The Histopathology of the Epididymis in a Group of Cases of Azoospermia with Normal Testicular Function

The histopathology of the head of the epididymis in cases of azoospermia associated with normal testicular function is described. In 2 specimens congenital absence of the vas deferens was associated with stuffing of all of the tubules with normal spermatozoa but no other abnormality. In 30 specimens from cases with idiopathic epididymal obstruction there were abnormalities in the vasa efferentia. These included both extreme narrowing of the lumen due to thickening of the wall by fibrosis and also distension of the lumen by sperm and degenerate debris. Small sperm granulomata were present in the tubular wall in 10 specimens and foreign body granulomata were present in 20 specimens. It is suggested that either persistent low grade infection, congenital abnormality or acute obstruction due to ischaemic or traumatic damage may be the initial lesion. If the infection or the obstruction is not speedily resolved, the condition may become self-perpetuating.