Investigations of haemolytic anaemia

• full blood count:
  • reticulocytosis - present if there is increased red cell production
    
• blood film:
  • polychromasia, macrocytosis: increased red cell production
  • spherocytosis: hereditary spherocytosis
  • elliptocytosis: hereditary elliptocytosis
  • sickle cells
    
• bilirubin - increased in unconjugated bilirubin if there is increased red cell destruction (also increased urinary urobilinogen and reduced haptoglobin)
  
• LDH: increased if red cell destruction
  
• urine:
  • urobilinogen: high if increased RBC destruction
  • haemoglobinuria, haemosiderinuria: present in intravascular causes of RBC destruction

Other tests:

• Coomb's test - tests for autoimmune cause of haemolytic anaemia
• Donath-Landsteiner antibody - if paroxysmal cold haemoglobinuria

Reference

1. Hill QA, Stamps R, Massey E, et al. The diagnosis and management of primary autoimmune haemolytic anaemia. Br J Haematol. 2017 Feb;176(3):395-411.
2. Jäger U, Barcellini W, Broome CM, et al. Diagnosis and treatment of autoimmune hemolytic anemia in adults: recommendations from the First International Consensus Meeting. Blood Rev. 2020 May;41:100648.