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Chapter 35

Yaws; Endemic (Nonvenereal) and Congenital Syphilis

For many years it has been customary to consider nonvenereal syphilis and yaws as separate entities. Now the experts, differing among themselves, have raised doubts about the validity of this "separate disease" concept. There are many clinical similarities but also some obvious differences, which may be due in part to differing sociological and economic backgrounds as well as varying climates and other factors. The debate continues, and meanwhile, because of antibiotics, these treponemal diseases, which were once widely spread and devastating, seemed to be coming under control. Unfortunately, due to many factors, some changeable and others not, this is no longer the case and the infections are increasing again just when they were thought to have been almost eliminated. In the 1950s and 1960s, WHO and UNICEF claimed that 50 million people in 46 countries had been cured of yaws. A more recent estimate (1990) suggested that there were still over 2.5 million people with yaws and endemic syphilis, 75% of whom were children, and that there are a further 100 million at risk. Venereal syphilis (which is not specifically included in this chapter) is equally intransigent: in Russia alone it is said to have increased 15-fold, and in children the rate there is now 20 times higher than it was in 1991. It is doubtful whether accurate figures exist for the tropical world, but it has certainly not disappeared. Congenital syphilis (which is considered in this chapter) is definitely increasing.

It is often difficult, if not impossible, for the radiologist to differentiate between endemic syphilis and yaws. Despite the success of eradication campaigns, there will for years be the challenge of the differential diagnosis, both of the active diseases and their end results. The other major treponemal infection, pinta, has no radiological significance.


Endemic syphilis: Nonvenereal syphilis. Innocent syphilis. Bejel (Syria). Bosnian syphilis. Skerljero. Frenga (Bosnia). Bishel (Iraq). Belesh (Arabia). Dichuchwa (Botswana). Njovera (Zimbabwe). Siti (Gambia, Ghana). Fr: Syphilis non-venerienne. Vérole. Ger: Syphilis insontium. Endemische Syphilis. Sp: Sifilis. Mal gallico.

Yaws: Framboesia. Pian. Goundou (when the maxilla is affected). Gangosa. Rhinopharyngitis mutilans. Bouba. Parangi. Domaria Domaru. Domaru Khahu. Fr: Framboesia tropica (framboise). Pian. Ger: Himbeerkrankheit. Endemische Hautkrankheit der Tropen durch Treponema pertenue. Frambösie. Sp: Sifilis non venérea. Pian o frambesia.

Pinta: Mal de pinto. Carate (Colombia). Azul. Boussarole. Tina. Ger: Pinto Krankheit.


The treponematoses are an infection with any treponeme. There are two main groups of treponematoses: those which are nonvenereal and are transmitted mainly between children, and the others which are venereal and occur in adolescents and adults. The nonvenereal treponematoses can be subdivided according to the organism responsible:

- Endemic syphilis is caused by Treponema pallidum.
- Yaws is caused by T. pertenue.
- Pinta is caused by T. carateum.

All the treponemata are spirochetes and are morphologically, serologically, and in every other respect indistinguishable. They are motile, about 3-18 Ám long, and have from 8 to 20 corkscrew spirals. They are separated into three species on the basis of animal infections. Not all pathologists accept this separation; some regard T. pallidum as the only organism.

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Copyright: Palmer and Reeder