R R

What Is Nummular Keratitis?

Nummular keratitis is a form of corneal inflammation marked by small, round, subepithelial opacities that resemble tiny coins. It most often develops after epidemic keratoconjunctivitis caused by adenovirus. As the acute redness and discharge settle, these nummular lesions appear in the anterior stroma or just beneath the epithelium. They can persist for weeks or months and sometimes reduce vision or cause glare. The condition reflects an immune mediated response rather than active viral replication in the cornea.

Link to This Resource Page

Provide a valuable resource to your clients or customers by linking to this resource page. Just place the following link on your website.

To display this...

What Is Nummular Keratitis?

Nummular keratitis is a form of corneal inflammation marked by small, round, subepithelial opacities that resemble tiny coins. It most often develops after epidemic keratoconjunctivitis caused by adenovirus. As the acute redness and discharge settle, these nummular lesions appear in the anterior stroma or just beneath the epithelium. They can persist for weeks or months and sometimes reduce vision or cause glare. The condition reflects an immune mediated response rather than active viral replication in the cornea.

read more about nummular keratitis ...

Copy this HTML:

Copy HTML Copied!

Causes and Pathogenesis

Nummular keratitis is classically linked to adenoviral infection of the conjunctiva and cornea. After the initial epithelial infection, viral antigens and host immune complexes deposit in the anterior stroma. This triggers focal inflammatory reactions that form the characteristic subepithelial spots. Similar patterns can occasionally occur with other infections or inflammatory diseases, but adenovirus is by far the most common trigger. Contact with contaminated hands, instruments, or surfaces often spreads the original conjunctivitis in community or clinic settings.

Symptoms and Corneal Findings

Patients often complain of blurred vision, light sensitivity, and a sensation of looking through haze after the red eye phase improves. On slit lamp examination, multiple small, gray white, round lesions are seen in the central and paracentral cornea. The overlying epithelium is typically intact, although mild punctate staining can be present. The number and size of lesions vary, and both eyes can be affected, often with asymmetric involvement. Tear film instability and mild anterior chamber reaction are sometimes noted.

Diagnosis and Differential Diagnosis

Diagnosis relies on the history of recent adenoviral keratoconjunctivitis combined with the typical appearance of nummular lesions. The clinician distinguishes these spots from active infectious infiltrates, Thygeson superficial punctate keratitis, and other subepithelial opacities. Lack of significant pain and the presence of intact epithelium support a postinfectious immune pattern. Laboratory testing is rarely needed once the clinical course is clear. Photographs and serial examinations document gradual resolution or persistence.

Treatment and Prognosis

Treatment aims to reduce symptoms and control inflammation while minimizing side effects. Lubricating drops and cool compresses improve comfort. Topical corticosteroids are often used in low doses and tapered slowly to reduce haze, but they can prolong viral shedding if started too early in the acute phase. In some cases, topical cyclosporine is considered as a steroid sparing option. Most lesions fade over time, but a few can leave faint scars or mild irregularity that affects contrast sensitivity.

FAQs About Nummular Keratitis

Is nummular keratitis still contagious?

The nummular stage reflects an immune response, and contagious viral shedding is usually much lower than during the initial conjunctivitis.

Will the spots on my cornea go away completely?

Many patients see gradual clearing, although some retain faint residual opacities that have little impact on vision.

Why did my vision get worse after the red eye seemed better?

As the surface heals, subepithelial immune lesions can develop and scatter light, which temporarily reduces clarity.

Can nummular keratitis come back?

Recurrence in the same episode is uncommon once lesions resolve, but new adenoviral infections in the future can trigger similar changes.

References

American Academy of Ophthalmology (EyeWiki). ?Epidemic Keratoconjunctivitis.? https://eyewiki.org/Epidemic_Keratoconjunctivitis

American Academy of Ophthalmology. ?Common Types of Eye Infections: Symptoms and Treatment.? https://www.aao.org/eye-health/eye-infections

NCBI Bookshelf (StatPearls). ?Herpes Simplex Keratitis.? https://www.ncbi.nlm.nih.gov/books/NBK545278/

American Academy of Ophthalmology (EyeWiki). ?Herpes Zoster Ophthalmicus.? https://eyewiki.org/Herpes_Zoster_Ophthalmicus

PubMed Central (PMC). ?Infectious keratitis: A review.? https://pmc.ncbi.nlm.nih.gov/articles/PMC9542356/