Diagnosis and monitoring of various hematological diseases depends on bone marrow examination, especially given that the pathological process in the bone. Often cytological study of spinal be correlated with histological examination of biopsy bone-marrow bringing quantitative and architectural information.

Also, in some cases, bone marrow examination is completed by performing specific stains necessary for evaluating iron stores (Perls stain / Prussian blue), the differential diagnosis of acute leukemia (cytochemical staining for myeloperoxidase, nonspecific esterases, PAS) lipidosis diagnosis (PAS stain in Gaucher disease) or cytogenetic or molecular studies.


Megaloblastic anemia diagnosis;

The diagnosis of multiple myeloma;

Lipidosis diagnosis: Gaucher disease, Niemann-Pick disease, syndrome of “blue like the sea” histiocytes ;

Investigation of cytopenias without apparent cause for confirmation / refutation of leukemias, myelodysplastic syndrome, hypo / aplastic anemia, agranulocytosis;

Diagnosis, classification and monitoring of acute leukemia;

Diagnosis and monitoring of myelodysplastic syndromes;

In chronic myelogenous leukemia, for cytogenetic examination and diagnosis of accelerated phase or blast spurt;

Rarely microcytic hypochromic anemia in the investigation for differentiating iron deficiency anemia from anemia of chronic disease through research deposits of iron (hemosiderin) bone marrow;

Waldenström disease diagnosis;

Method – initially at low power microscopic examination (objective 10x / 20x) and 100x immersion objective; should be assessed at least 500 nucleated cells intact, excluding the free nuclei. The counting is performed in an area where few are free nuclei, the cells do not overlap, they are not grouped or distorted. This is usually located in the central area adjacent cells dispersed. Note that clogs may be absent in pediatric marrow and the marrow will appear as a uniform dispersion of cells.

Clinical significance :

Marrow smear is evaluated according to the following criteria:

I. Cell: the most valuable information is obtained on the basis of bone marrow cellularity histology of osteomedular biopsy the ratio of fat and hematopoietic tissue spaces is 1-2 / 1 in normal adults and a real hipocell marrow is considered when there is a reduction in cellularity <25%.

II. Erythropoiesis :. Red Series is appreciated in terms of quantity and quality. Report erythroblasts granular (G / E) is the ratio between + neutrophilic granulocytes and their precursors and erythroid precursors is 2-4 / 1 in normal adults and lowering this ratio is found in erythroid hyperplasia (increased number of marrow erythroid precursors) that accompanies various types of anemia (iron deficiency anemia, megaloblastic anemia, sideroblastic anemia, thalassemia). The report is marked low / reverse in regenerative anemia (posthaemorrhagic / hemolytic). Increasing the ratio G / E series indicate either granulocyte hyperplasia or red cell aplasia.

Megaloblastic erythropoiesis, which appears in deficiency of vitamin B12 or folic acid, is characterized by increasing cell size with increasing ratio cytoplasm / nucleus (most abundant cytoplasm) and asynchrony / dissociation nucleo-cytoplasmic, with the core having a look immature (low heterochromatin and paracromatine increased) compared with the appearance of the cytoplasm. binucleated.

III. Granulopoiesis : granulocyte precursors that can be identified in bone marrow are myeloblastic, promyelocytic, myelocytic neutrophil / eosinophil / basophil and metamielocyte, which are found with non-segmented and segmented neutrophils mature forms / eosinophil / basophil. Myeloid cells in the bone is predominant element, mature cells are the most numerous. An increased number of immature cells usually indicate a pathological process.

IV. Megakaryopoiesis: basophils can identify megakaryocytes (10-15% of total), granular megakaryocytes (60-70%) and megakaryocytes thrombocytogenes (10-20%). Megakaryocytes are very large cells (30-150 μm), polyploid (8N, 16N, 32N, etc.) 4. Intensely basophilic cytoplasm of megakaryocytes have basophils (increased number of ribosomes) megakaryocytes are less abundant cell type in the bone that usually <1%.

V. Marrow lymphocytes are usually present in small lymphocytes. Lymphocytes and plasma cells are cells in the bone most unevenly distributed.

VI. Marrow monocytes are identical to those in the peripheral blood. Macrophages (histiocytes) bone marrow are large cells with nucleus-cytoplasm ratio decreased cytoplasm with irregular contour, gray, with numerous small grain size and grain size red-purple azurophilic higher variable number of particles ingested (whole cells / destroyed nuclei granules of hemosiderin, etc.) and vacuoles, mostly reflecting pinocytosis cell periphery; nucleus is small, oval, usually single, but can be multiple eccentrically located, with evenly distributed chromatin, nucleolus at least one obvious; active histiocytes have more condensed chromatin.

VII. Non-hematopoietic cells can sometimes be seen on smears of bone marrow are adipocytes (in hypoplastic / aplastic anemia), stromal cells, reticular cells, osteoblasts and osteoclasts (especially in children and bone fetalaosteoblastias be distinguished from plasma cells and osteoclasts of megakariocytes or bone marrow metastases) 5 mast (in hypo / aplastic anemia, lymphoma, chronic lymphocytic leukemia, infectious diseases, systemic mastocytosis). Normally, these cells represent <1% of bone marrow cellularity.

VIII. Atypical cells: can be represented by blast cells, myeloma cells, lymphoma or carcinoma cells.