Types of pink eye, the 3 types of conjunctivitis and differential conjunctivitis symptoms

Types of conjunctivitis/pink eye

Conjunctivitis in simple terms is called Pink eye. Pink eye is the common name for conjunctivitis, which is an inflammation or infection of the eye’s conjunctiva. 

Viruses are the most common cause of contagious conjunctivitis, but it is often also caused by bacteria. If certain viruses or bacteria enter the eye, conjunctivitis can develop. It can also develop if a person has a virus or bacterial infection that works its way through the body to the eyes. The viral and bacterial forms are very contagious and spread extremely easily.

An eye doctor can tell you if your symptoms are from “pink eye” or another type of conjunctivitis. If you do have pink eye, they may prescribe antibiotics, if necessary, or tell you how to ease your symptoms at home.

This article discusses types of conjunctivitis and differential diagnosis of different type of conjunctivitis.

See other eye diseases

Types of conjunctivitis

clinical definition of conjunctivitis is Inflammation of the conjunctiva (conjunctivitis) is classically defined as conjunctival hyperaemia associated with a discharge which may be watery, mucoid, mucopurulent or purulent.

Generally conjunctivitis is grouped into 3 types- Bacterial, viral and allergic conjunctivitis

Some varieties of conjunctivitis can be dangerous if not treated. There are numerous additional types of eye diseases that resemble pink eye.

Symptoms of bacterial conjunctivitis

Discomfort, foreign body, grittiness, blurring and redness of sudden onset (due to engorgement of vessels) are the usual presenting symptoms.
• Mild photophobia, i.e., difficulty to tolerate light.
• Mucopurulent discharge from the eyes.
• Sticking together of lid margins with discharge during sleep.
• Slight blurring of vision due to mucous flakes in front of cornea.
• Coloured halos, may be complained by some patients due to prismatic effect of mucus present on cornea.

Signs of bacterial conjunctivitis

• Flakes of mucopus seen in the fornices, canthi and lid margins is a critical sign.
• Conjunctival congestion, which is more marked in palpebral conjunctiva, fornices and peripheral part of bulbar conjunctiva, giving the appearance of ‘fiery red eye’. The congestion is typically less marked in circumcorneal zone.
• Chemosis, i.e., swelling of conjunctiva.
• Papillae of fine type may be seen.
• Petechial haemorrhages are seen when the causative organism is Pneumococcus.
• Cilia are usually matted together with yellow crusts.
• Eyelids may be slightly oedematous.

Viral conjunctivitis

Most of the viral infections tend to affect the epithelium, both of the conjunctiva and cornea; so,the typical viral lesion is a ‘keratoconjunctivitis’. In some viral infections, conjunctival involvement is more prominent (e.g., pharyngoconjunctival fever), while in others cornea is more involved (e.g., herpes simplex).

Types of acute viral conjunctivitis include:
• Acute follicular conjunctivitis, and
• Acute haemorrhagic conjunctivitis.

Symptoms of Viral conjunctivitis:
• Redness of sudden onset associated with watering, usually profuse, with mild mucoid discharge,
• Ocular discomfort

Allergic conjunctivitis

Any allergens that cause a reaction in the eyes can lead to allergic conjunctivitis. If your allergies inflame the conjunctiva of your eyes (making them red, swollen and extra itchy), they have caused allergic conjunctivitis. Many common allergens like pollen, dust and animal dander often lead to this condition. It can be seasonal (pollen), or it can flare up year round (dust; pet dander). Thankfully, allergic conjunctivitis is not contagious.

Types of conjunctivitis in clinical terms

Common types of conjunctivitis include:
A. Infective conjunctivitis

1. Bacterial conjunctivitis
   • Acute bacterial conjunctivitis
   • Hyperacute bacterial conjunctivitis
   • Chronic bacterial conjunctivitis
   • Angular bacterial conjunctivitis
2. Chlamydial conjunctivitis
   • Trachoma
   • Adult inclusion conjunctivitis
   • Neonatal chlamydial conjunctivitis
3. Viral conjunctivitis
   • Adenovirus conjunctivitis
   –– Epidemic keratoconjunctivitis
   –– Pharyngoconjunctival fever
   • Enterovirus conjunctivitis
   • Molluscum contagiosum conjunctivitis
   • Herpes simplex conjunctivitis
4. Ophthalmia neonatorum (A separate entity)
5. Granulomatous conjunctivitis
   • Parinaud oculoglandular syndrome
   B. Allergic Conjunctivitis
6. Simplex allergic conjunctivitis
   • Hay fever conjunctivitis (rhino conjunctivitis)
   • Seasonal allergic conjunctivitis (SAC)
   • Perennial allergic conjunctivitis (PAC)
7. Vernal keratoconjunctivitis (VKC)
8. Atopic keratoconjunctivitis
9. Giant papillary conjunctivitis (GPC)
10. Phlyctenular conjunctivitis (PKC)
11. Contact dermoconjunctivitis (drop conjunctivitis)
    C. Cicatricial conjunctivitis
    • Ocular mucous membrane pemphigoid (OMMP),
    • Stevens Johnson syndrome (SJS),
    • Toxic epidermal necrolysis (TeN), and
    • Secondary cicatricial conjunctivitis.

Ref : AK Khurana