Hematology terms

Hematology terms

A

Alder-Reilly anomaly:  Metachromatic granules surrounded by clear zone in lymphocytes, associated with the genetic mucopolysaccharidoses, due to lack the lysosomal enzymes necessary to break down mucopolysaccharides

Amyloid: Amorphously deposited fibrillary protein, non-branching fibrils in a beta-pleated sheet conformation; can be monoclonal immunoglobulin; positive for Congo Red; suggestive of B cell disorder

Anisocytosis: Red cells unequal in size, commonly seen in anemia

Auer rod: Needle shaped cytoplasmic azurophilic granular material, associated with APL with PML-RARA, and AML with t(8;21)(q22;q22.1)

B

Bence Jones proteins: Free light chains without attached heavy chains

C

Cloverleaf/flower cells: Neoplastic T cells with agranular basophilic cytoplasm, multilobated nuclei, in the appearance of clover leaf, seen in adult T cell leukemia/lymphoma

Coombs test

• Direct: Detect antibodies/complements attached to surface of patient red blood cells
• Indirect: Detects plasma/serum antibodies against foreign red blood cells, usually for blood match prior to transfusion

D

D-dimer: A fibrin degradation products formed by plasmin degradation of fibrin, indicators of abnormal thrombus formation, elevated levels can be seen in thrombosis, disseminated intravascular coagulation, trauma, malignancy, etc

Döhle bodies: Single or multiple blue cytoplasmic inclusion, remnants of rough endoplasmic reticulum retained from a more immature state, associated with myeloid "left shifts"

Dutcher bodies: Intranuclear crystalline inclusion, containing immunoglobulin, seen in neoplastic plasma cells

F

Faggot cells: Cells containing bundles of Auer rods

Fibrin-fibrinogen degradation products (FDP): Detect fibrin fragments broken by plasmin, normally less than 10 microgram/ml, commonly used in diagnosis of disseminated intravascular coagulation (DIC)

H 

Hemophagocytosis: Phagocytosis of phagocytosis of erythrocytes, lymphocytes or other hematopoietic precursors by histiocytes or macrophages in bone marrow, lymph nodes, liver or spleen. Can be seen in Chediak Higashi syndrome, hemophagocytic lymphohistiocytosis, certain leukemia, small cell carcinoma and other malignant tumors. 

Howell Jolly body: Spheric or ovoid eccentrically located granules, nuclear remnant in red blood cells, associated with hyposplenism

Hyperviscosity syndrome: Symptoms caused by elevated blood proteins, such as immunoglobulin, including principally of the triad of mucosal bleeding, visual changes, and neurologic symptoms

Hypersegmentation: Abnormally increased nuclear lobulation in granulocytes, associated with megaloblastic anemia
 

I

Immunofixation: Detection of any possible paraproteins using anti-serum (Anti-IgG, Anti-IgM, Anti-IgA, anti-Kappa, Anti-Lambda), after electrophoresis of serum or urine; positive if narrow discrete bands are seen

International normalized ratio (INR): A calculation used to standardize prothrombin time (PT), especially for patients using warfarin, an arbitrary level for estimate risk of bleeding, therapeutic goal is usually a value of 2-3

L

Left shift: Increased circulating immature leukocytes, usually neutrophils, caused by releasing of stored leukocytes, associated with bacterial infection

Leukemoid reaction: Neutrophils above 50 x 10³/mm³, more immature cells, particularly myelocytes, associated with severe infection, intoxications, severe hemorrhage, acute hemolysis, etc

Leukoerythroblastosis: Nucleated erythroid and early granulocyte progenitors in peripheral blood, due to premature release, can be seen at granulomatous marrow diseases, hairy cell leukemia, primary myelofibrosis, spent phase of polycythemia vera, metastatic cancers 

Light chain restriction: Monotypic expression of light chain in a B cell subset, either kappa or lambda, usually a strong indicator of B cell/plasma cell neoplastic growth

M 

“M” component/paraprotein: Monoclonal immunoglobulin 

May-Hegglin anomaly: Dohle-like bodies and background giant platelets, autosomal dominant, may be associated with thrombocytopenia and bleeding

Mixing studies: Tests of PT or aPTT after mixing patient’s plasma with equal volume of normal plasma, used to determine if prolonged PT or aPTT is due to deficiency of coagulation factors or presence of inhibitors

Mott cells: Plasma cells with grapelike cytoplasmic inclusions (Russell bodies), containing immunoglobulin

N 

Nucleated red blood cell: Circulating immature red blood cells with nuclei, associated with marrow damage, stress, hyposplenism, ectopic hematopoiesis, etc

P

Pappenheimer bodies: Iron containing granules in circulating red blood cells, associated with post splenectomy status, myelodysplasia, hemolytic anemia, lead poisoning, sickle cell disease,etc

Paraproteinemic neuropathy: A heterogeneous set of disease or degenerative state of the peripheral nerves in which motor, sensory, or vasomotor nerve fibers are affected, with the presence of homogeneous immunoglobulin in the serum. Clinical presentations include muscle weakness and atrophy, pain, and numbness

Pelger-Huet anomaly: Less segmentation of granulocyte nuclei, autosomal dominant, normal cell function

Petechiae: Pin point type skin or mucosa hemorrhage, usually associated with primary hemostasis defects

Poikilocytosis: Red cells with abnormal shapes.

Pseudo Pelger-Huet cells: Neutrophils with bilobed nuclei, seen in myelodysplasia, AML, chronic myelogenous leukemia, result of drugs like colchicine and sulfonamides, mycoplasma infection

R

Ringed sideroblast: Red cell precursors with small iron granule deposit surrounding nuclei

Rouleaux Formation: Stack of red cells in chains, usually associated with elevated levers of serum proteins, particularly fibrinogen and globulins

Russell bodies: Cytoplasmic cherry red refractive round bodies in plasma cells, containing immunoglobulin, associated with plasma neoplasm

S

Schistocyte: Fragmented red cells, seen in thrombotic thrombocytopenic purpura or hemolytic-uremic syndrome and atypical hemolytic-uremic syndrome 

Sézary cells: Clonal neoplastic CD4+ T cells, with cerebriform nuclei. Seen in mycosis fungoides

Sideroblast: Red cell precursors with small iron granule deposit surrounding nuclei

Smudge cells: AKA basket cells, leukocytes without cytoplasm, due to physical "smash" during peripheral blood smear making process, associated with increased fragility, seen in CLL, infectious mononucleosis, other hematopoietic proliferative disorders, or degenerated blood sample

Spherocytes: Sphere-shaped red blood cells, associated with all types of hemolytic anemia, especially autoimmune hemolytic anemia, and hereditary spherocytosis

T

Target cell: AKA codocyte, red cells with the appearance of a shooting target, associated with thalassemia, hemoglobin C disease, hyposplenism such as post splenectomy or autosplenectomy in sickle cell disease, or certain liver disease

Teardrop-shape red blood cell: AKA dacrocyte, red cells in the shape of a tear drop, associated with primary myelofibrosis, myelodysplastic syndrome (MDS), and occasionally acute leukemias and metastatic carcinoma

Tingible body macrophages: Macrophages with irregular cellular debris, commonly seen in germinal center of lymph nodes

Toxic granulation:  Prominence of dark coarse azurophilic granule, associated with severe inflammatory and left shift

W

Waldenstrom macroglobulinemia: Syndrome with serum IgM monoclonal gammopathy, monoclonal light chains (Bence-Jones protein) in urine, hyperviscosity, presence of B cell neoplasm, especially Lymphoplasmacytic lymphoma


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