Bone Marrow Flashcards
Hypoplasia
Decreased cell formation
Hyperplasia
Increased cell formation
Aplasia
Lack of cell formation
Dysplasia
Abnormal cell formation
Dysmyelopoiesis
abnormal haematopoiesis resulting in cytopenias and dysplastic cells
Dyserythropoiesis
Abnormal erythrocyte production -> cytopenias and dysplastic cells
Dysgranulopoiesis
abnormal granulocyte production -> cytopenias and dyplastic cells
Myelofibrosis
fibrosis of marrow
Myelophthisis
displacement of haematopoietic tissue by other tissue (fibrosis, inflammation, tumour)
Pancytopenia
concurrent anaemia, thrombocytopenia and leukopenia
Myelodysplasia
abnormal haematopoiesis
Mtylodysplastic syndrome (MDS)
neoplastic disorder resulting in clonal dysplastic cells
Aplastic anaemia
lack of formation of all cell lines causing pancytopenia
Pure red cell aplasia
lack of formation of erythroid cell only
What clinical situation is a bone marrow aspirate indicated in
when haematologic abnormalities are not readily explained by a good history, physical examination and thorough evaluation of clinical pathology data has taken place.
What are indications for bone marrow collection?
Persistent cytopenias
Persistent cytosis
Atypical or immature cells on blood smears
Unexplained Hyperproteinaemia
Hypercalcaemia of unexplained aetiology
Staging malignant neoplasia
Evaluation of iron stores and determination of iron sequestration
Features of acute myeloid leukaemia
- Excess blasts +/- differentiated cells
- can be myeloid, erythroid or megakaryocytic origin
- hypercellular marrow with excess blasts
- Aggressive disease with poor prognosis
Features of chronic myeloid leukaemia
- Excess production of mature cells
- Any cell line
- Hypercellular marrow with low numbers of blasts and ofter marked leukocytosis
- May show dysplasia
Primary Myelodysplasia
neoplastic disorder -> abnormal cell production -> poor pronosis
Secondary myelodysplasia
secondary to drugs, viruses or toxins -> variable prognosis
Causes of myelofibrosis
primary (neoplastic) or secondary (IMHA, drugs, marrow injury)
Causes of myelophthisis
metastatic neoplasia, inflammatory cells
Causes of myelonecrosis
Serous atrophy with starvation, toxins
Causes of persistent cytopenias
Infectious (parvovirus, FeLV, FIV) Toxins (Bracken, chemotherapy) Immune mediated disease Endocrine disease (hypoT, hyperA) Neoplasia
Evidence of dysplasia
- inappropriate release of immature cells
- abnormal morphology
Causes of marked hyperglobulinaemia
- Inflammation
- Lymphoid neoplasia
Differentials for hypercalcaemia
- H yperparathydroidism
- A ddisons (dogs)
- R enal failure (horses)
- D vitamin D toxicosis
- I diopathic (cats)
- O steolysis
- N eoplasia
- S purious
Marrow diseases that cause hypercalcaemia
- Lymphoma (usually T cell)
- Multiple Myeloma (plasma cell tumour)
- Oseolysis
- osteomyelitis
- osteosarcoma
- Metastatic neoplasia
Bone marrow collection sites
Pelvis - iliac crest; med/large dogs
Proximal femur - trochanteric fossa; cats and small dogs
Proximal humerus - obese animals
Sternum - horses
When not to do bone marrow biopsy
Coagulopathy -Warfarin toxicity -DIC -Hepatic disease Caustion if marked thrombocytopenia
