White blood cells and their disorders

Dr K HamptonHaematologist

Royal Hallamshire Hospital

Normal white cells

• Mature cells circulate in blood

• Produced from immature precursor cells in the bone marrow, derived from stem cells.

• Rate of production under hormonal control by series of growth factors.

Neutrophils

• Most numerous white cell, lifespan 10 hours• Phagocytose and kill bacteria• Release chemotaxins and cytokines,

important in inflammatory response

• Lack of number or function results in recurrent bacterial infections

Monocytes

• Produced in bone marrow, transit through blood for 20 hours and enter tissues as macrophages

• Some become dendritic cells that present antigens to the immune system

Basophils

• Relatively rare in peripheral blood• Migrate to tissues to become mast cells• Contain granules of histamine• Surface IgE• Important in immunity and allergy

Eosinophils

• Also rare in peripheral blood• Impotant in inflammation and allergic

responses• Special role in protection against parasites

Lymphocytes

• Vital to immunity• Some generate antibodies against specific

foreign antigens, eg bacteria, viruses• Other have phenomenon of immunological

memory, generates immunity and allow vaccination

B lymphocytes

• Named after Bone marrow• Differentiate into plasma cells and produce

immunoglobulins when stimulated by expose to a foreign antigen

T lymphocytes

• Named after Thymus• Some are helper cells (CD4)• Some are cytotoxic cells (CD8)

• Aid B cells in antibody generation and also responsible for cellular or cell mediated immunity

Immunodeficiency

• Congential or acquired immunodeficiency very serious condition, often fatal

• Congenital immunodeficiency treated with bone marrow transplant or gene therapy

• HIV virus causes AIDS due to infecting CD4 lymphocytes and leads to opportunistic infections

Bacterial infections

• Result in neutrophilia: increase in neutrophils

• Engulf and kill bacteria• Failure results in overwhelming infection

• Can aid neutrophil response with G-CSF, a specific growth factor for neutrophils

Viral infections

• Response by lymphocytes• Generate immunoglobulins and memory

cells• Usually only have infection once• Severe infections like hepatitis B and

Meningococcus C can be prevented by vaccination: generates memory B cells

Acute leukaemia

• Proliferation of primitive precursor cells usually only found in bone marrow

• Proliferation without differentiation

• Replaces normal bone marrow cells, leads to: anaemia: palor and lethargy

neutropenia: infection thrombocytopenia: bleeding

Acute myeloblastic leukaemia (AML)

• Malignant proliferation of the precursor myeloblasts in the bone marrow

• Disease primarily of adults: 50% survive 5 years

• Treatment is with cyclical high dose chemotherapy and possibly bone marrow transplantation

Acute lymphocytic leukaemia(ALL)

• Malignant proliferation of the lymphoblast precursor cells in the bone marrow

• Disease primarily of childhood: 80% cure

• Treated with cyclical chemotherapy over 2-3 years, CNS specific treatmentTransplantation only if relapse

High grade lymphoma

• Classified as Hodgkins disease and Non-Hodgkins lymphoma (NHL)

• Disease usually of lymph nodes that spreads to liver, spleen, bone marrow and blood

• Needs aggressive curative chemotherapy

• Localised disease may be treatable with radiotherapy

Chronic leukaemia

• Malignant proliferation with differentiation

• Overproduction of mature cells, not precursor blast

• Untreated has better prognosis, hence called chronic, commoner in older age

Chronic lymphocytic leukaemia

• Proliferation of mature lymphocytes, usually B lymphocytes

• Lymphocytosis in blood, lymphadenopathy, splenomegaly

• Prognosis measured in years to decades, treatment with out patient chemotherapy

Chronic myeloid leukaemia

• Proliferation of mature myeloid cells: neutrophils, also basophils and eosinophils

• Philadelphia chromosome, t9:22 specific chromosomal translocation

• Can be cured by bone marrow transplantation in younger age group

Low grade leukaemia

• Chronic proliferation of mature lymphoid cells of lymph node origin

• Disease principally of elderly, survival years to decades

• Treatment, when necessary, = out patient chemotherapy

Multiple myeloma

• Malignant proliferation of plasma cells in bone marrow

• Plasma cells are B lymphocytes that produce immunoglobulin

• Myeloma has monoclonal immunoglobulin in serum and urine

Multiple myeloma

• Lytic lesions in bones, with pain or pathological fracture

• Hypercalcaemia with thirst, polyurea and confusion, due to bone resorption

• Hyperviscosity due to immunoglobulin

• Renal failure