244/245 - Intro to CBC, Approach to Anemias, Anemia CBL Flashcards
RBC characteristic associated with autoimmune hemolysis
Spherocyte (Dark RBC with no central pallor)
What is the next diagnostic step when RBC agglutination is found on a blood smear?
Warm up the sample, look again
(And probably run labs again to get accurate values for RBC count, MCV)
What could result in a falsely high RBC count? (2)
Marked leukocytosis (WBCs contribute more than expected)
Giant platelets (Platelets counted as RBCs)
Describe the RBC morphology in iron deficiency anemia
Microcytic, hypochromic anemia
What shape will RBCs be if there is excess RBC membrane relative to the its volume?
Target cells
- Macro target cells: liver disease*
- Micro target cells: Hemoglobinopathy (thalassemia, HbgE, HgbC)*
What is the finding indicated by the arrows?
What is the DDx? (3)
Spherocytes
- Hereditary spherocytosis
- Autoimmune hemolytic anemia
- Burns
RBC characteristic associated with hereditary elliptocytosis
Ovalocyte
Also associated with B12/folate deficiency, iron deficiency
Are symptoms of orthostatic hypotension, headache, and tachycardia more likely with acute or chronic anemia?
Acute
No time for compensatory mechanisms to develop -> more symptoms
A patient with sickle cell disease has this finding
What does it indicate?
Splenic failure
List 4 clinical scenarios in which you would see increased numbers of immature RBCs on a peripheral blood smear
- Newborns (<5 days old)
- Brisk hemolysis
- Myelodysplasia
- Extramedullary hematopoiesis
Intravascular hemolysis will cause red blood cells to be what shape?
Schistocytes
What could result in a falsely low RBC count? (2)
RBC agglutination (Multiple RBCs counted as one)
Microcytosis (RBCs too small to be counted)
What does mean corpuscular hemoglobin (MCH) measure?
The amount of hemoglobin in each RBC
Vs MCHC, which measures hemoglobin concentration in a given volume of packed RBCs
What does mean corpuscular Hb concentration (MCHC) measure?
Hemoglobin concentration in a given volume of packed RBCs
Vs. MCH, which measures amt of hemoglobin per RBC
List 3 CBC abnormalities present in sickle cell anemia
Reticulocytes high
Leukocytosis
RBCs will be normocytic, normochromic
What could cause a falsely low platelet count? (3)
Clotted sample
Platelet clumping
Frequent giant platelets
What does MCV measure?
Average red blood cell size (volume)
List 6 clinical scenarios that would cause RBCs to turn into “spur cells” (acanthocytes)
Liver disease
Abetalipoproteinemia
Vitamin E deficiency
Hypothyroidism
Post-splenectomy
Anorexia/Nutritional deficiency
What is the finding indicated by the arrows?
What is the DDx? (2)
Schistocytes
- Mechanical shear
- Hemolysis (MAHA)
- DIC
- HUS
- TTP
- HELLP
What could cause falsely high hemoglobin? (4)
Anything that increases turbidity of the sample
Hyperlipidemia
Hyperbilirubinemia
High protein
Marked leukocytosis
Hemoglobin measured spectrophotometrically; anything that makes the sample cloudier = less light = interpreted as more hemoglobin
What does hematocrit (HCT) measure?
Volume of RBCs / blood volume
(Basically, the percentage of blood made up by the actual cells)
How will the hemoglobin/oxygen dissociation curve change as a result of anemia?
Right shift
- Via increased 2,3 bisphosphoglycerate
- Allows existing RBCs to offload more oxygen to tissues to try to meet oxygen demands
2,3 BPG is the same thing as 2,3 DPG bc why not ¯_(ツ)_/¯
RBC characteristic associated with myelofibrosis
Teardrop cell
What defines anemia?
Decreased number of circulating red blood cells
RBC characteristic associated with microangiopathic hemolytic anemia
Schistocytes
What is the morphology finding indicated by the arrows?
What is the DDx? (4)
Hypochromic, microcytic, increased RDW
- Iron deficiency anemia
- Thalassemia
- Lead poisoning
- Anemia of chronic disease
What is the MOA of RBC agglutionation?
IgM antibodies against RBCs
- One IgM antibody can bind 5 RBCs -> Clumping
RBC characteristic associated with G6PD deficiency
Bite cell
(G6PD causes Heinz body hemolysis, results in bite cells)
List 4 compensatory mechanisms for anemia
- Increased cardiac output
- Tachycardia
- Altered blood flow
- Maintain O2 delivery to most important organs
- Increased EPO
- Increased 2,3-Bisphosphoglycerate
- Causes RBC to have less affinity for O2
- -> Right shift, allows more O2 offloading to tissues per RBC
When is splenectomy indicated in sickle cell disease?
1 or more episodes of hyper-splenism
How do bite cells form?
- Heinz bodies form in cells suceptible to oxidative damage
- When the RBCs try to filter through the basement membrane, Heinz bodies get stuck
- The rest of the cell moves on, leaving a “bite” where the Heinz body got left behind
What does red cell distribution width (RDW) measure?
Degree of variation of RBC
Lots of variation = high RDW
RBC characteristic associated with iron deficiency anemia
Hypochromic, microcytic
May see ovalocytes
Also associated with thalassemia
What could cause falsely high MCV? (3)
RBC agglutination
Osmotic abnormalities (Hyperglycemia, hypernatremia)
More young RBCs
List 3 components of the initial laboratory evaluation for anemia
CBC
Reticulocyte count
Peripheral blood smear
