Nummular keratitis

A type of corneal inflammation

Nummular keratitis is a form of keratitis, which is an inflammation of the cornea, the clear, dome-shaped surface that covers the front of the eye. This condition is characterized by the presence of small, round, coin-shaped lesions on the cornea, which can lead to visual disturbances and discomfort.

Pathophysiology

Nummular keratitis is often associated with viral infections, particularly those caused by the herpes simplex virus and the varicella-zoster virus. The condition is thought to result from an immune-mediated response to viral antigens deposited in the corneal stroma. The lesions are typically located in the superficial layers of the cornea and consist of inflammatory cells and deposits.

Clinical Presentation

Patients with nummular keratitis typically present with symptoms such as:

• Blurred vision
• Eye pain
• Photophobia (sensitivity to light)
• Tearing
• Redness of the eye

The characteristic lesions can be observed during a slit-lamp examination, appearing as small, round, grayish-white opacities in the corneal epithelium.

Diagnosis

The diagnosis of nummular keratitis is primarily clinical, based on the appearance of the corneal lesions and the patient's history. A slit-lamp examination is essential for visualizing the characteristic nummular lesions. In some cases, additional tests such as corneal staining with fluorescein or viral cultures may be performed to confirm the underlying viral etiology.

Treatment

Nummular keratitis lesions on the cornea

The treatment of nummular keratitis involves addressing the underlying cause and managing the inflammatory response. Common treatment options include:

• Topical antiviral medications, such as acyclovir or ganciclovir, to target the viral infection.
• Topical corticosteroids to reduce inflammation and prevent scarring.
• Lubricating eye drops to alleviate discomfort and protect the corneal surface.

It is important to monitor patients closely during treatment to prevent complications such as corneal scarring or secondary bacterial infections.

Prognosis

With appropriate treatment, the prognosis for nummular keratitis is generally good. Most patients experience resolution of symptoms and improvement in vision. However, some individuals may develop residual corneal scarring, which can lead to permanent visual impairment.

Prevention

Preventive measures for nummular keratitis focus on reducing the risk of viral infections and managing underlying conditions that may predispose individuals to corneal inflammation. This includes:

• Practicing good hygiene to prevent the spread of viral infections.
• Using protective eyewear in environments that pose a risk of eye injury or infection.
• Managing systemic conditions, such as herpes simplex or herpes zoster, with appropriate antiviral therapy.

Related pages

• Keratitis
• Herpes simplex keratitis
• Corneal ulcer