Hematology: Bone Marrow, Cytochemistry, and Anemia Review

Flashcards covering bone marrow anatomy, collection procedures, cytochemical staining, and the classification and diagnosis of various anemias (IDA, Vitamin B12, and Folate deficiency).

Red marrow

The hematopoietic tissue found within the bony cavities of the axial skeleton that is responsible for producing blood cells.

Yellow marrow

The type of bone marrow used mainly for fat storage.

Neoplasia

The presence of abnormal cells leading to the formation of a tumor.

Cytopenia

A condition characterized by a reduced number of blood cells.

Leukopenia

A specific cytopenia referring to a low white blood cell (WBC) count.

Thrombocytopenia

A specific cytopenia referring to a low platelet count.

Aspiration

A procedure that takes out a small amount of bone marrow fluid through a needle.

Trephine Biopsy

A procedure to obtain a solid core of bone and marrow tissue using a specialized needle with a cutting edge.

Stylet (Trocar)

A component found inside a bone marrow needle that helps prevent bending and adds stability during insertion.

Jamshidi Needle

A type of specialized needle used specifically for obtaining a trephine biopsy.

Posterior Iliac Crest

The most preferred site for bone marrow collection because it provides adequate red marrow and is isolated from structures prone to accidental puncture.

Sternum

A collection site in adults used only as a last resort for aspiration because it is only $1\,\text{cm}$ thick.

Hematoxylin and Eosin (H&E) Stain

A routine stain used for general bone marrow morphology, appearing dark blue/purple in the nuclei and pink in the cytoplasm.

Wright-Giemsa Stain

A Romanowsky stain used for the differentiation of blood cells and the identification of blasts or abnormal cells.

Megakaryocytes

The largest cells in the bone marrow, ranging from $50-100\,\mu\text{m}$ in diameter with multilobed nuclei, used to generate platelets.

Osteoblasts

Non-hematopoietic, bone-forming cells responsible for producing and mineralizing bone matrix; often described as bone-builders.

Osteoclasts

Large multinucleated cells derived from monocytes/macrophages involved in bone demineralization and resorption.

Hypercellular

A core biopsy observation where the marrow is almost $100\%\,\text{occupied}$ by hematopoietic stem cells with almost no space for adipocytes.

M:E Ratio

The ratio of myeloid to erythroid cells in the bone marrow, with a normal range between $2:1$ and $4:1$.

Acid Phosphatase (AcP)

An enzyme located in lysozymes present in all hematopoietic cells; its discrete focal granules in blasts are characteristic of T-cell Acute Lymphocytic Leukemia.

Tartrate-Resistant Acid Phosphatase (TRAP)

A staining technique where acid phosphatase remains positive (dark red granules) after adding tartaric acid, specifically identifying Hairy Cell Leukemia.

Alkaline Phosphatase (AlkP)

An enzyme present in the cytoplasm of neutrophils, referred to as leukocyte alkaline phosphatase (LAP) when used for scoring.

LAP Score

A value calculated by rating 100 mature neutrophils from 0 to 4 based on AlkP staining; normal values are $13-160$.

Periodic Acid Schiff (PAS)

A non-enzymatic stain that detects intracellular glycogen and neutral mucopolysaccharides.

Sudan Black B

A non-enzymatic stain used for detecting lipid components within cells.

Perl's Reaction

A ferric iron stain used to evaluate storage iron in macrophages, which produce a blue-green precipitate.

Anemia

A manifestation of underlying disease characterized by a decrease in the oxygen-carrying capacity of the blood or hemoglobin concentration.

Normocytic, Normochromic Anemia

A classification of anemia where RBCs are normal in size (MCV $80-100\,\text{fL}$) and color (MCHC $32-36\%$), but the overall count is reduced.

Microcytic, Hypochromic Anemia

A classification where RBCs are small (MCV $<80\,\text{fL}$) and pale (MCHC $<32\%$), common in Iron Deficiency Anemia.

Ineffective Erythropoiesis

A mechanism where erythroid precursors are defective and undergo self-destruction in the bone marrow before maturing into RBCs.

Erythron

The collection of RBC precursor cells in the bone marrow.

Pica

A clinical symptom associated with Iron Deficiency Anemia involving the craving and dietary intake of non-food substances like clay or ice.

Koilonychia

A clinical sign of chronic Iron Deficiency Anemia characterized by the spooning of the nails.

Serum Ferritin

The first laboratory result to become abnormal in early Iron Deficiency Anemia, reflecting depleted iron stores.

TIBC (Total Iron-Binding Capacity)

An indirect measure of transferrin levels that increases in response to low iron levels.

Pernicious Anemia

A macrocytic, megaloblastic autoimmune disorder caused by the impaired absorption of Vitamin B12 due to a lack of intrinsic factor.

Intrinsic Factor

A glycoprotein produced by the parietal cells of the stomach necessary for the absorption of Vitamin B12.

Hypersegmented Neutrophils

Neutrophils with more than five nuclear lobes, a key laboratory finding in Vitamin B12 and Folic Acid deficiencies.

Methylmalonic Acid (MMA)

A metabolite that increases in Vitamin B12 deficiency but remains normal in Folic Acid deficiency, aiding in differential diagnosis.

Spina Bifida

A neural tube defect that can occur in a developing embryo if the mother has a Folic Acid deficiency during pregnancy.