Long known as the âsunshine vitaminâ because the body makes it when skin is exposed to sunlight, vitamin D might now be dubbed the âsuperstar vitamin,â judging by the amount of attention it has garnered of late from researchers and the general public.
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test. Vitamin B12 deficiency can be caused by many factors, one of which is pernicious anemia, a condition resulting in deficient production of intrinsic factor in the parietal cells of the stomach. Intrinsic factor is a protein that is needed to assist in the absorption of vitamin B12 into the small intestine.
This results in a reduced number of abnormally large RBCs and anemia. Laboratory Tests. Symptoms of anemia will usually be investigated initially with a complete blood count (CBC) and differential. In pernicious anemia, other causes of vitamin B12 deficiency, or folate deficiency, these usually reveal: 1  A low hemoglobin level. 2  Red cell indicesâthe mean corpuscular volume (MCV), which is the average size of RBCs, is high. 3  A blood smear will reveal RBCs that are abnormally large and oval-shaped.