DISORDERS OF WBCS AND LYMPHOID TISSUE

 Hematopoietic and Lymphoid Tissues 

• Main function of leukocytes (white blood cells): fight infection 

• Normal range for WBC is: 4000-10,000

• The Hematopoietic System 

  • Myeloid or bone marrow tissue 

    • Site in which WBCs are formed 

    • Leukocytes originate from pluripotent stem cells in the bone marrow 

  • Lymphoid tissue of the lymph nodes, thymus, and spleen 

    • Sites where WBCs circulate, mature, and function 

 

Main function of leukocytes?

fight infection 

What is the normal range for WBC?

4000-10,000

The Hematopoietic System 

• Myeloid or bone marrow tissue 

  • Site in which WBCs are formed 

  • Leukocytes originate from pluripotent stem cells in the bone marrow 

• Lymphoid tissue of the lymph nodes, thymus, and spleen 

  • Sites where WBCs circulate, mature, and function 

What is being described?

1. Site in which WBCs are formed 

2. Leukocytes originate from pluripotent stem cells in the bone marrow 

Myeloid or bone marrow tissue 

What is being described?

• Sites where WBCs circulate, mature, and function 

Lymphoid tissue of the lymph nodes, thymus, and spleen 

Hematopoiesis 

• WBCs form when stem cells differentiate into lymphoid stem cells or myeloid stem cells, then further differentiate into different types of each (lymphocytic or myelocytic) 

• WBCs have a short lifespan. Therefore, constant renewal is needed to maintain adequate blood levels. 

• Conditions that decrease the availability of stem cells or hinder their growth can lead to a decrease in WBCs. 

Non-Neoplastic Disorders of WBCs 

• Low WBCs

• Infections mononucleosis

 Non-Neoplastic Disorders of WBCs:

Low WBCs

• Leukopenia: Decrease in absolute number of leukocytes in the blood 

  • May affect any type of WBC, but most commonly affects neutrophils 

• Neutropenia:  

  • Neutrophil count < 1,000____ 

  • Agranulocytosis- most severe form of neutropenia. Neutrophil count is < 200 cells/ μL (virtual absence of neutrophils) 

• Many potential causes: 

  • Congenital 

  • Autoimmune disease 

  • Bone marrow depression 

  • Chemotherapy and/or radiation 

  • Hematologic malignancies 

  • Medications 

  • Severe infections 

  • Viral infections 

• Manifestations 

  • Increased risk of _____infection_________ 

  • Look like signs and symptoms of infection, mimic the s/s of infection 

  • Fever, chills, fatigue 

  • Potential death 

• HIGH RISK FOR INFECTION!

What is the…

• Decrease in absolute number of leukocytes in the blood 

  • May affect any type of WBC, but most commonly affects neutrophils 

leukopenia

What is being descibed here?

• Neutrophil count < 1,000____ 

• Agranulocytosis- most severe form of neutropenia. Neutrophil count is < 200 cells/ μL (virtual absence of neutrophils) 

neutropenia

What is Agranulocytosis

most severe form of neutropenia. Neutrophil count is < 200 cells/ μL (virtual absence of neutrophils) 

What are causes of neutropenia?

• Congenital 

• Autoimmune disease 

• Bone marrow depression 

• Chemotherapy and/or radiation 

• Hematologic malignancies 

• Medications 

• Severe infections 

• Viral infections 

Manefestations of neutropenia:

• Increased risk of infection

• Look like signs and symptoms of infection, mimic the s/s of infection 

• Fever, chills, fatigue 

• Potential death 

What is infectious mononucleosis?

1. Also called “Mono” or “The Kissing Disease” 

2. Self-limiting viral disease( means you’re going to get sick and then eventually you’re going to get better, “run its course”) 

3. Causative agents: 

   1. Epstein-Barr virus (Most common- 90%)- member of the herpesvirus family 

   2. Cytomegalovirus (CMV) (~10%) 

4. Transmitted via oral secretion 

5. More common in adolescents and young adults

 

