title: Alpha-thalassaemia trait as a cause of unexplained microcytosis in a South African population.
abstract: BACKGROUND
  Red cell microcytosis is a common abnormality detected in a full blood count, which often prompts clinicians to investigate further for a cause. In the absence of iron deficiency and anaemia of chronic disease, the differential diagnosis includes β-thalassaemia trait and α-thalassaemia trait.
  
  
  METHODS
  We investigated the contribution of α-thalassaemia trait in South African subjects with unexplained microcytosis. Iron studies, haemoglobin subfractionation and multiplex polymerase chain reaction (PCR) analysis for α-globin gene deletions were performed on 97 controls and 86 patients.
  
  
  RESULTS
  After excluding iron deficiency, anaemia of chronic disease and β-thalassaemia trait, 78.0% of subjects with unexplained microcytosis were confirmed on PCR analysis to have α-thalassaemia trait.
  
  
  CONCLUSIONS
  Alpha-thalassaemia trait accounts for the majority of unexplained microcytosis.
authors.affiliation: Department of Molecular Medicine and Haematology, School of Pathology, University of the Witwatersrand and National Health Laboratory Service, Johannesburg, South Africa. sakina.loonat@nhls.ac.za.
authors.forename: Sakina Bibi
authors.initials: SB
authors.lastname: Loonat
authors.forename: Nitien Hira
authors.initials: NH
authors.lastname: Naran
authors.forename: Swee Lay
authors.initials: SL
authors.lastname: Thein
authors.forename: Nazeer Ahmed
authors.initials: NA
authors.lastname: Alli