American Board of Surgery Qualifying Exam (ABS QE) Practice Test

What is the outcome of corneal degeneration in vitamin A deficiency?

1. Keratomalacia

2. Xerosis cutis

3. Night blindness

4. Demyelination

The correct answer is: Keratomalacia

The outcome of corneal degeneration in vitamin A deficiency is keratomalacia, which is characterized by softening and clouding of the cornea. This condition occurs because vitamin A is crucial for the maintenance of epithelial and mucosal tissues, including those of the eyes. Inadequate vitamin A leads to changes in the corneal epithelium, making it more susceptible to damage and degeneration. This ultimately results in keratomalacia, a severe manifestation of vitamin A deficiency that can lead to blindness if not addressed promptly. The other choices do not directly relate to the specific outcome of corneal degeneration from vitamin A deficiency. Xerosis cutis refers to dry skin, which, while related to vitamin A deficiency, does not describe corneal changes. Night blindness is a visual impairment due to the inability to adjust to low light conditions, also related to vitamin A deficiency, but it does not specifically address corneal degeneration. Demyelination pertains to nerve loss and is unrelated to the effects of vitamin A deficiency on the cornea. Hence, keratomalacia is the clear and direct consequence of corneal degeneration related to a lack of vitamin A.