Endemic syphilis is an acute or chronic infection caused by T pallidum subspecies endemicum. It has been reported in a number of countries, particularly in the eastern Mediterranean area, often with local names: bejel in Syria, Saudi Arabia, and Iraq, and dichuchwa, njovera, and siti in Africa. It also occurs in Southeast Asia. The local forms have distinctive features. Moist ulcerated lesions of the skin or oral or nasopharyngeal mucosa are the most common manifestations. Generalized lymphadenopathy and secondary and tertiary bone and skin lesions are also common. Deep leg pain points to periostitis or osteomyelitis. In the late stages of disease, destructive gummatous lesions similar to those seen in yaws can develop, resulting in loss of cartilage and saber shin deformity. Cardiovascular and CNS involvement are rare. See above for therapy.
et al. The endemic treponematoses. Clin Microbiol Rev. 2014 Jan;27(1):89–115.
M. Advances in the treatment of yaws. Trop Med Infect Dis. 2018 Aug 29;3(3):E92.