Inflammatory diseases of the conjunctiva can be divided into acute, subacute and chronic according to the condition and course of the disease; according to the etiology of the disease, it can be divided into bacterial, viral, chlamydial, fungal and allergic; according to the characteristics of the lesions of the conjunctiva, it can be divided into acute follicular conjunctivitis, chronic follicular conjunctivitis, membranous and pseudomembranous conjunctivitis and so on. Etiology The etiology of conjunctivitis can be categorized into infectious and non-infectious according to its different nature. Infectious Conjunctivitis due to infection by pathogenic microorganisms. Non-infectious allergic inflammation caused by local or systemic allergic reactions is the most common, and external physical and chemical factors, such as light and various chemical substances, can also be pathogenic factors. Clinical manifestations Conjunctival congestion and increased secretion are common features of various conjunctivitis, inflammation can be monocular or bilateral simultaneous/sequential onset. 1. Symptoms: foreign body sensation, burning sensation, heavy eyelids, increased secretion, photophobia, tearing and different degrees of vision loss when the cornea is involved. 2. Signs The signs of conjunctivitis are an important basis for the correct diagnosis of different kinds of conjunctivitis. (1) Conjunctival congestion Conjunctival vascular congestion is characterized by the more obvious congestion near the dome, with reticular distribution of blood vessels and bright red color, which may extend into the periphery of the cornea to form corneal vascular opacities. (2) Discharge Purulent discharge is usually seen in gonococcal conjunctivitis; mucosal purulent or catarrhal discharge is usually seen in bacterial or chlamydial conjunctivitis, which often adheres firmly to the eyelashes, making it difficult to open the eyelids in the morning; watery discharge is usually seen in viral conjunctivitis. (3) Conjunctival edema Conjunctival vasodilatation and exudation caused by conjunctival inflammation leads to tissue edema, due to the bulbar conjunctiva and the dome of the conjunctiva tissue relaxation, edema bulge obvious. (4) Subconjunctival hemorrhage Mostly in the form of dots or small flakes, virus-induced epidemic hemorrhagic conjunctivitis can often be accompanied by subconjunctival hemorrhage. (5) Papillae are nonspecific signs of conjunctival inflammation and may be located on the lid conjunctiva or corneal limbus, presenting as an elevated, polygonal mosaic-like appearance, with areas of congestion separated by pale furrows. (6) Follicles Follicles are yellowish-white, smooth, rounded elevations, 0.5-2.0 mm in diameter, but in some cases, such as chlamydial conjunctivitis, larger follicles may also be present; viral conjunctivitis and chlamydial conjunctivitis are often referred to as acute follicular conjunctivitis or chronic follicular conjunctivitis because of the obvious follicular formation that accompanies them. (7) Membrane and pseudomembrane Membrane is attached to the conjunctival surface of the cellulose exudate, pseudomembrane is easy to peel, while the true membrane is not easy to separate, forcible peeling trauma bleeding, the essential difference between the two lies in the degree of inflammatory response, the true membrane of the inflammatory reaction is more intense, diphtheria bacillus cause severe membranous conjunctivitis; β-hemolytic streptococcus, pneumococcus, gonococcus, adenovirus, inclusion bodies, etc., can cause membranous or pseudomembranous Conjunctivitis. (8) Scarring Damage to the stromal tissue is the histologic basis for conjunctival scarring. Early signs of conjunctival scarring include narrowing of the conjunctival vault and subepithelial fibrosis of the conjunctiva. (9) Preauricular lymph node enlargement Viral conjunctivitis is often associated with preauricular lymph node enlargement. (10) Pseudo-ptosis Mild ptosis due to hypertrophy of the upper eyelid tissues by cellular infiltration or scar formation, mostly seen in the late stage of trachoma. (11) Conjunctival granuloma is rare, but can be seen in chronic inflammation caused by tuberculosis, leprosy, syphilis and rickettsiae. Treatment 1. Local treatment (1) Rinse the conjunctival sac. Its function is mainly to clean, commonly used for saline, 2%~3% trehalose solution or 1:5000~1:10,000 liters of mercury (or potassium permanganate) solution. (2) Don’t cover the affected eye because there is a lot of secretion in conjunctivitis, if the affected eye is covered, the secretion is not easy to be discharged and collects in the conjunctival sac; and the temperature of the conjunctival sac will increase after covering, which is more conducive to the propagation of bacteria and aggravate the conjunctivitis. (3) Topical medication Antibacterial drugs or antiviral eye drops. According to the pathologic diagnosis, choose the appropriate therapeutic drugs. Available 0.5% ~ 1% silver nitrate, eye drops to turn the eyelid, the eye drops on the lid conjunctiva, drops after a moment of pause, that is, with saline rinse. Or use a cotton swab dipped in a small amount of liquid, applied to the surface of the lid conjunctiva, followed by saline rinse. 2. Systemic treatment For severe conjunctivitis, such as gonococcal conjunctivitis, it is necessary to combine with systemic medication. Prevention Conjunctivitis is mostly a contact infection, so we should advocate washing hands frequently and avoiding rubbing the eyes. Wash your face with running water, and keep towels and handkerchiefs separate from others, and clean and disinfect them frequently. Patients with infectious conjunctivitis should be isolated and not allowed to swim in public swimming areas. If one eye suffers from conjunctivitis, the patient must be told to protect the healthy eye from infection. Anyone who works in a windy, dusty, smoky or other irritating environment should improve the environment and wear protective glasses to prevent conjunctivitis.