The mucous membrane that covers the surface of the eyeball and the inside of the eyelids becomes inflamed when conjunctivitis occurs. It could be acute or ongoing. The majority of cases result from bacterial or viral infection, including gonococcal and chlamydial infections. Keratoconjunctivitis sicca, allergies, chemical irritants, and trauma are among more causes. Infectious conjunctivitis is typically spread by direct contact between infected fingers or objects and the affected eye or another individual. Additionally, contaminated eye drops or respiratory secretions may be used to disseminate it [2].

Classification

Viral Conjunctivitis: The most frequent cause of viral conjunctivitis is adenovirus. Sequential bilateral illness with profuse watery discharge and follicular conjunctivitis are typical symptoms. Infection is very contagious. Adenovirus types 8, 19, and 37 are typically responsible for epidemic keratoconjunctivitis, which may induce corneal subepithelial infiltrates to impair vision.

The immune-mediated keratitis develops after up to two weeks of the active viral conjunctivitis. Preauricular adenopathy, fever, pharyngitis, and infections with adenovirus types 3, 4, 7, and 11 are common symptoms (pharyngoconjunctival fever). Typically, the illness lasts 10 days. It's possible for enterovirus 70 or coxsackievirus A24 to be the cause of contagious acute hemorrhagic conjunctivitis. Herpes simplex virus (HSV)-caused viral conjunctivitis is often unilateral and may be accompanied by lid vesicles [3].

Bacterial Conjunctivitis

Staphylococci, especially methicillin-resistant S aureus (MRSA), streptococci, including Streptococcus pneumoniae, Haemophiles species, Pseudomonas, and Moraxella are the bacteria that are most frequently isolated in cases with bacterial conjunctivitis. Any of them could result in eyelid matting and purulent discharge. Mild pain and eyesight haziness are present. Examination of stained conjunctival scrapings and cultures is advised in severe (hyper purulent) cases, particularly to detect gonococcal infection that needs emergency treatment.

If left untreated, the illness usually has a self-limiting duration of 10–14 days. The majority of topical antibiotics speed up clinical recovery. No topical antibiotic has distinguished itself as being superior to another because this infection is often self-limited [4].

Gonococcal Conjunctivitis

Gonococcal conjunctivitis frequently results in copious purulent discharge and is typically contracted by contact with contaminated vaginal fluids. Because of the potential for corneal involvement to quickly result in perforation, it is an ophthalmologic emergency. A stained smear and discharge culture are required to confirm the diagnosis. A single 1-g dosage of intramuscular ceftriaxone with 1000 mg of oral azithromycin is necessary for systemic therapy.

Chlamydial Keratoconjunctivitis

• Trachoma: With an estimated 40 million cases and 1.2 million blind persons worldwide, trachoma is the most prevalent infectious cause of blindness. Childhood infections that recur often cause bilateral follicular conjunctivitis, epithelial keratitis, and vascularization of the cornea (pannus). In adulthood, tarsal conjunctival scarring (cicatrization) causes trichiasis, entropion, and subsequent central corneal scarring [5]

• Inclusion Conjunctivitis: After coming into contact with chlamydia-infected vaginal fluids, the eye becomes infected. Acute redness, drainage, and irritation mark the first stages of the illness. Upon examination, follicular conjunctivitis and moderate keratitis are visible. Preauricular lymph nodes are often palpable and non-tender. Usually, healing has no aftereffects

Immunologic testing or PCR on conjunctival samples might be used to quickly confirm the diagnosis. A single oral dose of 1 g of azithromycin is used for treatment. It is important to check every case for genital tract infections and other STDs [6].

Dry Eyes

A general term used to describe a state of tear film instability and related ocular and visual problems is "dry eye," which is a prevalent and chronic ailment. Dry eye affects more women than males and gets worse as people age. Aqueous tear loss (keratoconjunctivitis sicca) is caused by hypofunction of the lacrimal glands, which can be brought on by ageing, inherited conditions, systemic diseases (such Sjogren syndrome), or systemic medications.

