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‏Disorders of White Blood Cells and Lymphoid Tissues
‏The haemopoitic system produce all blood cells include their
‏precursors and their derivatives

‏The number of WBC in the peripheral circulation normally ranges from 5000-
‏10000 cell/ µl. of blood. About 50-70% of WBC is granulocytes (nutrophils, eosin, and
‏basophile) about 20-30% are lymphocytes and about 2%- 8% are monocytes.
‏Lymphopenias are much less common; they are associated with congenital
‏immunodeficiency diseases, or are acquired in association with specific clinical status,
‏such as treatment with corticosteroids.
‏Neutropenia= Granulocytopenia
‏A reduction in the number of granulocytes in blood is known as neutropenia.
‏Sever reduction in the number of granulocytes in the blood is known agranulocytes. Total
‏WBC count reduces to 1000 cell/ µl. In some cases the total WBC count reduce to 200-
‏300 cell/ µl. Reduction in the WBC number that leads to increase the susceptible to
‏infections which may be sever enough to cause death.
‏Etiology and pathogenesis
‏The mechanisms that cause neutropenia can be broadly divided into two
‏categories:
‏1). Defect in neutrophils production due to:
‏-Exposure to radiation -Cytotoxic drugs admistration

‏2). The removal of neutrophils from circulation is acceleration due to:
‏-Inflammation - Idiopathic
‏-Infection -Immune destruction
‏ -Splenomegaly (increase destruction neutrophils in spleen).
‏Clinical Symptoms:
‏The initial symptoms are malaise, chills, and fever, followed by marked weakness
‏and fatigue. Ulceration and necrotic infection of the buccal cavity, gum, throat and other
‏sites are the major problem.
‏Treatment:
‏In addition to removal the causative agent like drug, infection; current treatment
‏administration of recombinant haemopoitic growth factors such as granulocyte colony
‏stimulating factor (G-CSF) these factors stimulate neutrophils production by the bone
‏marrow.
‏Neoplastic Disorders of Haemopoitic System and
‏Lymphoid Tissues
‏The Neoplastic disorders include:
‏-Leukemias
‏-Lymphomas
‏-Multiple Myeloma
‏Leukemias
‏Leukemias are malignant tumors of the haemopoitic stem cells
‏characterized by diffuse replacement of bone marrow by neoplastic cells.
‏The leukemic cells proliferate mainly in bone marrow, circulate in the
‏blood and infiltrate in the spleen, lymph nodes,‏and other organs.
‏Classification:
‏Leukemias are classified according to the:

‏). Type of malignant cells i.e. the precursor of the malignant cells are either
‏Lymphogenic or myelogenic.
‏2). Their incidence i.e. either acute or chronic. In acute cases are characterized by
‏replacement of the bone marrow with immature cells and rapidly fetal.
‏So there are four types or class of leukemia these are:
‏1). Acute Lymphocytic Leukemia (ALL): This type of leukemia characterized by
‏accumulation of lymphoblasts. It occurs mostly in childhood with peak incidence between
‏2-7 years. Etiology of ALL is unknown, but cytogenetic studies reveal some abnormality
‏of chromosome number and structure may lead to produce ALL.
‏The pathogenesis of clinical disease in all relates to the progressive accumulation in the
‏bone marrow of lymphoblasts.
‏2). Chronic Lymphocytic Leukemia (CLL): It is the most indolent of all leukemia, most
‏often seen in old people "older than 50 years". The leukemic cells are B cells in 95% of
‏cases, but in rare cases 5% the leukemic cells are T cells. The T cell leukemias are much
‏more aggressive than the B cell CLL.
‏-The leukemic B cells fail to respond to antigenic stimulation i.e. unfunctional B
‏lymphocytes.
‏About 50% of patients have chromosomal abnormality.
‏Clinical Features: CLL is often asymptomatic. When symptoms are present, they are
‏nonspecific and include; easy fatigability, weight loss, and anorexia, increase
‏susceptibility to bacterial infection. Total leukocyte count may be increased only slightly
‏or may reach 200000 per microliter. Many patients live more than 10 years after
‏diagnosis.
‏3). Acute Myeloid Leukemia (AML): The leukemic cell is myeloid multipotential
‏haemopoitic stem cell. AML primarily affect adult. Its incidence increases steadily with
‏age, with the median age being 50 years. The etiology of AML is not known. The risk
‏factors include the following: toxic agents, radiation, genetic abnormalities, and
‏hematologic disorders.
‏4). Chronic Myeloid Leukemia (CML): CML affects adults between 25-60 years of age
‏and accounts for 15% to 20% of all cases of leukemia.
‏Clinical features:
‏Splenomegaly , the laboratory finding, there is marked elevation of the leukocyte
‏count commonly exceeding 100000 cell per microliter, the circulating cells are
‏predominantly neutrophils and myelocytes, but basophils and eosinophils are prominent,

