- Presence of spherocytes on peripheral blood smear
- Increased mean corpuscular hemoglobin concentration (MCHC) (> 36 g/dL [360 g/L])
- Increased lysis in osmotic fragility test and reduced fluorescence signal in eosin-5-maleimide (EMA) binding test
Diagnosis of HS does not necessarily require molecular analysis of affected genes.
2012 British Committee Standards in Haematology (BCSH) expert guideline on diagnosis of hereditary spherocytosis recommendations: