Module 7 Leukocyte Disorders PDF

MODULE 7 – LEUKOCYTE DISORDERS MODULE OUTCOMES At the end of this module, the intern is able to: 1. discuss comprehensively the etiology and pathophysiology of the different leukocyte disorders. 2. apply systematically the procedural steps in common and special diagnostic laboratory examination of...

MODULE 7 – LEUKOCYTE DISORDERS MODULE OUTCOMES At the end of this module, the intern is able to: 1. discuss comprehensively the etiology and pathophysiology of the different leukocyte disorders. 2. apply systematically the procedural steps in common and special diagnostic laboratory examination of leukocyte disorders 3. interpret correctly laboratory results employed for the diagnosis of leukocytic disorders. INTRODUCTION Disorders affecting white blood cells can be classified broadly as Nonmalignant and Malignant. Nonmalignant leukocyte disorders include conditions that are not caused by clonal or neoplastic changes in hematopoietic precursor cells. These conditions may affect the number, morphology, or function of one or more WBC lineages. On the other hand, malignant leukocyte disorders cover a group of neoplasms known as leukemia. These conditions are grouped according to cell lineage as malignant myeloproliferative disorders and malignant lymphoproliferative disorders. KEY CONCEPTS I. OVERVIEW OF LEUKOCYTE DISORDERS A. Non-malignant Leukocyte disorders 1. Nonmalignant: does not grow and spread in a rapid and uncontrolled way that can cause death 2. Disorder: a physical/mental condition that is not normal or healthy 3. Disorders may be a. Qualitative i. Morphologic alterations ii. Inherited Functional Disorders of WBC iii. Monocyte/Macrophage Lysosomal Storage Diseases b. Quantitative – alterations in number (leukocytosis or leukopenia) B. Malignant Leukocyte disorders 1. Malignant Myeloproliferative Disorders a. Involves the proliferation of cells under the myeloid series b. Includes the following: i. Myelodysplastic Syndromes (MDS) ii. Acute Myeloid Leukemia (AML)/ Acute Myeloproliferative Leukem iii. Myeloproliferative Neoplasms (MPNs)/Chronic Myeloproliferative Disorders 2. Malignant Lymphoproliferative Disorders a. Involves the proliferation of cells under the lymphoid series b. Includes the following: i. Acute lymphoblastic leukemia (ALL) ii. Chronic Lymphoproliferative Disorders (CLLD) iii. Lymphoma iv. Plasma cell dyscrasia II. MORPHOLOGIC ALTERATIONS IN WHITE BLOOD CELLS A. Inherited Abnormalities of Granulocyte Morphology 1. Nuclear abnormalities – e.g. Pelger-Huët anomaly, Neutrophil hypersegmentation, etc 2. Cytoplasmic abnormalities – e.g. May-Hegglin anomaly, Alder-Reilly anomaly B. Pelger-Huët Anomaly (PHA) 1. PHA is the failure of neutrophils to segment (hyposegmentation) with coarseness of chromatin 2. lamin β-receptor gene mutation 3. Inherited (autosomal dominant) 4. Heterozygous: 2 round lobules connected by a fine filament or fails to segment; dumbbell or peanut shaped (pince-nez spectacle appearance) 5. Homozygous: rare; round/oval nucleus 6. PHA is most frequently seen in the heterozygous state 7. “Pseudo” Pelger-Huët Form a. Also a decrease in nuclear segmentation of neutrophils b. Acquired – seen in MDS, AML, CMPDs, patients receiving chemotherapy, severe infections, cancer metastizing to the bone, drugs c. Anomaly is reversible Page 1 of 18  8. Differentiation of PHA and Pseudo-Pelger-Huet Anomaly Pelger-Huet Anomaly Pseudo-Pelger-Huet Anomaly 63-93% of cells affected 5 lobe neutrophils 3. Normal neutrophils have a mean of 4 lobes, no more than 5 lobes Entire cell is greatly enlarged and nuclear material fills the cell 4. Long thin filaments are characteristic of this cell 5. Can be a. Hereditary i. Autosomal dominant – rare, not associated with disease ii. Undritz anomaly iii. Myelokathexis – normal granulocyte production, impaired release; component of WHIM b. Acquired – often seen megaloblastic anemias, also seen in MDS D. Alder-Reilly Anomaly 1. Autosomal recessive 2. Dense blue black (azurophilic) granules in all WBC 3. Resemble toxic granulations 4. Granules composed of partially digested mucopolysaccharides 5. Related to defect in degradation of mucopolysaccharides due to abnormal enzyme 6. Inclusions do not affect function 7. Granules are metachromatic-positive (stain purple with toluidine blue), PAS-positive and peroxidase-negatiive 8. Seen in Hunters and Hurlers disease, Maroteaux-Lamy polydystrophic dwarfism E. Toxic Granules 1. Altered primary granules 2. Dark blue-black/purple granules in neutrophils (metamyelocyte, myelocyte, stabs, and segmenters) 3. Granules cluster within the cell and are peroxidase (+) with ↑ALP 4. Not all neutrophils will be affected 5. Found in severe infections, drug poisoning and burns Alder-Reilly Anomaly Toxic Granulation Dense blue black granules in all WBC Dark blue-black/purple granules in neutrophils No neutrophilia, Dohle bodies and left shift Neutrophilia, Dohle bodies and left shift F. Chédiak-Higashi Syndrome 1. Autosomal recessive 2. Very large reddish-purple or greenish-gray granules in all WBCs 3. Cell granules normal in content but abnormally packaged 4. Defect in the lysosomes responsible for respiratory burst (abnormal packaging of melanosomes) 5. Rare/fatal disorder in children 6. Patient shows albinism, photophobia, mental retardation and poor resistance to infections G. May-Hegglin Anomaly 1. Autosomal dominant, disordered production of myosin heavy chain 2. Syndrome characterized by: a. Leukopenia b. Thrombocytopenia c. Giant bizarre platelets d. Gray-blue spindled-shaped inclusions in granulocytes and monocytes (resemble dӧhle bodies but are larger) 3. Usually asymptomatic, bleeding tendencies in 1/3 of patients H. Dӧhle Bodies 1. Single/multiple light blue/grayish staining areas (1-5 um) in the peripheral