HOW I DO – Anemia – PART – 24

HOW I DO – Anemia – PART – 24

(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)

Question: In last part, we covered some very important points re anemia with low MCV 1. Thalassemia minor people also can get iron deficiency, and if confirmed, must be given iron supplement like any other patient of iron deficiency. 2. Hb electrophoresis can be false during state of iron deficiency. 3. Hb in thalassemia minor is never below 10. If below 10, they must be investigated for anemia. 4. Explain importance of prenatal testing to any person with thalassemia minor. Just a one minute reminder, especially in young people is very important. 5. Hemoglobinopathies are the second most common cause of low MCV after iron deficiency. Most commonly thalassemia, sickle cell disease, Hb E disease. 6. Alpha thalassemia minor is not detected by Hb electrophoresis. Requires genetic testing.

Are there any other causes of anemia with low MCV?

Answer: Yes there are many more. But they are much less common. We can talk about the few comparatively more common causes.

1. Most important in our practice as Hematologists is MDS – Myelodysplastic syndrome. MDS has many subtypes, and mostly they have high MCV. But a small number can have low MCV, due to an acquired alpha thalassemia type mechanism and phenotype, most commonly RARS – refractory anemia with ringed sideroblasts. So once common causes are ruled out as noted above, we consider bone marrow biopsy to rule out MDS.
2. Alcohol use – again mostly high MCV, but sometimes low MCV. Not just due to iron deficiency, but some effects on bone marrow also can lead to these changes.
3. Anemia of chronic disease (ACD). Also known as anemia associated with SIRS or Anemia associated with Inflammation. Acute and chronic infection or inflammation both can cause this. Hence anemia of chronic disease is not accurate term. A wide variety of infections, inflammatory conditions can cause this. MCV is mostly normal however. Low sometimes, but not too low. Very low MCV means additional iron deficiency likely, or a Hemoglobinopathy.
4. Lead poisoning – Another important differential for hematologists especially. Red cells are small, but more characteristically also have basophilic stippling. In an unexplained anemia, with low MCV, basophilic stippling, with normal Hb electrophoresis, lead poisoning is a very important differential diagnosis. In India, most common reason in our practice is ayurvedic medicines/supplements. Latest patient we saw developed lead poisoning with anemia within about 3 months of ayurvedic medicines taken for infertility treatment. These patients may develop, over long term, peripheral neuropathy as well. Some have significant abdominal pain. Lead level in blood is widely available now with larger labs in our region. And it is diagnostic.
5. Copper deficiency – found in small bowel diseases, bariatric surgery (weight reduction surgery), prolonged TPN, excess zinc (such as from supplements, denture adhesives, homeopathy medicines)
6. Zinc deficiency – most commonly in patients with inflammatory bowel disorder (e.g. Crohn’s)
7. Some medicines – INH is perhaps the most commonly linked medicine. But in real life we see much less siderblastic anemia as most patients are prescribed pyridoxine along with INH (that is given to prevent neuropathy but it also prevents low mcv anemia).

Chloramphenicol is now used rarely. Linezolid, a commonly used antibiotic is an uncommon cause.

June 15^th 2026 Dr Chirag A. Shah; M.D. Oncology/Hematology (USA), 9998084001. Diplomate American Board of Oncology and Hematology. Ahmedabad. drchiragashah@gmail.com   www.shyamhemoncclinic.com