White Cells Disorders

White Cell Disorders

•       Leukocytosis

•       Leukopenia

•       Leukemoid reaction

•       Leukemia

•       Myeloproliferative disorders

Leukocytosis is a raised white blood cell count (the leukocyte count) above the normal range

•       white blood cell count greater than 11,000/ mm3 (11.0 x 10⁹/L)

•       Common in a variety of reactive inflammatory states caused by microbial and nonmicrobial stimuli

•        Nonspecific and can be classified on the basis of the particular white cell series affected

Classification

•       Neutrophilia

•       Eosinophilia

•       Basophilia

•       Monocytosis

•       Lymphocytosis

Neutrophilia

•       Pathological

–      Acute bacterial infection (pyogenic organisms)

–      Inflammation

§  Myocardial infarction

§  Burns

–      Corticosteroid therapy

–      Leukemia

•       Physiological

–      Pregnancy

–      Severe exercise, stress

Eosinophilia

•       Parasitic infestation

•       Allergic disorders such as asthma, hay fever, allergic skin diseases (e.g., pemphigus, dermatitis herpetiformis)

•       Drug reactions

•       Certain malignancies (e.g., Hodgkin disease and some non-Hodgkin lymphomas)

•        Collagen vascular disorders and some vasculitides

•       Eosinophilic leukemia

–      Blast in blood or marrow

–      Cytogenetic or molecular evidence of an abnormal myeloid clone

•       Idiopathic hypereosinophilic syndrome

–      Release of contents of eosinophil graqnules results in damage to heart, lungs and other organs

Basophilia

•       Myeloproliferative disorder

–      Chronic granulocytic leukemia

Lymphocytosis

•       Tuberculosis

•       Brucellosis

•       Chronic lymphocytic leukemia

•       Typhoid

•       Pertussis

•       Infectious mononucleosis

•       Cytomegalovirus infection

•       Infectious hepatitis

Monocytosis

•        Tuberculosis

•       Bacterial endocarditis

•       Rickettsiosis

•        Malaria

•       Collagen vascular diseases

–      Systemic lupus erythematosus

•       Inflammatory bowel diseases

–      Ulcerative colitis

Leukopenia

•       Leukopenia results most commonly from a decrease in granulocytes

•        Lymphopenias are much less common

•       Neutropenia

•       A reduction in the number of granulocytes in blood is known as neutropenia

•       Total white cell count is reduced to 1000 cells/μL and in some instances to as few as 200 to 300 cells/ul

•        Affected persons are extremely susceptible to bacterial and fungal infections, which can be severe enough to cause death.

Neutropenia

•       Inadequate or ineffective granulopoiesis

–       Aplastic anemia

–      Leukemia

–       Cancer chemotherapy agents also produce neutropenia by inducing transient marrow aplasia

–      Accelerated removal or destruction of neutrophil

–       Immune-mediated injury to neutrophils (triggered in some cases by drugs)

–      Idiopathic

–      Increased peripheral utilization

–       overwhelming bacterial, fungal, or rickettsial infection

–      Sequestration and accelerated removal of neutrophils

–      Enlarged spleen

Lymphopenia

•        Congenital immunodeficiency diseases

•        Advanced human immunodeficiency virus (HIV) infection

•        Treatment with corticosteroids

Eosinopenia

•       Steroid administration

Monocytopenia

•       Hairy cell leukemia

Leukemoid reaction

•       Leukemoid reaction is an excessive leukocytic response which includes leukocytosis of 50,000/cumm or higher with many circulating immature leukocyte precursors.

•       Reaction of a healthy bone marrow to extreme stress, trauma, or infection

•       Depending on the predominant cell, leukemoid reactions may be neutrophilic, eosinophilic, lymphocytic

•       Leukemoid reaction may be seen in tuberculosis, chronic infection,malignant tumors, acute alcoholic hepatitis.

•       Leukemoid reactions may produce a blood picture indistinguishable from CML

•       Serum leukocyte alkaline phosphatase  (LAP) is elevated in leukemoid reaction, but is depressed in chronic myelogenous leukemia

Leukemia (CML)	Leukemoid Reaction
Leukocyte count : Increased	Increased; toxic granules
Basophilia	-
Erythrocyte count : usually decreased	Normal
Platelet count: increased or decreased	Normal
LAP score : decreased	Increased
Philadelphia chromosome: present	Absent
	Disappears when the inciting stimulus is removed

Neoplastic disorders of bone marrow

•       Neoplastic disorders of bone marrow hematopoietic cells can be grouped into three main categories:

–      Myeloproliferative disorders (MPD)

–      Myelodysplastic syndrome (MDS)

–      Acute leukemia

•       Acute leukemia: Malignant neoplasm with proliferation of malignant blast cells

•       MPD and MDS

–      Not clearly malignant

–      Autonomous neoplastic proliferation of hematopoietic precursors

–      In MPD pheripheral blood shows increase in erythrocytes, leukocytes and/ or platelets

–      MDS are characterised by peripheral blood cytopenia (except chronic myelomonocytic leukemia)

–      Both MPD and MDS have chronic or acute course and have the potential of evolving into acute leukemia

Definition

•       Acute leukemia

–      Stem cell disorders characterized by a malignant neoplastic proliferation and accumulation of immature hematopoietic cells in the bone marrow

•       Myeloproliferative disorders

–      Hyperproliferation of neoplastic myeloid progenitors that retain the capacity for terminal differentiation; as a result, there is an increase in one or more formed elements of the peripheral blood

MPD:  The neoplastic progenitors tend to seed secondary hematopoietic organs (the spleen, liver, and lymph nodes), resulting in hepatosplenomegaly (caused by neoplastic extramedullary hematopoiesis) and mild lymphadenopathy

–       Association of these disorders with mutated tyrosine kinases

–       Most patients with this disease subgroup fall into one of four diagnostic entities:

§  chronic myelogenous leukemia (CML)

§  Polycythemia vera (PCV)

§  Primary myelofibrosis

§  Essential thrombocythemia