Which of the following is a finding in vitamin A deficiency?

• A. Decreased proprioception
• B. Hair loss
• C. Night blindness
• D. Bleeding

Answer: (C)

Vitamin A deficiency disrupts the visual cycle in rod photoreceptors, so night vision is reduced because rhodopsin can’t be regenerated efficiently in low light. Retinol from vitamin A is converted to retinal, a key component of rhodopsin; without enough retinoid, rods don’t respond well to dim light, leading to nyctalopia (night blindness). As deficiency progresses, surface eye changes like dryness and Bitot spots can occur, and more severe deficiency can cause corneal damage. The other options don’t fit this pattern: decreased proprioception points to neuropathy, hair loss can occur with other deficiencies or conditions, and bleeding is more typical of coagulation or vascular issues not specific to vitamin A deficiency.