bubble_chart Overview

Idiopathic uveomeningitis, also known as pigment membrane encephalitis, is a syndrome initially reported by Vogt and Koyanagi (Koyanagi) characterized primarily by anterior uveitis, accompanied by poliosis, alopecia, vitiligo, and hearing impairment. Later, Harada (Harada) described a similar condition presenting with bilateral exudative uveitis predominantly affecting the posterior segment. Hence, it is also referred to as Vogt-Koyanagi-Harada syndrome (VKH).

bubble_chart Etiology

The cause of the disease is unknown, with the following two hypotheses:

1. Koyanagi believes that the disease is caused by a virus, but the actual results were negative.

2. It is currently widely considered to be an autoimmune disease. It is likely that disease-causing factors such as viruses first act on a susceptible body, causing nonspecific prodromal symptoms. On the other hand, these factors induce antigenic changes in pigment cells, triggering an autoimmune reaction. This leads to various clinical manifestations of systemic pigment cell damage.

bubble_chart Clinical Manifestations

1. It manifests as headache, dizziness, nausea, vomiting, neck stiffness, and other meningeal irritation symptoms. In the Vogt-Koyanagi type, 50% of patients exhibit meningeal irritation symptoms; in the Harada type, this can be as high as 90%. Shortly after these symptoms appear, uveitis develops.

2. Ocular symptoms emerge 3–5 days after the prodromal symptoms, including eye pain, redness, and decreased vision. The ocular manifestations are as follows:

(1) **Vogt-Koyanagi type**: Primarily characterized by exudative iridocyclitis, often accompanied by diffuse choroidoretinitis. The anterior chamber shows significant exudation, obscuring the pupillary area, with severe and extensive posterior synechiae of the iris. The fundus becomes indistinct, leading to various complications and sequelae.

(2) **Harada type**: Sudden bilateral vision loss, with prominent posterior segment changes. The optic disc and macula exhibit marked edema, gradually progressing to pan-fundus edema, followed by retinal detachment. Concurrently, diffuse atrophy of the pigment epithelium and vitreous opacities occur. Inflammation may extend anteriorly but is milder than in the Vogt-Koyanagi type.

3. **Auditory and dermatological phase**: Weeks or months after the onset of ocular symptoms, tinnitus, hearing impairment, hair whitening, alopecia, and vitiligo may appear. These changes reflect labyrinthine and central nervous system involvement, typically symmetrical.

4. **Convalescent stage**: In cases of recurrent episodes, the condition progressively worsens, leading to iris atrophy, pupillary membrane occlusion, complicated cataract, secondary glaucoma, or even phthisis bulbi. In the Harada type, subretinal fluid resolves, the retina reattaches, and significant retinal pigment loss results in a "sunset glow" fundus (also called "sunset red").

bubble_chart Diagnosis

1. Clinical symptoms: Diffuse pigment membrane inflammation in both eyes. The anterior segment develops into granulomatous inflammation, while the posterior segment shows localized retinal detachment at the optic disc and macula, as well as an advanced-stage "sunset-like" fundus.

2. Accompanied by changes in hair, skin, and other areas.

3. Often requires differentiation from conditions such as panuveitis and Behçet's disease. {|102|}

bubble_chart Treatment Measures

1. Fully and persistently dilate the pupils. Maintain pupil activity to prevent posterior synechia of the iris.

2. Apply corticosteroids locally and systemically, such as dexamethasone eye drops, subconjunctival and periocular injections. Administer dexamethasone or hydrocortisone orally or intravenously. Use high doses early and reduce quickly, then taper slowly. Avoid rapid reduction within 1 month. Maintain treatment for 3–6 months. Also supplement potassium.

3. Administer high-dose vitamins systemically.

4. Adjunctive medications: Systemic use of ATP, coenzyme A, inosine, etc.

5. For severe cases, consider trying immunosuppressants such as cyclophosphamide.

6. Chinese medicinals: clearing heat and removing toxin, promoting diuresis and improving vision Chinese medicinals.