eMedicine Specialties > Emergency Medicine > Ophthalmology

Conjunctivitis

Author: Michael A Silverman, MD, Instructor of Emergency Medicine, The Johns Hopkins University School of Medicine; Chairman, Department of Emergency Medicine, Harbor Hospital
Coauthor(s): Edward Bessman, MD, Chairman, Department of Emergency Medicine, John Hopkins Bayview Medical Center; Assistant Professor, Department of Emergency Medicine, Johns Hopkins University
Contributor Information and Disclosures

Updated: Jun 1, 2009

Introduction

Background

Conjunctivitis is one of the most common nontraumatic eye complaints resulting in presentation to the ED. The term describes any inflammatory process that involves the conjunctiva; however, to most patients, conjunctivitis (often called pink eye) is a diagnosis in its own right. Most causes of conjunctivitis are benign, and the role of the emergency physician is to separate those few conditions requiring more vigorous treatment from the majority that can be handled satisfactorily in the ED.

Cellular infiltration and exudation characterize conjunctivitis on a cellular level. Classification usually is based on cause, including viral, bacterial, fungal, parasitic, toxic, chlamydial, chemical, and allergic agents. It also can be based on age of occurrence or course of disease. Etiology often can be distinguished on clinical grounds. In keratoconjunctivitis, an associated corneal involvement is present.

Pathophysiology

The conjunctiva is a loose connective tissue that covers the surface of the eyeball (bulbar conjunctiva) and reflects back upon itself to form the inner layer of the eyelid (palpebral conjunctiva). The conjunctiva firmly adheres to the sclera at the limbus, where it meets the cornea. The accessory lacrimal glands (Krause and Wolfring), along with goblet cells, are contained within the conjunctiva and are responsible for keeping the eye lubricated. As with any mucous membrane, infectious agents may adhere to the conjunctiva, thus overwhelming normal defense mechanisms and producing clinical symptoms of redness, discharge, irritation, and possibly photophobia. Viral etiologies are more common than bacterial, and incidence of viral conjunctivitis increases in the late fall and early spring.

Frequency

United States

Conjunctivitis is considered extremely common in the United States. Three percent of all ED visits are ocular related, and conjunctivitis is responsible for approximately 30% of all eye complaints. Approximately 15% of the population will have an allergic conjunctivitis episode at some time.

International

Conjunctivitis is extremely common.

Mortality/Morbidity

Conjunctivitis typically is a self-limited process; however, depending on the immune status of the patient and the etiology, conjunctivitis can progress to increasingly severe and sight-threatening infections.

• Purulent bacterial conjunctivitis in the neonate usually is caused by Neisseria gonorrhoeae. This type of conjunctivitis can be invasive and can lead to rapid corneal perforation.
• Chlamydial conjunctivitis can lead to conjunctival scarring (cicatrix) that can be severe enough to cause lid derangement and ingrown eyelashes.
• Trachoma is a more chronic, insidious form of Chlamydia trachomatis infection. The condition affects 500 million people worldwide and is considered the leading cause of blindness in the world, blinding approximately 10% of those affected.
• Chlamydial pneumonia can occur in infants up to 6 months after their conjunctivitis.
• Three major agents associated with follicular conjunctivitis, preauricular adenopathy, and superficial keratitis are adenovirus, chlamydia, and herpes simplex. Neisserial species can be associated with adenopathy, but the keratitis is ulcerative and not superficial. Frequently, a history of viral syndrome, sexually transmitted disease (STD), or fever blister can be elicited, which can aid in diagnosing the condition. Adenovirus is extremely contagious. Advise individuals to be diligent with hand washing and to avoid contact with their tears. Sharing pillows, towels, computer keyboards, and anything in contact with infected secretion helps spread the infection, a major cause of missed work hours.

Race

No racial predilection exists.

Sex

No sex predilection exists, although 90% of women with chlamydial eye infections have associated genital infections, and as many as 60% of men have associated genitourinary symptoms.

