Obstructive Mechanism Lesions Simulating Primary Testicular Lesions

Abstract

Differentiation of obstructive azoospermia (OA) and nonobstructive azoospermia (NOA) is of paramount importance because their etiology, prognosis, and treatment are different. OA represents 40 % of the azoospermia cases. OA lesions are secondary to physical blocking of the spermatic ducts anywhere from rete testis to the ejaculatory ducts. The increase in intratubular hydrostatic pressure leads to injuries that are characterized by the variability with which the seminiferous tubules are affected. When no quantitative studies of the seminiferous epithelium are made, the single evaluation of the images of a few seminiferous tubules may be the cause of misinterpretation of lesions that are not infrequently confused with primary lesions, which naturally gives the lesions a different prognosis. Based on quantitative and qualitative studies, the following types of lesions secondary to an obstruction can be distinguished: young spermatid sloughing, late primary spermatocyte sloughing, early primary spermatocyte sloughing, and hypospermatogenesis associated with primary spermatocyte sloughing. In addition to these primary testicular lesions, those other lesions that most often lend to a differential diagnosis are discussed.