DISORDERS OF BLOOD CELLS VESSELS CHAPTER 7 HEMATOPOIESIS

DISORDERS OF BLOOD CELLS & VESSELS CHAPTER 7

HEMATOPOIESIS • • Generation of blood cells Lymphoid progenitor cells = lymphocytes (WBCs) Myeloid progenitor cells = all other blood cells Red blood cells transport oxygen • Hemoglobin is the compound in RBCs to which oxygen attaches for transport from lungs to tissues • Synthesis depends on iron, vitamin B 12, vitamin B 6, & folic acid

WHITE BLOOD CELLS ACTIVE IN IMMUNITY AND INFLAMMATION • Hormones and inflammatory and immune molecule mediators stimulate production of WBCs & platelets • Leukocytes fight microbes & other invaders • Promote the repair process

LIFE SPAN OF BLOOD CELLS • • Varies, shorter life span than other tissues Rapid cell turnover RBCs have longest life out of blood cells Disease of blood cells are d/t early cell death or destruction • The number of WBCs, RBCs, & platelets in blood is a function of their life span and the rate of their production versus the rate of their loss

ANEMIA • Low hemoglobin in blood • Always a sign of some underlying condition • Diagnosis: • CBC • Look at RBCs for either: • Failed Bone marrow production • Hemorrhage or destruction • Treatment: • Replace RBCs • Identify cause and reverse it

SICKLE CELL DISEASE • Autosomal recessive genetic disorder of hemoglobin synthesis • Hemoglobin is molecularly defective and unstable • Causing early RBC death • Clinical and Pathologic findings: • • Obstruction of small blood vessels Anemia Hemolysis Infections

WHITE BLOOD CELL MALIGNANCIES • Myeloid malignancies • Myeloid cells-precursors of granulocytes, RBCs, and megakaryocytes • Examples: Acute or chronic myeloid leukemia • Lymphoid malignancies • Lymphoid cells: B, T, or natural killer lymphocytes • Example: Acute or Chronic lymphoid leukemia

ACUTE MYELOID LEUKEMIA (AML) • AML: Increased numerous of myeloblasts in bone marrow and blood • Occurs in all ages, common in adults over 50 years • Sudden onset, symptoms appear rapidly as bone marrow becomes packed with malignant cells • Symptoms: bone pain, lymphadenopathy, enlarged spleen & liver, neurologic defects • Diagnosis: >20% of bone marrow cells must be myeloblasts • Treatment: Chemotherapy,

CHRONIC MYELOID LEUKEMIA (CML) • Slow, progressive disease • Rare in children • Moves through 3 phases: • Indolent period • Accelerated phase-resistant to treatment, increase anemia and thrombocytopenia • Evolution into AML-infection and hemorrhage dangerous threats

ACUTE LYMPHOID LEUKEMIA (ALL) • Malignant proliferation of immature lymphocyte precursors • Usually B cells • Most common malignancy of children • Clinically same as AML

CHRONIC LYMPHOID LEUKEMIA (CLL) • Slow onset • Most patients asymptomatic, disease uncovered due to presence of another condition • Constitutional S/S: • Malaise, loss of appetite • Mild fever • Weight loss