Overview

What is bejel?

Bejel, also known as endemic syphilis, is an infectious disease. Bejel is very common in parts of the world that have a dry and hot climate, particularly countries in the Eastern Mediterranean. Bejel is commonly transmitted from one individual to another via non-sexual skin contact or using the same utensils and dishware. Bejel causes lesions (damaged tissue) of the skin and bone, which begins in the mouth. There are different stages of the infection, and the infection can progress to a severe condition.¹ 

What causes bejel?

Bejel is caused by an infectious bacterium known as treponema. Treponema pallidum endemicum is a spiral shaped bacterium. Treponema pallidum endemicum belongs to the same family of bacteria as the bacterium that causes syphilis, yaws and pinta.

Where is bejel infection commonly seen around the world?

Bejel is commonly seen in countries that are hot and dry, especially the Sahel region in western Africa. Bejel infection is also common in the Arabian Peninsula and parts of Zimbabwe and Botswana.¹

Pathophysiology of bejel

Non-venereal transmission

Bejel is spread by having direct skin to skin or mouth to mouth contact with someone who has been infected by bejel, or via in-direct contact, such as sharing communal cooking or drinking utensils.²

Stages of disease: primary, secondary, tertiary

Primary stage

The first stage of bejel typically begins in childhood and is identified by a painless, small ulcer or patch in either the inside of the child’s mouth or the nasopharynx.³

Secondary stage

The secondary stage involves the transition from painless ulcers to a mucosal patch on the inside of the child’s mouth. Mucosal patches form when the child’s mucosal membranes (structures that line soft wet tissue in the mouth)break down. This gives rise to mucosal patches, which are described as being raised areas of tender tissue, which can have ulcers, and appear as a white or grey colour. The primary stage of bejel is also characterised by the appearance of raised lesions (areas of damaged tissue) found on both the limbs and the trunk of the body. The secondary stage is characterised by periostitis (inflammation) of the bones in your legs.^4,5,6

Tertiary stage

The tertiary stage of bejel is characterised by the appearance of gummas on the nose and the soft palate (the soft palate is a muscular part of your mouth, located at the back of the roof of your mouth). A gumma is a non-cancerous gummy tumour. Despite this tumour being non-cancerous, it can be highly destructive to your body. As the tumour develops, the central part of the gumma will start to soften and ulcerate, releasing a vicious gum-textured pus.^6,7

Skeletal manifestations in bejel

Primary stage

The initial lesion in bejel, which usually appears as a painless ulcer in the mouth, typically goes undetected. Particularly in the primary stage, the lack of other symptoms of the bejel infection, such as skeletal manifestations, can make it difficult to identify.⁸

Secondary stage

In the secondary stage, both periostitis and osteitis will begin to affect the bones in both your lower and upper limbs, for example, the tibia and fibula in your legs and the ulna and radius in your forearm. The extent of bone damage is not limited to these bones; the proximal phalanges (the bones that make up the digits in both your hands and feet) can also become damaged. Damage to these bones, due to periostitis and osteitis, can result in bone pain and swelling of the digits in your hands and feet.³

For you to see exactly which bones are affected in the hand and what is meant by ‘proximal phalanges, ’ the below image highlights the proximal phalanges in red. These are the bones that would begin to be affected by bejel in the secondary stage.

Image from Wikimedia Commons; this image can be found at the following link: 

https://commons.wikimedia.org/wiki/Category:Proximal_phalanges_of_the_hand#/media/File:Proximal_phalanges_of_the_hand_(left_hand)_01_palmar_view.png

The location of the ulna, radius, tibia and fibula is also shown in an image below to help you see where the bones affected by bejel are located in your body.

Image from Wikimedia Commons, this image can be found at the following link: https://upload.wikimedia.org/wikipedia/commons/8/83/Long_bones_-_anterior_view_-_with_legend.png

What is periostitis and osteitis?

Beginning with periostitis, periostitis is inflammation of the periosteum, which can be caused not only by bejel but also by other infections and trauma. Now, the periosteum is not a particular bone located in your body; it is the outer coating of your bones, acting as a sheath. The periosteum provides your bones with nutrient-rich blood and nerves. This may have you asking why your bones need a nutrient-rich blood supply and nerve innervation. Well, bones are like all other parts of our body; they grow, and they can be damaged, requiring healing, which blood and nerve innervation help to facilitate. ^9,10

Periostitis causes new bone formation, thickening parts of your bones, particularly around the distal parts of your ulna, radius, fibula and tibia. It is important to note that periostitis affecting your tibia may also be referred to as shin splints.