cytoplasm of neutrophils 2. Inclusion are remnants of REC containing RNA 3. Seen in infections, poisoning, burns, following chemotherapy, pregnancy Page 2 of 18  May-Hegglin Anomaly inclusions Dӧhle Bodies inclusions Larger Smaller Seen in all WBC (granulocytes and monocytes)! Seen in neutrophils I. Smudge Cells 1. Nuclear remnant of a lymphocyte 2. Thumbprint shaped 3. Seen in high number in chronic lymphocytic leukemia (CLL) J. Basket Cells 1. Nuclear remnants of granulocytes 2. Produced by trauma during smear preparation, a normal finding K. Auer Rods 1. Reddish purple rods (but may be any shape) representing aggregated primary granules 2. Seen in the cytoplasm of myeloblast, monoblast and promylocytes in AML (M3 and M6) 3. Important parameter in prognosis of AML (remission rates of 68% in patients with Auer rods) 4. May be seen in bundles (faggot cells) L. Neutrophil Cytoplasmic Alterations 1. Vacuolation a. Autophagocytosis: caused by drugs, prolonged storage of cells, toxins, radiations; small in size (1-2um) and evenly distributed b. Due to ingestion: septic processes; large (7-8um) and not evenly distributed 2. Degranulation a. Normal function of neutrophils b. 1° and 2° granules emptied into phagosome c. 2° granules secreted into extracellular environment 3. Pseudopods a. Granule-free protrusions of cytoplasm b. Indicative of depressed locomotion c. Caused by bacterial and therapeutic agents 4. Swelling a. Caused by actual osmotic swelling of the cytoplasm or increased glass adhesiveness b. Resulst to neutrophil anisocytosis M. Neutrophil Nuclear Alterations 1. Pyknotic nuclei a. Shrunken and dense nuclei b. Frequently seen in septic conditions 2. Toxic nuclear projections a. Hairlike projections frequently seen in inner side of band forms b. Metastatic carcinoma or after irradiation 3. Ringed nuclei a. Seen in toxic states and malignant myeloproliferative states N. Eosinophil Qualitative Abnormalities 1. Degranulation a. Most prominent alteration b. Decreased granules seen in malignant myeloproliferative disorders 2. Vacuolation a. Unknown significance 3. Hypersegmentation a. ≥3 more lobes b. Cause similar to neutrophil hypersegmentation O. Reactive Lymphocytes 1. Lymphocytes that show morphologic variations from normal mature lymphocytes seen in nonmalignant reactive disorders (not leukemic cells) 2. Other names: Atypical lymphocytes, nonleukemic lymphoblast, Virocytes, Reticular cells, Downey cells, Turk cells, Glandular fever cells, Variant lymphocytes, Leukocytoid lymphocytes, Transformed lymphocytes, Stress lymphocytes, Transitional lymphocytes 3. Produced in response to antigenic stimulation 4. Seen in viral diseases (hepatitis, IM), pneumonia, drug reactions 5. Reference interval: 0 – 0.66 × 109/L (absolute), 0–7.5% (relative) 6. Morphology a. Generally larger cell, 10-20 um b. Nucleus: extremely dense to pale and immature looking, coarse nuclear chromatin c. Cytoplasm: usually abundant; deeply basophilic to pale blue with radial/peripheral basophilia; irregular shape (tags, sharp ridges); indented by red cells Page 3 of 18  7. Downey Classification of Reactive Lymphocytes Type I Type II Type III Size 9-20 um 15-25 um 12-35 um Shape Oval or round Irregular or scalloped Round or irregular Nucleus Dense blocks of chromatin ; Coarse chromatin; Fine chromatin; highly indented or oval round or oval visible nucleoli Cytoplasm Abundant and often Moderately basophilic, may Vacuolated; abundant indented by be vacuolated, foamy or basophilia; clear surrounding structures; contain granules perinuclear area pale blue III. FUNCTIONAL DISORDERS OF WHITE BLOOD CELLS A. Chemotactic Abnormalities 1. Jobs Syndrome a. Chemokinesis (random movement) is normal but chemotaxis (directional movement) is abnormal b. Slow response to chemotactic agent c. Autosomal dominant hyperimmunoglobulin E (IgE) syndrome (HIES) was first described as Job syndrome in 1966 and included the triad of eosinophilia, eczema, and recurrent skin and pulmonary infections (named after the biblical character Job, who was "smote with sore boils"). d. Patient has many boils and furuncles 2. “Lazy Leukocyte” Syndrome a. Chemotaxis and chemokinesis are abnormal b. Neutropenia, but BM granulocytes are normal c. Abnormal susceptibility to bacterial infections B. Defective Killing of Microorganism 1. Chediak Higashi syndrome 2. Congenital C3 deficiency: repeated infections with encapsulated organisms 3. Chronic granulomatous disease (CGD) a. Phagocytes ingest but can’t kill catalase (+) organisms due to lack of respiratory burst b. Most experience recurrent bacterial and fungal infections; granulomas may obstruct organs c. Inheritance: sex-linked recessive (disease of male infants) or autosomal recessive d. Evaluation of Respiratory burst i. Chemiluminescense Normal: resting cells do not emit light, stimulated cells do CGD: resting and stimulated cells do not emit light ii. Nitroblue tetrazolium (NBT) test NBT is a colorless dye; if H2O2 is produced by neutrophils, NBT changed to dark blue formazan Fresh heparinized blood required (EDTA inactivates C1q needed in complement- dependent reaction) Normal: yellow formazan reduced to blue insoluble blue formazan CGD: failure to reduce NBT dye 4. Myeloperoxidase Deficiency a. Deficiency in MPO in the primary granules of neutrophils and lysosomes of monocytes b. Common, autosomal recessive c. Bacterial killing is slow but complete d. Benign condition, patients rarely troubled by infections e. Detected in cell differential counting using automated machines IV. LYSOSOMAL STORAGE DISEASES A. Mucopolysaccharidoses (MPSS) 1. Also mucopolysaccharide storage diseases 2. Also glycosaminoglycan (GAG) storage diseases 3. Deficiency of specific enzymes involved in the degradation of mucopolysaccharides 4. Incompletely metabolized polysaccharide