Chapter 7

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Chapter 7

Blood and Blood-Forming Organs Diseases and Disorders

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Anatomy and Physiology

• Hematologic system• Major functions of blood:

– Transport nutrients to cells– Aid removal of wastes

• Average adult has 5 to 6 liters of circulating blood


Blood Components



• Erythrocytes– Normal count:

• 4.2 to 6.3 million

– Life span:• 120 days

– Form in bone marrow and do not reproduce



• Hemoglobin important in oxygen transport• Normal hemoglobin:

– Male• 13.5 to 18 hemoglobin in grams (gm)/100 milliliter (ml)

– Female• 12 to 16 gm/100ml



• Leukocytes protect individual from infection– Normal count:

• 4,500 to 11,000



• Platelets– Also known as thrombocytes– Important in blood clotting– Normal count:

• 150,000 to 350,000



• Blood-forming organs:– Lymph nodes– Bone marrow– Spleen– Liver

• Lymph system protects against pathogens



• Bone marrow– Major blood cell producer

• Spleen produces lymphocytes, plasma cells, and antibodies to filter microorganisms from blood

• Liver produces prothrombin and fibrinogen for blood clotting


Animation

Click Here to Play Blood Animation


Common Signs and Symptoms

• Erythrocytopenia– Decrease in RBCs leading to anemia– Symptoms:

• Fatigue• Headache• Low RBCs• Pallor• Shortness of breath



• Erythrocytosis– Increased RBCs– Symptoms:

• High RBCs• Reddened skin tones• Bloodshot eyes• Increased blood volume and pressure• Increased blood volume of heart



• Leukocytopenia– Decreased white blood cells– Weakens immune system

• Leukocytosis– Increased white blood cells– Normal response to acute infections



• Thrombocytopenia– Decreased platelet count leading to coagulation problem– Symptoms:

• Petechiae– Small hemorrhages in skin

• Ecchymoses– Large areas of bruising or hemorrhage



• Thrombocytopenia– Symptoms:

• Epistaxis– Nosebleeds

• Bleeding in mouth, gums, and mucous membranes



• Thrombocytosis– Increase in platelets– Uncommon– Usually no serious side effects


Diagnostic Tests

• Complete blood count with differential and indices

• Biopsy of blood-forming organs• Hematocrit (Hct) reflects amount of red cell

mass as proportion of whole blood• Hemoglobin (Hgb) reflects blood’s oxygen-

carrying potential


Diagnostic Tests

• Bleeding time determines platelet disorders– E.g., hemophilia, thrombocytopenia, disseminated

intravascular coagulation

• Prothrombin time (PT) and partial prothrombin time (PTT) measure blood’s ability to clot


Diagnostic Tests

• Biopsy– Bone marrow– Lymph node


Disorders of Red Blood Cells

• Anemia– Decrease in oxygen-carrying ability of RBC– Symptoms:

• Pallor• Fatigue• Shortness of breath



• Anemia– Symptoms:

• Tachycardia• Headache• Irritability• Syncope



• Iron deficiency anemia– Loss of iron or inadequate intake of iron– Causes:

• Blood loss• Low dietary intake

– Treatment:• Increase dietary intake of iron



• Folic acid deficiency anemia– Folic acid needed for maturation of RBCs– Causes:

• Poor diet• Overcooking of vegetables• Over consumption of alcohol

– Treatment:• Increase folic acid intake by eating green and yellow vegetables



• Pernicious anemia– Lack of intrinsic factor leading to inadequate absorption of

vitamin B12

– Treatment:• Monthly injections of vitamin B12 for life



• Hemolytic anemia– Destruction of RBCs related to antibody-antigen reaction– Disorder of immune system leading to destruction of

erythrocytes– Treatment:

• Exchange transfusion and/or splenectomy



• Sickle cell anemia– Hereditary– Found in African American race– Abnormal sickle shape of erythrocyte

• Does not allow cell to travel smoothly through vessels

– Symptomatic treatment– No cure



• Aplastic anemia– Failure of bone marrow to produce blood components– Causes:

• Chemotherapy• Radiation• Viruses• Toxins



• Aplastic anemia– Treatment:

• Avoid causative agent• Bone marrow transplantation• Transfusions



• Polycythemia– Too many blood cells– Symptoms:

• Enlarged spleen• Reddened mucous membranes• Bloodshot eyes• Deep red color on palms



• Polycythemia– Treatment:

