Conjunctivitis
Overview
Plain-Language Overview
Conjunctivitis is an inflammation of the thin, clear tissue covering the white part of the eye and the inside of the eyelids, called the conjunctiva. It affects the eye's surface and can cause symptoms like redness, itching, and discharge. This condition can be caused by infections, allergies, or irritants. It often leads to discomfort and can affect vision temporarily if discharge or swelling is significant. The condition is common and can affect people of all ages. It primarily impacts the ocular system and can be contagious depending on the cause.
Clinical Definition
Conjunctivitis is defined as inflammation of the conjunctiva, typically caused by infectious agents such as bacteria (e.g., Staphylococcus aureus, Haemophilus influenzae), viruses (e.g., adenovirus), or noninfectious causes like allergens or irritants. The core pathology involves conjunctival hyperemia, edema, and increased mucus or purulent discharge. It is clinically significant due to its high prevalence, potential for contagion, and impact on patient comfort and vision. The condition is classified into bacterial, viral, allergic, and chemical types based on etiology. Diagnosis relies on clinical presentation and history, with bacterial forms often showing purulent discharge and viral forms associated with watery discharge and systemic viral symptoms. Allergic conjunctivitis is characterized by intense itching and bilateral involvement.