Lecture 12: Leukocyte Disorders Part 1 Flashcards
What is a bone marrow biopsy/aspiration?
Drilling a hole into bone to obtain cellular contents of bone marrow.
What are CIs of bone marrow biopsy?
Severe bleeding disorders (DIC, hemophilia)
Thrombocytopenia is a relative CI.
(it actually says that thrombocytopenia is not a CI but if they are <20,000 platelets then may want to consider infusion before obtaining biopsy)
What can we test with a bone marrow biopsy?
Histology
Cytogenetic testing (testing for chromosome abnormality)
Flow-cytometry (analyzes cells for abnormalities)
What are the indications of a bone marrow biopsy?
Diagnosing, staging and therapeutic monitoring of bone marrow disorders
Unecplained elevation or decreased in any hematopoietic cell line
Lymphoma/solid tumors
Evaluation of iron metabolism and stores when routine iron testing is inadequate
FUO
Unexplained slenomegaly
Where do we NOT perform a bone marrow biopsy?
Areas with signs of infection, injury, or excess overlying adipose tissue (NO FATTY AREAS)
What is the preferred site for a BM biopsy/aspiration?
Posterior iliac crest
Alt is anterior iliac crest
What is the preferred site for a BM aspiration only?
Tibia (under general anesthesia, used for infants <1yo)
Sternum (2nd and 3rd ICS, older than 12yo + morbid obese)
What is the main cause of acute lymphoblastic leukemia (ALL)?
Chromosomal translocation
What is ALL?
Malignant disorder that originates in a single lymphocyte, resulting from an abnormal expression of genes.
It is the cell immediately after the common lymphoid progenitor.
What 4 things does ALL result in?
Rapid cell proliferation/self-renewal
Reduction in normal cell proliferation
Block in cell differentiation
Increased resistance in cell apoptosis.
Essentially, it stays as an immature lymphoblast, making more of itself. Since it stays immature, it does not enter apotosis easily.
How does ALL impair hematopoiesis?
Accumulation of the lymphoblasts within the bone marrow suppresses the normal hematopoiesis since there is limited room.
Once it builds up, the bone marrow releases the lymphoblasts elsewhere to other organs.
How likely is ALL due to genetics vs environment?
Genetics are only 5% of cases.
95% are due to environmental factors.
What are the environmental factors associated with ALL?
In utero radiation exposure.
Chemicals
High birth weight (increase insulin-like growth factor 1)
LACK OF EXPOSURE to infections in the first few weeks of life.
Who is ALL MC in ?
Children, usually DXd prior to 15yo.
What gender is ALL MC in?
Males by a little.
What is the MC symptom in ALL?
FUO (fever of unknown origin)
What 3 hematologic conditions are common in ALL?
Neutropenia
Anemia
Thrombocytopenia
What is the main cause of all the S/S in ALL?
The direct infiltration of marrow or other organs by leukemic cells.
When does most deaths due to ALL occur?
In adults.
What are significant S/S of ALL?
LAN (often all lymph nodes, not specific)
Bone pain (a deep pain at night that wakes them)
Early satiety (splenomegaly bc stomach is compressed)
Mediastinal mass
Painless testicular swelling/mass
What is leukostasis?
Hyperleukocytosis, aka WBCs > 100k
Leads to inadequate circulation.
How emergent is leukostasis?
Very!
Risk of ICH, that lasts even 1 week after reduction.
40% mortality in 2 days if not treated.
How would someone would ALL potentially describe their symptoms?
Deep aching pains at night
Getting full very easily
Dysphagia, persistent chest pain
General swelling of lymph nodes
What would an initial workup of ALL be?
CBC
CMP
Blood cultures
CXR
CT/MRI Brain (WITHOUT contrast)