• Donate blood at regular intervals to reduce blood volume


Disorders of White Blood Cells

• Mononucleosis– Also known as kissing disease– Symptoms:

• Fatigue• Sore throat• Swollen glands



• Mononucleosis– Diagnosis by increased monocytes in white blood cells

(WBCs)– Treatment:

• Rest• Analgesics• Throat gargles



• Leukemia– Malignant neoplasm of blood-forming organs– Abnormal production of immature leukocytes– May be acute or chronic– Acute forms affect children, progress rapidly, and may be

fatal



• Leukemia– Chronic forms affect older adults, are often asymptomatic,

and may not be fatal– Classified as:

• Myelogenous– Affecting bone marrow

• Lymphocytic– Affecting lymph nodes



• Leukemia– Diagnosis by bone marrow biopsy– Symptoms:

• Fatigue• Headache• Sore throat



• Leukemia– Symptoms:

• Dyspnea bleeding of mucous membranes of mouth and gastrointestinal (GI) system

• Bone and joint pain• Enlargement of lymph nodes, liver, and spleen

– Infections common



• Leukemia– Treatment:

• Aggressive chemotherapy• Once in remission, bone marrow transplant to replace neoplastic

tissue with normal tissue• Remission at 50 percent



• Hodgkin’s disease– Most common lymphoma– Symptoms:

• Painless enlargement of lymph nodes in neck• Weight loss• Fever

– Primarily affects young adults• Average age of 35



• Hodgkin’s disease– Cause thought to be viral– Diagnosis by presence of Reed-Sternberg cell in lymphatic

tissue– Treatment:

• Radiation• Chemotherapy

– If in remission for five years or more, complete cure possible



• Non-Hodgkin’s lymphoma (NHL)– Lymphomas lacking Reed-Sternberg cell– Symptoms:

• Painless enlargement of lymph nodes of neck, axilla, and inguinal areas

• Fever• Night sweats• Weight loss



• Multiple myeloma– Malignant neoplasm of plasma cells or B-lymphocytes– Increases with age

• Peaks in 70s

– Plasma cells multiply abnormally in bone marrow• Causes weakness• Leads to fractures and bone pain


Multiple Myeloma



• Multiple myeloma– Diagnosis by honeycombed bone pattern, hypercalcemia,

Bence-Jones protein found in blood and urine, and bone marrow biopsy

– Treatment:• Chemotherapy• Radiation• Not effective

– Poor prognosis


Disorders of Platelets

• Hemophilia– X-linked hereditary bleeding disorder– Several types

• Type A– Most common

– Male children from asymptomatic mothers– Lack protein necessary for clot formation



• Hemophilia– Symptoms:

• Epistaxis• Bruising• Prolonged bleeding

– Diagnosis by blood test



• Hemophilia– Treatment:

• Prevention of injury• Treat symptoms• Blood transfusions• Concentrated form of clotting protein

– No cure



• Thrombocytopenia– Also known as thrombocytopenia purpura– Decrease in platelets leading to inability to normally clot

blood– Symptoms:

• Abnormal bleeding in skin, mucous membranes, and internal organs

• Petechiae



• Thrombocytopenia– Symptoms:

• Ecchymoses• GI hemorrhages• Epistaxis• Hematuria



• Thrombocytopenia– Diagnosis by platelet count and bleeding time– Treatment:

• Avoid tissue trauma to reduce bleeding• Vitamin K• Transfusions of platelets• Splenectomy



• Disseminated intravascular coagulation (DIC)– Abnormal clotting followed by abnormal bleeding– Usually follows major trauma

• E.g., complicated childbirth, surgery, tissue destruction, septicemia, snakebite, shock

– Multiple clots in capillaries– Life-threatening



• DIC– Symptoms:

• Petechiae• Ecchymosis• Hematoma• Hematuria• GI bleeding



• DIC– Symptoms:

• Hematemesis• Blood in stool

– Treatment:• Heparin• Platelets



• Rare diseases– Thalassemia

• Primarily affects people of Mediterranean descent• Fragile, thin RBCs form defective hemoglobin



• Rare diseases– von Willebrand’s disease

• Hereditary• Congenital• Deficiency in clotting factor and platelet function• Also known as angiohemophilia• Affects females and males


Effects of Aging

• Age-related changes in other systems (e.g., immune, digestive) leave older adults more susceptible to infections and nutritionally related blood disorders

• Decreased iron• Poor nutrition

Education

Chapter 7