Keratomalacia is seen in which of the following infections –
**Core Concept**
Keratomalacia is a severe form of vitamin A deficiency, leading to corneal softening and potentially irreversible blindness. It is often seen in conjunction with other signs of malnutrition, particularly in children in developing countries.
**Why the Correct Answer is Right**
Keratomalacia is primarily caused by a lack of retinol, the active form of vitamin A, which is essential for maintaining the integrity of the cornea. Vitamin A deficiency can occur due to inadequate dietary intake, impaired absorption, or increased requirements, such as during periods of rapid growth or in the presence of chronic infections. The cornea relies on vitamin A to maintain its epithelial barrier function and prevent water loss, and its deficiency can lead to corneal softening and ulcers. Infections such as measles, which is listed as the correct answer, can exacerbate vitamin A deficiency by increasing the body's demand for the vitamin and impairing its absorption.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a correct answer because while it may be related to eye diseases, it is not directly associated with keratomalacia.
**Option B:** This option is incorrect because it is not a recognized cause of keratomalacia.
**Option D:** This option is incorrect because while it may be related to eye diseases, it is not directly associated with keratomalacia.
**Clinical Pearl / High-Yield Fact**
In developing countries, vitamin A deficiency is a significant public health concern, and supplementation programs have been implemented to prevent its consequences, including keratomalacia.
**Correct Answer:** C. Measles