portions accumulate in the lysosomes of the connective tissue cells 5. Group of closely related syndromes which include a. MPS I (severe) – Hurler syndrome b. MPS I (attenuated) – Scheie syndrome c. MPS II – Hunter syndrome Page 4 of 18  d. MPS III – Sanfilippo syndrome e. MPS IV – Morquio syndrome 6. All autosomal recessive, except MPS II which is sex-linked recessive 7. PBS appears normal, metachromatic Reilly bodies may be seen 8. Diagnosis relies on assays for specific enzymes involved B. Lipidoses 1. Also lipid storage diseases 2. Result from the lack of a functional enzyme required for breakdown of lipids that have been ingested by phagocytes 3. All autosomal recessive except for Gaucher disease type II 4. Gaucher disease a. Most common lipidoses b. 3 types i. Type I – most common form; “adult” form ii. Type II – infantile or cerebral form; neurologic deterioration, death within first few years of life iii. Type III – juvenile form; life expectancy is short c. Clinical triad: hepatomegaly, Gaucher cells in BM, markedly elevated serum ACP d. Diagnostic biomarker is chitotriosidase e. Gaucher cell: monocyte/macrophage with fibrillar blue-grey cytoplasm with striated or wrinkled appearance (onion skin-like); strongly PAS (+) 5. Niemann-Pick disease a. Most prevalent form develops in infancy and resembles type II Gaucher disease b. Fatal within first few years of life c. Nieman-Pick cell: macrophage with a foamy or globular cytoplasm packed with lipid-filled lysosomes that appear as vacuoles after staining Gaucher disease Niemann-Pick disease Deficient enzyme β-glucosidase Sphingomylinase Macrophage Glucocerebrosides Sphingomyelin and cholesterol accumulates Cell appearance Crumpled tissue paper or Foam or bubble cell cigarette butt cell 6. Tay-Sachs disease a. Deficiency in hexominidase b. Accumulation of sphingolipids on lymphocytes c. Vacuolated and foamy lymphocytes d. High incidence in Ashkenazi, Jewish population e. No associated hematologic abnormalities 7. Sea blue histiocytosis a. Unknown enzyme deficiency b. Found in association with increased tissue stores of phospholipids/glycolipids c. Accumulation of histiocytes filled with lipid-rich granules in the spleen and BM; granules stain blue-green with Giemsa or Wright d. Characterized by hepatosplenomegaly and thrombocytopenia V. QUANTITATIVE DISORDERS OF LEUKOCYTES A. Leukemoid Reaction 1. Resemble blood findings in leukemia 2. WBC count >50 × 109/L or blasts forms are found in blood NLR (Neutrophil Leukemoid Reaction) CML (Chromic myelogenous leukemia) Reactive (patients with TB, metastatic tumor) Malignant (seen in CML) Involves only neutrophils Involves all granulocytes Rare blasts Occasional blasts Increased LAP score Decreased LAP score Plateletes may be increased with bizarre Normal platelet morphology and number forms B. Leukoerythroblastic Reaction 1. Aka leukoerythroblastic anemia and leukoerythroblastic anemia 2. Presence of immature neutrophils, nucleated RBCs and teardrop RBCs 3. Commonly associated with myelophthisis and primary myelofibrosis 4. Mild and transitory in hemolytic anemia, severe infections, cardiac failure, uremia and megaloblastic anemia Page 5 of 18 C. Neutrophilia and Neutropenia 1. Neutrophilia a. Mechanism: Increase outflow from BM and shift from marginal pool to circulating pool i. Infections – bacterial, fungal, spirochetes ii. Metabolic – uremia, gout iii. Physical/emotional – heat, cold, anger, pain iv. Tissue destruction – MI, burns v. Hormones – epinephrine, dexamethasone, cortisol (Cushing’s) vi. Hemolysis – hemorrhage vii. Drugs – corticosteroids, lithium 2. Neutropenia a. Decrease production i. Ineffective granulopioesis – megaloblastic ii. Myeloid hypoplasia – aplastic anemia, Swachman-Diamond syndrome, Kostmann anomaly b. Increase removal from blood i. Splenic sequestration – hypersplenism ii. Decreased survival – infections, brucellosis, salmonella, Autoimmune diseases, etc. c. Shift from circulating pool to marginal pool i. Drugs – anti-malarial drugs, benzene, sulphonamides 3. Left Shift a. Presence of increased numbers of circulating nonsegmented or immature neutrophils b. Circulating immature forms: i. Mild – band and metamyelocyte ii. Moderate – myelocytes and occasional promyelocytes iii. Marked – blast forms D. Eosinophilia and Eosinopenia 1. Eosinophilia a. Allergic diseases – asthma, allergic rhinitis b. Parasitic diseases – T. spiralis, Loeffler’s syndrome c. Myeloproliferative disorders – CML, polycythemia d. Chronic infections – fungal infections, Brucellosis, leprosy, tuberculosis e. Others – Hodgkin's disease, tumors 2. Eosinopenia a. Difficult to detect using routine diff. count b. Seen in: i. Decreased production – stem cell disorders ii. Acute bacterial infection iii. Stress (epinephrine) iv. Medications – steroid (dexamethasone); ACTH E. Basophilia and Basopenia 1. Basophilia a. CML b. Type I hypersensitivity reactions c. Allergic disease d. Hypothyroidism e. Polycythemia vera f. Ulcerative colitis g. Estrogen therapy h. Transient in NB infants and after exercise 2. Basopenia a. Acute infections b. Stress c. Hyperthyroidism d. Increased levels of glucocorticoids e. Difficult to diagnose because of their normally low reference range F. Monocytosis and Monocytopenia 1. Monocytosis a. Bacterial infection – TB, SBE, syphilis b. Inflammatory responses – surgical trauma, tumors, collagen disease, gastrointestinal disease c. Recovery from neutropenia (relative) d. Myeloproliferative disorders e. Autoimmune disorders – SLE, RA Page 6 of 18  f.Recovery stage from acute bacterial infections and recovery following marrow suppression by drugs 2. Monocytopenia a. Stem cell disorders – aplastic anemia b. After administration of glucocorticoids c. Overwhelming infections that also cause neutropenia G. Lymphocytosis