Table of contents

Other Keratitis Manifestations

Inflammation of the cornea can manifest in several specific ways that are distinct from infective keratitis. These manifestations are reviewed on this page.

Interstitial Keratitis (IK)

Interstitial keratitis is an inflammation of the corneal stroma. There are many causes of IK and the high-yield ones are discussed in this section.

Pathology

Inflammation of the corneal stroma in the absence of primary epithelial or endothelial involvement.
Over time, this inflammation leads to scarring which looks feather-like and has associated ghost vessels.

Causes

Disease	Key Features
Syphilitic IK	Typically seen in congenital syphilis Presentation is bilateral: IK, notched teeth and deafness Tx: IM benzylpenicillin
Cogan Syndrome	Autoimmune IK associated with hearing loss, vertigo, tinnitus and polyarteritis nodosa Tx: steroids
Lyme Disease	Caused by Borrelia, transmitted by tick bite, resulting in the characteristic skin lesion: erythema migrans Patientation: IK, uveitis, arthralgia, loss of lateral eyebrows and facial palsy

Erythema migrans in patient with Lyme disease.

Peripheral Ulcerative Keratitis (PUK)

Inflammation around the corneal circumference rather than the central cornea is characteristic of some important corneal and extra-corneal diseases.

Pathology

Inflammation/ulceration progresses centrally and posteriorly in most cases.
PUK is typically either caused by infection or a systemic autoimmune disorder.

In practice, PUK is caused by infection until proven otherwise. Finding PUK in isolation, in the absence of other ocular pathology is suggestive of a systemic autoimmune disorder.

Systemic Autoimmune Associations

Rheumatoid arthritis - the most common systemic autoimmune cause of PUK
Granulomatosis with polyangiitis (GPA)
Crohn's
SLE
Polyarteritis nodosa

Filamentary keratitis

A common condition caused by mucous and strand adhesion to the corneal surface due to degenerations of the corneal epithelium. It can cause severe discomfort.

Diagnostics

Slit Lamp biomicroscopy of filamentary keratitis By Imran kabir hossain, CC BY-SA 4.0.

Presentation

Typically found in cases of abnormal tear film such as dry eye, LASIK and contact lens wearers.
Patients present with watery, irritated red-eye with a foreign body sensation.

Investigations

Rose bengal staining of the corneal surface shows comma-shaped lesions which move whilst blinking.

Management

Mucolytics such as acetylcysteine drops.
NSAID drops to address discomfort.

Mooren Ulcer

Mooren ulcer is a distinctive peripheral corneal disorder caused by autoimmune stromal ulceration.

Diagnostics

Presentation

Pain, photophobia and blurry vision.
Characteristic peripheral corneal ulcer with an undefined edge

Management

Immunomodulation with steroids.
Oral tetracyclines can be used for their anti-collagenase effects.