Conjunctivitis

Acute membranous conjunctivitis:

• It is an acute inflammation of the conjunctiva, characterized by formation of a true membrane on the conjunctiva. 
• The disease is typically caused by Corynebacterium diphtheriae. 
• This organism produces a violent inflammation of the conjunctiva, associated with deposition of fibrinous exudate on the surface as well as in the substance of the conjunctiva resulting in formation of a thick, grey-yellow membrane. 
• The membrane is tough and firmly adherent to the conjunctiva, which on removing bleeds and leaves behind a raw area. 

Significant eye pain or decreased visual acuity is not consistent with the diagnosis of viral conjunctivitis. The hallmark of bacterial conjunctivitis is a continuous globular purulent discharge seen at the lid margins and in the corners of the eye. Viral conjunctivitis typically has a clear discharge with occasional scant mucoid discharge. Both may present with a history of the eye “matted shut” in the morning.

D. i.e. Papilloma virus

D i.e. Vernal Keratoconjunctivitis

Ans. Both of the above

Ans. Staphylococcus aureus

Ans., Chlamydia trachomatis

Ans. Allergens are endogenous as well as exogenous

Ans. Adenovirus

Ans. Chlamydia

Ans. Membranous conjunctivitis

Ans. Foreign body retained is the fornix

Ans. Present only in infants

Ans. None

Ans. Aspergillus

Ans. A: CMV

Conjunctivitis can be classified as infectious or noninfectious.

Infectious conjunctivitis (pinkeye) accounts for 70 percent of all cases and is caused by either a bacteria (usually staphylococci, pneumococci, streptococci or chlamydia trachomatis) or a virus.

Bacterial conjunctivitis occurs in 50 percent of all cases, and viral conjunctivitis occurs in 20 percent. Infectious conjunctivitis is very contagious.

Noninfectious conjunctivitis (which accounts for the remaining 30 percent of all cases), can be caused by allergies (such as pollen or grass), chemicals (such as air pollutants, smoke or household cleaners), or underlying diseases (such as rheumatoid arthritis, lupus, Kawasaki’s disease, ulcerative colitis or Crohn’s disease).

Additionally, conjunctivitis can be caused by hemorrhaging from trauma or changes in pressure within the head (subconjunctival hemorrhage).

Viral causes of conjunctivitis:

• Herpes simplex
• Adenovirus
• Picornavirus (Coxsackie virus,enterovirus 70)
• Myxovirus (measles)
• Paramyxoviruses (mumps, Newcastle conjunctivitis)
• Molluscum contagiosum

Ans. is ‘a’ i.e., Enterovirus 70

Acute hemorrhagic conjunctivitis (AHC) may be caused by adenoviruses, but two enteroviruses, enterovirus 70 and coxsackie A24 variant, are the major causes

Ans. is ‘c’ Type II hypersensitivity

Phlyctenular keratoconjunctivitis

• Phlyctenular conjunctivitis is an allergic response of the conjunctival and corneal epithelium to some endogenous allergens and characterized by formation of the phlyctens. Phlyctens are grey, yellow or pinkish white nodules slightly raised above the surface, are seen on the bulbar conjunctiva, generally near the limbus. Peak age group is 3-15 years with slight female preponderance.

Etiology

• It is believed to be a delayed hypersensitivity (Type IV cell mediated) response to endogenous microbial proteins. Causative allergens are : – i) Staphylococcus proteins (most common); ii) Tuberculous proteins iii) Proteins of Moraxella axenfeld bacillus and certain parasites.

Symptoms

• Disease is usually unilateral (in contrast to vernal keratoconjunctivitis which is bilateral). There is mild irritation, discomfort and lacrimation. Itching is not prominent as seen in vernal keratoconjunctivitis.
• Phlyctens are pinkish white nodules at limbus. Phlyctens are surrounded by hyperamia (congestion) and this congestion of vessels is limited to the area around phlyctens. Phlyctens ulcerate at apex.
• Corneal involvement may result in miliary ulcer, ring ulcer, fascicular ulcer or sacrofulous ulcer. There may be diffuse infiltrative phlyctenular keratitis.

Treatment

• Topical steroids are the DOC.

Ans. is ‘a’ i.e., Corneal opacity

Vernal kerato conjunctivitis (spring cattarrh)

• Spring cattarrh is an allergic inflammation of conjunctiva which is characterized by recurrent, bilateral, inter‑stitial, selflimiting conjunctivitis that becomes aggravated during spring and summer period.
• It is considered to be Type I hypersensitivity reaction (immediate type) to exogenous allergens such as grass pollens.
• It is more common in boys and affects age group 4-20 years.
• More common in summer, hence the name spring catarrh looks a misnomer.
• Recently it is being labeled as “Warm weather conjunctivitis”.

Clinical features of spring catarrh

• Spring catarrh is characterized by marked itching & burning, Stringy (ropy) discharge, lacrimation, photo-phobia and heaviness of lids.
• Clinically spring catarrh is divided into three types : ‑

1. Palpebral form : – It is the most common types. The upper palpebral conjunctiva shows papillae (papillary hypertrophy with their characteristic appearance : – i) Lage & flat toped, ii) Cobble stone appearance (Pavement stone appearance). These papilla heal without scarring.
2. Bulbar form : – It is characterized by (i) Dusky red triangular congestion of bulbar conjunctiva in palpebral area; ii) Gelatinous thickened accumulation of tissue around the limbus; iii) Presence of discrete whitish raised dots along the limbus (Tranta’s spot).
3. Mixed form : – Both bulbar and palpebral manifestations occur together.

Corneal signs (Vernal keratopathy)

• Punctate epithelial keratitis
• Ulcerative vernal keratitis : shallow transverse ulcer (Shield ulcer)
• Vernal corneal plaques
• Subepithelial scarring
• Pseudogerontoxon: chracterized by a classical “cupid’s bow” outline.

Ans. c. Topical antibiotics are the mainstay of treatment

Ans. is ‘a’ i.e., Moraxella 

Angular conjunctivitis

• It is a type of chronic conjunctivitis characterized by mild grade inflammation confined to conjunctiva and lid margins near the angles associated with maceration of the surrounding skin.
• Moraxella axenfeld (Moraxella lacunata), a diplobacillus, is the commonest causative organism. o Less commonly, staphylococcus aureus can also cause angular conjunctivitis.
• Angular conjunctivitis responds to tetracycline ointment.
• Eye drops containing zinc inhibit the proteolytic ferment and are of great value although less rapidly effective, and may be used in addition to tetracycline.

Ans. is ‘a’ i.e., Trachoma 

Adult inclusion conjunctivitis

• It is a type of follicular conjunctivitis caused by serotypes D to K of chlamydia trachomatis-in sexually active young adults.
• The primary source of infection is urethritis in males and cervicitis in females.
• Transmission may occur either through contaminated fingers or through contaminated water of swimming pools (Swimming pool granuloma).
• Presentation is similar to other acute follicular conjunctivits with mucopurulent discharge. 
• The disease runs a benign course and often evolves into the chronic follicular conjunctivitis.

Ans. is ‘b’ i.e., Staphylococcus

Phlyctenular keratoconjunctivitis

• Phlyctenular conjunctivitis is an allergic response of the conjunctival and corneal epithelium to some endogenous allergens and characterized by formation of the phlyctens. Phlyctens are grey, yellow or pinkish white nodules slightly raised above the surface, are seen on the bulbar conjunctiva, generally near the limbus. Peak age group is 3-15 years with slight female preponderance.