and Lymphocytopenia 1. Lymphocytosis with Reactive Morphology a. Infectious Mononucleosis i. Caused by Epstein-Barr virus (EBV) ii. >20% AL (type II predominates) iii. Target cell are B cells (CD21), but AL are T cells! iv. Serology: Paul-Bunnel test (sRBC), rapid tests (horse RBC), IFA, antigen and antibody tests for VCA and EBNA (definitive test) b. Cytomegalovirus Infection i. with AL similar to IM; normocytic, normochromic anemia ii. Serology: IgG and IgM anti-CMV; negative heterophile antibody c. Toxoplasmosis i. Lymphoadenopathic variety of Toxoplasma gondii ii. Hematologic properties normal except for relative lymphocytosis with AL d. Miscellaneous Disorders: AL few days after onset of measles, mumps, chicken pox, hepatitis, and roseola 2. Lymphocytosis with Nonreactive Morphology a. Acute Infectious Lymphocytosis i. Children 1-10 years, viral or nonviral caused ii. Contagious, benign, and self-limited iii. Extreme leukocytosis; small lymphocytes b. Bordetella pertussis Infection: 70-90% lymphocytes c. Lymphocyte Leukemoid Reaction i. Resembles CLL ii. Chronic B. pertussis infection and IM in children 3. Lymphocytopenia a. Inherited: congenital immunodeficiency diseases (SCID, ataxia-telangiectasia, Wiskott- Aldrich, etc) b. Acquired i. Aplastic anemia infections (AIDS, hepatitis, influenza, herpes, TB, typhoid fever, sepsis, etc.) ii. Iatrogenic (immunosuppresive agents, chemotherapy, radiation, major surgery) iii. Systemic diseases (autoimmune dis., Hodgkin lymphoma, carcinoma, renal failure) iv. Nutritional/dietary (ethanol abuse, zinc deficiency) VI. LEUKEMIA A. General Information 1. A malignant leukocyte disorder 2. Abnormal, uncontrollable proliferation of one or more of the hematopoietic cells in the BM and blood 3. Etiology remains unclear 4. Involves oncogene activation, which includes the following factors: a. Viral – virus can suppress immune function or activate oncogenes (HTLV-I,II,V and HIV-1) b. Bone marrow damage – radiation, chemicals, malignancies secondary to cancer treatment c. Chromosomal defects d. Genetic factors – increased incidence in Down syndrome, fanconi, etc e. Immune dysfunction – hereditary and acquired defects 5. Aleukemic leukemia: uncontrolled malignant proliferation of WBC present in BM only (very rare) B. Pathophysiology of Leukemia Manifestation Reason Signs and Symptoms Leukemic cells outgrow normal WBC in BM; Sepsis, fever, severe infection, 1. Infection Leukemic cells are function less immunocompromised 2. Anemia Leukemic cells outgrow normal RBC in BM Pallor, pale, weak, tachycardia Leukemic cells outgrow megakaryocytes Easy bruisability, blleding, gums, 3. Bleeding and platelets in BM hemorrhage *Infection and bleeding are the major cause of death Page 7 of 18 C. Classification of Leukemia 1. Classified according to duration and predominant cell type 2. Majority of the patients in chronic leukemia go into blast crisis where they present an acute type of leukemia 3. Diagnosis of acute leukemia: a. Acute leukemia by FAB: >30% blasts in the BM b. Acute leukemia by WHO: >20% blast in the BM Acute Chronic Sudden onset Insidious onset Higher proliferative state Lower proliferative state Affects all ages Affects adults Survival is weeks to months without Survival is years without treatment treatment WBC count variable WBC count usually high Predominance of younger cells (blasts) Predominance of more mature WBCs Myeloid Lymphoid Myeloid Lymphoid Myeloblast T or B lymphoblast Myelocytes, T or B lymphocytes Promylocyte Metamyelocytes, Monoblast Stab, Neutrophils, Normoblast Eosinophils, Megakaryoblast Basophils, Monocytes, Platelets, RBC D. Malignancy 1. Growth and proliferation of one or more clones of abnormal cells 2. Malignant cells: a. may produce substances that inhibit the proliferation of normal cells b. may fill available space in the BM, inhibiting growth of normal cells E. Morphologic Evidence of Malignancy 1. Nuclear a. Shape abnormalities (clefting, contortions) b. Multinuclearity c. Megaloblastoid (nonresponsive to vitamin B12 or folate) d. Hyposegmentation (pseudo-pelger-huet) or hypersegmentation e. Giant or prominent nucleoli f. Increased mitotic figures 2. Cytoplasmic a. Abnormal granules (e.g., Auer rod) b. Mixed granulation (e.g., basophil and eosinophil) c. Decreased granulation d. Increased fragility (cytoplasmic fragmentation) 3. Overall a. Abnormal size (gigantism or dwarfism) b. Tendency to cluster or clump c. Clonal morphology (all abnormal cells appear similar) F. Hematopoietic Malignancy Classifications 1. French-American-British (FAB) Classification a. Based on cellular morphology and cytochemical stain results b. Divides the acute leukemia into Lymphoblastic (L1 to L3) and Myeloblastic (M0 to M7) c. Easier to use and is still widely used 2. World Health Organization (WHO) Classification a. Based on cellular morphology and cytochemical stain results b. Also utilizes information obtained from immunologic probes of cell markers, cytogenetics, molecular abnormalities and clinical syndrome c. Standard for diagnosis now G. Reactive Leukocytosis 1. Absolute count of granulocytes >8,000/uL 2. Etiology: a. Physiological stress – excessive cold or heat, exercise, postprandial, pregnancy, newborn, emotional states b. Infection – bacterial, rickettsial, parasitic, fungal c. Inflammation or tissue necrosis – MI, pneumonia, peritonitis, tumor necrosis d. Drugs Page 8 of 18  e. Metabolic – diabetic acidosis, gout f. Hematologic disorders – acute hemorrhage or hemolysis, myeloproliferative diseases g. Idiopathic 3. WBC count: a. 10,000 – 20,000/uL = consistent with inflammation or physiologic causes b. 20,000 – 50,000/uL = consider leukemoid reaction VS CML c. >100,000 = consistent with CML 4. Differential Diagnosis: a. Acute granulocytosis caused by physiologic stimuli is