Filarial orchitis: a cause of male infertility in the tropics--case report from Nigeria.

A young Nigerian male, previously well, presented with a three month history of unilateral orchitis and testicular pain which had failed to respond to conventional antimicrobial therapy. Exploration revealed non-specific epididymo-orchitis. Histology of testicles and peritesticular tissue/nodules showed testicular atrophy and granulomatous changes suggestive of filarial genital infection. There was marked spermatogenic arrest, and oligoasthenozoospermia. His blood contained microfilaria loa loa, and marked eosinophilia which returned to normal following diethylcarbamazine (DEC) therapy. His seminal fluid also showed improvement following this therapy. Evidence is presented from the literature for a possible link between filariasis and infertility in males.