Type IV hypersensitivity to Mycobacterium tuberculosis antigen may manifest as –: (A) Iridocylitis, (B) Polyarteritis nodosa, (C) Phlyctenular conjunctivitis, (D) Giant cell arteritis
Answer is C. Phlyctenular conjunctivitis is type IV hypersensitivity reaction to endogenous allergen (tubercular protein, staphylococcal protein).