Multifocal Choroidopathy Syndrome - Symptoms, Diagnosis, and Treatment

Introduction

Multifocal choroiditis (MFC), earlier known as punctate choroidopathy syndrome, is a chronic granulomatous inflammatory condition. It is accompanied by uveitis and multiple retinal-choroidal lesions. It is a chronic condition with recurrent and worsening outlook even after treatment.

What Is the Main Cause of MFC?

The exact cause of MFC is not known. Several infectious and inflammatory conditions are hypothesized to stimulate an immune response in the host.

Based on the causative factors, MFC is divided into,

• Infectious MFC is related to bacterial and fungal ocular diseases.

• Noninfectious MFC is linked to chronic inflammatory conditions like granulomatous inflammation.

• Idiopathic MFC does not have any cause. It develops spontaneously.

How Is MFC Developed?

• The principal mechanism involved in MFC development comprises the stimulation of the immune response by the causative agents (inflammation, infection, or idiopathic).

• The initiation of the immune response damages the integrity of the innermost layer of the eye, Broch's membrane.

• The disintegration of the ocular structures results in inflammation of the choroid and retina. It is followed by choroidal neovascularization in the majority of cases.

What Is the Classification of MFC?

Classification of multifocal choroidopathy syndrome:

Clinical Features:

• Lesions: A collection of several small, yellow-white spots in the area of the retina’s outer layer, RPE and choroid.

• Location: Usually involves the posterior pole, which is the macula, and also the mid-peripheral area of the retina.

• Bilateral Involvement: Typically, it is bilateral; however, the distribution of the symptoms may vary from mild to severe.

Associated Symptoms:

• Visual Symptoms: Visual disturbances include hazy vision, scotoma, and photopsia.

• Anterior Uveitis: Occasionally accompanied by mild anterior uveitis.

Diagnostic Imaging:

• Fundus Fluorescein Angiography (FFA): Demonstrates initial decrease and later increase in the intensity of the lesions’ fluorescence.

• Indocyanine Green Angiography (ICGA): This has given it hypocyanescent spots.

• Optical Coherence Tomography (OCT): Able to detect disruptions of the RPE and choriocapillaris.

Differential Diagnosis:

• Other White Dot Syndromes:

  • Acute Posterior Multifocal Placoid Pigment Epitheliopathy (APMPPE).

  • Multiple Evanescent White Dot Syndrome (MEWDS).

  • Birdshot chorioretinopathy.

  • Serpiginous choroiditis.

• Infectious Causes: For example, tuberculosis, syphilis, and toxoplasmosis are some of the diseases that can be transmitted through sexual intercourse.

• Autoimmune Conditions: Sarcoidosis, Behcet’s disease.

Etiology: The specific cause is not known, but it is thought to be an autoimmune disease.

Treatment:

• Corticosteroids: Oral or periocular corticosteroids to decrease inflammation.

• Immunomodulatory Therapy: Where the disease is long-standing or tends to recur.

• Anti-VEGF Therapy: For related choroidal neovascularization.

What Are the Clinical Presentations of MFC?

• White females and young adults are more prone to get MFC. It has a spontaneous and bilateral presentation.

• The most common site involved includes the retinal and subretinal spaces, sometimes extending to the anterior chamber.

• Patients also present with Schlaegel lines (chorioretinal streaks) in the periphery.

• The formation of choroid vascular membrane in a subset of the population is noted.

• Inflammation of all the layers of the eye with the presence of multiple yellow or gray spots scattered in the retinal and choroidal region.

Other signs and symptoms include:

• Scotoma is the blind spot in the eye blocking vision.

• Blurred vision.

• Floaters.

• Photophobia is sensitivity to light.

• There is the presence of apparent flashes in the eye.

• A distorted vision where a straight line appears curved.

• Vision loss.

How Is MFC Diagnosed?

The diagnosis of MFC is primarily based on clinical examination and visual field tests. Imaging and laboratory tests are adjuncts performed to further diagnose other diseases.

• Eye field tests and slit-lamp techniques are used for the physical examination. The main feature seen is the presence of scotoma and yellow to gray spots scattered over the retina. In the acute phase, there is optic nerve swelling, hyperemia, subretinal fluid, and choroid neovascularization.

• Color fundus photography helps differentiate active lesions (yellow) and inactive lesions (gray) seen in the retina.

• Fluorescein fundus angiography aids in determining the active lesions and choroid neovascularization.

• Optical coherence tomography (OCT) shows swelling of the retinal pigment epithelium.

• Indocyanine green angiography and fundus autofluorescence help investigate the acute inflammatory lesions based on the lesion's fluorescence.

• Electroretinograms investigate the electrical activity of the retina. It varies in MFC patients.

• Various pathological tests, including serological, tuberculin, interferon tests, microbial cultures, and chest X-rays, are performed to look for other diseases.

What Are the Conditions Mimicking MFC?

Due to the multifactorial risk factors associated with MFC, various ocular conditions must be ruled out before an accurate diagnosis of MFC can be made.

• Infectious Diseases:

  • Toxoplasmosis.

  • Tuberculosis.

• Inflammatory:

  • Sarcoidosis.

  • Punctate inner choroidopathy.

• Malignant:

  • Lymphoma.

How Is MFC Managed?

The centerpiece of MFC treatment planning is managing the symptoms and preventing further deterioration of the condition. MFC has no permanent cure.

• Oral and topical steroids are the drugs of choice for treating MFC due to their immunosuppressive and anti-inflammatory action. Patients receiving corticosteroids should be monitored for intraocular pressure and cataract development.

• Immunomodulators like Cyclosporin, biologics and T-cell inhibitors manage patients who are unresponsive to steroids.

• Laser therapy is recommended in severe cases.

• Anti-inflammatory and anti-vascular endothelial growth factors are essential in treating acute lesions accompanied by choroid neovascularizations.

What Are the Complications Related to MFC?

MFC is a chronic recurrent condition that may progress into,

• Subretinal fibrosis is the formation of fibrous bands underneath the retina.

• Macular and choroidal neovascularization.

• Cystoid macular edema is a condition described by multiple cyst-like areas in the macula and retina.

• Glaucoma is linked to optic nerve damage and blindness.

• Optic nerve atrophy damages the optic nerve affecting central, peripheral, and color vision.

Discovery of a New Variant?

A new subvariant of MFC is "idiopathic multifocal choroiditis with atrophy." It involves the posterior pole and fungus region. It is characterized by the more diffuse and multizonal atrophy of the choroidal and retinal structures. It shows the presence of widespread chorioretinal lesions, sparing the fovea region till the advanced stage. MFC with atrophy occurs in bouts of inflammation and further disease progression. Spectral-domain OCT (SD-OCT) and fundus autofluorescence demonstrate the diffuse disruption of the retinal pigment epithelium (RPE). It has a strong genetic association, unlike the classic MFC.

What Is the Prognosis of MFC?

Throughout the disease, patients suffering from MFC maintain visual equity if they do not have other comorbidities. Other complications accompanying MFC impair vision and gravely reduce the prognosis of the disease.

Conclusion

MFC is a chronic inflammatory disease of unknown etiology. Palliative care helps in reducing the symptoms and severity. Long-term follow-up is essential to prevent flareup and complications.