Brucella is a Gram-negative facultative intra cellular bacteria that is an important cause of epididymo-orchitis in endemic area
like Ardabil, Iran. The incidence of brucellosis in Ardabil is 10-21 in 100,000 population, but brucella epididymoorchitis incidence
is unknown .2-20% of brucellosis patients may have epididymoorchitis. Majority of Ardabil people live in rural area concord with
domestic animals like sheep, cow and goat. It seems that BEO incidence in Ardabil compared to developed countries or even other
provinces of Iran is higher. The incidence of brucella epididymo-orchitis in Ardabil province in Iran is widespread out of prospective.
BEO must be important acute scrotal pain differential diagnosis in alike endemic area.