Hematology/Oncology Flashcards
MCV?
Mean corpuscular volume:
- The average volume or size of a single RBC
MCH?
Mean Corpuscular Hemoglobin:
- Average amount of hemoglobin in RBC
MCHC?
Mean corpuscular hemoglobin concentration
- similar to MCH
RBW
Red Blood Cell distribution width
- Indication of the variation of RBC size.
- Indicator for anisocytosis
Peripheral Blood smear?
Involves spreading a drop of blood thinly onto a glass slide.
- Gives info on number, shape and general appearance of blood cells.
Causes of anemia?
Increased demand: rapid growth, prego, epo tx
Increased Fe loss: blood loss, menses, etc.
Decreased Fe absorption: diet, malabsorption (celiacs, crohn’s), surgery, inflammation
S/sx: of anemia?
Fatigue, tachycardia, palpations, dyspnea on exertion.
Severe: skin/mucosal changes (smooth tongue, brittle nails, koilonychia = spooning of nails, cheilosis
Iron deficiency anemia?
microcytic
Eti: most often due to blood loss, also decreased absorption
Dx: Hb and HCT low, serum ferritin levels less than 12, serum Fe low, TIBC (total iron binding capacity) high, reticulocyte count, MCV and MCHC low
B12 deficiency etiology
macrocytic
Pathophys: folate and B12 are required for DNA synthesis and effect normal cell growth and leads toward macrocyctosis
Eti: lack of intrinsic factor (IF enables body to absorb B12); altered pH in small intestine; diet, pernicious anemia (autoimmune against parietal cells or IF), bariatric surgery
B12 deficiency s/sx
Can lead to changes in the muscosal cells:
- glossitis, GI issues (anorexia, diarrhea)
Neuro: paresthesias that can lead to difficulties with balance and proprioception
Cognition: AMS, memory changes, other neuropsych sx.
Can cause jaundice, leukopenia, thrombocytopenia
Hypersegmentation of neutrophils on peripheral blood smear
B12 deficiency Dx and Tx:
- Low serum B12 and elevated MCV
- Hypersegmented neutrophils
- Reduced reticulocyte
- elevated lactate dehydrogenase
- modest increase in bilirubin
- increase in MMA and homocysteine
- differentiate from folic acid def
Tx: B12 IM or SubQ
Folate deficiency etiology
- Most common cause inadequate dietary
- ETOH, anorexic patients
- diet low in fruits and veggies
- Drugs: phenytoin (tx: seizures) , TMP-SMX, sulfasalazine (treats ulcerative colitis and RA)
- Folic acid requirements go up in pregnancy, hemolytic anemia, exfoliative skin disease
Folate deficiency S/sx:
Similar to B12 def, except no neurologic abnormalities
What is PT in hemotology?
Prothrombin time
Used to evaluate the extrinsic pathway and the common pathway of the coagulation cascade.
It can be reported in INR, international normalized ratio
What is aPTT?
Activated partial thromboplastin time.
Used to evaluate the intrinsic coagulation system and the common pathway.
Most often used to monitor heparin therapy.
Reference range for platelets
normal: 150,000 to 400,000.
spontaneous bleeding risk starts at less than 20,000
What are FSP
Fibrin split products:
Used to document a fibrin clot, shows thrombosis occurring in a patient
Direct coombs test?
Used to identify immune hemolysis or to investigate a transfusion reaction.
- Demonstrates if RBCs have been attack by antibodies in patients own blood
Indirect Coombs test?
Used to identify circulating AntiBs against RBCs.
Can detect minor serum antibodies other than major ABO/Rh system
INR?
standard way of reporting PT time.
D-dimer?
Used to assess thrombin an plasmin activity.
D-dimer is a fibrin degradation fragment that is made through lysis of cross-linked fibrin.
Think: DIC, PE, DVT, sickle cell, malignancy
Thrombocytopenia etiology?
DDx?
Eti: Decreased bone marrow production, sequestration, enlarged liver, increased platelet destruction.
DDX: Infection-induced thrombocytopenia, drug-induced T, Heparin-induced T, immune T, inherited T, thrombotic thrombocytopenic purpura
S/sx of thrombocytopenia?
Dx?
Petechia, possible spleenomegaly, bruising
Dx: CBC, bone marrow eval, anti-heparin/PF4, HIV, Hep C
Thrombocytosis. Eti?
Body produces too many platelets
Eti: Iron deficiency, inflammation, cancer, infection.
Can also be: essential thrombocythemia, or polycythemia vera
