1. RADR 2217 Radiographic Pathology
Chapter 9
The Hemopoietic System

2. He·mo·poi·e·sis
(Variant of) Hematopoiesis: The production of all types of blood cells generated by a remarkable self-regulated system that is responsive to the demands put upon it.
hematopoietic system n. The bodily system of organs and tissues, primarily the bone marrow, spleen, tonsils, and lymph nodes, involved in the production of blood.

3. Objectives
Identify the major constituents of blood and describe the function of each constituent.
Specify the various blood types.
Explain the role of lymphatic systems in terms of immunity.
Describe the pathogenesis, prognosis, and signs and symptoms of disease processes with regard to the hemopoietic system.

4. Overview Anatomy and Physiology of Blood Imaging Considerations
Acquired Immune Deficiency Syndrome
Neoplastic Diseases

5. Anatomy and Physiology of Blood

6. Hemopoietic System Blood Lymphatic tissue Bone marrow Spleen
Components
Blood
Lymphatic tissue
Bone marrow
Spleen

7. Circulating Blood Components: Plasma Blood cells
55% of total blood volume
90% water
10% solutes
Proteins
Glucose
Amino acids
Lipids
Blood cells
45% of total blood volume
Erythrocytes
Leukocytes
Thrombocytes

8. Erythrocytes Red blood cells Small, biconcave disks
Transport via Hemoglobin
Transports oxygen & carbon dioxide to and from organs of the body
May contain antigens to determine blood type
Anemia: < 12 g/100ml; less than normal oxygen or carbon dioxide transportation
Hematocrit – lab test to determine total % of RBCs in blood volume

9. Life of Erythrocytes Formed by Hemocytoblasts
Red bone marrow
Live approximately 120 days
Aged RBCs are removed by the spleen, liver and the bone marrow.
Phagocytosis
Iron released & recycled in development of new RBCs
Bilirubin formed & excreted in bile

10. Blood Types Types Type O Type AB
O (no antigen)
A antigen
B antigen
AB antigen
Type O
Universal donor
Type AB
Universal recipient
Agglutination – clumping of RBCS when held together by antibodies

11. Rh Factor Discovered in blood of Rhesus monkey Types Rh positive
85% of population
Rh negative
Rh incompatibility requires immunization of mother prior to pregnancy (Rhogam shot)
The above is true with 2nd pregnancy and subsequent pregnancies. 1st pregnancy progresses normally.

12. Leukocytes White blood cells; larger than RBCs Granular or nongranular
Granular formed in red bone marrow may live 14 days
Nongranular formed in lymph system may live for years
WBCs “attack” & phagocytose foreign substances
Changes in number often indicate disease process
Usually per ml normal range

13. Thrombocytes “Platelets” Necessary for proper blood clotting
Respond within seconds to initiate coagulation
Formed in myeloid tissue within red bone marrow
Life span of 10 days

14. Lymphatic System
Subsystem of circulatory system
Assures immunity through production of lymphocytes and antibodies
Responsible for fat absorption from intestinal tract
Also responsible for manufacturing blood under certain circumstances

15. Lymphatic System Components
Lymphatic vessels – contain lymph (milky liquid substance)
Lymph nodes – small ovoid bodies (chained) along vessels
Filter particles & foreign materials from blood
Become enlarged when infection is present
Regions include neck, mediastinum, axillary, retroperitoneal, & pelvic areas

16. Spleen Part of lymphatic system Produces lymphocytes and plasma cells
Stores RBCs
Functions in phagocytosis
May be removed without detrimental effects
May rupture with abdominal trauma

17. Lymphocytes Mature cells are most important in development of immunity
Types
T lymphocytes (derived from thymus gland
B lymphocytes (derived from bone marrow)
Ingest foreign substances
Most radiosensitive blood cells
Work with macrophages to ingest foreign substances & process specific foreign antigens
Effect on organ transplants

18. Radiation Exposure
Can have a harmful effect on blood marrow and lymphoid tissue
Whole body dose of Gy (50-75 rad) causes detectable change in blood cells
Most radiosensitive blood cells:
Lymphocytes
Leukocytes
Thrombocytes
Radiation treatments may reduce patient immunity

19. Imaging Considerations

20. Imaging Considerations
Radiography - limited role in diagnosis & treatment of hemopoietic conditions (skeletal & chest helpful)
Abdomen CT - lymph node enlargement
CT & MRI -Central nervous system & bone marrow imaging

21. Imaging Considerations
Radiographer safety
Standard precautions imperative for blood borne pathogens
Gloves
Gown
Mask
Face Shield
Proper needle disposal
Handwashing !!