Environmental variables (such as too much screen time or a windy environment) or abnormalities in the lipid component of the tear film, such as blepharitis, may contribute to excessive tear evaporation. Vitamin A insufficiency, conjunctival scarring from trachoma, Stevens-Johnson syndrome, mucous membrane pemphigoid, graft-versus-host disease, chemical burns, or topical medication toxicity can all contribute to mucin shortage [7].

Clinical Findings

Dryness, redness, a feeling of a foreign body, and erratic eyesight are some of the patient’s complaints. With photophobia, difficulty moving the lids, and increased mucus secretion, there is persistent, noticeable discomfort in severe instances. On slit lamp examination, there are frequently problems of tear film stability and decreased tear volume even if gross inspection frequently shows no abnormality. When things get worse, Fluorescein and Lissa mine green are used to stain injured corneal and conjunctival cells. When things are really bad, there is significant mucoid discharge, conjunctival injection, and loss of the proper luster and epithelial thickness of the cornea and conjunctiva fluorescein-stained keratopathy that could advance to be blunt, ulceration Using the Schirmer test to gauge the rate of tear aqueous component generation, may help out [4].

Treatment

• Artificial tear drops or ointments are effective treatments for aqueous deficit. The most straightforward treatments are sodium chloride physiologic (0.9 percent) or hypo-osmotic (0.45 percent) solutions, which can be administered as frequently as every half-hour but are typically only required three or four times per day

• The majority of the time, three or four times a day, artificial tear preparations are employed and are generally safe. Preservatives used in some preparations to keep them sterile, however, have the potential to be toxic and allergic and can cause ocular surface toxicity in users who use them frequently

• An inflammatory ocular surface disorder is known as dry eye. Therefore, periodic treatment with low potency corticosteroid drops may be necessary for illness modification

• Eye care specialists should check the intraocular pressure of every patient using topical corticosteroids.

• The effectiveness of corticosteroid-free anti-inflammatory eye drops like the integrin antagonist lifitegrast 5 percent and the calcineurin inhibitor cyclosporine 0.05 percent ophthalmic emulsion (Restasis) is not universally agreed upon. In extreme situations, canalicular plugs or cautery are used to occlude the lacrimal puncta [8].

In most cases of bacterial conjunctivitis, there is no need for treatment because the condition usually resolves on its own. However, conjunctivitis in contact lens users and conjunctivitis brought on by gonorrhoea or chlamydia should be treated with antibiotics. Viral conjunctivitis is treated with supportive care. Antihistamine and mast cell stabilizer therapy reduces allergic conjunctivitis 

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2. Bielory L, Friedlaender MH. "Allergic conjunctivitis." Immunology and Allergy Clinics of North America, vol. 28, no. 1, 2008, pp. 43–58.

3. Varu D.M. et al. "Conjunctivitis preferred practice pattern®." Ophthalmology, vol. 126, no. 1, 2019, pp. P94–169.

4. Gonzales J.A. et al. "Ocular clinical signs and diagnostic tests most compatible with keratoconjunctivitis sicca: a latent class approach." Cornea, vol. 39, no. 8, 2020, pp. 1013–1016.

5. Godwin W. et al. "Trachoma prevalence after discontinuation of mass azithromycin distribution." The Journal of Infectious Diseases, vol. 221, no. S5, 2020, pp. S519–S524.

6. Oldenburg C.E. et al. "Trachoma prevalence after discontinuation of mass azithromycin distribution." The Journal of Infectious Diseases, 2020.

7. Beck K.M. et al. "Ocular co-morbidities of atopic dermatitis. Part I: associated ocular diseases." American Journal of Clinical Dermatology, vol. 20, no. 6, 2019, pp. 797–805. Available from: https://link.springer.com/article/10. 1007/s40257-019-00455-5

8. De Paiva C.S. et al. "Topical cyclosporine A therapy for dry eye syndrome." Cochrane Database of Systematic Reviews, vol. 2019, no. 9, 2019.