Microcytosis without anaemia (suspected thalassaemia trait)
BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.
Microcytosis (low MCV or MCH) without anaemia: tests
Laboratory tests
- Serum ferritin
- Haemoglobin electrophoresis with HbA2 measurement (if ferritin normal; straight away if origin from a high-prevalence region or pregnancy plan)if neededMicrocytosis with normal iron studies, especially if the family origin is suggestive: electrophoresis avoids unnecessary gastrointestinal investigations [2]. Screening recommended before conception and in early pregnancy in people from high-prevalence regions [3]. Severe iron deficiency can mask the rise in HbA2 [1]: if iron-deficient, repeat the electrophoresis after correction [3].
Known or suspected thalassaemia trait and pregnancy planning: screen the partner
Partner's laboratory tests
- FBC (MCV, MCH)
- Serum ferritin
- Haemoglobin electrophoresis with HbA2 measurement
Sources (7)
- NHS England (Office for Health Improvement and Disparities). Sickle cell and thalassaemia screening programme handbook : chapitre « Antenatal screening ». Mis à jour le 11 juillet 2025.
- Snook J, Bhala N, Beales ILP, Cannings D, Kightley C, Logan RP, et al. British Society of Gastroenterology guidelines for the management of iron deficiency anaemia in adults. Gut. 2021;70(11):2030-51.
- Société de pathologie infectieuse de langue française (SPILF), Société française de pédiatrie (SFP), Société française de lutte contre le sida (SFLS). Bilan de santé des personnes migrantes primo-arrivantes. Recommandations, juin 2024 (GT 6.5 : dépistage des hémoglobinopathies).
- Haute Autorité de santé. Diagnostic biologique d'une carence en fer : en première intention, doser la ferritine seule. Fiche Bon usage des technologies de santé, juillet 2011.
- NHS England. Sickle cell and thalassaemia screening programme handbook : chapitre « Understanding haemoglobinopathies ». Mis à jour le 11 juillet 2025.
- Van Vranken M. Evaluation of Microcytosis. Am Fam Physician. 2010;82(9):1117-1122.
- Cario H, Alashkar F, Andres O, Hoferer A, Meisel R, Schmugge Liner M, Sillaber C, Wörmann B. Beta-Thalassämie. Leitlinie Onkopedia (DGHO, OeGHO, SGMO, SSH), Stand Juli 2025.