22. Acquired Immune Deficiency Syndrome

23. AIDS First recognized in 1981
Acquired Immune Deficiency Syndrome
First recognized in 1981
Caused by 2 related human immunodeficiency retroviruses (HIV-1 and HIV-2)
Presence of unusual opportunistic infections
Directly linked to increased incidence of malignancies
Most common disease associated with lymphocytopenia or lymphocyte depletion

24. Inhibits body’s response to presence of various diseases
HIV-1 and HIV-2
Inhibits body’s response to presence of various diseases
HIV-1
Identified in 1984
Paralyzes normal immune mechanisms in body
Results in severe immunosuppression (AIDS)
Responsible for most cases in Western Hemisphere
More virulent than HIV-2
HIV-2
Principal agent of AIDS in West Africa

25. HIV-AIDS Signs & Symptoms
Lymphadenopathy
Malaise
Fever
Joint pain
Weight loss
Nausea & vomiting
Diarrhea
Leukopenia
Anemia
Thrombocytopenia

26. HIV-AIDS
May affect anyone; most frequent in homosexual & bisexual men and IV drug users
Virus transmitted by sexual contact & exposure to infected blood & body fluids
One of most common infections is TB
Pneumocystis carinii and bacterial pneumonias are also common

27. Kaposi’s Sarcoma Most common malignancy in AIDS (25-30% of patients)
Also affects connective tissue
Most often affects
Skin
lymph nodes
GI system
Radiographically presents as hilar adenopathy, nodular pulmonary infiltrates, & pleural effusion
Endobronchial Kaposi’s is frequent

28. Neoplastic Disease

29. Multiple Myeloma
Disease of plasma cells resulting in cell proliferation
Unknown etiology & usually confined to bone marrow
Abnormal plasma cells produce large amounts of protein
Forms discrete tumors that weaken affected bone & disrupts normal renal function
Typically seen over 40 years of age

30. Multiple Myeloma
Most frequently affects pelvis, spine, ribs, and skull
90% have bone involvement
Patient presents with bone pain, anemia, fatigue, bleeding disorders, renal problems, hypercalcemia, recurrent bacterial infections
Poor prognosis with survival usually 2-3 years

31. Multiple Myeloma Imaging
Demonstrates
Punched-out, osteolytic regions
Diffuse osteoporosis
May demonstrate pathologic & vertebral compression fractures
MRI more useful in early stages of disease (30% bone loss needed for conventional)

32. Leukemia
Disease of leukocytes resulting in overproduction of white blood cells
Unknown etiology
May be associated with exposure to irradiation & certain chemicals; also with genetic defects & Epstein-Barr
May lead to
anemia
bleeding
infection

33. Leukemia Classified as acute or chronic
Account for 35% of all cancer deaths in children under 15 years
All forms require cell destruction by irradiation or antileukemic drug therapy
Bone marrow transplants may be attempted
Survival depends on complete remission
Radiography role is limited

34. Non-Hodgkin’s Lymphoma
Malignancy of lymph cells
Most common lymphoma
Incidence increases with age
Unknown etiology
Found in
Lymph nodes
Bone Marrow
Spleen
Liver
GI system

35. Non-Hodgkin’s Lymphoma
Patient presents with lymphadenopathy & possible anemia
Diagnosis with CT of abdomen & pelvis
Bone biopsy may be performed
Treatment includes chemotherapy & radiation therapy

36. Hodgkin’s Disease Type of lymphoma affecting lymphoid tissue
Node distribution is usually retroperitoneal
Unknown etiology
Commonly affects ages & those over 60
More often affects men

37. Hodgkin’s Disease
Patient presents with malaise, fever, anorexia, enlarged lymph nodes
Staged according to extent of disease most often with CT
Commonly treated with radiation & chemotherapy