2.02 Conjunctivitis (Pink Eye)
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agk's Library of Common Simple Emergencies

Presentation
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The patient complains of a red eye, a sensation 
of fullness, burning, itching, or scratching, 
and perhaps a gritty or foreign body sensation 
and tearing or purulent discharge and crusting 
or mattering. Examination discloses generalized 
injection of the conjunctiva, thinning out 
towards the cornea (localized inflammation 
suggests some other diagnosis such as a foreign 
body, episcleritis, or a viral or bacterial 
ulcer). Vision and pupillary reactions should 
be normal and the cornea and anterior chamber 
should be clear. Any discomfort should be 
temporarily relieved by instilling topical 
anesthetic solution. Deep pain, photophobia, 
decreased vision and injection more pronnounced 
around the limbus (ciliary flush) suggest more 
serious involvement of the cornea and iris.

Different symptoms suggest different etiolog- 
ies. Tearing, preauricular lymphadenopathy and 
upper respiratory symptoms suggest a viral 
conjunctivitis. Pain upon awakening with lid 
crusting and a copious purulent exudate 
suggests a bacterial conjunctivitis. Few 
symptoms upon awakening but discomfort 
worsening during the day suggests a dry eye. 
Little conjunctival injection with a seasonal 
recurrence of chemosis and itching, and 
cobblestone hypertrophy of the tarsal conjunct- 
iva suggests allergic (vernal) conjunctivitis. 
Physical and chemical conjunctivitis, caused by 
particles, solutions, vapors, natural or 
occupational irritants that inflame the con- 
junctiva, should be evident from the history.

What to do:
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- Instill proparcaine anesthetic drops 
   (Alcaine, Ophthaine) to allow for a more 
   comfortable exam and to help determine if 
   the patient's discomfort is limited to the 
   conjunctiva and cornea or, if there is no 
   pain relief, that the pain comes from deeper 
   eye structures.
- Examine the eye, including visual acuity, 
   inspection for foreign bodies, pupillary 
   reaction fundoscopy, estimation of intra- 
   ocular pressure by palpation of the globe 
   above the tarsal plate, slit lamp exam- 
   ination (when available), and fluorescein 
   and ultraviolet or cobalt blue light to 
   assess the corneal epithelium.
- Ask about and look for any rash, arthritis, 
   or mucous membrane involvement which could 
   point to Stevens-Johnson syndrome, 
   Kawasaki's, Reiter's, or some other syndrome 
   that can present with conjunctivitis.
- For bacterial conjunctivitis, start the 
   patient on warm compresses and seven days of 
   topical antibiotics such as erythromycin, 
   sulfacetamide, tobramycin or gentamycin 
   ointment (which transiently blurs vision) 
   every 4 hours, or solutions such as 
   sulfacetamide 10%, tobramycin 0.3% or 
   ciprofloxacin every 2 hours, with oral 
   analgesics as needed. If it is unclear 
   whether the problem is viral or bacterial, 
   it is safest to treat it as bacterial.
- For viral and chemical conjunctivitis, use 
   cold compresses and weak topical vasoconst- 
   rictors such as naphazoline 0.1% (Naphcon) 
   every 3-4 hours, unless the patient has a 
   shallow anterior chamber that would be prone 
   to acute angle-closure glaucoma with 
   mydriatics.
- For allergic conjunctivitis, use cold 
   compresses and topical decongestant- 
   antihistamine combinations such as drops of 
   naphazoline with pheniramine (Naphcon A) or 
   naphazoline with antazoline (Vasocon A) 
   every 3-4 hours. Topical corticosteroid 
   drops provide dramatic relief, but prolonged 
   use increases the risk of opportunistic 
   viral, fungal and bacterial corneal ulcer- 
   ation, cataract formation and glaucoma. If a 
   severe contact dermatitis is suspected, then 
   a short course of oral prednisone would be 
   indicated.
- If the problem is dry eyes (keratoconjunctiv- 
   itis sicca) use methylcellulose (Dacriose) 
   artificial tear drops.
- Have the patient follow up with the ophthal- 
   mologist if the infection does not clearly 
   resolve in 2 days. Obtain early consultation 
   there is any involvement of cornea or iris.

