Last updated: Friday, 03, December, 2010
CausesAppropriate Tests

FBC, blood film, reticulocyte count; bilirubin, LD; haptoglobin may be useful for documentation and monitoring.

If acute intra-vascular haemolysis suspected: Schumm's test; haemoglobin - urine.

If chronic intravascular haemolysis suspected: haemosiderin - urine.

Active haemolysis may be present without anaemia if bone marrow reserve is sufficient.

See also Haemolysis-Neonatal

With red cell spherocytosis

Direct antiglobulin test.

Further investigation - consult pathologist.

Autoimmune haemolysis, including


See Immediate and delayed transfusion reactions under Blood transfusion - complications.

Hereditary spherocytosis

Severe burns 

Blood film may also show red cell fragmentation.

Clostridium perfringens septicaemia

With red cell fragmentation ± spherocytosis

Microangiopathic haemolysis

Drug-induced oxidative haemolysis, especially

  • Salicylazosulphapyridine
  • Dapsone
  • Phenacetin
  • Primaquine

Heinz body preparation ± methaemoglobin, sulphaemoglobin.

Consider possibility of underlying intrinsic red cell defect.


Particularly in patients with G-6-PD deficiency.

Intrinsic red cell defects, especially

Unstable haemoglobin screening test, haemoglobin electrophoresis.

  • Pyruvate kinase deficiency 

Pyruvate kinase - red cell assay.

  • Other red cell enzyme deficiency 

Autohaemolysis test, further investigation in specialised laboratory.

With sickle cells

Sickle cell disorders

With normal red cell morphology


Paroxysmal nocturnal haemoglobinuria

Flow cytometry evaluation.

Paroxysmal cold haemoglobinuria 

Donath Landsteiner antibody test.

March haemoglobinuria 

Haemoglobin - urine, after exercise.

Intrinsic red cell defects 

Red cell morphology may be unremarkable in patients with sickle cell trait, G-6-PD deficiency or an unstable haemoglobinopathy, particularly when haemolysis is not active.

See also Haemoglobinopathy and Sickle cell disorders

With red cell parasites

Parasites - blood film.