SIGNS AND SYMPTOMS:
Most viral infections cause mild, limited conjunctivitis, but some infections can cause severe visual impairment. The two most common forms of viral conjunctivitis are epidemic keratoconjunctivitis and pharyngoconjunctival fever
Pharyngoconjunctival fever is characterized by fever, sore throat, and follicular conjunctivitis. It may be unilateral or bilateral. It is most commonly caused by adenovirus 3 and less often by adenovirus 4 or 7. Corneal infiltrates are rare. The severity of the disease varies, but most often its duration is between 4 days and 2 weeks. While the virus disappears from the conjunctiva for about 14 days, it remains in the feces for about 30 days.
Epidemic keratoconjunctivitis most commonly manifests as bilateral, palpebral, follicular conjunctivitis with epithelial and stromal keratitis. Suppressive corneal infiltrates are much more common in epidemic keratoconjunctivitis than in pharyngoconjunctival fever and are concentrated in the central part of the cornea. Epidemic keratoconjunctivitis is most commonly caused by adenoviruses 8 and 19.
Key symptoms of both conditions include conjunctival inflammation, lacrimation, serous secretions, edematous eyelids, subconjunctival hemorrhages, pseudomembranous formations, and palpating preauricular lymph nodes. In severe cases, conjunctiva of the eyelid conjunctiva and the eyeball is observed.
Both conditions are highly contagious. Most patients report having had contact with people who had red eyes or upper respiratory tract infection. Both conditions initially affect one eye and later spread to the other.
Viral conjunctival infections are transmitted via the airborne and social pathways. After an incubation period of 5 to 12 days, the disease enters its acute phase, causing watery secretion, conjunctival hyperemia, and follicular formations. The lymph follicles are enlarged, with avascular lesions ranging from 0.2 to 2 mm. They have germination centers that are activated against the infectious agent.
Adenovirus type 8 can proliferate in the corneal epithelial structures and cause characteristic keratitis and subtle infiltrates. This, together with the immune response to the viral agents, leads to a lymphocyte buildup in the anterior stroma, just below the epithelium. Sometimes a conjunctival membrane is formed, which consists of fibrin and leukocytes, and in some cases, collagen and fibroblasts. Pseudomembranes are much easier to remove than “true membranes”.
Because both forms of viral conjunctivitis are highly contagious, treatment is focused on prevention. Patients should be instructed not to go to work or school until water secretion has ceased. In addition, they should be explained not to use common towels, goggles and lens contacts with others.
Medical treatment can range from student compresses and artificial tears to topical vasoconstrictors – for example, naphazoline, and steroids two to four times a day. In the presence of membranes, they should be removed with a damp cotton applicator or forceps. Following their removal, a topical antibiotic-steroid such as Tobradex should be prescribed. Antiviral drugs like viroptic are ineffective against adenovirus.
More recently, there has been progressing in the treatment of eye infections caused by adenoviruses. Cidofovir, an antiviral drug administered intravenously against cytomegalovirus retinitis, has also been shown to be effective in adenoviral keratoconjunctivitis. It is recommended to administer the topical form twice daily. Topical form is also assumed to be effective in herpes simplex, zoster and Ebstein-bar virus.
IMPORTANT CLINICAL FEATURES:
– Keep your equipment, tools, and furniture clean so that you do not infect your patients and staff.
– most ophthalmologists use topical steroids only in the most severe cases (for example, if the infection is on the visual axis and affects visual acuity), as well as in recurrent infections. Infiltrates caused by epidemiological keratoconjunctivitis pass without scarring on the cornea
– Tell your patients to expect the symptoms to get worse for 7 to 10 days, and that the infection will not go away completely for at least 3-6 weeks. And remember – don’t stop steroids all of a sudden.