transient with no shift in marrow cellularity b. Increased # of nonsegmented PMN with increase in total # of granulocytes, or clinical symptoms suggestive of Pelger-Huet anomaly c. Left shift with nRBC and teardrop poikilocytes characteristic of leukoerythroblastic picture d. Granulocytosis and left shift with eosinophilia and basophilia suggests CML 5. Bone marrow a. Reactive granulocytosis – hypercellular (70-80%) BM with M:E ratio doubled (3:1) and left shift to myelocyte seen b. CML or other myeloproliferative disorder – shift to myeloblasts or promyelocytes; great increase in megakaryocytes or dyserythropoiesis VII. MYELODYSPLASTIC SYNDROME (MDS) A. General Information 1. Has also been called dysmyelopoietic syndromes (DMPS), refractory anemia, smoldering leukemia, oligoblastic leukemia 2. Also referred to as Preleukemia (may progress to acute nonlymphocytic leukemia) 3. Clonal hematopoietic neoplasms characterized by cytopenias due to ineffective hematopoiesis and increased apoptosis 4. Blood cytopenias despite BM hyperplasia. Characterized by a hypercellular BM and abnormality in the cellular maturation of the erythroid cells, granulocytes and megakaryocytes 5. Classic triad of symptoms a. Fatigue b. Fever – secondary to infection c. Bleeding – thrombocytopemia; petechiae or ecchymoses 6. Median survival: approximately 2.5 years 7. Only cure for MDS is BM or HSC transplantation B. Etiology 1. Primary MDS a. May arise de novo b. May be caused by chemicals (e.g. (benzene, toluene), radiation (x-ray), viral infection, smoking 2. Therapy-related MDS a. In patients previously treated with chemotherapy or radiotherapy or both b. At risk also are patients receiving cytokines (e.g. G-CSF, GM-CSF) c. More aggressive and may evolve quickly into AML C. Morphologic Evidence of Dyspoiesis* *abnormality in maturation 1. Dyserythropoiesis – hallmark of DMPS a. Karyorrhexis (nuclear fragmentation) b. Multinuclearity 2. Dysgranulopoiesis a. Pseudo-pelger-huet b. Retarded nuclear maturation 3. Dysmegakoryocytopoiesis a. Large and small megakaryocytes b. Giant platelets with abnormal platelet granules D. General Laboratory Findings 1. Dimorphic RBCs: macrocytic or microcytic/hypochromic anemia 2. Neutropenia, hyposegmentation of neutrophils, shift to the left, monocytosis 3. Variable platelet count, giant platelets, micromegakaryocytes 4. Deletion of a large portion of chromosome 5 (except in CMML) E. FAB Classification of MDS Based on BM and peripheral blood (PB) blast count and degree of abnormality in the three cell lines Page 9 of 18  1. Refractory anemia (RA) a. Also RC (Refractory cytopenia) b. Mildest form c. Anemia is refractory (not responsive) to therapy d. No dysgranulopoiesis and dysmegakaryopoiesis e. Laboratory findings: i. High MCV and RDW ii. Absolute reticulocytopenia iii. Megaloblastoid maturation in BM iv. Blast 30%) in BM and blood is the promyelocyte which is hypergranular b. Chromosome abnormality t(15-17), translocation involving chromosome 15 & 17 c. Frequently associated with DIC; abnormal promyelocyte release thromboplastin like substances; causes severe bleeding d. Laboratory findings: i. >30% promylocytea and >30% blasts in BM and PB ii. To distinguish from M2, in M3 granules are very numerous and obscure cytoplasmic basophilia iii. Auer rods plenty and in bundles (faggot cells) 5. M4: Acute Myelomonocytic Leukemia (AMML) a. aka Naegeli leukemia b. Predominant cell is myeloblast and monocyte (>20%) c. Granulocytic and monocytic differentaition in PB and BM d. Associated with soft tissue infiltrates (unlike M1 to M3) e. Gum hypertrophy and infiltration, rectal ulceration, skin involvement f. Laboratory findings: i. BM: nonerythroid cells – >30% blasts; >20% monocytic lineage; 30-80% myeloblasts, promyelocyte and other maturing granulocytic forms ii. PB: mostly blasts and abnormal cells, >20% monocytes and monocytes precursors g. M4Eo (Acute myelomonocytic leukemia with eosinophilia): same with M4 but may have up to 30% immature eosinophil in BM 6. M5: Acute Monocytic Leukemia (AMoL) a. Highest degree of skin and gum involvement due to migration of monocytes b. 80% monoblasts, promonocytes and monocytes, 50% erythroblasts with dyserythropoiesis, >30% myeloblasts ii. PB: numerous nRBC’s, immature granulocytes 8. M7: Acute Megakaryocytic Leukemia (AMegL) a. Rapid proliferation of megakaryoblasts and atypical megakaryocytes in BM; blasts may have cytoplasmic blebs b. Presents with pancytopenia and bleeding c. Laboratory findings: i. >30% megakaryoblast in BM ii. Blasts may have cytoplasmic blebs iii. PB: undifferentiated blast & megakaryocytic fragments G. Cytochemical Findings in AML SBB/MPO NASDA ANAE ANBE PAS Myelocytic (M1, M2, M3) Pos Pos Neg Neg – Myelomonocytic (M4) Pos Pos Pos Pos Monocytic (M5) Neg/ Weak/ Scattered pos Neg Pos Pos Pos Erythroleukemia (M6) – – Pos Neg Pos Megakaryocytic (M7) – – Pos Neg Pos 1. Sudan Black B (SBB) and Myeloperoxidase (MPO) – stains granulocytic and monocytic cells 2. Naphthol AS-D Chloroacetate Esterase (NASDA), a specific esterase – stains granulocytic cells 3. Alpha Naphtyl Acetate Esterase (ANAE), a nonspecific esterases – stains monocytic cells and megakaryocytes 4. Alpha Naphtyl Butyrate Esterase (ANBE) are nonspecific esterases – stains monocytic cells 5. (–) generally not performed IX. MYELOPROLIFERATIVE NEOPLASMS (MPNs) A. General Information 1. Also Chronic Myeloproliferative Disorders (CMPDs) a. “Chronic” – disorder of long duration; primarily affect middle-aged to older people with gradual onset; patients are in their fifth and sixth decades b. “Myeloproliferative” – abnormality arises in a pluripotential stem cell of the myeloid series 2. Proliferation of an abnormal myeloid pleuripotential stem cell that result in expansion, excessive production, and accumulation of