Rosacea ocular

The pH of the normal tears has been determined by many investigators to have a mean value of 7.4, but there are wide variations. It is lowest on awakening as a result of acid by-products associated with relatively anaerobic conditions in prolonged lid closure and increases because of loss of carbon dioxide as the eyes open. The tears are more acid in contact-lens wearers due to the impediment of the efflux of carbon dioxide, and more alkaline in the case of diseases such as dry eye, severe ocular rosacea and lacrimal stenosis. 

Etiology. Acne rosacea, better described as rosacea, may be associated with acne but is not caused by it. Rosacea is a chronic, fecial, inflammatory skin disorder frequently related to infectious blepharitis. Rosacea affects the face, nose, chin, and forehead. It has been reported to occur in up to 10% of the population and roughly 14 million Americans. It affects mostly fair-skinned individuals with an onset of between 20 and 50 years. It is characterized by periods of exacerbation that may be mild to very severe. One of the many forms of rosacea is ocular rosacea. 

Stone DU, Chodosh J. Ocular rosacea an update on pathogenesis and therapy. Curr Opin Ophthalmol 2004 15 499-502. 

Figure 25-22 Ocular rosacea with conjunctivitis, maculo-pustular involvement of skin, and rhinophyma. (Courtesy William Wallace, O.D.)...

In most instances patients demonstrate significant improvement of clinical symptomatology and physical signs in the first 2 to 3 weeks. Many patients, however, require chronic therapy and demonstrate exacerbations of the disease during its course. Metronidazole (MetroGel) is a topical gel developed to treat the skin of the facial area in patients with chronic disease and thus reduce the reliance on oral antimicrobial agents. It is applied twice daily. Although not yet an approved use, metronidazole gel applied to the eyelids was found to be an effective treatment of ocular rosacea. 

Although topical antibiotics are used frequently in the management of ocular rosacea, no firm evidence demonstrates their efficacy as a sole therapeutic agent. Topical steroids, however, are effective for treating the inflammatory aspects and frequently are used four times daily in conjimction with antibiotics in combination products such asTobraDex (tobramycin-dexamethasone), Pred-G (gentamicin-prednisone), or Maxitrol (neomycin-polymyxin B-dexamethasone). Because of potential steroid-induced side effects, chronic use of these agents should be avoided. 

Barnhorst DA Jr, Foster JA, Chern KC, Meisler DM. The efficacy of topical metronidazole in the treatment of ocular rosacea. Ophthalmology 1996 103 1880-1883. 

Frucht-Pery J, ChayetAS, Feldman ST, et al.The effect of doxycy-cUne on ocular rosacea. Am J Ophthalmol 1989 107 434-435. 

There are many other causes of RCE, but they occur much less frequently. Among these causes are chemical or thermal burns, herpes simplex keratitis, neuroparalytic keratitis, bullous keratopathy, severe dry eyes, nocturnal lagophthalmos, diabetes mellitus, meibomian gland dysfunction, ocular rosacea, and Alport syndrome. Approximately 5% to 30% of RCEs occur spontaneously without any known predisposing fector. 

Mild burning was common in one retrospective review of topical azithromycin for adults with ocular rosacea [109 ]. While one RCT reported no adverse events post keratoplasty [110 ]. Another reported ocular adverse events in 40% contact lens-related dry eye patients, including conjunctival hyperaemia, conjunctival oedema, punctate keratitis, irritation, pain and foreign body sensation [111 ]. 

MantelH F, Di Zazzo A, Sacchetti M, Dianzani C, Lambiase A, Bonini S. Topical azithromycin as a novel treatment for ocular rosacea. Ocul Immunol Inflamm 2013 21(5) 371-7. 

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