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Date of last update: 10/12/2017.

Forum Name: Hematology Topics

Question: Hypersegmented neutrophils - B12 folate normal

 gkarmzag - Tue Mar 24, 2009 6:02 pm

Hello and thanks in advance for your advice. I am a 34 year old female and the last 2 years have had high MCV, consistently around 101. Was found to be folate-deficient and given 5mg/ day folate for 3 months. MCV returned to “normal” or 100.

I was not very convinced by this so decided to take 2mg/day folic acid by using over-the-counter vitamins and a multivitamin/mineral supplement on top and not go back to the doctor. Decided to have blood re-checked after taking 2mg/day of folate for 2 years. MCV 102 and hypersegmented neutrophils. Normal though borderline results: RBC 3.88 (3.8), Hct 0.395 (0.37). RBC folate and serum folate, Ferritin, serum B12, homocysteine are all normal. C677T MTHFR deficiency, pernicious anaemia, caeliac disease tests all negative. Liver and thyroid normal. My diet is good and am not an alcoholic.

Additional info: benign telangiectasia, patches of hyperpigmentation on skin (face and stomach). My MCV has steadily increased in the last 15 years, from 90 to 102.

I would appreciate any advice on what may be causing the hypersegmented neutrophils and the megaloblastic anemia. I am worried that it could be myelodysplastic syndrome. Best wishes, Lynda
 Dr.M.jagesh kamath - Wed Aug 11, 2010 5:54 am

User avatar Hello,While megaloblastic anaemias caused by B12 and folic acid are the commonest cause of an increased MCV,Non megaloblastic macrocytosis should be considered if other parameters are normal especially if there are no macro-ovalocytes in the peripheral smear and RDW ie Red cell distribution width is normal.
Chronic liver disease in women,chronic alcohol use can also cause isolated MCV increase but would not show hypersegmented neutrophils.
If there is persistent despite therapy you may have to get a bone marrow.Do consult an hematologist.Your previous history suggests only a mild persistence of deficiency.
Best wishes.
 Dr.M.Aroon kamath - Thu Aug 12, 2010 2:48 pm

User avatar Hi,
Dr.Jagesh has dealt with the various possibilities concisely. I would just add a few points that may be relevant.

Hypersegmented neutrophils may be seen in the following conditions apart from vitamin B12 and folic acid deficiencies.
- as a familial feature,
- in chronic infections,
- following cancer chemotherapy,
- in renal failure,and

- in some cases of iron deficiency anemia(mechanism unclear).

The importance of Hypersegmented neutrophils in iron deficiency is that in cases where there is a combined deficiency(dominant iron deficiency with early B12 and folic acid deficiency) and there are no macrocytes(masking effect due to iron deficiency), it may lead to a situation where the underlying vitamin B12 or folic acid deficiency may be missed.
Best wishes!

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