6. Pathogenesis: 

   1. Virus invades B lymphocytes 

   2. Incubation period for 4 – 6 weeks (person may be asymptomatic) 

      1. Time between when you got the virus and you start having symptoms  

   3. Followed by malaise, anorexia, and chills (several days) 

   4. Abrupt onset of high fever usually occurs, along with severe pharyngitis(sore throat) 

   5. Typically lymphadenopathy (enlarged lymph nodes) in cervical, axillary, and groin areas 

   6. Increase in WBC 

   7. May have a rash and/or splenomegaly 

   8. Most people recover on their own (self-limiting) after about 2 – 3 weeks, but may not feel well for 2 – 3 months 

What is the Causative agents of Infectious Mononucleosis 

1. Epstein-Barr virus (Most common- 90%)- member of the herpesvirus family 

2. Cytomegalovirus (CMV) (~10%) 

Infectious Mononucleosis Pathogenesis

1. Virus invades B lymphocytes 

2. Incubation period for 4 – 6 weeks (person may be asymptomatic) 

   1. Time between when you got the virus and you start having symptoms  

3. Followed by malaise, anorexia, and chills (several days) 

4. Abrupt onset of high fever usually occurs, along with severe pharyngitis(sore throat) 

5. Typically lymphadenopathy (enlarged lymph nodes) in cervical, axillary, and groin areas 

6. Increase in WBC 

7. May have a rash and/or splenomegaly 

8. Most people recover on their own (self-limiting) after about 2 – 3 weeks, but may not feel well for 2 – 3 months 

Neoplastic disorders of Hematopoietic and Lymphoid Origin 

• malignant lymphomas

  • Non-Hodgkin Lymphoma 

  • Hodgkin Lymphoma 

• leukimas

• multiple myeloma

What are Malignant Lymphomas 

• Malignant Lymphomas 

  • Diverse group of solid tumors composed of neoplastic lymphoid cells 

  • B and T lymphocytes 

  • Two types: 

    • Non-Hodgkin Lymphoma 

    • Hodgkin Lymphoma 

Hodgkin Lymphoma	Non-Hodgkin Lymphoma
-Presence of Reed-Sternberg Cell* (diagnostic hallmark of the disease)    -Cause: Unknown; possibly exposure to carcinogens or some viruses; possible genetic or immune mechanisms	-Absence of Reed-Sternberg Cell      Cause: Unknown
Manifestations:  Painless, progressive enlargement of one lymph node or group of lymph nodes*  Typically above the level of the  diaphragm  Pruritis(itchy skin)*  Intermittent fevers/chills with night sweats*  Unintentional weight loss	Manifestations:  Lymphadenopathy (enlarged, painless lymph nodes)- widespread  Unintentional weight loss  Night sweats & fever  Increased risk for infection  Can be multiple lymph nodes
Originates in one area of lymph system but can spread to entire lymphatic system and any tissue/organ if left untreated    Treatment = 98% survival rate	Survival rate ~ 75%

 

what is being descibed?

-Presence of Reed-Sternberg Cell* (diagnostic hallmark of the disease) 

 

-Cause: Unknown; possibly exposure to carcinogens or some viruses; possible genetic or immune mechanisms 

Manifestations: 

• Painless, progressive enlargement of one lymph node or group of lymph nodes* 

• Typically above the level of the diaphragm 

• Pruritis(itchy skin)* 

• Intermittent fevers/chills with night sweats* 

• Unintentional weight loss 

-Originates in one area of lymph system but can spread to entire lymphatic system and any tissue/organ if left untreated 

-Treatment = 98% survival rate 

hodgkin lymphoma

what is being described?

-absence of reed-sternberg cell

cause : unknown

• manfestations

  • Lymphadenopathy (enlarged, painless lymph nodes)- widespread 

  • Unintentional weight loss 

  • Night sweats & fever 

  • Increased risk for infection 

  • Can be multiple lymph nodes  

• survival rate- 75%

non-hodgkin lymphoma

Leukimas

• Malignant neoplasms originating from hematopoietic cells that cause an overcrowding of bone marrow with unregulated, proliferating, immature neoplastic cells that invade the blood stream. 

• In other words,... 

  • A bunch of abnormal cells that 

    • Do not function correctly 

    • Don’t die when they should, so they’re living longer  

    • Keep growing and growing 

    • Crowd normal cells and impede their functioning 

• Most common cancer in children / adolescents 

• Adults diagnosed 10 x more frequently than children 

• Cause is unknown  

• Classification of Leukemia 

  • There are four main classifications of leukemias: 

    • Acute lymphocytic leukemia (ALL) 

    • Acute myelocytic leukemia (AML) 

    • Chronic lymphocytic leukemia (CLL) 

    • Chronic myelocytic leukemia (CML) 

• Classification of Leukemia 

  • There are four main classifications of leukemias:

• Acute lymphocytic leukemia (ALL) 

• Acute myelocytic leukemia (AML) 

• Chronic lymphocytic leukemia (CLL) 

• Chronic myelocytic leukemia (CML) 

Leukimias have a first, middle, and last name:

Acute or Chronic, Lymphocytic or Myelocytic, Leukemia 

How are leukimas classified

by the onset/duration of malignancy and the cell type

Leukima Onset/duration

• Acute or Chronic 

  • Acute: Became malignant earlier on in the differentiation process 

  • Chronic: Became malignant a little bit later, it is a little more differentiated 

leukemia cell type

• Lymphocytic

  • lymphoid stem cell 

• Myelocytic 

  • myeloid stem cell  

Acute leukemias

1. Excessive number of undifferentiated, immature blast cells 

2. These immature cells do not function correctly 

3. Rapid rate of growth 

4. Sudden onset 

• Became malignant earlier on in the differentiation process 

Chronic Leukemias 

1. Excessive number of mature WBCs 

2. Mature WBCs are abnormal and do not function correctly 

3. Slower rate of growth 

4. Symptoms take longer to appear (usually mild at first) 

5. More common in adults and better prognosis 

• Became malignant a little bit later, it is a little more differentiated 

What…..

