Both trachoma and AIC present clinically as conjunctivitis characterized by small lymphoid follicles in the conjunctiva, although trachoma usually starts insidiously before 2 years of age.

• With progression of trachoma, there is inflammatory leukocytic infiltration and superficial vascularization (pannus formation) of the cornea.
  • - Scarring eventually distorts the eyelids, turning lashes inward and abrading the eyeball (trichiasis and entropion).
  • - The corneal epithelium eventually ulcerates, with subsequent scarring and blindness.
  • - Destruction of goblet cells, lacrimal ducts, and glands causes dry-eye syndrome (xerosis), with resultant corneal opacity and secondary bacterial corneal ulcers.
• AIC is an acute unilateral follicular conjunctivitis with preauricular lymphadenopathy and presents similarly to acute conjunctivitis due to adenovirus or HSV.
  • - Corneal inflammation is evidenced by discrete opacities, punctate epithelial erosions, and superficial corneal vascularization.
  • - Left untreated, the disease may persist for 6 weeks to 2 years.