Ch07

Diseases and Disorders of the Blood

leukocytes

white blood cells

serum and formed elements

2 main components of blood

RBCs, leukocytes, platelets

consists the formed elements

hemoglobin

carries oxygen from the lungs to tissues and carries CO2 from tissues to lungs, contained in the RBCs

neutrophils

WBC, responsible for non-specific immune response

lymphocytes

WBC, responsible for specific immunity against antigens

monocytes

WBC; leave the circulation, enter the surrounding tissue and become phagocytic

eosinophils

WBC, increased in allergic individuals

Basophils

WBC; least common, secrete histamine and heparin

platelets

essential for coagulation of blood and also called thrombocytes, survive 10 days

megakaryocytes

platelets are small fragments of cytoplasm that break from large cells called…

iron, folic acid, vitamin B12

essentials for erythropoiesis

erythropoietin

released by renal cells when oxygen levels fall and stimulates erythropoiesis

anemia of renal failure

decreased production of erythropoietin by the kidney

pernicious anemia

older age group, lack of intrinsic factor production by gastric cells

aplastic or hypoplastic

anemia due to radiation, viruses, or poisons

sickle cell trait

heterozygous for HbS

sickle cell anemia

homozygous for HbS, RBC shape changes to sickle shape under low oxygen conditions; stacking of sickle cells and obstruction of vessels

primary polycythemia

• increase in RBC production due to no obvious cause

• increased production of WBCs and platelets and some patients go on to develop leukemia

• treatment is medication to suppress the overactive bone marrow

secondary polycythemia

• when bone marrow compensates for for pulmonary conditions that have reduced oxygenation like pulmonary fibrosis and emphysema

• treatment is removal of blood

thrombocytopenia

decreased platelets by the bone marrow and a shortened lifespan

purpura

rash where blood cells leak into the skin or mucous membranes → skin has purplish color

petechiae

smallish purplish pinpoint spots in the skin due to thrombocytopenia

ecchymosis

larger hemorrhages into the skin

autoantibodies

primary thrombocytopenia is due to _____ if there is no underlying bone marrow disease

idiopathic thrombocytopenic purpura (ITP)

blood disorder characterized by a decrease in the number of platelets in blood → cause easy bruising, bleeding gums, internal bleeding

• caused by autoimmune reaction to one’s own platelets

hemostasis (coagulation)

thromboplastin catalyzed prothrombin → thrombin converts fibrinogen → fibrin

vitamin K

coagulation factors produced by the liver require…

hemophilia

• deficiency of coagulation factor VIII

• sex-linked, affects males

Von Willebrand disease

results from deficiency in von Willebrand protein

• deficiency of the protein causes low levels of factor VIII and presentation as a hemophiliac