• Involves lymphoid cells 

• Two types: ALL and CLL 

Lymphocytic Leukemias 

What…

• Involves myeloid cells 

• Two types: AML and CML 

 

Myelocytic Leukemias 

Manifestations of all types of Leukemias: 

1. Increased risk of infection  

2. Malaise  

3. Anemia  

4. Abdominal pain  

5. Bone pain  

6. Fever  

7. Headache  

8. N/V  

9. Thrombocytopenia  

10. Bleeding 

What is multiple myeloma?

• Cancer of B cell plasma cells (immunoglobulins) 

  • B cells make antibodies  

• Categorized by which immunoglobulin is abnormal 

• Cause is unknown; associated with chromosomal abnormalities 

• Risk factors: 

  • Chronic immune stimulation 

  • Autoimmune disorders 

    • Environmental hazards: ionizing radiation, pesticides, herbicides 

• More common in adults > 60 years of age 

Pathogenesis of multiple myeloma

• Proliferation of malignant plasma cells in bone marrow and osteolytic bone lesions in the skeletal system 

• Proliferation of and activation of osteoclasts, leading to bone resorption and destruction 

Manefestations of multiple myeloma

• Pathologic fractures 

  • Bone break/fracture and we don’t know how it got there 

• Hypercalcemia 

  • As the bone is destroyed calcium is released into the bloodstream leading to hypercalcemia 

• Bone pain 

  • Usually first manifestation 

• Recurrent infections 

  • B cell lymphocytes are being affected so 

• Proteinuria 

• Anemia 

  • Bone marrow is being destroyed and bone marrow makes RBCs 

• Neutropenia (low neutrophils) 

• Thrombocytopenia (low platelets) 

• Possible presence of Bence Jones protein in the urine (destroys kidneys) 

• Mneumonic to remember this: 

  • OLD CRAB 

    • Old- old age 

      • C- calcium elevated (hypercalcemia) 

      • R- renal failure 

      • A- anemia 

      • B- bone lytic lesions  

Mneumonic to remember multiple myeloma manefestations

• OLD CRAB 

  • Old- old age 

    • C- calcium elevated (hypercalcemia) 

    • R- renal failure 

    • A- anemia 

    • B- bone lytic lesions  

A decrease in WBCs puts the person at risk for?

infection

An elevated RBC count due to chronic hypoxia with manifestations such as headache, dizziness, and poor concentration may be called?

polycthemia vera

A person with a solely plant-based diet would be most at risk for?

Iron deficiency anemia 

A virtual absence of neutrophils can be best described as?

Agranulocytosis 

Which of these is not considered a neoplastic disorder of WBCs?

Aplastic anemia  

A patient who has just received a blood transfusion and is experiencing fever, back pain, and hematuria is most likely experiencing?

A blood transfusion reaction 

A person with the blood type O negative can donate blood to ______ and receive blood from type(s) ______.

Pick one:

• Everyone 

• Only type O negative

Pick one:

• Everyone 

• Only type O negative  

Everyone, only type O-

What is one manifestation of multiple myeloma?

bone pain

A patient with thrombocytopenia is most at risk for?

bleeding

A manifestation of increased RBC destruction is?

jaundice

A manifestation of iron deficiency anemia is?

pica

Which patient most likely has pica?

A patient with an intense desire to eat soap

What hormone, secreted by the kidneys, stimulates RBC production in the bone marrow

Erythropoietin  

A patient has been having frequent nose bleeds. Which lab value indicated the most likely cause?

Platelets= 85,000 

A patient has multiple pathologic fractures and has a calcium level of 12.0. The WBC and platelet counts are low. These findings are more consistent with?

Multiple myeloma 

Which statement best describes petechiae?

Small, pinpoint hemorrhages

What is the underlying reason for the manifestations related to anemia?

Tissue hypoxia

A patient who has been on bedrest for 5 days after surgery develops a stationary blood clot in a deep vein in his right leg. What type of clot is this?

Thrombus 

How are leukemias classified(select all that apply)

onset or duration of the malignancy, cell type