3. VITAMIN A - METABOLISM
SI
TRANSPORTABSORPTION
chylomicrons
STORAGE
LIVER
RBP
4. FUNCTIONS
VISION IN LOW LIGHT ANTIOXIDANT
DEVELOPMENT
OF TEETH &
SKELETAL TISSUE
EPITHELIAL CELL DIFFERENTIATION MAINLY
MUCUS SECRETING CELLS
ENHANCING
IMMUNITY
5. CAUSES ????
• Prolonged INADEQUATE INTAKE of vitamin A.
• IMPAIRED ABSORPTION. This may occur in a variety of
illnesses, including:
• Coeliac disease.
• Crohn's disease.
• Giardiasis - an infection of the gut (bowel).
• Cystic fibrosis-Diseases affecting the pancreas.
• Obstruction of the flow of bile from liver and gallbladder
into gut.
6.
7. SQUAMOUS METAPLASIA
Vitamin A deficiency can lead to
replacement of lining of upper respiratory
passage & urinary tract by keratinizing
squamous cells.
Loss of mucociliary epithelium of the airway
predisposes affected patients to pulmonary
infection.