Expansion
Each morphological abnormality points to a specific diagnosis
Mnemonic
Each morphological finding points to a diagnosis:
- Target cells - liver disease, thalassaemia, iron deficiency, hyposplenism
- Howell-Jolly bodies - hyposplenism, nuclear remnants normally removed by the spleen
- Spherocytes - hereditary spherocytosis or autoimmune haemolysis
- Schistocytes (fragments) - microangiopathy: DIC, TTP, HUS, mechanical valves
- Sickle cells - sickle cell disease
- Pencil cells - iron deficiency
- Basophilic stippling - lead poisoning, thalassaemia, sideroblastic anaemia
- Heinz bodies and bite cells - G6PD deficiency
- Hypersegmented neutrophils - B12 or folate deficiency
- Rouleaux - myeloma, raised ESR
- Smear (smudge) cells - chronic lymphocytic leukaemia
- Auer rods - acute myeloid leukaemia
- Tear drop cells - myelofibrosis
“Howell-Jolly means no spleen; schistocytes mean something is shredding the cells; hypersegmented means megaloblastic.” Those three carry most of the clinical weight.
Expansion
| Finding | Suggests |
|---|---|
| Schistocytes (fragments) | Microangiopathic haemolysis: DIC, TTP, HUS; prosthetic valve |
| Spherocytes | Hereditary spherocytosis, autoimmune haemolysis |
| Target cells | Liver disease, thalassaemia, iron deficiency, hyposplenism |
| Howell-Jolly bodies | Hyposplenism or splenectomy |
| Heinz bodies and bite cells | G6PD deficiency |
| Basophilic stippling | Lead poisoning, thalassaemia, sideroblastic anaemia |
| Hypersegmented neutrophils | B12 or folate deficiency |
| Rouleaux | Myeloma, high ESR states |
| Teardrop cells | Myelofibrosis, marrow infiltration |
| Smudge cells | CLL |
| Auer rods | AML |
| Sickle cells | Sickle cell disease |
| Leucoerythroblastic film | Marrow infiltration or fibrosis |
The leucoerythroblastic picture (nucleated red cells and immature white cells together) is worth singling out: it means the marrow architecture is disrupted, by malignant infiltration, myelofibrosis or severe sepsis, and always warrants investigation.
Blister and bite cells with Heinz bodies after an oxidative stress in a male of African or Mediterranean origin is essentially diagnostic of G6PD deficiency.