy

Authors’ Contributions

Designed the study and revised the manuscript: HCG, EST selected and operated the patients : ABR, RM performed the histological diagnoses: ABR, PGS; analyzed the images and produced the figures: FRCLA, WAA, ALCB analyzed the quantitative results and drafted the manuscript: ABR, FMR. All authors reviewed and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

Research supported by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq).