WBC, LYMPH NODES, SPLEEN, AND THYMUS I Flashcards
normal hematopoiesis
definitive _____________ arise several weeks later in the mesoderm of the intraembryonic aorta/gonad/mesonephros region
definitive hematopoietic stem cells
normal hematopoiesis
formed elements of blood - ____,_____,____,_____, and _____ - have a common origin from HSCs, pluripotent cells that sit at the apex of a hierarchy of bone marrow progenitors
r,g,m,p,p
red cells
granulocytes
monocytes
platelets
progenitors
normal hematopoiesis
HSC’s have two essential properties that are required for the maintenance of hematopoiesis:
________ and ________
pluripotency
capacity of cell renewal
normal hematopoiesis
the marrow response to short term physiologic needs is regulated by hematopoietic growth factors through their effects on the committed progenitors
these growth factors are called ____________ because they were discovered by their ability to support the growth of colonies of blood cells in vitro
colony stimulating factors
normal hematopoiesis
_________ of hematopoietic origin are often associated with mutations that block progenitor cell maturation or abrogate their growth factor dependence
tumors
disorders of white blood cells can be classified into two broad categories: ______ in which there is expansion of leukocytes and ______ which are defined as a deficiency of leukocytes
proliferative disorders
leukopenias
neutropenia agranulocytosis
______ occurs in aplastic anemia, and a variety of infiltrative marrow disorders; in these conditions granulocytopenia is accompanied by anemia and thrombocytopenia
diseased states associated with ineffective hematopoiesis such as _______- and myelodysplastic syndrome in which defective precursors die in the marrow
suppression of HCS
megaloblastic anemia
neutropenia, granulocytosis
alterations in the ________- vary with cause. with excessive destruction of neutrophils in the periphery, the marrow is usually hypercellular due to a compensatory increase in granulocytic precursors
____- are a common consequence of agranulocytosis.
bone marrow
infections
_________ refers to an increase in the number of white cells in the blood
it is a common reaction to a variety of inflammatory states
leukocytosis
leukocytosis
_________ which are coarser and darker than normal neutrophilic granules represent abnormal azurophilic primary granules
_______ are patches of dilated endoplasmic reticulum that appear as sky-blue cytoplasmic “puddles”
toxic granules
dohle bodies
leukocytosis
at other times particularly in severe infections many immature granulocytes appear in the blood, mimicking a myeloid leukemia (_____ reaction)
leukemoid reaction
lymphadenities
_______ in the cervical region is most often due to drainage of microbes or microbial products from infections of the teeth or tonsils, while in the axillary or inguinal regions is most often caused by infections in the extremities
acute nonspecific lymphadenitis
chronic nonspecific lymphadenitis morphology
____________ is caused by stimuli that activate humoral immune responses
defined by the presence of large oblong germinal centers ( secondary follicles), which are surrounded by a collar of small resting naive B cells (the mantle zone)
follicular hyperplasia
chronic nonspecific lymphadenitis morphology
_________ is caused by stimuli that trigger T cell mediated immune responses such as acute viral infections (e.g., infectious mononucleosis)
__________ (also called reticular hyperplasia) is marked by an increase in the number and size of the endothelial cells that line lympathic sinusoids and increased numbers of intrasinusoidal macrophages
paracortical hyperplasia
sinus histiocytosis
_____________ is a reactive condition marked by cytopenias and signs and symptoms of systemic inflammation refered to macrophage activation
for this reason, it is also sometimes referred to as macrophage activating syndrome
hemophagocytic lymphohistiocytosis
