THERAPEUTIC FORUM

Uncovering Hidden Causes of Blepharitis

by Christopher J. Quinn, O.D.

Most of us today can easily diagnose blepharitis in patients who complain of foreign-body sensation, burning and tearing. But if we fail to recognize an underlying condition, our job is only half finished.

Many doctors fail to detect ocular rosacea, often associated with blepharitis. As a result, they often undertreat the condition.

Rosacea is a chronic, recurrent and progressive skin disorder of the face and neck, commonly occurring in patients 20-50 years of age. In its early stages, erythema and telangiectasia, followed by papule and pustule formation, characterize the condition. In advanced stages, patients develop rhinophyma.

Rosacea is most common in white people with fair skin. It's frequently triggered by extreme temperatures, spicy foods, alcoholic beverages, exercise and stress. The pathogenesis is unknown and most likely due to many factors.

This often embarrassing acne condition rarely reverses itself and cannot be cured, but it can be controlled with regular treatment.

Ocular manifestations.
Ocular complications commonly associated with rosacea include low-grade, chronic conjunctivitis, irregularity and telangiectasia of the eyelid margin, and dysfunction of the meibomian gland.

Although these conditions are generally not sight-threatening, the cornea can be severely affected. If corneal lesions recur and progress, the visual prognosis is usually not good.

Patients may complain of mild injection and irritation. They may develop progressive corneal thinning and perforation, as well as severe cicatrizing conjunctivitis. The latter can lead to secondary entropion and corneal breakdown.

Patients can present with a significant conjunctival inflammation that resembles a Type IV hypersensitivity reaction. This inflammatory response is most likely related to the toxic effects caused when the conjunctival cells release inflammatory mediators.

Patients with ocular rosacea also have a higher density of Demodex folliculorum of the eyelid margin. This may act as an antigenic stimulus.

Treatment.
Once you diagnose ocular rosacea, treatment must be both local and systemic.

Local treatment for the blepharitis includes lid scrubs twice daily, followed by the application of topical antibiotics, such as erythromycin or bacitracin ointment, to the lid margin twice daily. Metronidazole 1 percent gel or cream is particularly useful because it also has anti-inflammatory properties. (If your patient has problems maintaining compliance, Noritate, a new formulation of metronidazole, might be a better choice because it's applied just once a day.)

To alleviate symptomatic conjunctival inflammation, use topical steroids such as flourometholone or Alrex (loteprednol etabonate) one drop four times a day until the patient's symptoms improve.

Watch the corneal surface carefully, since steroids increase the risk of secondary bacterial infection in an already compromised ocular surface.

Besides local treatment, oral tetracycline 250mg four times a day or one of its derivatives will reduce the symptoms associated with ocular rosacea. Doxycycline 100mg twice a day for four weeks, then slowly tapered, may reduce those symptoms, too.

Despite this treatment, some patients with rosacea may require a low dose of long-term treatment to prevent acute exacerbations. Ongoing lid hygiene is critical. Doxycycline 50mg per day might also aid prevention.

Of course, you must be aware of the potential adverse effects of tetracycline use: gastrointestinal upset, photosensitivity and increased intra-cranial pressure. It is contraindicated in patients younger than 12 years, or in pregnant and lactating women.

If you recognize the underlying ocular rosacea and treat it appropriately, you'll increase your success in treating chronic blepharitis and your patients' level of comfort as well.