How else does periostitis affect me?

Periostitis can cause an aching pain, and you may experience swelling around the affected bones. Bones affected by periostitis may also be tender to touch. There may also be pus formation around the affected bones, and you may find it difficult to put weight on the limbs where the affected bones are located.

Moving on from periostitis, we will now look at osteitis. Similar to periostitis, osteitis results in inflammation of the bone. Unlike periostitis, the inflammation caused by osteitis is not limited to the periosteum (outer sheath/membrane of your bones). Osteitis can result in your bones starting to remodel themselves.¹⁴

Tertiary stage

Gummatous lesions

Gummatous lesions, also known as gummas (gummy non-cancerous tumours), are highly destructive tumours which start to develop in both the skin and the bone in the later stages of bejel infection.

Gummas can affect the following:¹⁵

• Nasopahrynx
• Larynx
• Skin
• Bone
• Palate
• Nasal septum

Nasal bones and facial features

Destructive gummas can occur in your nasal bones, causing your nasal bridge to collapse and your nasal septum to be destroyed. Destructive lesions and gummas in both the palate and the nasal septum can make it difficult for you to swallow and eat and can make it difficult for you to articulate your words.^15,16

The damage may not be restricted to your nasal bones, Gummas may begin to destroy your lips and your soft palate, resulting in facial deformities.¹⁷

Sabre tibia (tibial bowing)

Sabre tibia is the result of chronic osteitis in the latest stages of bejel infection. In the sabre tibia, the tibia curved forward and appears to be bowing.^3,18

Clinical presentation

Diagnosing bejel

Medical history and geographical history

Typically, diagnosis of bejel involves taking a geographic history of the patient, which involves looking at which countries the patient has been to, and if bejel infection is common in these countries, and has resulted in an endemic.

Microscopy

Following from this, a sample from the lesions that have been caused by the infection will be taken for a darkfield examination. The bacteria that is responsible for the infection will be visualised under a microscope, and if it is a spiral-shaped treponema, this will highlight that this bacterium is responsible for the infection.

Serological tests

Samples of the fluid surrounding the lesions will also be taken, and an FTA-ABS (fluorescent treponemal antibody-absorption) test will be conducted. This test will detect if there are any antibodies (proteins produced by your immune system that have a specific shape, complementary to the proteins on a foreign cell, such as the Treponema pallidum endemicum bacteria) specific to Treponema pallidum endemicum. If they are present, this will confirm a bejel infection.

Additionally, a Venereal Disease Research Laboratory (VDRL) test will be conducted, which will detect nonspecific antibodies. If these antibodies are present, and the test is positive, this will indicate a bejel infection.^3,19 

Treatment

Antibiotic therapy

Typically, bejel is treated with antibiotic therapy, and you will be given a drug benzathine penicillin G. If you have a penicillin allergy, you may be given an alternative antibiotic to treat the infection, such as doxycycline or tetracycline.

Physiotherapy

If bejel has progressed to a secondary or tertiary stage before treatment, you may need treatment for periostitis and osteitis. Treatment for this is typically a course of physiotherapy and targeted exercises.

Summary

• Bejel, also known as endemic syphilis, causes damage to the skin and bones, with lesions (damaged tissue) beginning in the mouth
• Bejel is transmitted via direct skin to skin or mouth to mouth contact
• Bejel can also be transmitted via indirect contact, for example using the same cooking utensils
• Bejel is a bacterial infection caused by the bacterial species Treponema pallidium endemicum
• Bejel is common in countries with a hot and dry climate
• Bejel progresses from an ulcer in the mouth (the primary stage) through to the secondary stage (where lesions in the mouth progress to mucosal patches, and there is inflammation of the bone) through to the tertiary stage (where non-cancerous gummy tumours develop in the skin and bone)
• Bones commonly affected by inflammation due to bejel infection, including your ulna, radius, tibia, femur, and bones in your nose