Books Video icon An illustration of two cells of a film strip. Video Audio icon An illustration of an audio speaker. Audio Software icon An illustration of a 3. Software Images icon An illustration of two photographs. Images Donate icon An illustration of a heart shape Donate Ellipses icon An illustration of text ellipses. Carr,Bernadette F. Author : Bernadette F. Rodak,Jacqueline H. Author : L. Heilmeyer,Herbert Begemann,J. Author : James O. Author : A. Gulati,John K.
Hoffbrand,John E. If you feel that we have violated your copyrights, then please contact us immediately. Friday, November 26, Sign in. Forgot your password? Increased prominence of cyto- plasmic granules is indicative of systemic infection or therapy with growth fac- tors and is known as toxic granulation. Neutrophils develop from myeloblasts through promyelocyte, myelocyte, metamyelocyte, and band forms and progress to mature neutrophils.
Only mature neutrophils and bands are nor- mally found in peripheral blood. Metamyelocytes and myelocytes may be found in pregnancy, infections, and leukemoid reactions. The presence of less mature forms in the peripheral blood is indicative of hematologic malignancy or myelophthisis. They contain a dark, clumped nucleus and a scant rim of blue cytoplasm. The differentiation of T and B cells is very difficult using light microscopy. Atypical or reactive lymphocytes seen in viral infections contain more extensive, malleable cyto- plasm that may encompass surrounding red cells.
Increased numbers are found in parasitic infections and allergic disorders. These are the bigger circulating cells with an eccentric U-shaped nucleus.
They contain blue cytoplasm and are the precursors of the mononuclear phagocyte system macrophages, osteoclasts, alveolar macrophages, Kupfer cells, and microglia. They are involved in inflammation reactions and increased num- bers are also seen in chronic myeloid leukemia. WBC Abnormalities Quantitative anomalies result in leukopenia and leukocytosis.
Main causes of leukope- nia include bone marrow failure aplastic anemia , myelophthisis acute leukemia , drugs immunosuppressive drugs, propylthiouracil , and hypersplenism portal hyper- tension. Main causes of leukocytosis are infection, inflammation, malignancies, and allergic reactions. Derived from bone marrow giant cells called megakaryocytes, they are involved in the cellular mechanisms of primary hemo- stasis leading to the formation of blood clots. The number of platelets per high-power field multiplied by 20, usually estimates the platelet count per microliter.
Alternatively, one should find 1 platelet for every 10 to 20 red cells. Numbers of platelets can decrease due to bone marrow disease myelophthisic bone marrow , consumption disseminated intravascular coagulation , or drugs.
An increase in numbers can be seen in bone marrow overproduction myeloproliferative syndromes or is a normal response to massive bleeding. Pseudo-thrombocytopenia represents clumping of platelets in blood samples collected in EDTA, resulting in spuriously low platelet counts. This phenomenon can be avoided by using citrate to anticoagulate blood samples sent for blood counts. The bone marrow biopsy can be done at the bedside under local anesthesia, although some patients may require low doses of anxiolyt- ics or opioids for the procedure.
Indications and Contraindications The most common indications for bone marrow evaluation are workup of bone marrow malignancies, staging of marrow involvement by metastatic tumors, assessment of infec- tious diseases that may involve the bone marrow i. There are a few absolute contraindications for the procedure, including infection, previous radiation therapy at the site of biopsy, and poor patient coop- eration.
Thrombocytopenia is not a contraindication to bone marrow biopsy, although it may be associated with more procedure-related bleeding. Patients who have a coagulopa- thy require factor replacement or withholding of anticoagulation to minimize bleeding complications.
Technique In adults, the most common places to do the procedure are the posterior and anterior iliac crests, which are accessible and safe locations of active hematopoiesis. Other potential biopsy sites are the sternum and tibia. The posterior iliac crest is the preferred site, as it allows collection of both aspirate and biopsy specimens and is associated with minimal morbidity or complications.
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