‏about 50% of patients have thrombocytosis. The course of CML is one of slow
‏progression. Median survival is 3 years.
‏Lymphomas
‏Lymphomas are malignant neoplasms of cells native to lymphoid tissue (i.e.
‏lymphocytes and histiocytes and their precursors and derivatives).
‏Types of Lymphomas:
‏Hodgkin's Lymphomas = Hodgkin's Disease
‏It is a malignant neoplasm of lymphatic structures characterized by painless and
‏progressive enlargement of single lymph node or group of lymph nodes. More often
‏localized to a single axial group of nodes (cervical, mediastinal, para-aortic).
‏-Hodgkin's disease is somewhat more common in men than in women and in the
‏white than in blacks. The peak incidence in the late 20 years of age , a decrease in
‏frequency during the 4th and 5th decades, and a gradually increasing incidence after age of
‏50 years.
‏-Early and increased exposure to an unidentified agent of low oncogenic potential
‏may be important in its development.
‏-Young adults who have experienced Epstein- Bar virus infection (infectious
‏mononucleosis) have a threefold increased risk of developing Hodgkin's lymphoma.
‏-Genetic factors may play a role in developing.
‏-There is an increased incidence of HD in patients with immunodeficiency and
‏autoimmune diseases such as rheumatoid arthritis.
‏-Hodgkin's lymphoma originate within one area of the lymphatic system and if
‏unchecked will spread throughout the
‏ughout the lymphatic network (disseminate)
‏Hodgkin's lymphoma is characterized by the presence of distinctive neoplastic
‏giant cells called Reed- Sternberg (SR) cells admixed with a variable inflammatory
‏infiltrate.
‏-The Reed- Sternberg (RS) cell has abundant, slightly eosinophillic cytoplasm.
‏Particularly characteristic are two mirror image nuclei, each containing a large (inclusionlike) acidophilic nucleolus surrounded by a distinctive clear zone: together they impart an
‏owl-eyed appearance.
‏Signs and Symptoms:

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‏In early stages there is no systemic complication but the advanced stages there is
‏systemic complication like fever, night sweat, loss weight, fatigue, pruritis, and amemia.
‏In the advanced stages the liver, lungs, GIT, and CNS may be affected.
‏Diagnosis:
‏-Biopsy for histopathologic examination.
‏-CT scan.
‏-Radiologic visualization of abdominal and pelvic lymph nodes.
‏-Treatment: Radiation and chemotherapy are used in treating the disease.
‏Non Hodgkin's Lymphomas (NHL)
‏NHLs are malignant tumors originated in lymphoid tissue usually in the lymph
‏nodes (65%of cases) or in the lymphoid tissue of parenchymal organs (35%). It
‏characterized by multicentric in origin and spread early to various tissues throughout the
‏body specially the liver, spleen and bone marrow.
‏•NHLs are tumors of immune cells so it may origin in T, B cells or histiocytes
‏(macrophages of lymphoid tissues). Most NHLs (80-85) % are of B cell origin; the
‏remainders are in large T cell tumor. Tumors of histiocytes are quite uncommon.
‏•The neoplasmic cells of B cell origin may either aggregate as nodule or spread
‏diffusely in lymphoid tissue. Aggregation as nodule is called nodular lymphoma, while
‏diffusely spread called diffuse lymphoma.
‏•All T cell lymphomas are diffuse.
‏•Nodular lymphomas are indolent tumors with long survival but not curable.
‏•Diffuse lymphomas are aggressive tumors that are rapidly fatal unless treated, but
‏with appropriate therapy, many can be cured.
‏Burkitt's Lymphoma
‏This is a high grad tumor of B lymphocytes, clinically aggressive. In fact this
‏tumor is the most rapidly proliferative of all human tumors