ClinicalVeterinaryPathology PDF

Preview

Summary

Summary...

Description

LEUKOGRAM CHANGES 1. Left shift: presence of immature neutrophils in neutrophils; indicates severe inflammation a. Regenerative left shift: There is neutrophilia with increased numbers of band neutrophils (compared to reference intervals) 2. Toxic change: indicates inflammation and only evident in the neutrophil lineage. INDIVIDUAL LEUKOCYTES NEUTROPHILS - Released from marrow in an age-dependent manner, i.e., the most mature cells are released before less mature cells

INCREASED DECREASED NEUTROPENIA NEUTROPHILIA - Decreased numbers of neutrophils (absolute - An increased numbers of mature neutrophils (absolute numbers not percentages) number not percentages) - Most common cause is inflammation MECHANISMS: - Shift from marginating  circulating pool: (increased movement into tissue), particularly when there is evidence of neutrophil corticosteroids and epinephrine cause movement of neutrophils from the immaturity. - Increased release from bone marrow: o Inflammation: cytokines stimulate release of MECHANISM: - Shift from circulating  marginating pool: the storage pool of neutrophils (lower in occurs in acute endotoxemia. This shif ruminants) contributes to short-term (1-3 hrs) o Corticosteroid: can also cause the release of neutropenia seen afer initial exposure to some mature (not usually band) neutrophils endotoxins. from the post-mitotic storage pool in marrow - Decrease release from bone marrow: - Increased production by bone marrow (3-5 days): congenital or inherited defects in bone o Reponse to inflammatory cytokines marrow release in humans have called (inflammation), which stimulate granulopoiesis myelokathexis - Delayed apoptosis: - Increased migration into tissue: In response o Prolonged survivals of neutrophils can be seen to inflammatory cytokines and chemokines under some situations o Due to tissue inflammation (bacterial CAUSES: sepsi, tumor necrosis, abscess, - Include inflammation (either infectious or nonendotoxemia). Most common cause of infectious)  trauma, surgery, burns neutropenia particularly in cattle with - Exogenous or endogenous corticosteroids & severe acute inflammation (metritis, epinephrine. Immune-mediated diseases such as mastitis), which have decreased immune-mediated hemolytic anemia are associated marrow stores of neutrophils that they with neutrophilia due to actions of inflammatory can release in response to cytokines inflammation - Feature of several different leukogram patterns, including an inflammatory leukogram, stress leukogram and physiologic leukocytosis

LYMPHOCYTOSIS LYMPHOCYTES - Increase in absolute numbers not percentages of - Small, mature lymphocytes lymphocytes are the most common lymphocyte in CAUSE: 1. Physiologic lymphocytosis peripheral blood o An epinephrine response, cats and horses, and - Feature: dense, round to slightly indented nucleus in young animals that results in a transient lymphocytosis of mature cells with smooth (clumped or blocky chromation), a 2. Physiologic due to youth o Young animals (...