erythrocytes, granulocytes, and platelets 3. Named for the cell line most greatly affected a. Chronic myelogenous leukemia (CML) – granulocytes b. Polycythemia vera (PV) – red cells c. Primary myelofibrosis (PMF) d. Essential thrombocythemia (ET) – platelets 4. Chronic MPDs (WHO) a. Chronic myeloid leukemia b. BCR-ABL1–positive CML c. Chronic neutrophilic leukemia (CNL) d. Polycythemia vera (PV) e. Primary myelofibrosis (PMF) f. Essential thrombocythemia (ET) g. Chronic eosinophilic leukemia, not otherwise specified (NOS) h. Mastocytosis i. Myeloproliferative neoplasm, unclassifiable B. Clinical Features 1. Mild to marked erythrocytosis, leukocytosis, and thrombocytosis 2. BM is hypercellular and may eventually become fibrotic 3. Presence of oncogenes (molecular diagnostics) a. JAK2 oncogene in PV (80%), chronic idiopathic myelofibrosis (50%) and ET (40%) b. BCR/ABL oncogene associated with CML Page 12 of 18  4. Splenomegaly/hepatomegaly due to extramedullary hematopoiesis 5. Acute leukemia (AML/ALL) is usually the end stage C. Chronic Myelogenous Leukemia (CML) 1. 20% of all leukemias 2. Also Chronic Granulocytic Leukemia (CGL) 3. Predominant proliferation of granulocytic series 4. Insidious onset, middle aged adult (30-50 year old) 5. Laboratory findings: a. Marked leukocytosis (WBC count 50 – 300 × 109/L) b. Prominent eosinphilia and basophilia, ↑APC c. Blood picture: complete spectrum of granulocytic cells in peripheral blood, from the myeloblast (90% cases) – fullness in upper abdomen c. Bleeding manifestations (thrombocytosis + platelet dysfunction) 7. Chronic phase can last up to 5 years; in the accelerated phase CML can convert to a terminal myeloblastic, lymphoblastic acute leukemia 8. Differentiation of CML and Leukemoid Reaction Parameter CML Leukemoid Reaction Peripheral Blood WBC Blasts/Promyelocytes Usually myelocytes Few cells younger Toxic granulation Absent Present Eosinophils/Basophils Increased Decreased Erythrocytes May have nRBC, Howell-Jolly bodies Less likely LAP Low to zero High Ph1 Usually present Absent Splenomegaly Usually prominent Mild if absent Parameter CML Leukemoid Reaction D. Polycythemia Vera 1. Panhyperplasia/panmyelosis: malignant hyperplasia of the multipotential myeloid stem cell cause an increase in all cell lines 2. Affects primarily the erythroid series with excessive proliferation of granulocytic and megakaryocytic cell lines 3. RBC mass is increased with normal plasma volume 4. Laboratory findings: a. Increased RBC (7-10 × 1012/L), hct, hgb, WBC and platelets b. Increased erythroid, granulocytic and megakaryocytic cell lines in BM c. Increased LAP d. Decreased EPO (negative feedback) and ESR 5. Increased blood viscosity leads to high BP, stroke, heart attack, intravascular thrombi, ruddy cyanosis E. Primary Myelofbrosis (PMF) 1. Aka agnogenic myeloid metaplasia, idiopathic myelofibrosis, myelofibrosis with myeloid metaplasia a. Agnogenic: of unknown cause b. Metaplasia: abnormal replacement of cells of one type by cells of another 2. Characterized by fibrosis in BM plus proliferation of granulocytic, erythrocytic and megakaryocytic series in spleen, liver and lymph nodes 3. Extramedullary hematopoiesis causes splenomegaly and hepatomegaly 4. Clinical features/ Laboratory findings: a. Mild anemia, becoming progressively severe b. BM is hypocellular and fibrotic – dry BM tap due to fibrosis (↑ fibroblasts) c. Tear drop RBC (dacryocyte) d. Leukoerythroblastic blood picture (nRBC + immature WBCs + abnormal platelets) Page 13 of 18  e. Defective platelets 5. PMF most commonly confused with CML. However in CML there are no high # of nRBC’s and dacryocytes F. Essential Thrombocythemia (ET) 1. Also Primary Thrombocythemia 2. Proliferation of megakaryocytes leading to increased platelets 3. Increase in platelet mass without accompanying significant erythrocytosis a. Platelet count = >600 × 109/L b. Hb = 1000 × 109/L APC b. Marked platelet anisocytosis c. Platelet aggregates in PB (spontaneous aggregation) with many giant and bizarre forms d. Abnormal platelet function = bleeding problems and thrombosis e. Leukocytosis f. BM: myelofibrosis, may simultaneously be hypercellular 6. Most commonly confused condition with ET is reactive thrombocytosis Essential thrombocythemia Reactive thrombocytosis Platelet count >1500 × 109/L Rarely >1000 × 109/L Bleeding Common Unlikely Platelet aggregation test Abnormal Normal G. Chronic Neutrophilic Leukemia 1. Rarest of the chronic MPDs 2. Laboratory findings: a. Neutrophilic leukocytosis without a left shift b. Normal to slightly decreased platelet counts c. Mild anemia d. Extremely high LAP score (350-400) e. Decreased CFU-C X. ACUTE LYMPHOBLASTIC LEUKEMIA (ALL) A. General Information 1. Most common of all leukemia 2. 75% of childhood leukemia 3. Most common malignant disease in children (2-10 years old) 4. Slow uncontrollable growth of abnormal lymphoid cells in the BM, spleen and lymph nodes B. Laboratory Findings 1. WBC count: 60 % >10 × 109/L; 15 % >100 × 109/L; 25 % 100 × 109/L) with >60% lymphoblast, frequently WBC may be normal or ↓ with fewer lymphoblasts 3. BM: hypercellular with lymphoid cells 4. Predominance of lymphoblasts in BM and CSF 5. Normocytic, normochromic anemia 6. Thrombocytopenia 7. Cytochemistry: (-) SBB, MPO and CAE; (+) TdT, ACP, NSE C. Clinical Manifestations 1. Most common symptoms: malaise, fatigue, pallor 2. Weight loss, fever, bone or joint pain 3. Splenomegaly and hepatomegaly 4. CNS involvement with scrotal infiltration 5. Petechiae, purpura and/or hemorrhage (secondary to thrombocytopenia) D. FAB Classification of ALL 1. ALL L1 a. Most common type (74%) of childhood leukemia b. May occur at any age; but peak incidence is at age 3 (2- to 10-year peak) c. Best prognosis, responds best to therapy 2. ALL L2 a. Accounts for 14% of