Iron Deficiency or Thalassaemia Trait? Understanding Low MCV

A low MCV can reflect iron deficiency or inherited thalassaemia trait. These conditions are different and should not automatically receive the same treatment.

Symptoms, causes and key details

Low ferritin suggests reduced iron stores, whereas red cell counts can be relatively high in thalassaemia trait. Iron studies and, when appropriate, haemoglobin electrophoresis or genetic tests help distinguish them.

Assessment and practical next steps

Bring previous blood counts, family history and details of iron supplements to your clinician. Do not use iron solely for thalassaemia trait unless deficiency is confirmed.

When is urgent help needed?

Severe breathlessness, chest pain or fainting need urgent assessment; reproductive planning may benefit from genetic counselling.

Frequently asked question

Is thalassaemia trait contagious?

No, it is inherited.

This article provides general information, not a personal diagnosis or treatment.

Trusted information source: https://www.nhs.uk/conditions/thalassaemia/