What Causes Megaloblastic Anemia?

Posted on Tue, 22 Jul 2014

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Tue, 22 Jul 2014 Answered on

Wed, 13 Aug 2014 Last reviewed on

Question : why do I have megaloblastic anemia when my b-12 andfolic acis levels are good?

Answered by Dr. Monish De (7 hours later)

Brief Answer:
malabsorption

Detailed Answer:
Hi
The most common causes of megaloblastic anemia are deficiencies of either folic acid or of vitamin B12.
Since you had colon cancer resection you must be having malabsorption in the intestines which is causing a lack of vitamin B12 leading to megaloblastic anemia. Some other causes include alcohol abuse, chemotherapy, leukemia, certain medications, and some genetic conditions.
Hope i have answered your query.
Regards
DR De

Above answer was peer-reviewed by : Dr. Bhagyalaxmi Nalaparaju

Follow up: Dr. Monish De (6 hours later)

but this was evident for the last year in my blood work.

Answered by Dr. Monish De (36 minutes later)

Brief Answer:
Endoscopy

Detailed Answer:
Hi,

There are some gluten enteropathy diseases like coeliac disease which causes megaloblastic anaemia inspite of normal vitamin B12 and folic acid in blood.

That is why you must exclude this disease by doing further blood tests for Immunoglobulin A and anti-tissue transglutaminase antibody and if these antibodies are found in blood then a small intestine biopsy which is done by upper gastrointestinal endoscopy where a small tube is guided down a person's throat to the small intestine is recommended.

Regards
DR De

Above answer was peer-reviewed by : Dr. Ashwin Bhandari

Follow up: Dr. Monish De (5 hours later)

if my mcv is 103, is that clinically significant

Answered by Dr. Monish De (21 hours later)

Brief Answer:
folate deficiency and Vitamin B12 deficiency

Detailed Answer:
Hi

Mean corpuscular volume that is MCV is the average volume of red cells in your blood.
Its normal range is 80-96 fL/red cell in adult.
Increased MCV which is 103 in your case indicates to macrocytic anaemia due to folate deficiency and Vitamin B12 deficiency.
That is why I would recommend upper gastrointestinal endoscopy in your case to to find the cause of the above deficiencies.

Regards
Dr De

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Monish De (53 minutes later)

I just had that with my colonscopy in May. My B12 and folic levels are good

Answered by Dr. Monish De (8 minutes later)

Brief Answer:
Duodenum

Detailed Answer:
Hi
Colonoscopy includes the anus, rectum, colon, and cecum.It does not include duodenum.
That is why i recommend upper GI endoscopy which includes the esophagus, stomach and duodenum where the cause of your megaloblastic anaemia may lie.
Regards
DR De

Above answer was peer-reviewed by : Dr. Vinay Bhardwaj

Follow up: Dr. Monish De (7 hours later)

that was done because I had heartburn and the dr said we needed to that.
everything was ok. I have had a reading of slightly over 100 over the last
five years bot my primary dr said it was not anything but then they changed
the normal from 100 to 96-now we are concerned??

Answered by Dr. Monish De (14 hours later)

Brief Answer:
Antibody tests.

Detailed Answer:

Normal MCV ranges from 80-96 fL/red cell in adult.
Your reading is 103.
So definitely that points to vit B12 and folic acid deficiency though its level is normal in blood.

That is why I recommend you to do further blood tests for Immunoglobulin A antibody and anti-tissue transglutaminase antibody and if these antibodies are found positive in blood then a small intestinal biopsy is recommended for finding the cause of megaloblastic anemia.

Regards
DR De

Above answer was peer-reviewed by : Dr. Vaishalee Punj