Age

Conjunctivitis occurs in all ages.

• Conjunctivitis of the newborn is the term used by the World Health Organization (WHO) for any conjunctivitis with discharge occurring during the first 28 days of life. Ophthalmia neonatorum was the term used to describe a hyperacute purulent conjunctivitis, usually caused by gonococci, in the first 10 days of life. In this instance, transmission is vertical.
• Any individual with follicular conjunctivitis or preauricular adenopathy with or without keratitis should be questioned about the possibility of STD; high-risk individuals should be treated empirically for chlamydia.

Clinical

History

In classic presentations, patients complain of eyelids sticking together on waking. They may describe itching and burning or a gritty foreign-body sensation. Pus sliding across the eye may distort vision, though visual acuity is normal. Photophobia is minimal. Family members with similar complaints typically present with conjunctivitis from an infectious cause. A history of a recent upper respiratory infection (URI) typically is associated with a viral cause.

• Bacterial conjunctivitis is characterized by acute onset, minimal pain, occasional pruritus, and, sometimes, exposure history.
  • Ocular surface disease (eg, keratitis sicca, trichiasis, chronic blepharitis) predisposes the patient to bacterial conjunctivitis.
  • Staphylococcal and streptococcal species are the most common pathogens.
• Viral conjunctivitis is characterized by acute or subacute onset, minimal pain level, and, often, exposure history.
  • Pruritus is common. A clear, watery discharge is typical.
  • Occasionally, severe photophobia and foreign-body sensation occurs, usually caused by adenovirus (epidemic keratoconjunctivitis [EKC]), when associated with keratitis.
  • Check for preauricular adenopathy and a follicular conjunctival change, particularly on the palpebral conjunctiva. If present, the likely diagnosis is EKC.
  • Be aware that herpes simplex and chlamydia also cause follicular conjunctivitis and preauricular adenopathy.
• Chlamydial conjunctivitis is characterized by chronic onset, minimal pain level, occasional pruritus, and STD history.
• Allergic conjunctivitis is characterized by acute or subacute onset, no pain, and no exposure history.
  • Pruritus is extremely common. Clear, watery discharge is typical with or without a moderate amount of mucous production.
  • An aggressive form of allergic conjunctivitis is vernal conjunctivitis in children and atopic conjunctivitis in adults. Vernal disease often is associated with shield corneal ulcers. Perilimbal accumulation of eosinophils (Horner-Trantas dots) typifies vernal disease. Vernal keratoconjunctivitis (VKC), usually affecting young boys, tends to be bilateral and occurs in warm weather. VKC is presumed to be a hypersensitivity to exogenous antigens and may be associated with or accompanied by keratoconus.
• Giant papillary conjunctivitis resembles vernal disease.
  • This condition occurs mainly in contact lens wearers who develop a syndrome of excessive pruritus, mucous production, and increasing intolerance to contact use.
  • The giant papillae are predominantly on the upper palpebral conjunctiva and can be seen only on lid eversion.

Physical

On any patient with ocular complaints, perform a complete physical examination of the eye, including visual acuity, fluorescein staining, slit-lamp examination, and tonometry. Specific helpful clues in differentiating the causes of conjunctivitis are listed below.

