Autoimmune Orchitis

Subacute or chronic orchitis includes mainly non-infectious etiologies and also rarely autoimmune orchitis (AO). This urological condition is characterized by testicular inflammation with the presence of antisperm antibodies leading to immobilization and/or agglutination of spermatozoa, which blocks sperm–egg contact, with consequent infertility. AO may be primary (in the absence of other autoimmune diseases) or secondary (associated with another autoimmune condition, such as IgA vasculitis, Behçet’s disease, polyarteritis nodosa, IgG4-related disease, and others). This chapter reviews pathophysiology, clinical and laboratory features, diagnosis criteria, and treatment of AO.