Bejel, Pinta, and Yaws

ByLarry M. Bush, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University;
Maria T. Vazquez-Pertejo, MD, FACP, Wellington Regional Medical Center
Reviewed/Revised Nov 2022
View Patient Education

Bejel, pinta, and yaws (endemic treponematoses) are chronic, tropical, nonvenereal spirochetal infections spread by body contact. Symptoms of bejel are mucous membrane and cutaneous lesions, followed by bone and skin gummas. Yaws causes periostitis and dermal lesions. Pinta lesions are confined to the dermis. Diagnosis is clinical and epidemiologic. Treatment is with azithromycin.

Spirochetes are distinguished by the helical shape of the bacteria. Pathogenic spirochetes include Treponema, Leptospira, and Borrelia. Both Treponema and Leptospira are too thin to be seen using brightfield microscopy but are clearly seen using darkfield or phase microscopy. Borrelia are thicker and can also be stained and seen using brightfield microscopy.

The causative agents of bejel, pinta, and yaws are

  • Bejel: Treponema pallidum subspecies endemicum

  • Yaws: T. pallidum subspecies pertenue

  • Pinta: Treponema carateum

These Treponema species are morphologically and serologically indistinguishable from the agent of syphilis, T. pallidum subspecies pallidum. As in syphilis, the typical course is an initial mucocutaneous lesion followed by diffuse secondary lesions, a latent period, and late destructive disease.

Transmission is by close skin contact—sexual or not—primarily between children living in conditions of poor hygiene.

Bejel (endemic syphilis) occurs mainly in hot, dry regions of the eastern Mediterranean and Saharan West Africa. Transmission results from mouth-to-mouth contact or sharing eating and drinking utensils.

Yaws (frambesia) is the most prevalent of the endemic treponematoses and occurs in humid equatorial countries. Transmission requires direct skin contact and is favored by skin trauma.

Pinta, which is more limited in geographical distribution, occurs among the natives of Mexico, Central America, and South America and is not very contagious. Transmission probably requires contact with broken skin.

Unlike T. pallidum subspecies pallidum, other human treponemal subspecies are not transmitted via blood or transplacentally.

Symptoms and Signs of Bejel, Pinta, and Yaws

Bejel begins in childhood as a mucous patch (usually on the buccal mucosa), which may go unnoticed, or as stomatitis at the angles of the lips. These painless lesions may resolve spontaneously but are usually followed by papulosquamous and erosive papular lesions of the trunk and extremities that are similar to yaws. Periostitis of the leg bones is common. Later, gummatous lesions of the nose and soft palate develop.

Yaws, after an incubation period of several weeks, begins at the site of inoculation as a red papule that enlarges, erodes, and ulcerates (primary yaws). The surface resembles a strawberry, and the exudate is rich in spirochetes. Local lymph nodes may be enlarged and tender. The lesion heals but is followed after months to a year by successive generalized eruptions that resemble the primary lesion (secondary yaws). These lesions often develop in moist areas of the axillae, skinfolds, and mucosal surfaces; they heal slowly and may recur. Keratotic lesions may develop on the palms and soles, causing painful ulcerations (crab yaws). Five to 10 years later, destructive lesions (tertiary yaws) may develop; they include the following:

  • Periostitis (particularly of the tibia)

  • Proliferative exostoses of the nasal portion of the maxillary bone (goundou)

  • Juxta-articular nodules

  • Gummatous skin lesions

  • Ultimately, mutilating facial ulcers, particularly around the nose (gangosa)

Stages of Yaws
Yaws—Primary
Yaws—Primary

Primary yaws manifests as a large yellow papule or papillomata at the site of inoculation. Papules are highly infectious (top). This image shows the buttocks of a girl with primary yaws. Primary yaws lesions may also develop a crusted surface (bottom).

... read more

Top image courtesy of Dr. Peter Perine via the Public Health Image Library of the Centers for Disease Control and Prevention. Bottom image courtesy of K McLennon, Tulane University Medical School, via the Public Health Image Library of the Centers for Disease Control and Prevention.

Yaws—Secondary
Yaws—Secondary

After the lesion of primary yaws heals, a generalized eruption of soft granulomata on the face, extremities (top), or buttocks occurs. Another feature of secondary yaws is soft, keratotic, tumor-like masses that develop on the soles of the feet (bottom). The masses force patients to walk on the sides of their feet, giving rise to the nickname crab yaws.

... read more

Top image courtesy of Dr. Peter Perine via the Public Health Image Library of the Centers for Disease Control and Prevention. Bottom image courtesy of Dr. Susan Lindsley via the Public Health Image Library of the Centers for Disease Control and Prevention.

Yaws—Tertiary
Yaws—Tertiary

About 10% of untreated patients develop tertiary yaws, which causes disfiguring bone and soft-tissue lesions.

Image courtesy of Dr. Peter Perine via the Public Health Image Library of the Centers for Disease Control and Prevention.

Pinta lesions are confined to the dermis. They begin at the inoculation site as a small papule that enlarges and becomes hyperkeratotic; they develop mainly on the extremities, face, and neck. After 3 to 9 months, further thickened and flat lesions (pintids) appear all over the body and over bony prominences. Still later, some lesions become slate blue or depigmented, resembling vitiligo. Pinta lesions typically persist if not treated.

Diagnosis of Bejel, Pinta, and Yaws

  • Clinical evaluation

Diagnosis of endemic treponematoses is based on the typical appearance of lesions in people from endemic areas.

Both nontreponemal and treponemal serologic tests for syphilis (the Venereal Disease Research Laboratory [VDRL], rapid plasma reagin [RPR], and fluorescent treponemal antibody absorption tests [FTA-ABS]) are positive; thus, differentiation from venereal syphilis is clinical. Early lesions are often darkfield-positive for spirochetes and are indistinguishable from T. pallidum subspecies pallidum.

Treatment of Bejel, Pinta, and Yaws

  • Azithromycin

azithromycin is a single dose of penicillin benzathine 1.2 million units IM for patients 10 years of age and older and 600,000 units IM for children younger than 10 years of age (1

Public health control includes active case finding and treatment of family and close contacts with penicillin benzathine or doxycycline to prevent infection from developing.

Treatment reference

  1. 1. Giacani L, Lukehart SA: The endemic treponematoses. Clin Microbiol Rev 27(1):89–115, 2014. doi: 10.1128/CMR.00070-13

Key Points

  • The Treponema species that cause bejel, pinta, and yaws are morphologically and serologically indistinguishable from the agent of syphilis, T. pallidum subspecies pallidum.

  • Disease is spread by close body contact, typically between children living in conditions of poor hygiene.

  • As in syphilis, the typical course is an initial mucocutaneous lesion, followed by diffuse secondary lesions, a latent period, and late destructive disease.

  • Serologic tests for syphilis (including fluorescent treponemal antibody absorption tests) are positive; thus, differentiation from venereal syphilis is clinical.

  • Treat close contacts with antibiotics.

Drugs Mentioned In This Article

quizzes_lightbulb_red
Test your KnowledgeTake a Quiz!
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID
Download the free Merck Manual App iOS ANDROID