A 65-year-old woman was referred for evaluation of her dry eyes, worse in her right eye than in her left eye. She had a long-standing history of primary open-angle glaucoma for which she was using pilocarpine 1%, timolol 0.5% and dorzolamide eye drops in the right eye. The left eye had not required eye drops since she underwent filtering surgery many years ago. Intraocular pressures measured 13 mm Hg in both eyes. Slit lamp examination of the right eye is as shown in the figure. The left eye did not demonstrate these findings.
The patient most likely has drug-induced ocular cicatrization, also referred to as pseudopemphigoid. These drug-induced cicatrizing changes include chronic conjunctivitis, subconjunctival fibrosis and scarring, and symblepharon formation, all of which can lead to dry eyes, trichiasis and even keratinization of the ocular surface.
A number of ophthalmic topical medications are known to cause cicatrizing changes in the conjunctiva, as seen in our patient. Antiglaucoma medications such as pilocarpine, timolol, epinephrine and echothiophate iodide have all been implicated. Other ophthalmic medications, such as idoxuridine and trifluorothymidine, have also been known to cause these findings.
The causes of chronic cicatrizing conjunctivitis are extensive, including mucous membrane pemphigoid, Stevens-Johnson syndrome, toxic epidermal necrolysis, rosacea, atopic keratoconjunctivitis, Sjögren’s syndrome, sarcoidosis, trachoma, progressive systemic sclerosis, epidemic keratoconjunctivitis, diphtheria conjunctivitis, chemical burns and “pseudopemphigoid.” In these cases, progressive cicatrization of the conjunctiva leads to progressive obliteration of the fornices and inward rotation of the eyelid margins, which then results in damage to the ocular surface from trichiasis and keratinization.
In the absence of history suggesting that the clinical findings may be due to one of the above etiologies, considering conjunctival biopsy is warranted to rule out mucous membrane pemphigoid, as this can be a fatal disease, and immunosuppressive therapy is required.
Given the unilateral presentation of cicatrizing conjunctival changes in this patient’s eye, which had been treated with both pilocarpine and timolol, along with a negative review of systems for mucous membrane pemphigoid, a conjunctival biopsy was not performed. The patient’s eye drop regimen was changed to brimonidine 0.15% twice daily and latanaprost 0.005%. Her cicatrizing changes have not progressed over 2 years of follow up. Her dry eye is being treated with preservative-free artificial tears.