Hematology 1: Leukopoiesis, WBC Disorders, and Laboratory Diagnostics

Vocabulary review flashcards covering leukopoiesis, benign and malignant leukocyte disorders, cytochemical staining methods, and microscopy essentials based on Hematology 1 examination material.

Granulopoiesis Maturation Sequence

The morphologic developmental sequence of granulocytes: myeloblast, promyelocyte, myelocyte, metamyelocyte, band cell, and mature segmented granulocyte.

Mast Cells

Tissue cells that share a similar morphologic appearance and functional profile to peripheral blood basophils.

CD34

A surface glycoprotein marker expressed by hematopoietic stem cells utilized for their identification.

Primary (Azurophilic) Granules

Early cytoplasmic granules containing myeloperoxidase ($\text{MPO}$) that first appear during the promyelocyte stage of granulocytic maturation.

Toluidine Blue

A special metachromatic stain used to identify basophils and mast cells in bone marrow or tissue specimens.

Myelocyte

The granulocytic precursor stage distinguished by the initial formation of secondary (specific) granules and the last stage in the series capable of mitotic division.

Leukocyte Alkaline Phosphatase (LAP) Stain

A cytochemical stain used to differentiate chronic myelogenous leukemia ($\text{CML}$, which displays a decreased score) from a leukemoid reaction (which displays an elevated score).

Philadelphia Chromosome

A characteristic cytogenetic abnormality formed by a reciprocal translocation between chromosome 9 and chromosome 22, designated as $t(9;22)$, seen in chronic myelogenous leukemia ($\text{CML}$).

Chédiak-Higashi Syndrome

A hereditary anomaly characterized by abnormal granulocyte maturation with the presence of giant, abnormal lysosomal granules in leukocytes.

Smudge Cells

Fragile, ruptured leukocyte remnants commonly observed in chronic lymphocytic leukemia ($\text{CLL}$), which can be prevented on blood smears by the addition of albumin.

t(15;17)

A specific cytogenetic translocation characteristic of acute promyelocytic leukemia ($\text{APL}$ / $\text{FAB M3}$), which is frequently complicated by disseminated intravascular coagulation ($\text{DIC}$).

CD41

A platelet glycoprotein surface marker expressed by megakaryocytic lineage blasts in acute megakaryoblastic leukemia ($\text{FAB M7}$).

Mott Cells

A morphologic variant of plasma cells characterized by abundant cytoplasmic inclusions of immunoglobulins (Russell bodies) that resemble grape clusters.

Reed-Sternberg Cells

Large, distinctive multinucleated or bilobed giant cells that serve as the defining diagnostic finding in lymph node biopsies of Hodgkin lymphoma.

Pelger-Huët Anomaly

A benign hereditary leukocyte disorder marked by failure of granulocytes to segment beyond the two-lobed ('dumbbell' or 'pince-nez') or band stage, displaying coarse, hyperclumped nuclear chromatin.

Auer Rods

Rod-shaped cytoplasmic inclusions formed by fused primary/azurophilic lysosomal granules found in myeloblasts and promyelocytes in acute myeloid leukemia.

Waldenström Macroglobulinemia

A malignant lymphoproliferative disorder involving lymphoplasmacytoid cells that secrete monoclonal immunoglobulin M ($\text{IgM}$).

Tartrate-Resistant Acid Phosphatase (TRAP)

A cytochemical staining reaction that remains persistently positive in the neoplastic B-lymphocytes of hairy cell leukemia following the addition of L-tartaric acid.

Specific Esterase (Naphthol AS-D Chloroacetate Esterase)

A cytochemical stain that demonstrates strong positive enzyme activity primarily in cells of the granulocytic (neutrophilic) lineage.

Non-Specific Esterase (Alpha-Naphthyl Acetate Esterase)

A cytochemical stain used to identify blast cells of monocytic lineage by demonstrating strongly positive enzymatic activity.

Döhle Bodies

Light blue, oval or round leukocyte inclusions composed of ribosomal RNA (rough endoplasmic reticulum) seen in the cytoplasm of granulocytes on Wright-stained peripheral smears.

Alder-Reilly Anomaly

A hereditary metabolic storage disorder in which leukocytes accumulate abnormal mucopolysaccharides, forming dense azurophilic granules that closely resemble toxic granulation.

May-Hegglin Anomaly

An inherited disorder characterized by Döhle-like cytoplasmic inclusion bodies in neutrophils, thrombocytopenia, and giant, poorly granulated platelets.

LE Cell

A segmented neutrophil that has ingested a denatured, homogeneous mass of nuclear protein (antinuclear antibody-coated chromatin).

Tart Cell

A monocyte or histiocyte that has engulfed an intact, morphologically recognizable cell nucleus, distinct from an LE cell.

Terminal Deoxynucleotidyl Transferase (TdT)

A specialized DNA polymerase and intracellular enzyme whose elevated activity is a sensitive marker for primitive lymphoid cells in acute lymphoblastic leukemia ($\text{ALL}$).

Microscope Condenser

The sub-stage lens system responsible for concentrating and directing light through the specimen slide to ensure uniform, even illumination.