Inflammation of palpebral and/or bulbar conjunctiva. Pink eye refers to non-Neisseria bacterial conjunctivitis.

• System(s) affected: Nervous, Skin/Exocrine
• Genetics:
  N/A
• Incidence/Prevalence in USA: Unknown, but common
• Predominant age: Depends on cause
• Predominant sex: Male = Female

• General
  • Conjunctival hyperemia
  • Burning
  • Foreign body sensation
  • Pruritus
  • Lacrimation
  • Exudation and matting
  • Chemosis
  • Pseudoptosis
  • Preauricular adenopathy
  • Tarsal plate papillary hypertrophy
  • Tarsal plate lymphoid follicles
  • Pseudomembranous and membranes
  • Photosensitivity
  • Decreased acuity if there is complicating ulcer or keratitis
  • Granulomas (rare)
• Bacterial
  • Minimal pruritus
  • Moderate tearing
  • Profuse exudate, particularly Neisseria species
  • Usually unilateral (or initially unilateral)
  • Small tarsal plate papillae
  • Neisseria species may cause chemosis
  • Gram and Giemsa stain: Polymorphonuclear neutrophils (PMN's) and bacteria (gram negative intracellular diplococci with Neisseria species)
• Viral
  • Minimal pruritus
  • Profuse tearing
  • Minimal exudate
  • Often bilateral
  • Preauricular adenopathy common
  • Subconjunctival hemorrhage (acute hemorrhagic conjunctivitis)
  • Associated viral systemic symptom (fever, myalgia, etc.)
  • Tarsal plate follicles
  • Pharyngeal follicles if associated pharyngitis
  • Gram and Giemsa stain: Mononuclear cells (lymphocytes)
  • Rare chemosis except with epidemic keratoconjunctivitis
  • Subepithelial corneal opacities with epidemic keratoconjunctivitis
  • Diffuse punctate corneal fluorescein uptake or dendrites with herpes simplex
  • Typical zoster rash along ophthalmic branch of trigeminal nerve with varicella-zoster blepharoconjunctivitis
  • Typical measles rash, Koplik's spots, etc. with measles
• Chlamydial
  • Minimal pruritus
  • Moderate to profuse tearing
  • Profuse exudate (sometimes modest)
  • Often bilateral
  • Small tarsal plate papillae
  • Tarsal plate follicles present
  • Gram and Giemsa stain: PMN's, plasma cells, inclusion bodies, in trachoma large palely staining lymphoblastic cells
  • Inclusion conjunctivitis commonly has preauricular adenopathy and large tarsal plate papillae and follicles. Occasionally associated genitourinary symptoms in young adults or history of bilateral conjunctivitis unresponsive to topical antibiotics.
  • Lymphogranuloma venereum is rare and non-follicular (mostly granulomatous conjunctival) with large preauricular node (visible bubo)
  • Trachoma rare in the USA (except American Indians of Southwest) and has 4 clinical stages
• Allergic
  • Severe pruritus
  • Moderate tearing
  • No exudate
  • Bilateral
  • Chemosis very common
  • Tarsal papillae
  • Gram and Giemsa's stain: Eosinophils and basophils
  • Allergic rhinoconjunctivitis has associated sneezing, rhinitis but if not of sufficient duration will not develop papillae
  • Vernal conjunctivitis is recurrent in warm weather associated with large "cobblestone" papillae in those with history of atopic allergy
  • Giant papillary conjunctivitis has similar appearance to vernal conjunctivitis with less pruritus and is seen in soft (and occasionally hard) contact lens use
• Chemical or irritative
  • Tarsal follicles with conjunctivitis of topical medications
  • Tearing and exudation depends on toxicity of chemical
  • Chemosis common in post therapeutic irrigation
  • Gram and Giemsa stain: PMN's if tissue necrosis

• Bacterial
  • Staphylococcus aureus
  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Neisseria gonorrhoeae
  • Neisseria meningitidis
  • Rarely other Streptococcal sp., pseudomonas, Branhamella catarrhalis, Coliforms, Klebsiella, Proteus, Corynebacterium diphtheriae, Mycobacterium tuberculosis, Treponema pallidum
• Viral
  • Adenoviruses types 3, 4, 7 (pharyngitis with conjunctivitis)
  • Adenoviruses types 8 and 19 (epidemic keratoconjunctivitis)
  • Adenovirus 11, Coxsackie A24, enterovirus 70 (acute hemorrhagic conjunctivitis)
  • Herpes simplex (primary and recurrent)
  • Coxsackievirus type A28
  • Molluscum contagiosum
  • Varicella
  • Herpes zoster
  • Measles virus
• Chlamydial
  • Chlamydia trachomatis (trachoma)
• Allergic
  • Rhinoconjunctivitis (hay fever) - humoral
  • Vernal conjunctivitis
  • Giant papillary conjunctivitis
  • Delayed (cellular)
  • Autoimmune (Sjögren's, pemphigoid, Wegener's granulomatosis)
• Chemical or irritative
  • Topical medication
  • Home/industrial chemicals
  • Wind
  • Smoke
  • Ultraviolet light
• Other
  • Rickettsial, fungal, parasitic, tuberculosis, syphilis, Kawasaki disease
  • Thyroid disease, gout, carcinoid, sarcoidosis, psoriasis, Stevens-Johnson syndrome, Ligneous conjunctivitis, Reiter's syndrome

Numerous, including trauma from wind, cold and heat, chemicals and foreign body