What not to do:
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- Do not forget to wash your hands and 
   equipment after examining the patient, or 
   you may spread herpes simplex or epidemic 
   keratoconjunctivitis to yourself and other 
   patients. Also, do not forget to instruct 
   the patient on the importance of hand 
   washing and separation of towels and pillows 
   for ten days after the onset of symptoms.
- Do not patch an affected eye, as this 
   interferes with the cleansing function of 
   tear flow.
- Do not give steroids without arranging for 
   ophthalmologic consultation, and never give 
   steroids if a herpes simplex infection is 
   suspected.

Discussion
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Warm compresses are soothing for all types of 
conjunctivitis, but antibiotic drops and 
ointments should be reserved for when bacterial 
infection is likely. Neomycin-containing 
ointments and drops should probably be avoided, 
because allergic sensitization to this anti- 
biotic is common. Any corneal ulceration 
requires ophthalmological consultation. Most 
viral and bacterial conjunctivitis will resolve 
spontaneously, with the possible exception of 
staphylococcus, meningiococcus, and gonococcus 
infections, which can produce destructive 
sequelae without treatment.

Most bacterial conjunctivitis is caused by 
Streptococcus pneumoniae, Haemophilus aegyptus 
and Staphylococcus aureus. Routine conjunctival 
cultures are seldom of value, but you should 
Gram stain and culture a copious purulent 
exudate. Neisseria gonorrhoeae infection 
confirm-ed by Gram-negative intracellular 
diplococci on Gram stain requires immediate 
ophthalmologic consultation. Corneal ulcer- 
ation, scarring and blindness can occur in a 
matter of hours. Chlamydial conjunctivitis will 
usually present with lid droop, mucopurulent 
discharge, photophobia and preauricular lymph- 
adenopathy. Small white elevated conglomera- 
tions of lymphoid tissue can be seen on the 
upper and lower tarsal conjunctiva, and 90% of 
patients have concurrent genital infections. 
Doxycycline 100mg bid or erythromycin 400mg tid 
by mouth plus topical tetracycline (Achromycin 
Ophthalmic) for three weeks should control the 
infection (also treat any sexual partner).

Epidemic keratoconjunctivitis is a bilateral, 
painful, highly contagious conjunctivitis 
usually caused by an adenovirus. The eyes are 
extremely erythematous, sometimes with sub- 
conjunctival hemorrhages. There is copious 
watery discharge and preauricular lymph- 
adenopathy. Treat the symptoms with analgesics, 
cold compresses, and, if necessary, cortico- 
steroids. Because the infection can last as 
long as three weeks and may result in permanent 
corneal scarring, provide ophthalmologic 
consultation and referral. Herpes simplex 
conjunctivitis is usually unilateral. Symptoms 
include a red eye, photophobia, eye pain and 
mucoid discharge. There may be periorbital 
vesicles, and a branching (dendritic) pattern 
of fluorescein staining makes the diagnosis. 
Treat with trifluridine 1% (Viroptic), 
analgesics and cold compresses. Cycloplegics 
such as homatropine may help control pain from 
iridocyclitis. Topical corticosteroids are 
contraindicated, because they can extend the 
infection, and ophthalmological consultation is 
required.

Herpes zoster ophthalmicus is shingles of the 
opthalmic branch of the trigeminal nerve, which 
innervates the cornea and the tip of the nose. 
It begins with unilateral neuralgia, followed 
by a vesicular rash in the distribution of 
nerve. Ophthalmic consultation is again 
required, because of frequent ocular consult- 
ations, but topical corticosteroids may be 
used. Prescribe systemic acyclovir (Zovirax) 
800mg q4h (five times a day) for ten days or 
famcyclovir (Famvir) 500mg tid for seven days.

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