Can Behcet's disease cause mucosal ulcers and eye inflammation? The hazards are more than that!

Author: Guo Yanqiu, deputy chief physician, Beijing Anzhen Hospital, Capital Medical University

Reviewer: Pan Lili, Chief Physician, Beijing Anzhen Hospital, Capital Medical University

Behcet's disease is a systemic immune system disease, a type of vasculitis that can affect large, medium and small arteries and veins throughout the body. It is mainly manifested by recurrent oral ulcers, genital ulcers, uveitis and skin lesions.

In 1937, Turkish dermatologist Behcet first systematically described this type of disease and proposed the triad of recurrent oral ulcers, genital ulcers and eye inflammation. After that, people gradually began to pay attention to this disease, and in order to commemorate this doctor, the disease was named Behcet's syndrome, or Behcet's disease for short.

Behçet's disease belongs to the category of vasculitis. The range of blood vessels involved is relatively wide and the clinical manifestations are also diverse.

The mucosa has many blood vessels to supply blood. Mucosal ulcers are actually a manifestation of small vessel vasculitis, including recurrent oral ulcers, female vulvar ulcers, and male genital ulcers. Oral ulcers are often the first symptom, manifested as multiple ulcers on the buccal mucosa, tongue edge, lips, soft palate, etc., accompanied by pain. The surface may be covered with a white film. Most of them are superficial ulcers, which can disappear on their own in 7-14 days, but they will recur.

Figure 1 Original copyright image, no permission to reprint

Vulvar ulcers are similar in shape to oral ulcers, but they occur less frequently and in fewer numbers. In female patients, they often appear on the labia majora and minora and in the vagina, while in male patients, they are more common on the scrotum and penis, and can also appear near the anus.

Eye inflammation caused by Behcet's disease is actually a manifestation of vasculitis. The uvea is the middle layer of the eyeball wall, rich in blood vessels and pigments. It is divided into the anterior uvea and the posterior uvea. The anterior uvea includes the iris and ciliary body, and the posterior uvea is the choroid. Behcet's disease mainly affects the anterior uvea, which will affect the iris and ciliary body, and cause hypopyon.

The skin lesions of Behcet's disease are mainly manifested as erythema nodosum, which usually occurs in the area below the knees, is symmetrically distributed, and is coin-sized, accompanied by tenderness. It will gradually expand but can disappear on its own. In addition, it can also manifest as pseudofolliculitis, acneiform folliculitis, papulopustular rash, and superficial thrombophlebitis.

Figure 2 Original copyright image, no permission to reprint

Behcet's disease is a vasculitis disease. Neutrophils, lymphocytes and monocytes can be seen infiltrating the blood vessel wall, the perivascular area and nearby tissues. Some necrotic structures will form on the vessel wall. These necrotic structures will destroy the vessel wall structure, leading to vascular wall necrosis and vascular embolism. Lesions of large, medium and small arteries and veins in various parts of the body can occur. If it affects the veins, it mainly manifests as venous thrombosis; if it affects the arteries, it mainly manifests as aneurysms, and it may also cause arterial stenosis.

Behcet's disease affects the nervous system, which may cause impaired consciousness, mental abnormalities, epilepsy, sensory disorders, etc.; affects the cardiovascular system, which may lead to arteriovenous obstruction, aneurysm and lumen stenosis; affects the digestive tract, which may lead to digestive ulcers and perforations; affects the lungs, which may lead to complications such as pulmonary artery aneurysm, bronchial fistula or pulmonary infarction; affects the joints, which may manifest as repeated swelling and pain in a single or a few joints, which are mostly transient, and are most common in the knee joints. Some patients may develop sacroiliitis.

The cause of Behcet's disease is unknown. It is closely related to infection, immunity, genetics, and environmental factors. It is currently incurable and has a long course, which can last for decades. Various symptoms may recur. Those with severe eye lesions are at risk of blindness and may die from severe visceral or nerve damage. The treatment of Behcet's disease mainly uses large doses of glucocorticoids and immunosuppressants. Anti-inflammatory treatment is used to inhibit inflammatory responses, prevent damage to important organs, and delay disease progression. Effective control of the primary disease can relieve overall inflammation. Although these drugs cannot fundamentally solve the problem, they can slow the progression of organ damage and improve prognosis.