Conjunctivitis, also known as pink eye, is inflammation of the outermost layer of the eye and the inner surface of the eyelid. It makes the eye appear pink or reddish. Classification of conjunctivitis -Based onset- Acute Sub acute ChronicBased on type of Exudate Serous Catarrhal Purulent Mucopurulent Membranous PseudomembranousBased on conjunctival response Follicular Papillary Granulomatous Based on Etiology a) Infectious -1. Bacterial conjunctivitis• Acute bacterial conjunctivitis• Hyperacute bacterial conjunctivitis• Chronic bacterial conjunctivitis• Angular bacterial conjunctivitis2. Chlamydial conjunctivitis• Trachoma• Adult inclusion conjunctivitis• Neonatal chlamydial conjunctivitis3. Viral conjunctivitis • Adenovirus conjunctivitis• Enterovirus conjunctivitis• Molluscum contagiosum conjunctivitis• Herpes simplex conjunctivitis 4.Ophthalmia Neonatorum 5.Granulomatous conjunctivitisNon infectious a) Allergic conjunctivitis-• Simple allergic conjunctivitis• Vernal keratoconjunctivitis• Atopic keratoconjunctivitis• Giant papillary conjunctivitis• Phlyctenular conjunctivitis• Contact dermatoconjunctivitisb)Cicatricial conjunctivitis• Ocular mucous membrane pemphigoid• Steven Johnson syndrome• Toxic epidermal necrolysis• Secondary cicatricial conjunctivitisc)Toxic conjunctivitisAcute conjunctivitis- (resolving in less than 4 weeks ) may be classified based on type of discharge (mucoid or mucopurulent),conjunctival reaction (follicular or papillary) or aetiology (bacterial,viral,chlamydial or fungal)Chronic conjunctivitis-(of more than 4 weeks)- includes inflammatory conjunctivitis, angular conjunctivitis ,trachoma & granulomatous conjunctivitis Acute Bacterial conjunctivitis—In developing country it is the most common type of conjunctivitis. It can occur as sporadic & epidemics cases. It quite frequent during monsoon season.Etiology-a) Predisposing factors-• Flies • Poor hygienic conditions• Hot dry climate• Poor sanitation• Dirty habbitsb) Causative organism• Staphylococcus aureus• Staphylococcus epidermis• Streptococcus pneumonia• Streptococcus pyogenes• Haemophilus influenza• Moraxella lacunate• Pseudomonas pyocyanea• Neisseria gonorrhoeae• Neisseria Meningitides• Corynebacterium diphtheriaMode of infection-a)Exogenous infection- Directly through close contact as air borne infections or as water borne infections Through vector transmission Through material transfer such as infected fingers of doctors,nurses,common towels ,handkerchiefs & infected tonometers.b)Local spread –from neighbouring structures such as infected lacrimal sac, lids,& nasopharynx.c)Endogenous infections –rarely through blood e.g.gonococcal & meningococcal infections.ACUTE BACTERIAL CONJUNCTIVITISIt is characterised by marked conjunctival hyperaemia & mucopurulent discharge from the eye .So also called as acute mucopurulent conjunctivitis.Common causative bacteria-Staphylococcus aureus , Koch- Weeks Bacillus, Pneumoccous & Streptococcus.Pathology- Pathological changes of bacterial conjunctivitis consists of Vascular Response- Congestion & increased permeability of the conjunctival vessels associated with proliferation of capillaries. Cellular Response- Exudation of polymorphonuclear cells and other inflammatory cells into the conjunctival sac. Conjunctival tissue Response- Conjunctiva becomes oedematous ,proliferation of basal layer of conjunctival epithelium and increase in the number of mucin secreating goblet cells. Conjunctival discharge- It consists of tears,mucus,inflammatory cells,desquamated epithelial cells,fibrin and bacteria. Clinical features-Symptoms –• Discomfort & foreign body sensation due to engorgement of vessels• Mild photophobia• Mucopurulent discharge from eyes• Sticking together of lid margin during sleep• Slight blurring of vision due to mucous flakes in front of cornea• Coloured halos due to prismatic effect of mucus present on corneaSigns-• Flakes of mucous seen in the fornices, canthi & lid margins .• Conjunctival congestion which is more marked in palpebral conjunctiva, fornices & peripheral part of bulbar conjunctiva,giving the appearance of “fiery red eye”.• Chemosis i.e swelling of conjunctiva• Papillae • Petechial haemorrhage are seen when the causative organism is pnumoccous• Cilia are usually matted together with yellow crusts• Eye lids-oedematousClinical course- 3-5 daysComplications –• Marginal corneal ulceration• Superficial keratitis• Blepharitis• Dacryocystitis• Chronic conjunctivitis TREATMENT - Topical antibiotics – chloramphenicol (1%) or Gentamycin (0.3%) or Tobramycin 0.3% ,Ofloxacin( 0.3%),Gatiflox (0.3%)3-4 hourly in day & ointment used at night. Irrigation of conjunctival sac with sterile warm saline once or twice a day will help by removing the deleterious material.Frequent eye wash contraindicated as it will wash away the lysozyme & other protective proteins present in the tears. Dark goggles to prevent the photophobia Anti -inflammatory & analgesic drugs may be given orally for 2-3 days to provide symptomatic relief from mild pain especially in sensitive patients. No bandage should be applied because after bandging the conjunctival sac is converted into an incubator & thus infection flares to a severe degree within 24 hours. Exposure to air keeps the temperature of conjunctival cul-de-sac low which inhibits the bacterial growth. No steroid should be applied ,otherwise infection will flare up and leads to bacterial corneal ulcer.PREVENTION- Don’t use the same eye cosmetics for infected and non infected eye Avoid sharing personal item like eye drops ,makeup ,towel ,bedding contact lenses and eye glasses. Wash your hand with sanitizers especially after contact with pink eye Avoid repeated touching or rubbing of infected eyes .This can worsen the condition and spread to other eyes Stop wearing contact lenses until the infection is persist.