Conjunctivitis overview and Definition

It is also called a Pink eye. It might result in the inflammation the conjunctiva. The conjunctiva is the thin clear tissue that lies over the white part of the eye and lines the inside of the eyelid.


When allergens enters the tear flim, it triggers the conjunctival mast cells that bear the IgE antibodies.

Calcium enters the cell

Degranulation of mast cells results in production of Histamine

Histamine release causes Vasodilatation and oedema and resulting reddishness and swelling of the eyes.

Allergic conjunctivitis:

  It is more common among the people who is already more prone to seasonal allergies. They develop it when they come into contact with a substance that triggers an allergic reaction in their eyes.

Giant papillary conjunctivitis:

It is a type of allergic conjunctivitis caused by the chronic presence of a foreign body in the eye. People who wear hard or rigid contact lenses, wear soft contact lenses that are not replaced frequently, have an exposed suture on the surface of the eye or have a prosthetic eye are more likely to develop this form of conjunctivitis.

Allergic conjunctivitis occurs more commonly among people who already have seasonal allergies. They develop it when they come into contact with a substance that triggers an allergic reaction in their eyes.

Giant papillary conjunctivitis is a type of allergic conjunctivitis caused by the chronic presence of a foreign body in the eye.

Bacterial conjunctivitis caused by staphylococcal or streptococcal bacteria from your own skin or respiratory system. Insects, physical contact with other people, poor hygiene (touching the eye with unclean hands), or using contaminated eye makeup and facial lotions can also cause the infection. Sharing makeup and wearing contact lenses that are not your own or are improperly cleaned can also cause bacterial conjunctivitis.


Viral conjunctivitis is most commonly caused by contagious viruses associated with the common cold. It can develop through exposure to the coughing or sneezing of someone with an upper respiratory tract infection. Viral conjunctivitis can also occur as the virus spreads along the body's own mucous membranes, which connect the lungs, throat, nose, tear ducts and conjunctiva. Since the tears drain into the nasal passageway, forceful nose blowing can cause a virus to move from your respiratory system to your eyes.

Ophthalmia neonatorum is a severe form of bacterial conjunctivitis that occurs in newborn babies. This is a serious condition that could lead to permanent eye damage if it is not treated immediately. Ophthalmia neonatorum occurs when an infant is exposed to chlamydia or gonorrhea while passing through the birth canal.

Chemical conjunctivitis

Chemical Conjunctivitis can be caused by irritants like air pollution, chlorine in swimming pools, and exposure to noxious chemicals.





Routes of Transmission

Conjunctivitis occurs by the exposure to contaminated air and water.  It also spreads by bare exposure of eye to environment.

Clinical signs & symptoms

  • the feeling that some irritants in the eye or some gritty sensation in the  eye
  • red eyes
  • burning eyes
  • itchy eyes
  • watery eyes
  • puffy eyelids
  • blurry hazy vision
  • being extra sensitive to light

lots of mucus, pus, or thick yellow discharge from the eyes. There can be so much that your eyelashes stick together (usually with bacterial conjunctivitis

Differential Diagnosis

  • Patient history to determine the symptoms, when the symptoms began, and whether any general health or environmental conditions are contributing to the problem.
  • Visual acuity measurements to determine whether vision has been affected.
  • Evaluation of the conjunctiva and external eye tissue using bright light and magnification.
  • Evaluation of the inner structures of the eye to ensure that no other tissues are affected by the condition.
  • Supplemental testing, which may include taking cultures or smears of conjunctival tissue. This is particularly important in cases of chronic conjunctivitis or when the condition is not responding to treatment.

Cytology scraping:

Ophthalmologist acquires the scraping from the conjunctiva and see those abnormalities using microscopy.

Polymerase chain reaction:

This is done by the amplification of the DNA of the infectious agents.

Direct fluoresecense monoclonal antibody test:

The smears obtained from the conjunctiva are stained and results are examined.



Conjunctivitis can resolve within 5-7 days in 65 % of cases.


  • Don't touch your eyes with your hands.
  • Wash your hands often.
  • Use a clean towel and washcloth daily.
  • Don't share towels or washcloths.
  • Change your pillowcases often.
  • Throw away your eye cosmetics, such as mascara.

Don't share eye cosmetics or personal eye care items