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What is Phlyctenular conjunctivitis is caused by - and explain in detail?
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 and (iii) Proteins of Moraxells axenfeld bacillus and ceain parasistes. Reference : AK Khurana 7th edition page 85