CAUSES:
1. Viral
. Adenovirus (common cold)
. Coxsackie
. Enterovirus (acute hemorrhagic conjunctivitis)
. Herpes simplex , primary and recurrent
. Herpes zoster or varicella
. Molluscum contagiosum
. Measles, mumps or influenza
2.. Bacterial
. Staphylococcus aureus
. S. epidermidis
. Streptococcus pneumoniae
. Haemophilus influenzae (especially in children)
. Pseudomonas species (must rule out in contact lens users; frequently progresses to corneal ulcers)
. Neisseria gonorrhoeae
. Neisseria meningitidis
. Chlamydia trachomatis causes a chronic
conjunctivitis - gradual onset over 4 weeks
3. Allergic
. Hay fever, seasonal allergies
. Vernal conjunctivitis/atopy
4. Nonspecific
. Irritative: topical medications, wind, or dry eye,
ultraviolet light exposure, smoke
5. Autoimmune: Sjogrens, pemphigoid, Wegener granulomatosis
6. Rare: Rickettsial, fungal, parasitic, tuberculosis, syphilis, Kawasaki disease, Grave disease, gout, carcinoid, sarcoid, psoriasis, Stevens-Johnson, Reiter syndrome
7. FOREIGN BODY
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DIFFERENTIAL DIAGNOSIS
β’ Uveitis (iritis, iridocyclitis, choroiditis): limbal fl ush (red band at corneal margin, less on other areas of conjunctiva)
hazy anterior chamber, decreased visual acuity
β’ Penetrating ocular trauma: ophthalmologic emergency; hospitalize
β’ Acute glaucoma (ophthalmologic emergency) headache, corneal clouding, decreased visual acuity
β’ Corneal ulcer(s) or foreign body: abnormal fl uorescein exam
β’ Dacryocystitis: tenderness and swelling over tear sac (near nasal bridge)
β’ Scleritis and episcleritis: red injected vessels are radially oriented, sectoral (pie wedge) infl ammation, sometimes with nodularity of sclera
β’ Ophthalmia neonatorum: neonates in first 2 days of life - gonococcal; 5-12 days of life - chlamydial, consider HSV if maternal cultures were positive for herpes simplex. Consider specialty consultation. All of these
require systemic therapy as well as topical.
β’ Usually not needed initially for the most common causes of conjunctivitis
β’ Culture swab if thought to be bacterial or if contact lens user
β’ Gram stain of discharge if thought to be gonococcal
DIAGNOSTIC PROCEDURES :
β’ Document visual acuity/Snellen Chart
β’ Fluorescein staining to detect foreign bodies, corneal ulcers or punctate keratitis, and look for dendritic lesions of herpes simplex or zoster
β’ Examine eyelid skin also for herpetic vesicles, lice or nits, blepharitis or styes