Testicular morphology

The most severe alteration of spermatogenesis is characterized by complete sclerotization, where no cells are present in the seminiferous tubules. In terms of severity, this alteration is followed by complete aplasia of germ cells, SCOS or del Castillo's syndrome, where the seminiferous tubules are usually reduced in diameter. Another severe alteration is complete spermatogenic maturation arrest at the spermatocyte level, characterized by a normal population of Leydig's and Sertoli's cells, spermatogonia and spermatocytes, but an absence of spermatids and spermatozoa. Infrequently, maturation arrest can be observed at the spermatogonia or round spermatid level. In the latter cases, mature or elongated spermatids are absent. Less severe forms of spermatogenic alteration include hypospermatogenesis (proportional decrease in all spermatogenic cells), partial maturation arrest, focal SCOS and mixed patterns.

The estimated prevalence of non-obstructive azoospermia, determined by testicular biopsy, ranges between 40% and 60% [5]. For standardization, the use of scoring systems [6,7] is strongly suggested (Tables 5, 6).

Table 5. Scoring system for testicular biopsies - Johnsen score [6]

Table 6. Scoring system for testicular biopsies (Holstein score [7])

No seminiferous epithelial cells, tubular sclerosis

No germ cells, Sertoli cells only

3.___________ Spermatogonia only

_4.___________ No spermatids, few spermatocytes, arrest at primary spermatocyte stage

5.___________ No spermatids, many spermatocytes

6.___________ Few early spermatids, disturbance of spermatid differentiation

7.___________ No late spermatids, many early spermatids

Few late spermatids

9.___________ Many late spermatids, disorganized tubular epithelium

10. Full spermatogenesis

Typical findings for the history and physical examination of a patient with non-ohstructive acoospermia are listed in Tables A and B.

Date: 2016-06-12; view: 293