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What is The first sign of Vit A deficiency is : and explain in detail?
Modified classification WHO (Xerophthalmia) XN : Night blindness
XIA : Conjunctival xerosis XIB : Bitot’s spots
X2: Corneal xerosis
X3A : Corneal ulceration/keratomalacia less than 1/3rd corneal surface
X3B : Corneal ulceration/keratomalacia equal to or more than 1/3rd corneal surface XS : Corneal scar
XF : Xerophthalmia fundus.