Author- Dr. Mohammad Shamim, MD
Conjunctivitis, commonly referred to as “pink eye,” is the inflammation of the conjunctiva, the transparent membrane covering the white part of the eyeball and the inner eyelid. It can be caused by infections, allergens, irritants, or underlying diseases.
Causes Of Conjunctivitis
Infectious Conjunctivitis:
- Viral Conjunctivitis: Predominantly caused by adenoviruses, it can also be associated with herpes simplex virus (HSV), varicella-zoster virus (VZV), and others. Highly contagious and often spread through direct or indirect contact with the eye secretions of an infected person.
- Bacterial Conjunctivitis: Common pathogens include Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. More severe forms can be caused by Neisseria gonorrhoeae and Chlamydia trachomatis.
Non-infectious Conjunctivitis:
- Allergic Conjunctivitis: Triggered by allergens such as pollen, dust mites, pet dander, molds, and environmental pollutants. Can be seasonal (hay fever) or perennial.
- Chemical Conjunctivitis: Due to exposure to irritants such as chlorine, smoke, industrial pollutants, or personal care products.
- Other Causes: Autoimmune diseases (like rheumatoid arthritis or systemic lupus erythematosus), underlying systemic infections, or foreign bodies in the eye.
Symptoms Of Conjunctivitis
- Redness in the sclera or inner eyelid
- Increased tear production
- Thick yellow or greenish discharge, especially in bacterial conjunctivitis
- Itchiness, particularly in allergic conjunctivitis
- Gritty feeling in the eye
- Crusting of eyelids or lashes, especially after sleep
- Blurred vision and light sensitivity in more severe cases
Diagnosis Of Conjunctivitis
- History and Physical Examination: Detailed patient history including onset, duration, and associated symptoms, coupled with a thorough eye examination.
- Laboratory Tests:
- Swab Cultures: For bacterial and viral identification.
- PCR Tests: For detecting specific viral pathogens.
- Allergy Tests: Skin prick tests or serum IgE levels for suspected allergic conjunctivitis.
Management
Viral Conjunctivitis
- Symptomatic Treatment:
- Cool Compresses: To reduce swelling and discomfort.
- Artificial Tears: To lubricate the eyes and provide relief from dryness and irritation.
- Antiviral Medications: For severe cases caused by herpes simplex virus (e.g., acyclovir, ganciclovir).
- Hygiene Measures:
- Avoid sharing personal items (towels, pillows).
- Frequent handwashing and avoiding touching the eyes.
- Isolation from school or work to prevent spread.
Bacterial Conjunctivitis
- Antibiotic Eye Drops or Ointments:
- First-line: Erythromycin ointment, trimethoprim-polymyxin B drops.
- Alternative Options: Fluoroquinolone drops (ciprofloxacin, ofloxacin), especially for contact lens wearers.
- Severe Cases: Systemic antibiotics for Neisseria gonorrhoeae or Chlamydia trachomatis infections (e.g., ceftriaxone, azithromycin).
- Hygiene Measures: Similar to those for viral conjunctivitis.
Allergic Conjunctivitis
- Avoidance of Allergens: Identifying and minimizing exposure to triggers.
- Pharmacological Treatments:
- Antihistamine Drops: Olopatadine, ketotifen.
- Mast Cell Stabilizers: Cromolyn sodium, nedocromil.
- Combined Antihistamine/Mast Cell Stabilizer Drops: For dual action.
- Corticosteroid Drops: Loteprednol, for short-term use in severe cases.
- Oral Antihistamines: Cetirizine, loratadine for systemic relief.
Chemical Conjunctivitis
- Immediate Irrigation: Rinse eyes with saline or water for at least 15 minutes.
- Avoidance of Irritants: Identifying and avoiding the chemical irritant.
- Symptomatic Treatment: Artificial tears and cold compresses for relief.
- Medical Attention: Especially for severe chemical burns or persistent symptoms.
Prevention
- Hand Hygiene: Regular and thorough handwashing.
- Disinfecting Contact Lenses: Proper cleaning and storage of contact lenses.
- Avoid Sharing Personal Items: Towels, makeup, and eye drops.
- Protective Eyewear: Use of goggles in environments with potential eye irritants.
Complications
- Chronic Conjunctivitis: Persistent inflammation requiring long-term treatment.
- Keratitis: Inflammation of the cornea, leading to pain and vision problems.
- Corneal Ulcers: Open sores on the cornea, particularly in severe bacterial infections.
- Vision Impairment: Rare, but possible if the cornea is significantly affected.
Prognosis
- Generally Favorable: Most cases resolve without long-term effects with appropriate treatment.
- Monitoring Required: For complications, especially in severe or untreated cases.
Conclusion
In summary, conjunctivitis is a common eye condition with various causes and presentations. Effective management involves accurate diagnosis, targeted treatment, and preventive measures to control spread and prevent complications. Pharmacological treatments vary based on the etiology, and patient education on hygiene and avoidance of irritants is crucial for recovery and prevention.
References
- Harrison’s Principle of Internal Medicine.
- Current Medical Diagnosis And Treatment.