Disorders of WBC & Lymphoid tissues Flashcards
Hematopoiesis
*WBCs are formed partially in the bone marrow and partially in the lymph system
-formed from hematopoietic stem cells that differentiate into committed progenitor cells -> turns into myelocytic and lymphocytic lineages needed to form WBC
RBCs and platelets are formed in…
the marrow and released into circulation
Growth and reproduction of WBCs
*controlled by multiple hematopoietic growth factors or inducers
*life span is short, constant renewal is necessary to maintain normal blood levels
*conditions that decrease stem cells or hematopoietic growth factors produce a decrease in WBCs
Diseases of deficient blood cell production
*Leukopenia deficiency of leukocytes
-neutropenia
-granulocytopenia
*Aplastic anemia
-anemia, thrombocytopenia, and agranulocytosis
Causes of neutropenia
-accelerated removal
-drug-induced granulocytopenia
-periodic or cyclic neutropenia
-neoplasms involving bone marrow
-idiopathic neutropenia occurring in the absence of other disease or provoking influence
-Felty syndrome
Signs and symptoms of neutropenia
*Initially, those of bacterial or fungal infections
-malaise
-chills
-fever
-extreme weakness and fatigue
*reduced WBC count
Infectious mononucleosis
self-limited lymphoproliferative disorder
Causes of infectious mononucleosis
*caused by the B-lymphoproliferative EBV, a member of the herpes virus family ; transmitted in saliva
characteristics of infectious mononucleosis
*Characterized by fever, genialized lymphadenopathy, sore throat, and the appearance in the blood of atypical lymphocytes and several antibodies
-highest incidence in adolescent children and young adults
-treatment is symptomatic and supportive
Neoplastic disorder of hematopoietic and lymphoid origin
*represent the most important of white cell disorders
include somewhat overlapping categories
*Lymphomas
*Leukemia
*Plasma cell dyscrasias (multiple myeloma)
clinical features of neoplasms
*largely determined by
-their site origin
-the progenitor cell from which they originated
-the molecular events involved in their transformation into a malignant neoplasm
Chromosomal aberrations
deletions, polyploidy, translocations, hyper ploidy, inversions
Hodgkin disease
*lymphoma arises in a single node or chain of nodes
-Reed-Sternberg cells are present (cells derived from B lymphocytes)
Non-Hodgkin disease
*lymphoma originates at extranodal sites and spread to anatomically contiguous nodes
-Reed-Sternberg cells are not present
Symptoms of Hodgkin disease
*Stage A- lack of constitutional symptoms
*Stage B- (40% of persons with Hodgins disease) significant weight loss, fevers, pruritis, or night sweats
*Advanced stages- fatigue and anemia;
liver, lungs, digestive tract , and CNS may be involved
Categories of Non-Hodgkin lymphomas
*Low-grade lymphomas
-predominantly B-cell tumors
*Intermediate-grade lymphomas
-include B-cell and some T-cell lymphomas
*High-grade lymphomas
-largely immunoblastic (B cell), lymphoblastic (T cell), Burkitt, and non-Burkitt lymphomas
Diagnosis of Hodgkin Disease
*Reed-Sternberg cell present in a biopsy specimen of lymph node tissue
*CT scans of the chest and abdomen to assess for involvement of mediastinal, abd, and pelvic lymph nodes
*A bipedal lymphangiogram to detect structural changes in the lymph nodes too small to visualize on CT scan
*A PET imaging
*A bilateral bone marrow biopsy may be performed if disease is disseminated
Stages of Non-Hodgkin lymphomas disease
*Bone marrow biopsy
*Blood studies
*Chest and abdominal CT scans
*Nuclear medicine studies
*Cytologic examination of the cerebrospinal fluid
Treatment for Hodgkin and NHL
*Depends on the histologic type, stage of the disease, and clinical status of the person
*Types
-radiation
-combo chemo
-for NHL only (adjuvant radiation therapy, monoclonal antibodies)
Leukemias
malignant neoplasms arising from the transformation of a single blood cell line derived from hematopoietic stem cells
Classifications of leukemias according to cell lineage
*lymphocytic (lymphocytes)
*Myelocytic (granulocytes, monocytes)
Chronic leukemias
*Malignancies involving the proliferation of well-differentiated myeloid and lymphoid cells
Types:
Chronic lymphocytic leukemia (CLL)
Chronic myelogenous leukemia (CML)
Classification of Leukemia types
*Acute lymphocytic (lymphoblastic) leukemia (ALL)
*Chronic lymphocytic leukemia (CLL)
-Both involve immature lymphocytes and their progenitors in the bone marrow, the spleen, lymph nodes, CNS, and other tissue
*Acute myelogenous (myeloblastic) leukemia (AML)
*Chronic myelogenous leukemia (CML)
-Both involve the pluripotent myeloid stem cells in bone marrow and interfere with the maturation of all blood cells
Goals of treatment for CML
*A hematological response characterized by normalized blood counts
*A cytogenetic response demonstrated by the reduction or elimination of the Ph chromosome from the bone marrow
*A molecular response confirmed by the elimination of the BCR-ABL fusion protein