childhood ALL b. 64% of adult ALL (most common in adults) 3. ALL L3 a. Burkitt type (Leukemic phase of Burkitt lymphoma) b. 3-5% of the case of ALL c. Prognosis is poor Page 14 of 18  4. Morphologic Differentiation of ALL L1 L2 L3 Size Very small and Larger and variable Large but varies little homogenous (heterogenous) in size with size Nucleus Round and regular in Clefted with nucleoli Round with 1-3 nucleoli shape with present inconspicuous nucleoli Cytoplasm Scanty (↑N/C ratio) Abundant, basophilic Moderate and deeply basophilic often with vacuoles E. Acute Leukemia Cytochemical Reaction Chart Condition MPO SBB NASDA ANBE ANAE ALL – – – –/+ –/+ AML + + + – – AMML + + + + + AMoL – –/+ – + + XI. CHRONIC LYMPHOPROLIFERATIVE DISORDERS (CLLD) A. General Information 1. Accumulation of clones of malignant lymphocytes in the blood, BM, lymph nodes or other organs 2. Accumulation is caused by reduced rate of cell death 3. Nearly all (99%) are clonal B-cell diseases 4. Three disease entities: a. Chronic Lymphocytic Leukemia (CLL) b. Prolymphocytic Leukemia (PLL) c. Hairy Cell Leukemia (HCL) B. Chronic Lymphocytic Leukemia (CLL) 1. Chronic disorder characterized by lymphadenopathy and infiltration of BM and peripheral blood by mature lymphocytes 2. More common in men, 40 to 60 years old 3. Median survival after diagnosis is 3-4 years 4. Clinical Symptoms: a. May be asymptomatic – diagnosis made accidentally from examination of peripheral smear; diagnosed secondary to other conditions b. Most common early signs: enlarged lymph nodes, splenomegaly (and hepatomegaly later) c. Most common presenting symptoms: fatigue and reduced exercise tolerance d. More advanced disease: marked fatigue, bruising, pallor, infections, bone tenderness, weight loss, edema e. Bacterial infection is the major cause of death f. AIHA in 10% of cases 5. Laboratory findings a. Lymphocytosis in BM and PBS i. Absolute count: 10-150 × 109/L ii. Predominant cell is small mature lymphocyte with coarse chromatin, inconspicuous nucleoli, and scant cytoplasm iii. Lymphocytes more fragile than normal (smudge cells) b. WBC count is 20-200 × 109/L c. Aggressive/advanced disease: granulocytopenia, anemia, or thrombocytopenia d. Majority of CLL involves the B lymphocytes (CD19, CD20 positive) e. Hypogammaglobulinemia 6. RAI classification – a system of 5 stages to allow clinical categorization of patients into prognostic group a. Stage 0 – absolute lymphocytosis (>15 × 109/L) in the peripheral blood and BM; has better prognosis (about 10 yrs.) b. 1 – includes enlargement of the lymph nodes c. 2 – + enlargement of the liver and spleen d. 3 – + anemia e. 4 – + thrombocytopenia C. Prolymphocytic Leukemia 1. Predominant cell in BM is prolymphocyte, 80% are of the B cell type 2. Male predominance, adults Page 15 of 18  3. Poor prognosis: respond poorly to treatment, average survival of 2 years 4. Laboratory findings: a. Marked lymphocytosis (100 × 109/L) and splenomegaly b. High WBC count (25-1000 × 109/L) D. Hairy Cell Leukemia 1. aka leukemic reticuloendotheliosis 2. A chronic, malignant, lymphoproliferative disorder characterized by pancytopenia 3. Characterized by hairy cells in the blood and BM (small B lymphocytes, has grayish cytoplasm that has hairlike projections around the outer border) 4. Mean survival is 5 years 5. Common in men, median age of 50 years 6. Laboratory Findings a. Pancytopenia – most consistent laboratory observation i. Leukopenia (granulocytopenia and monocytopenia) ii. Thrombocytopenia iii. Normocytic, normochromic anemia b. Dry tap on BM aspiration c. B cell malignancy (CD19, CD20, CD22 positive) d. Hairy cells in peripheral blood i. TRAP (+) – contains tartrate resistant acid phosphatase ii. May be few so need buffy prep to locate XII. LYMPHOMA A. General Information 1. Monoclonal neoplastic proliferation of one of the cellular components of the lymphoid system 2. A group of malignant tumors of the lymphoid tissues (lymph nodes and spleen); initially localized but may spread to BM and blood 3. Strongest risk factors is altered immune function as seen in immunocompromised and autoimmune disease patients 4. WHO groups the lymphomas into Hodgkin, B cell, and T/NK cell (Non-Hodgkin) neoplasms 5. Diagnosis through lymph node biopsy 6. Generally occurs in elderly individuals 7. WHO groups the lymphomas into: a. Hodgkin – 40% of lymphomas b. Non-Hodgkin (B cell, and T/NK cell neoplasms) – 60% of lymphomas 8. ALL and Lymphoma classified as same disease with different clinical presentations (WHO) a. Peripheral blood and BM involvement with >20% blasts define ALL b. Solid tumor presentation defines lymphoma B. Hodgkin’s Lymphoma 1. Has been shown to be of B-cell origin 2. Cells reacting to the neoplasms predominate rather than the neoplastic cells themselves 3. Male predominance with bimodal distribution (15-30 and >50 year old) 4. Most common finding are enlarged, painless, cervical lymph nodes 5. Laboratory findings: a. Distinguished from other lymphomas by the presence of Reed-Sternberg cell(s), a large binucleated/multinucleated cell, each nucleus has a large nucleolus (owl’s eye) b. Increased ESR, fibrinogen, gamma globulins and LAP c. High WBC with neutrophilia, eosinophilia and monocytosi 6. Classification of Hodgkin’s Lymphoma a. Rye classification/WHO classification Based on histologic appearance of lymph node biopsy; universally adopted i. Nodular sclerosis – 78%, lacunar cells ii. Mixed cellularity – 23% iii. Lymphocytic predominance – 7% iv. Lymphocyte depleted – 2% b. Ann Arbor classification Based on the location and extent of involved tissues Each stage is further divided into A(absence) or B (presence) of unexplained fever, night sweats and weight loss i. Stage I – involves single lymph node region ii. Stage II – >2 lymph nodes on one side of the diaphragm iii. Stage III – lymph nodes on both sides of the diaphragm and spleen iv. Stage IV – BM, liver and other extranodal sites Page 16 of 18  C. Non-Hodgkins Lymphoma 1. Proliferation of malignant lymphocytes that are arrested at certain stages of maturation (neoplasms of B cells and T/NK cells) 2. Enlarged lymph nodes (where the disease is primarily located), liver and spleen 3. Common in middle and older age group (50 years of age; frequently in males) 4. Mycosis Fungoides a. A T/NK neoplasm; rare lymphoma b. Most common cutaneous lymphoma c. Causes skin itching, leading to ulcerative skin tumors d. Lymphoid cells show a predilection for the epidermis (epidermotropism) and dermis and may spread to regional lymph nodes. 