An infant with diarrhea presents with impaired vision and multiple eye abnormalities. The clinician observes severe keratinization of conjunctiva and characteristic spots over it(as shown in the photograph) and suspects it to be a nutritional vitamin deficiency. False statement regarding this condition is ?

  1. a) These are Bitot’s spots.
  2. b) Keratomalacia is a potentially reversible condition and can be cured.
  3. c) Optic nerve impingement due to bony overgrowth may also occur.
  4. d) Manifestations usually occur after 2 years of age.

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One thought on “An infant with diarrhea presents with impaired vision and multiple eye abnormalities. The clinician observes severe keratinization of conjunctiva and characteristic spots over it(as shown in the photograph) and suspects it to be a nutritional vitamin deficiency. False statement regarding this condition is ?

  1. Correct answer is (B). Keratomalacia is a potentially reversible condition and can be cured.
    Exp.
    REF : Nelson 18th Ed. Chapter. 46.
    The most obvious symptoms of vitamin A deficiency are associated with the requirement of this vitamin for the maintenance of epithelial functions. In intestine, a normal, mucus-secreting epithelium is an effective barrier against a path ogenic attack that can cause diarrhea. Similarly, in the respiratory tract, a mucus-secreting epithelium is essential for the disposal of inhaled pathogens and toxicants. Epithelial changes in the respiratory system can result in bronchial obstruction. Characteristic changes due to vitamin A deficiency in the epithelia include a proliferation of basal cells, hyperkeratosis, and the formation of stratified, cornified squamous epithelium. Squamous metaplasia of the renal pelves, ureters, vaginal epithelium, and the pancreatic and salivary ducts may lead to increased infections in these areas. In the urinary bladder, loss of epithelial integrity may result in pyuria and hematuria. Epithelial changes in the skin due to vitamin A deficiency are manifested as dry, scaly, hyperkeratotic patches, commonly on the arms, legs, shoulders, and buttocks. The combination of defective epithelial barriers to infection, low immune response, and lowered response to inflammatory stress, all due to insufficient vitamin A, can cause poor growth and serious health problems in children. The most characteristic and specific signs of vitamin A deficiency are eye lesions. Lesions due to vitamin A deficiency develop insidiously and rarely occur before 2 yr of age. An early symptom is delayed adaptation to the dark; later when vitamin A deficiency is more advanced, it leads to night blindness due to the absence of retinal in the visual pigment, rhodopsin, of the retina. Photophobia is a common symptom. As vitamin A deficiency progresses, the epithelial tissues of the eye become severely altered.
    The cornea protects the eye from the environment and is also important in light refraction. In early vitamin A deficiency, the cornea keratinizes, becomes opaque, is susceptible to infection, and forms dry, scaly layers of cells (xerophthalmia). In later stages, infection occurs, lymphocytes infiltrate, and the cornea becomes wrinkled; it degenerates irreversibly (keratomalacia), resulting in blindness. The conjunctiva keratinizes and develops plaques (Bitot spots, it becomes dry (conjunctival xerosis), and the lacrimal glands keratinize. The pigment epithelium, the structural element of the retina, keratinizes. When it degenerates, the rods and cones have no support, so they break down and blindness results.. These eye lesions are primarily diseases of the young and are a major cause of blindness in developing countries. Other clinical signs of vitamin A deficiency may include poor overall growth, diarrhea, susceptibility to infections, anemia, apathy, mental retardation, and increased intracranial pressure with wide separation of the cranial bones at the sutures. There may be vision problems due to bone overgrowth causing pressure on the optic nerve.

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