Epidemic Keratoconjunctivitis (EKC) Clinical Presentation

Updated: Jun 04, 2019
  • Author: Ahmed Bawazeer, MBChB, FRCSC; Chief Editor: Hampton Roy, Sr, MD  more...
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Epidemic keratoconjunctivitis infection may be preceded by flulike symptoms, including fever, malaise, respiratory symptoms, nausea, vomiting, diarrhea, and myalgia.

Often, a recent history of an eye examination or exposure within the family or at work is present.

The incubation period is 2-14 days, and the person may remain infectious for 10-14 days after symptoms develop.

The ocular symptoms are mainly sudden onset of irritation, soreness, red eye, photophobia, foreign body sensation, and excessive tearing.

In more severe cases, patients can present with ocular and periorbital pain and decreased visual acuity.

Symptoms tend to last for 7-21 days. The fellow eye tends to be involved in more than 50% of the cases within 7 days of onset. The signs and symptoms are typically less severe in the fellow eye.


Physical Examination

Ipsilateral preauricular lymphadenopathy is one of the classic findings of epidemic keratoconjunctivitis (EKC).

Decreased visual acuity is rarely present; it is usually present only if there is corneal involvement.

Other clinical signs include the following:

  • Swelling and erythema of the lid

  • Conjunctival hyperemia

  • Chemosis

  • Follicular reaction, mainly in the lower palpebral conjunctiva (the earliest and most common sign)

  • Papillary hypertrophy

  • Subconjunctival and petechial hemorrhage

In severe cases, membranous and pseudomembranous conjunctivitis can be seen in one third of cases, which can lead to conjunctival scarring and symblepharon (seen in the image below).

Symblepharon secondary to epidemic keratoconjuncti Symblepharon secondary to epidemic keratoconjunctivitis.

Corneal involvement

One of the distinguishing features of EKC is corneal involvement, which is usually mild and transient.

Corneal involvement has been well documented 3-4 days after symptom onset in the form of diffuse, fine epithelial keratitis that stains with fluorescein and rose bengal. This keratitis can persist for 2-3 weeks. In rare cases, a frank corneal epithelial defect may occur.

One week after the onset, focal epithelial keratitis may develop. This is characterized by central ulceration and irregular borders with gray-white dots. These epithelial changes are related to active viral infection. These lesions persist for 1-2 weeks.

About 2 weeks after onset, subepithelial infiltrates can appear beneath the focal epithelial lesions, persisting for weeks to years. They resolve spontaneously, usually without scarring. These infiltrates are immunologic in nature.

In rare cases, disciform keratitis or anterior uveitis can occur.

There is no change in corneal sensation.