A acute conjunctivitis which involves a fibrin-rich exudate formation on the surface of the conjunctiva. Infectious causes of pseudomembranes include Corynebacterium diphtheriae, streptococci, pneumococci, herpes simplex virus, adenovirus, Chlamydia and gonococci. Other causes include chemical (alkali) irritants, erythema multiforme, and ocular pemphigoid.