Clinical features

The early stages:

• characterised by papillary hypertrophy, the development of lymphoid follicles, a punctate keratitis and pannus formation
• prominent featurs are pain, lacrimation and photophobia

Gradually:

• the follicles become more numerous and spread onto the bulbar conjunctiva
• there is progressive scarring of the upper lid, trichiasis and entropion
• the lower lid is less frequently affected.
• reinfection is common either by the original infective agent or due to a secondary bacterial infection. This contributes to the scarring, particularly of the cornea

Ultimately, blindness results.