Acute Conjunctivitis (Pink Eye)

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, although 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) is typically associated with a viral cause.

In any patient with ocular complaints, perform a complete physical examination of the eye, including visual acuity, fluorescein staining, slit-lamp examination, and tonometry.

In prospective observational cohort study of 368 patients, Meltzer et al sought to identify children at low risk for bacterial conjunctivitis. The combination of 4 clinical factors was found to be independently associated with a negative conjunctival culture result, as follows:

• Age 6 years or older

• Presentation in April through November

• No or watery discharge

• No glued eye in the morning

When 3 factors were present, 76.4% of patients had a negative culture, and when 4 factors were present, 92.3% of patients had a negative culture result. ^[2]

Bilateral versus unilateral disease

Bilateral disease is typically infectious or allergic. Unilateral disease suggests toxic, chemical, mechanical, or lacrimal origin. Intraocular pressure, pupil size, and light response are all normal in unilateral disease, and ciliary flush, corneal staining, and anterior chamber reaction is absent unless a significant amount of keratitis is associated (as seen in epidemic keratoconjunctivitis [EKC]).

Bacterial conjunctivitis is primarily caused by several pathogens, including Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus species, Moraxella catarrhalis, and, less frequently, Chlamydia trachomatis. Gonococcal conjunctivitis, resulting from Neisseria gonorrhoeae, typically occurs through sexual contact with an infected individual. ^[3]

In newborns, ophthalmia neonatorum (neonatal conjunctivitis) can develop due to maternal infections with gonococci or chlamydia, affecting 20-40% of infants born through an infected birth canal.

The condition is characterized by a rapid onset, minimal discomfort, occasional itching, and sometimes a relevant exposure history. Individuals with pre-existing ocular surface diseases, such as keratitis sicca or chronic blepharitis, are at higher risk of developing bacterial conjunctivitis.

Common symptoms include preauricular adenopathy, chemosis (swelling of the conjunctiva), and a copious, thick, purulent discharge, along with moderate to severe conjunctival injection.

Chlamydial conjunctivitis

Chlamydial conjunctivitis is characterized by chronic onset, minimal pain level, occasional pruritus, and a history of sexually transmitted disease (STD). This condition tends to be chronic with exacerbation and remission. Occasional preauricular adenopathy is present, but chemosis is rare. The conjunctival discharge amount is minimal with a seropurulent quality. There is moderate conjunctival injection. Chlamydial conjunctivitis encompasses trachoma, adult inclusion conjunctivitis, and neonatal inclusion conjunctivitis. ^[3]

Viral conjunctivitis is a highly contagious acute infection of the conjunctiva, primarily caused by adenoviruses. ^[4] Symptoms include irritation, photophobia, and watery discharge. Diagnosis typically is clinical, though viral cultures or immunodiagnostic tests may be necessary in some cases. While the infection is usually self-limiting, severe instances may require topical corticosteroids.

Viral conjunctivitis often occurs alongside common colds and other systemic viral infections, such as measles, chickenpox, rubella, and mumps. The condition is characterized by a rapid onset, minimal pain, and often a history of exposure. Common symptoms include itching and a clear, watery discharge, with occasional severe photophobia and a foreign-body sensation, particularly in cases of epidemic keratoconjunctivitis (EKC) associated with keratitis.

Diagnosis may involve checking for preauricular adenopathy and follicular changes in the conjunctiva, especially on the palpebral conjunctiva; the presence of these signs suggests EKC. Both herpes simplex and chlamydia can also cause similar symptoms. Preauricular adenopathy is common in EKC and herpes, while chemosis varies. The conjunctival discharge typically is moderate, stringy, or sparse, with a thin, seropurulent quality, and there is moderate to marked conjunctival injection.

Allergic conjunctivitis is an inflammation of the conjunctiva that can be acute, intermittent, or chronic, typically triggered by airborne allergens. ^[5] Symptoms include intense itching, tearing, discharge, and conjunctival redness (hyperemia). Diagnosis is made clinically, and treatment involves topical antihistamines and mast cell stabilizers. The condition is characterized by a rapid onset, absence of pain, and no relevant exposure history. Itching is the hallmark symptom, and the discharge is usually clear and watery, sometimes accompanied by moderate mucus.

A more severe form of allergic conjunctivitis includes vernal conjunctivitis in children and atopic conjunctivitis in adults. Vernal conjunctivitis is often linked to shield corneal ulcers and is marked by the presence of eosinophils around the limbus (Horner-Trantas dots). It typically affects young boys, is bilateral, and occurs in warm weather, presumed to be a hypersensitivity to external antigens, and may be associated with keratoconus.

In allergic conjunctivitis, preauricular adenopathy is absent, while chemosis is common. The conjunctival discharge is moderate, stringy, or sparse, with a clear appearance, and there is moderate conjunctival injection.

Marginal ulcers

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.

Giant papillary conjunctivitis resembles vernal disease. This condition occurs mainly in contact lens wearers. These patients 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. Increased deposition may also be seen on the contact lens of the affected eye.

Prehospital transport is rarely indicated for patients with conjunctivitis. ^[1] More serious concerns may warrant emergency medical services (EMS) transport. Prehospital personnel, emergency physicians, and other medical personnel must be careful not to transmit this infection and should not overlook more serious comorbidity. Thorough hand washing, glove use, and using eye drops in individual or unit dose containers are necessary.

Treatment is often supportive. Artificial tears help the discomfort of keratitis and photophobia. Cold, moist compresses improve the swelling and discomfort of the lids. Antibiotic drops help prevent a secondary bacterial infection. Reserve topical corticosteroids for use by an ophthalmologist when substantial inflammation is present and herpes simplex is excluded.

