Five-year-old girl with redness and light sensitivity of the right eye of 2 days' duration. She denied any significant pain or decreased vision. She initially presented to an urgent care clinic, where application of polymyxin B/trimethoprim eye drops 4 times a day was prescribed.
Five-year-old girl with redness and light sensitivity of the right eye of 2 days' duration. She denied any significant pain or decreased vision. She initially presented to an urgent care clinic, where application of polymyxin B/trimethoprim eye drops 4 times a day was prescribed. Her symptoms had persisted despite this treatment. The mother was concerned because her daughter had kept the right eye closed since she awoke that morning. She also had noticed minimal clear discharge from the eye.
Otherwise healthy child with no chronic medical conditions. She was given no medications other than the eye drops. She had no fevers, headaches, or difficulty in swallowing;
no history of recent travel or travel abroad; and no pets. Family was unaware of any other children (in day care or neighborhood) with “pink eye.”
Alert, active child in slight distress related to her right eye. She was afebrile. Vital signs appropriate for her age. She had no preauricular lymph node enlargement. Systemic examination findings within normal limits.
Visual acuity 20/40 in right eye, 20/30 in left eye. Pupils equal and reactive to light, eyes aligned, and extraocular movements full. Right lower lid slightly edematous and erythematous; no vesicular or pustular lesions noted on the lid margin or periorbital skin. Conjunctiva significantly injected with diffuse tiny gelatinous bumps (A). Corneal light reflex slightly irregular in some areas; cornea otherwise clear. Anterior chamber and red reflex also clear. Left eye completely normal.
Right eye viewed by Wood lamp after application of fluorescein dye as shown (B).
WHAT'S YOUR DIAGNOSIS?
ANSWER: HERPES SIMPLEX KERATOCONJUNCTIVITIS
Wood lamp examination after fluorescein dye instillation revealed small branching lesions on both the cornea and conjunctiva, representative of herpes simplex conjunctivitis and keratitis. The girl was referred to ophthalmology. A conjunctival swab sent for herpes simplex virus (HSV) testing by fluorescent antibody revealed HSV type 1. This result was subsequently confirmed by viral culture.
INCIDENCE AND ETIOLOGY
HSV has been identified as the causative agent in as many as 21% of cases of acute follicular conjunctivitis.1 Herpes simplex conjunctivitis can result from primary infection or reactivation of latent HSV infection in the trigeminal ganglion.
Diagnosis of herpes simplex conjunctivitis is usually clinical, based on the characteristic appearance of significantly injected conjunctiva with diffuse tiny gelatinous bumps, which indicate a follicular reaction. About 90% of cases of conjunctivitis caused by HSV are unilateral.2 Primary herpetic conjunctivitis or keratoconjunctivitis is often associated with blepharitis and tender preauricular lymphadenopathy, although this sign is usually absent in recurrent disease.
The conjunctivitis may be associated with keratitis, which is characterized by branching dendrites on the cornea and conjunctiva that appear to have terminal bulbs on close examination. The dendrites stain with fluorescein as well as with Rose Bengal, a vital dye that stains HSV-infected cells at the periphery of the lesions. In cases without corneal involvement, swabbing the conjunctiva for viral culture can confirm the diagnosis. Serology is not useful in diagnosis because the sensitivity and specificity are low for this test.
Herpetic conjunctivitis and even keratitis often resolve spontaneously. However, in untreated cases or with repeated recurrences, keratitis often leaves residual scarring in the shape of a “ghost dendrite” that may affect vision if in the visual axis. Therefore, treatment is advised in all patients with herpes keratoconjunctivitis. Application of topical 1% trifluridine eye drops every 2 hours while awake is the standard therapy for herpetic keratitis. Oral acyclovir or valacyclovir may be used in patients who may not cooperate with topical administration. Recently, a new topical formulation of 0.15% ganciclovir ophthalmic gel, applied 5 times daily, has been approved for use in the United States and may make topical therapy more convenient. Gentle wiping of the corneal lesion can hasten resolution of keratitis; this is because the infected cells adhere poorly and debride easily, while the surrounding normal cells are unaffected.3 Prophylactic therapy with an oral antiviral is recommended for patients with recurrent herpetic eye disease because studies have shown that it decreases the risk of recurrence by 50%.4
OUTCOME IN THIS CASE
This girl was treated with trifluridine eye drops as well as oral acyclovir, and the corneal lesion was debrided with a cotton swab. At follow-up a week later, her symptoms had completely resolved. She had no residual corneal scarring, and her vision was 20/30 in both eyes with Allen cards. She continued treatment with the topical and oral medications for a total of 2 weeks. The mother was informed of the possibility of recurrence and was instructed to bring the child to the ophthalmologist immediately if she notices any eye redness. Prophylactic treatment with oral acyclovir was also offered, but this was deferred.
1. Wishart PK, James C, Wishart MS, Darougar S. Prevalence of acute conjunctivitis caused by chlamydia, adenovirus, and herpes simplex virus in an ophthalmic casualty department. Br J Ophthalmol. 1984;68:653-655.
2. Uchio E, Takeuchi S, Itoh N, et al. Clinical and epidemiological features of acute follicular conjunctivitis with special reference to that caused by herpes simplex virus type 1. Br J Ophthalmol. 2000;84:968-972.
3. Wilhelmus KR. Antiviral treatment and other therapeutic interventions for herpes simplex virus epithelial keratitis. Cochrane Database Syst Rev. 2010;12:CD002898.
4. Young RC, Hodge DO, Liesegang TJ, Baratz KH. Incidence, recurrence, and outcomes of herpes simplex virus eye disease in Olmsted County, Minnesota, 1976-2007: the effect of oral antiviral prophylaxis. Arch Ophthalmol. 2010;128:1178-1183.