5. Sēzary syndrome a. Leukemic phase of mycosis fungoides (a variant of Mycosis Fungoides) b. Disseminated disease with widespread skin involvement (erythroderma), lymphadenopathy, and circulating lymphoma cells (Sézary cells) c. Characteristic tumor cell (sezary cell) in PBS resemble medium sized lymphocytes with a convoluted (cerebriform) nucleus resembling a monocyte d. As the disease infiltrates the lymph nodes, liver and spleen the prognosis becomes worse 6. Burkitt’s Lymphoma a. A B-cell neoplasm b. Translocation between chromosome 8 and 14 (in 90% of cases) c. Exact cause is unknown (EBV may transform B cells) d. Found most often in children in Africa and New Guinea e. Commonly affects the jaw and facial bones; in American children, it affects the lymph nodes in the abdominal, pelvic and neck areas (non-endemic variety) f. Tumor growth rate is the highest of any tumor (doubling each day) g. Rapid growth and tumor cell death results in “starry sky” appearance of biopsy caused by macrophage cleaning the dead cells h. Sensitive to chemotherapy with complete remission 7. Classification of Non-Hodgkin’s Lymphoma a. Rappaport Classification i. Well differentiated ii. Poorly differentiated iii. Histiocytic iv. Mixed histiocytic-lymphocytic b. National Cancer Institute (NCI) classification i. Low malignancies ii. Intermediate malignancies iii. High grade malignancies D. Hodgkin VS Non-Hodgkin Lymphoma Lymphoma Reed Sternberg Cell Incidence Spread Hodgkin Present Bi-modal Stepwise (Predictable) Non-Hodgkin Absent No pattern Unpredictable XIII.PLASMA CELL DYSCRASIA A. General Information 1. Also Plasma cell neoplasms, Paraproteinemias, Monoclonal gammopathy 2. Malignant proliferation of a monoclonal population of plasma cells that may or may not secrete detectable levels of a monoclonal immunoglobulin 3. Monoclonal gammopathy: increase of one specific type of Ig produced by one neoplastic clone of plasma cells B. Multiple Myeloma 1. aka plasma cell myeloma 2. Malignant proliferation of atypical & immature pasma cells occurring in the BM (10-95%) 3. Clinical symptoms: a. Main clinical finding is bone pain (bone lesions/fractures) b. Renal failure (BJP toxic to tubular epithelial cells) and bacterial infection are the major cause of death c. Defective coagulation (Ig binds to platelets, blocking receptor sites for coagulation factor); this results in prolonged bleeding Page 17 of 18  4. Laboratory findings a. BM plasma cells >30% b. Plasma cells and lymphocytes on blood smear c. Increased gobulin: excessive production of IgG (most common) or IgA (decreased production of other immunoglobulins) causes increased blood viscosity d. Marked rouleaux; ↑ ESR e. Blue background to blood smear f. protein electrophoresis shows an increase gamma band containing an M-spot which is composed of monoclonal CHONs g. Urine is (+) for Bence Jones protein (free Ig light chain – kappa or lambda) C. Waldenström Macroglobulinemia 1. Low grade lymphoma like disorder characterized by infiltration of BM with small, mature lymphocytes which produce macroglobulins (monoclonal IgM of HMW) 2. Increased macroglobulins produce “hyperviscosity syndrome” which causes neurologic symptoms, CHF, visual impairment, nose/gum bleeding 3. Lifespan: 2-4 years 4. Laboratory findings a. Marked rouleaux b. Increased ESR c. Blue background to blood smear d. Plasmacytoid lymphocytes, plasma cells and lymphocytes on blood smear Characteristic Multiple Myeloma Waldenstrom Bone Involvement Yes No Serum Viscosity ± ↑↑ Immunoglobulin IgG IgM D. Heavy Chain Disease (HCD) 1. Malignant proliferation of lymphoid cells which produce incomplete Ig 2. Cells produce heavy chains without the associated light chains 3. Most cases are fatal (remission in some patients) 4. Death usually follows from infection 5. Types: a. Alpha HCD – most common form; aka Mediterranean lymphoma; plasma cell infiltration of small intestines (severe malabsorption) and abdominal lymph nodes (usualy present as an abdominal mass) b. Gamma HCD – resembles lymphoma, common in the elderly c. Mu HCD – rare, usually found in CLL; vacuolated plasma cells in BM d. Delta HCD – resembles myeloma E. Plasma Cell Leukemia 1. Generally found as an acute terminal stage in multiple myeloma 2. PBS shows up to 90% plasma cells 3. Anemia and thrombocytopenia from BM failure due to plasma cell infiltration 4. Common in males, 50-60 year old.; mean survival is about 9 months FURTHER READING 1. Keohane, E. M., Smith, L. J., Walenga, J. M., Rodak, B. F. (2016). Rodak's hematology: Clinical principles and applications (5th ed.). St. Louis, MO: Elsevier. 2. McPherson, R. A., & Pincus, M. R. (2011). Henry's Clinical Diagnosis and Management by Laboratory Methods E-Book. Saunders. 3. Stiene-Martin, E. A., Lotspeich-Steininger, C. A., & Koepke, J. A. (1998). Clinical Hematology: Principles, procedures, correlations. Philadelphia: Lippincott-Raven. 4. Turgeon, M. L. (2012). Clinical hematology: Theory and procedures (5th ed.). Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins. (to include page number) Page 18 of 18