Bone Marrow Examination

Essentials

• Bone marrow examination is necessary for confirmation or exclusion of haematological malignancies.
• Often it is practical to refer the patient to such hospital outpatient clinic where also other investigations, such as flowcytometric analysis and/or cytomolecular genetic testing, can be performed. Factors to be taken into account when choosing the investigation place include experience of the staff in the respective location, patient's age, suspected disease and distance to the hospital.
• Peripheral blood smear and bone marrow iron stain are routinely examined together with the bone marrow examination. If necessary, bone marrow examination is supplemented with trephine biopsy (histological bone marrow specimen).

Purpose

• Bone marrow aspiration is used for the exclusion or confirmation of the diagnosis of a blood disease. Bone marrow examination is also needed to determine the prognosis of a blood disease and to monitor the response to treatment (especially in a hospital setting).
• The diagnosis of several diseases is solely or essentially based on bone marrow examination. These include leukaemias Acute Leukaemias in Adults, myelodysplastic syndromes Myelodysplastic Syndromes (MDS), multiple myeloma Multiple Myeloma (Mm), Waldenström's macroglobulinaemia Waldenström's Macroglobulinaemia (WM), bone marrow metastases and some storage diseases.
• Examination of a bone marrow aspiration sample also completes the picture in several other diseases, such as aplastic anaemia, agranulocytosis, idiopathic thrombocytopenic purpura and hypersplenism.

Indications for aspiration

• Undefined anaemia (not iron deficiency anaemia)
• Undefined thrombocytopenia (associated with other changes in the blood picture, rarely as a solitary abnormality)
• Undefined leucocytopenia or leucocytosis
  • CLL followed up often in primary care
  • CML requires hospital investigations
• Abnormalities in several cell lines. Abundant use of alcohol may be associated with similar cytopenias to those in, for example, MDS Myelodysplastic Syndromes (MDS).
• Undefined lymphadenopathy, splenomegaly, hepatomegaly
• Fever of unknown origin
• (Suspected) bone marrow involvement of
  • haematological malignancy
  • metastatic malignancy.
• Follow-up of chemotherapy
• Lymphoma staging
• Local bone pain
• Metabolic diseases of the bone

Indications for trephine biopsy

Puncture

• The usual sites of aspiration biopsy in adults are the sternum (video Bone Marrow Aspiration from Sternum) and the iliac crest (video Bone Marrow Aspiration from the Posterior Iliac Crest).
• Trephine samples are usually taken from the posterior iliac crest.
• In young children, from birth to 1 - (2) years, the medial aspect at the border between the middle and upper third of the tibia is a good site. In older children the posterior iliac crest is the site of choice. This site can also be used for children younger than 2 years.

Interpretation

• Good collaboration between the clinician and the examiner (preferably a laboratory haematologist) is a prerequisite of successful bone marrow examination.
• The examiner should be provided with information about
  • clinical background (also medication)
  • size of the spleen and liver, icterus
  • lymph node status
  • current (at maximum a few days old) blood picture: haemoglobin, haematocrit, MCV, leucocyte count and differential, platelet count. In anaemia reticulocyte count is also useful.
• Fruitful collaboration requires that the examiner is active and clear as regards reporting the results and conclusions. An immediate contact is sometimes necessary if the findings demand an urgent response. Hence the examiner must be provided with the name and contact information (phone number, e-mail) of the clinician in charge.