HOW I DO – Anemia – PART – 23 HOW I DO – Anemia – 23 – Thalassemia minor and iron def, Hemoglobinopathies

HOW I DO – Anemia – PART – 23

(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 1. Celiac disease can lead to poor absorption of oral iron, although a rare disease in our region. 2. More common issue is Helminths – worms. Even in adults it is possible. Hence 3 days of albendazole. 3. IV iron is the only recourse in some patients, who don’t improve in spite of good diet, or oral iron. 4. Role of diet counselling. 5. Oral iron options. Preferably empty stomach, but if not tolerated than after meal. 6. Role of long term oral iron supplement, at least 6-12 months even after Hb is normal. Maintenance course every weekend. Goal Ferritin level near 100. 7. IV iron options. FCM most commonly used. In case of reaction, or otherwise also, may use Ferric derisomaltose.

One question that commonly comes up however is that if patient has Thalassemia Minor, he/she cannot be given iron supplements. You did mention earlier that if MCV is low, but RBC count is not low, it could be Thalassemia minor. Should we be checking everyone for thalassemia than before treating with iron supplements?

Answer: GOOD question. This is a frequent question and concern. Not sure where this comes from, but probably due to non availability/cost of iron profile and thalassemia tests few decades ago. That time a lot of diagnosis was indirect based on indices in a cbc report, like MCV Red cell count RDW. However, please note following points:

1. There is absolutely no contraindication to give iron supplements in any form to a patient with confirmed or suspected thalassemia minor. They can also develop iron deficiency like any other person.
2. Tests are widely available now and cost effective. Iron profile especially ferritin should be done to confirm iron deficiency. And if confirmed, should be treated like any other person and monitored like any other person.
3. Test for thalassemia i.e. Hb electrophoresis can be false during state of iron deficiency. Hence it is advisable not to test during this time, or repeat test after several months once iron deficiency is corrected.
4. Patients with Thalassemia minor can have lowest Hb up to about 10. But many have completely normal i.e. 12 to 14 or so. Hence a thalassemia patient should be evaluated and treated like other people, if their Hb drops below their baseline. If their baseline i.e. their best Hb is not known, treat them for iron deficiency to full extent, and see what level of Hb they achieve.
5. If a thalassemia patient has low Hb, it must not be assumed to be due to thalassemia. As explained above, evaluate and treat. We see a number of patients with Hb of 7 or 8 and not being treated as they carry a diagnosis of thalassemia minor. Below 10, cannot be Thalassemia minor!
6. Thalassemia patients have low MCV. Hence it cannot be used as a screening test for iron deficiency. They can have other causes as well, and yet maintain low MCV.
7. If you see a patient with Thalassemia first time, always take couple of minutes to explain importance of prenatal testing. i.e. if patient and spouse both are minor, child can have thalassemia major. And how this is preventable by prenatal testing which is widely available and very cost effective too. Even if patient is very young, parents or patient may remember your words when they get married. And you would have done them a great service!

Que: Thank you so much for this clarity. What about other causes of low MCV?

Ans: Yes there are few other causes of low MCV. Not very common but worth keeping in mind.

Hemoglobinopathy, other than Beta Thalassemia. When we use the word thalassemia minor, we mean beta thalassemia as that is the most frequent cause in India. However, many other hemoglobinopathies can present with anemia and low MCV. Hb electrophoresis is the initial test of choice for diagnosis. Sickle cell disease is next most common after thalassemia. Hb E disease is common in Eastern India, and Northeast states, and neighboring  countries on that border. By itself it is mild, but with beta thalassemia combined, can have more severe anemia.

Some cases need more detailed testing with genetic profile however for detailed diagnosis. Hb electrophoresis may or may not flag them, but will not confirm. I saw two such cases recently. One was flagged in Hb electrophoresis as an abnormal band but confirmed to be a rare subtype in genetic test i.e. Hb Deer Lodge.

Other one was a very committed young lady who wants to be a Pilot. No other career choice! For a flight pilot, Hb has to be in normal range, otherwise you don’t get entry during training itself. Her Hb was 10.6. With low MCV. For thalassemia minor, this is ok, and they are allowed to fly planes. However, her Hb electrophoresis came back as normal. Now patient and mother were very sad. She had already tried very good iron rich diet. We asked for genetic profile, and fortunately this turned out to be ALPHA Thalassemia minor. Alpha thalassemia minor can not be diagnosed with Hb electrophoresis. Requires molecular testing. For an average person, this does not matter. Since patients with alpha thalassemia minor live a normal life, and there is no concern with prenatal diagnosis as well. Hence, we don’t routinely order this test. So, now this young lady is in pilot training, and I am waiting to hear her name in few years, while I am flying! This is your Captain speaking….

May 10^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