Vogt-Koyanagi-Harada (VKH) Disease
Disease Overview
Vogt-Koyanagi-Harada disease is a rare disorder of unknown origin that affects many body systems, including as the eyes, ears, skin, and the covering of the brain and spinal cord (the meninges). The most noticeable symptom is a rapid loss of vision. There may also be neurological signs such as severe headache, vertigo, nausea, and drowsiness. Loss of hearing, and loss of hair (alopecia) and skin color may occur along, with whitening (loss of pigmentation) of the hair and eyelashes (poliosis).
Signs & Symptoms
Vogt-Koyanagi-Harada disease is initially characterized by headaches, very deep pain in the eyes, dizziness (vertigo), and nausea. These symptoms are usually followed in a few weeks by eye inflammation (uveitis) and blurring of vision. This may occur in both eyes at the same time or in one eye first and, a few days later, in the other. The retina may detach and hearing loss may become apparent.
The chronic stage follows in a few weeks. This stage is characterized by changes in the eyes and skin. The changes in the eyes may include loss of color in the layer of the eye filled with blood vessels that nourish the retina (choroid), as well as the development of small yellow nodules in parts of the retina. Skin changes may include the development of smooth, white patches in the skin caused by the loss of pigment-producing cells (vitiligo). These white patches are usually distributed over the head, eyelids and torso. The chronic stage can last for several months to several years.
In many individuals, treatment improves sight and hearing. However, there may be some permanent problems, including vision and hearing deficits, and hair loss with associated loss of color of the hair, eyelashes, and skin. Lasting visual effects may include the development of secondary glaucoma and cataracts.
Causes
The exact cause of Vogt-Koyanagi-Harada disease is unknown. It is thought by researchers to be an immune response to the human leukocyte antigen (HLA). These are genetic markers located on chromosome 6 that react specifically with a particular antibody. This genetic defect may predispose persons who carry this antigen to develop Vogt-Koyanagi-Harada disease.
Autoimmune disorders are caused when the body’s natural defenses (antibodies, lymphocytes, etc.) against invading organisms suddenly begin to attack perfectly healthy tissue.
Some researchers also think that there may be a genetic predisposition for the disease since it has occurred in a brother and sister and in a set of twins. A genetic predisposition means that a person may carry a gene for a disease but it may not be expressed unless something in the environment triggers the disease.
Disorders with Similar Symptoms
Symptoms of the following disorders can be similar to those of Vogt-Koyanagi-Harada disease or may occur in conjunction with Vogt-Koyanagi-Harada disease.
Alopecia is unpredictable hair loss due to an unknown cause. Regrowth of hair may or may not occur. Hair loss is usually confined to the head and face, although the entire body may be involved. (For more information on this disorder, choose “Alopecia” as your search term in the Rare Disease Database.)
Vitiligo is characterized by spots on the skin with decreased pigmentation. These areas are usually sharply demarcated with increased coloring (hyperpigmentation) on the borders, and are often symmetrical in shape. The face, neck, hands, abdomen, and thighs are most often affected. The hair and skin in the area are usually white. The white areas are prone to sunburn and should be protected from sunlight. (For more information on this disorder, choose “Vitiligo” as your search term in the Rare Disease Database.)
Glaucoma may occur as a secondary characteristic of VKH disease. It is characterized by increased pressure within the eye. If left untreated the increased pressure may affect the lens and optic nerve of the eye, resulting in eventual blindness. Some symptoms for people to be aware of are: blurred vision, rainbow colored halos around lights, and loss of side vision resulting in “tunnel vision.”
Diagnosis
The diagnostic criteria for VKH disease includes inflammation of both eyes, no evidence of another ocular disease causing the inflammation, and no history of trauma or ocular surgery. An international group of experts has established three categories of disease:
a. Complete VKH disease: diffuse choroiditis involving both eyes that may include serous retinal detachments. Inflammation of the iris and ciliary body may develop in some patients. The complete form of the disease includes neurologic signs such as ringing in the ears (tinnitus), neck stiffness, and/or cells in the cerebrospinal fluid (pleocytosis) as well as dermatological signs such as white patches on the arms or torso, sudden loss of hair (alopecia), or loss of color of the hair, eyelashes or eyelids (poliosis)
b. Incomplete VKH disease: similar eye disease as patients with complete VKH disease but do not have both neurologic and dermatological signs. Patients must have either the neurologic manifestations or dermatological signs.
c. Probable VKH disease: similar eye disease as patients with complete VKH disease but without neurologic and dermatological signs.
Treatment
Standard treatment of Vogt-Koyanagi-Harada disease is the use of high-dose systemic steroid drugs initially and often followed by immunosuppressive therapy. Testing used by an ophthalmologist or neurologist to determine if this disease is present include a spinal tap, x-ray of the blood vessels after the injection of dye (angiography), and ultrasound. Other treatment is symptomatic and supportive.
TYPE OF DOCTOR AND DEPARTMENT: RETINA SPECIALIST CAN DIAGNOSE THIS DISEASE.
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