This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
Phlyctenular conjunctivitis false is – 
Select and explain. 
A. The most common cause is tuberculosis, B. The lesions are typically found near the limbus, C. Predominantly affects children, D. Is a type IV hypersensitivity reaction
A: The most common cause is tuberculosis
Answer: A: The most common cause is tuberculosis 
Explanation: Phlyctenular conjunctivitis is a type IV hypersensitivity reaction to endogenous allergen.
Previously Tuberculous proteins were considered as the most common cause. Staphylococcal proteins are now thought to account for most of the cases.
Peak age group is 3 -15 years with slight female preponderance.
Phlyctens are seen on the bulbar conjunctiva, generally at or near the limbus.