Pathology - Megaloblastic Anemia

Pathology - Megaloblastic Anemia 
Etiology 
Vitamin B deficiency anemia, also known as pernicious anemia, can be caused by autoimmune gastritis, which leads to the inability to make intrinsic factor. Other causes include malabsorption due to dietary factors such as a vegetarian diet, as well as surgical procedures like gastric resection or resection of the ileum. 

Folate deficiency anemia can be caused by malabsorption or a lack of folate in the diet. This condition is commonly observed in individuals who consume excessive amounts of alcohol, as well as pregnant women and those on certain medications such as methotrexate, sulfa medicines, phenytoin, or AZT. 

Pathology 
Vitamin B12 deficiency leads to demyelination of the posterior and lateral columns of the spinal cord.
Folate deficiency is characterized by a peripheral blood smear showing pancytopenia, hypersegmented neutrophils, and macrocytic erythrocytes. 


Symptoms and signs
Vitamin B insufficiency manifests as neurologic abnormalities such as ataxia, decreased proprioception, and diminished vibratory sensation. Other symptoms include glossitis and manifestations of autoimmune gastritis. 

Laboratory results indicate a reduction in hematocrit (Hct) levels, a drop in serum vitamin B12 anti-intrinsic factor antibodies, and an abnormal Schilling test, which assesses impaired absorption of oral vitamin B. 

Folate deficiency manifests as glossitis and diarrhea. Laboratory results indicate a reduction in hematocrit (Hct) and reduced amounts of folate in red blood cells. 

Therapy 
Supplement vitamin B12 for the treatment of vitamin B12 insufficiency. Additionally, provide intrinsic factor supplementation if anemia is caused by autoimmune gastritis.

Treatment for folate deficiency: Supplementation with folic acid