Ophthalmology · Infectious Conjunctivitis
The facts most likely to be tested
Adenovirus is the most common viral pathogen causing acute conjunctivitis, frequently presenting with watery discharge and bilateral involvement.
Patients typically present with a foreign body sensation, erythema, and preauricular lymphadenopathy.
Epidemic keratoconjunctivitis is a severe form of adenoviral infection characterized by corneal subepithelial infiltrates and photophobia.
Viral conjunctivitis is highly contagious and spreads primarily through direct contact with ocular secretions or contaminated surfaces.
Physical examination reveals follicular conjunctivitis, which appears as small, elevated, translucent bumps on the palpebral conjunctiva.
Management is strictly supportive with cool compresses and artificial tears, as antibiotics are ineffective and unnecessary.
Patients should be advised to practice strict hand hygiene and avoid sharing towels or pillows to prevent nosocomial or household transmission.
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A 24-year-old medical student presents to the urgent care clinic complaining of a 3-day history of bilateral eye redness, watery discharge, and a gritty foreign body sensation. He reports that several of his classmates have had similar symptoms over the past week. On physical examination, there is diffuse conjunctival injection, follicular changes on the inferior palpebral conjunctiva, and a palpable, tender preauricular lymph node. Visual acuity is 20/20 bilaterally, and the cornea is clear upon slit-lamp examination.
What is the most appropriate management for this patient?
Supportive care with cool compresses and artificial tears
The patient's presentation of bilateral watery discharge, follicular conjunctivitis, and preauricular lymphadenopathy is classic for adenoviral conjunctivitis, which requires only supportive care and strict hygiene precautions.
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Etiology / Epidemiology
Most common cause is Adenovirus; highly contagious via direct contact or respiratory droplets.
Clinical Manifestations
Presents with watery discharge, foreign body sensation, and preauricular lymphadenopathy.
Diagnosis
Primarily a clinical diagnosis; no routine lab testing required for typical cases.
Treatment
Management is supportive care (cool compresses, artificial tears); avoid topical antibiotics.
Prognosis
Self-limiting condition; usually resolves within 10–14 days.
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Epidemiology & Etiology
Viral conjunctivitis is the most frequent cause of 'pink eye' in adults. The most common pathogen is Adenovirus, often associated with swimming pools or upper respiratory infections. It is highly contagious, requiring strict hand hygiene to prevent spread.
Pertinent Anatomy
The conjunctiva is a thin, vascularized mucous membrane covering the sclera and inner eyelids. Inflammation leads to hyperemia and edema, which manifests as the classic red eye. The proximity to the lacrimal system explains the profuse tearing.
Pathophysiology
Viral inoculation of the ocular surface triggers an inflammatory cascade. This results in vasodilation, increased vascular permeability, and the recruitment of mononuclear cells. The process is self-limiting as the host immune system clears the viral load.
Clinical Manifestations
Patients report watery discharge, burning, and a foreign body sensation. Look for preauricular lymphadenopathy and follicular conjunctivitis (small bumps on the palpebral conjunctiva). Red flags include vision loss, severe eye pain, or photophobia, which suggest corneal involvement or uveitis.
Diagnosis
Diagnosis is clinical. If the presentation is atypical or severe, a polymerase chain reaction (PCR) or viral culture can confirm the specific serotype. Slit-lamp examination may reveal punctate epithelial keratitis in advanced cases.
Treatment
Treatment is supportive care with cool compresses and artificial tears for symptomatic relief. Antihistamines may be used for pruritus. Do not use topical antibiotics as they are ineffective and increase resistance. Patients should be advised to avoid contact lenses and practice rigorous hand washing.
Prognosis
The condition is self-limiting, typically resolving within 10–14 days. Complications are rare but include subepithelial infiltrates that may cause transient visual disturbances. Patients should be monitored for worsening pain or vision changes.
Differential Diagnosis
Bacterial Conjunctivitis: Purulent discharge and matted eyelids
Allergic Conjunctivitis: Intense pruritus and bilateral involvement
Keratitis: Significant pain and photophobia
Uveitis: Ciliary flush and constricted pupil
Dacryocystitis: Tenderness and swelling over the lacrimal sac