Conjunctivitis is an inflammation or infection of the conjunctiva, the transparent membrane that lines the eyelid and covers the white part of the eyeball. It can be caused by various factors and is characterized by redness, itching, and tearing of the eyes. Here’s an overview:
Causes
- Viral Conjunctivitis: Often caused by adenoviruses; highly contagious.
- Bacterial Conjunctivitis: Caused by bacteria like Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae and Chlamydia trachomatis (ATSI)
- Allergic Conjunctivitis: Triggered by allergens such as pollen, dust mites, or animal dander.
- Irritant Conjunctivitis: Caused by irritants like chlorine (from swimming pools), smoke, or foreign bodies in the eye.
Diagnosis
- Clinical Examination: Redness, tearing, itching, and discharge are common signs. The pattern of discharge can often indicate the cause (watery in viral, thick and purulent in bacterial).
- Patient History: Recent exposure to allergens, sick contacts, or history of similar symptoms.
- Slit Lamp Examination: For a more detailed examination of the eye
- Swab Cultures: Rarely needed, but can be used in severe, recurrent, or unresponsive cases to identify the specific causative organism.
Differential Diagnosis
- Dry Eye Syndrome: Can cause redness and irritation.
- Uveitis: Inflammation of the middle layer of the eye; more painful than conjunctivitis.
- Keratitis: Inflammation or infection of the cornea, often with severe pain and visual changes ie herpes keratitis
- Blepharitis: Inflammation of the eyelids.
- Glaucoma: Acute angle-closure glaucoma can cause redness, but typically with severe pain and visual impairment.
Management
- Viral Conjunctivitis: Mostly self-limiting. Symptomatic treatment includes cold compresses and artificial tears. Good hygiene to prevent spread.
- Bacterial Conjunctivitis: Antibiotic eye drops such as chloramphenicol.
- Oral Azithromycin 1g stat is used for Chlamydia trachomatis
- Allergic Conjunctivitis: Antihistamine or anti-inflammatory eye drops, avoiding allergens.
- Irritant Conjunctivitis: Rinsing the eye with saline and avoiding the irritant.
Preventive Measures
- Hygiene: Frequent hand washing; avoid touching the eyes.
- Avoid Sharing: Towels, cosmetics, or eye drops should not be shared.
- Allergy Management: Use air filters, keep windows closed during high pollen seasons, and regular cleaning to reduce allergens.
Referral
- Persistent or Severe Cases: If symptoms do not improve with initial treatment or if the vision is affected.
- Suspicion of Other Conditions: If other conditions like uveitis or keratitis are suspected, referral to an ophthalmologist is necessary.
Conclusion
Conjunctivitis is a common eye condition that can usually be managed effectively in a general practice setting. Identifying the cause is key to appropriate treatment. While viral and allergic conjunctivitis are largely managed with supportive care, bacterial conjunctivitis requires antibiotic treatment. Good hygiene practices are essential in preventing the spread of infectious conjunctivitis.