• Bacterial conjunctivitis
  • Preauricular adenopathy sometimes occurs; chemosis (thickened, boggy conjunctiva) is common.
  • Discharge is copious; discharge quality is thick and purulent. Conjunctival injection is moderate or marked.
• Viral conjunctivitis
  • Preauricular adenopathy is common in EKC and herpes; chemosis is variable.
  • Discharge amount is moderate, stringy, or sparse; discharge quality is thin and seropurulent. Conjunctival injection is moderate or marked.
• Chlamydial conjunctivitis tends to be chronic with exacerbation and remission.
  • Preauricular adenopathy is occasional; chemosis is rare.
  • Discharge amount is minimal; discharge quality is seropurulent. Conjunctival injection is moderate.
• Allergic conjunctivitis occurs with pruritus as the hallmark symptom.
  • Preauricular adenopathy is absent; chemosis is common.
  • Discharge amount is moderate, stringy, or sparse; discharge quality is clear. Conjunctival injection is moderate.
• Marginal ulcers (small white ulcers that appear on the cornea at the limbus) may indicate an allergic reaction to staphylococcal antigen.
  • This is a toxin-related complication of staphylococcal species that frequently cause blepharitis.
  • Pain, photophobia, and a foreign-body sensation are common. The ulcers are sterile and respond to topical steroids.
• Bilateral disease typically is infectious or allergic.
• Unilateral disease suggests toxic, chemical, mechanical, or lacrimal origin.
  • Intraocular pressure, pupil size, and light response are all normal.
  • Ciliary flush, corneal staining, and anterior chamber reaction is absent unless a significant amount of keratitis is associated (as seen in EKC).

Causes

Several studies demonstrate that acute conjunctivitis occurs with almost equal frequency between bacterial and viral causes. Fitch et al noted that viral conjunctivitis occurs more frequently in the summer, and bacterial conjunctivitis occurs more often in the winter and spring.

• Mucopurulent conjunctivitis is caused by bacterial organisms.
  • Gram-positive for the following cocci -Staphylococcus epidermidis, Streptococcus pyogenes, and Streptococcus pneumoniae
  • Gram-negative for the following cocci -Neisseria meningitidis and Moraxella lacunata
  • Gram-negative for the following rods - genus Haemophilus and family Enterobacteriaceae
• Approximately one-third of children had an anaerobic bacterial etiology in studies that used adequate recovery methods. Predominant anaerobic organisms include Clostridium species, gram-negative anaerobic bacilli, and Peptostreptococcus species. 
• Hyperpurulent conjunctivitis usually is caused by N gonorrhoeae.
• N gonorrhoeae, C trachomatis, and other bacteria (mainly staphylococcal species and S pneumoniae) cause conjunctivitis of the newborn. (Approximately 90% of infants receiving Credé prophylaxis [ie, silver nitrate application] for gonorrheal ophthalmologic problems experience a mild, transient conjunctival injection and tearing with variable purulence that typically resolves in 24-48 hours.)
• Many types of viruses, most commonly adenovirus, cause viral conjunctivitis.
• Atopic conjunctivitis typically occurs in male teenagers who have a history of childhood atopic dermatitis. The condition resembles vernal conjunctivitis but is not seasonal.
• Vernal conjunctivitis is a bilateral recurrent hypersensitivity that occurs during the warm months of the year, particularly in hot climates.
• Giant papillary conjunctivitis predominantly is associated with contact lens wear.
• Toxic conjunctivitis occurs with airborne irritants or a direct splash of liquid or powder to the eye.
• Unusual causes may be considered in patients with atypical presentations, including parasitic (eg, Loa loa, Trichinella, Onchocerca), autoimmune (eg, sicca, pemphigoid), and systemic diseases (eg, sarcoidosis, tuberculosis, Reiter syndrome, Kawasaki disease).

• Search for CME/CE on This Topic »

• Conjunctivitis, Neonatal (Ophthalmology)
• Conjunctivitis, Viral (Ophthalmology)
• Conjunctivitis, Giant Papillary (Ophthalmology)
• Arthritis, Conjunctivitis, Urethritis Syndrome (Pediatrics: General Medicine)

• Pinkeye Causes
• Pinkeye Overview
• Pinkeye Treatment
• Eye and Vision Center
• Pinkeye Symptoms

• FDA Approves Besifloxacin for Bacterial Conjunctivitis
• FDA Approves Bepotastine Ophthalmic Solution for Treating "Allergy Eyes"
• Occupational Exposure to Coffee Dust Can Cause Health Problems

• Common Ophthalmic Emergencies
• Identification and Control of Nosocomial Adenovirus Keratoconjunctivitis in an Ophthalmic Department
• Contact Lenses and Allergy