Broad-spectrum antibiotics, such as Ciloxan (ciprofloxacin), Zymar (gatifloxacin), or Ocuflox (ofloxacin), are good choices. Sulfacetamide is also acceptable. Aminoglycoside is toxic to epithelia and retards healing. Polytrim (trimethoprim/sulfamethoxazole) is a reasonable choice particularly in children.

Patients with gonorrheal infections, neonates with infections, and patients who are immunocompromised should be admitted for administration of intravenous antibiotics.

For treatment guidelines, see the American Academy of Ophthalmology's guidelines. ^[6]

Consultations

Consult with an ophthalmologist for all serious eye complaints. Simple conjunctivitis usually can be followed up by the patient's primary care provider. Discuss with an ophthalmologist solutions to questions or equivocal diagnosis. Neisserial conjunctivitis is an ocular emergency and should be viewed as an ocular finding of systemic disease. Ophthalmologic consultation is essential.

Transfer

Manage simple conjunctivitis in the ED. Transfer may be appropriate for patients with complications from chronic or gonococcal conjunctivitis when an ophthalmologist is unavailable.

Treatment with antimicrobials and symptomatic therapy is recommended for all patients initially presenting to the emergency department (ED) with simple conjunctivitis. Numerous topical antimicrobial agents may be used, including topical sulfacetamide, erythromycin, gentamicin, ciprofloxacin, gatifloxacin, or ofloxacin. Avoid neomycin-containing solutions because 8-15% of patients have hypersensitivity reactions. Instill drops every 2 hours. An ointment can be used at night or every 4-6 hours throughout the day.

Systemic antibiotics

Consider gonococcal conjunctivitis part of a systemic disease, thus requiring systemic treatment. Inpatient medical regimens include cefoxitin, ceftriaxone, cefotaxime, or spectinomycin. Treat all patients who have chlamydia with tetracycline, doxycycline, azithromycin, or erythromycin. Outpatient therapy is acceptable in less serious cases in which compliance can be ensured and includes intravenous ceftriaxone (50 mg/kg, not to exceed 1 g) followed by doxycycline 100 mg twice a day or erythromycin 500 mg qid. Identify and treat patients' sexualpartners.

Chlamydial conjunctivitis can be treated with doxycycline 100 mg twice a day for 10 days or azithromycin 1 g. Erythromycin can be used in pregnant patients and infants. Topical therapy with erythromycin also is recommended and may speed resolution. As with gonococcal infections, identify and treat patients' sexual partners.

Ophthalmic antibiotics

Ophthalmic antibiotics are used for infectious conjunctivitis. Therapy must cover all likely pathogens in the context of the clinical setting. However, when prescribing the antibiotic, the care provider must take into account that the incidence of methicillin-resistant Staphylococcus aureus (MRSA) has continued to increase in recent years.

The US Food and Drug Administration (FDA) approved besifloxacin for the treatment of bacterial conjunctivitis. ^[7] Clinical studies showed that patients randomized to besifloxacin ophthalmic suspension 0.6% experienced significantly higher rates of clinical resolution and microbial eradication than patients randomized to vehicle. Besifloxacin was found to be as effective and well tolerated as moxifloxacin ophthalmic solution 0.5%. ^[8] In addition, a study by Comstock et al also showed besifloxacin ophthalmic suspension 0.6% to be safe and effective for the treatment of bacterial conjunctivitis. ^[9]

Decongestants generally have vasoconstricting effects with the ability to control pruritus. Mast cell stabilizers inhibit degranulation of sensitized mast cells following exposure to specific antigens and can aid in controlling pruritus for seasonal allergies.

Nonsteroidal anti-inflammatory agents (NSAIDs) are used for the treatment of allergic conjunctivitis. Although most NSAIDs are used primarily for their anti-inflammatory effects, they are also effective analgesics and are useful for the relief of mild to moderate pruritus. Ketorolac 0.4% has also been shown as effective in treating allergic conjunctivitis. ^[10]

Refer patients to their primary care provider for follow-up in 2-3 days to ensure they are responding to treatment. Viral conjunctivitis is usually self-limited to 10-14 days, but symptoms may persist for as many as 6 weeks.

Prescribe one of the previously mentioned antibiotics for discharged patients. For copious ocular secretions, patients may use frequent saline irrigation or artificial tears. Avoid eye patching.

Educate the patient regarding careful and frequent hand washing being necessary to reduce transmission from one eye to the other in the patient and from contacts.

During birth, risk of transmission of Gonococcus, Streptococcus, or Chlamydia to the fetus exists. Obtain maternal cervical culture results, if indicated and/or available.

Risk of chlamydial pneumonia exists. Pneumonia can occur in 10-20% of infants with chlamydial conjunctivitis as many as 6 months later. Untreated chlamydial conjunctivitis in adults can lead to conjunctival scarring.

Any of the bacterial organisms that cause conjunctivitis, particularly in a premature infant, can lead to sepsis and death. Neonates are at risk for secondary meningitis, cellulitis, and septicemia, particularly if the conjunctivitis is caused by Escherichia coli, Staphylococcus aureus, or Haemophilus influenzae.

Clinicians should be able to recognize a gonococcal infection in someone with ocular and genitourinary symptoms. Penetration of the cornea can occur within 2 days in patients with untreated Neisseria gonorrhoeae.

Infections with N meningitidis may require systemic antibiotics to prevent meningitis.

Failure to recognize herpes simplex conjunctivitis and keratitis and prescribing corticosteroids, as well as failure to consider other causes in a patient with an acutely red eye (eg, iritis, uveitis, angle-closure glaucoma, ocular ischemic syndrome, penetrating or perforating ocular injury) are also potential pitfalls.