Pediatric Anemia - Newman Flashcards
A reduction of Hb concentration or RBC volume below the range of values occurring in healthy persons
anemia
concentration of 2,3-DPG increases within the RBC
- oxygen dissociation curve shifts to the RIGHT
- affinity of Hb for O2 is reduced in tissues needing to oxygenated
physiologic response to anemia
- increases cardiac output
- enhanced oxygen extraction
- blood flow shunts to vital organs
what family hx should you ask about in peds anemia pt?
- anemia
- splenomegaly
- jaundice
- early-age onset of gallstones
what clinical features would you see once anemia becomes more severe?
- weakness
- tachypnea
- SOA
- cardiomyopathy
what lab tests do you order for anemia pt?
- Hb/Hct
- CBC: MCV, MCH, MCHC
what is MCV?
mean corpuscular volume
- mean value of volume of RBC’s in sample
what is MCHC?
mean corpuscular hemoglobin concentration
- Hb/Hct
what is MCH?
mean corpuscular hemoglobin
- average content (mass, weight) of Hb per RBC
what is RDW?
red cell distribution width
- measure of variability of RBC sizes in sample
- is a percent (if all RBC’s were exactly same size, would be 0%)
what is a peripheral smear?
provides information about RBC and WBC morphology, platelet clumping and hemolysis
anysocytosis
different SIZE
poikilocytosis
different SHAPES
schistocytosis
fragments of RBC’s
anemia with MCV <2.5 percentile for age,race, sex
microcytic
anemia with MCV between 2.5 and 97.5 percentile for age, race, sex
normocytic
anemia with MCV >97.5 percentile for age, race, sex
macrocytic
MCHC <32 g/dL
hypochromic
MCHC 33-34
normochromic
MCHC >35
hyperchromic
what causes decreased RBC production?
ineffective erythropoieses
what causes increased destruction of RBC’s?
- intravascular: mechanical injury, complement fixation, parasites, toxins
- extravascular: macrophages in reticuloendothelial system
low or low-normal number of reticulocytes in a pt with anemia is indicative of what?
inadequate bone marrow response KNOW this
increased number of reticulocytes is normal response to what?
anemia (bone marrow trying to keep up)
when do you see Howell-Jolly bodies?
in asplenic pt (post-spelenctomy)
when do you see the lowest point of Hb/Hct in healthy term infants?
- *2 months** KNOW this
- lowest point called the nadir
what is the age-specific cause of anemia in neonates?
immune hemolytic anemia
what lab values would see for autoimmune hemolytic anemia?
- positive direct Coombs test
- elevated indirect bilirubin
- normocytic anemia
- elevated reticulocyte count
what is the most likely cause of congenital infection causing anemia in neonates?
parvovirus B19
macrocytic anemia with low reticulocyte count
Diamond-Black syndrome
- aka congenital pure red cell aplasia, resulting from increased apoptosis in erythroid precursors
macrocytic anemia and reticulocytopenia, thrombocytopenia, leukopenia
- most common inherited form of aplastic anemia
Fanconi anemia
- progresses to pancytopenia
what is the most common cause of anemia in infancy to toddlerhood?
iron deficiency anemia
- pay attention to cows milk consumption (not enough iron)
what would peripheral smear show in iron deficiency anemia?
- hypochromic microcytes
- target cells
what is the mentzer index?
used to differentiate iron def anemia from beta thalassemia
- MCV/RBC count
what does a mentzer index >13 indicate?
iron deficiency anemia
what does a mentzer index <13 indicate?
beta thalassemia
what two deficiencies cause anemia?
- G6PD (Heinz and bite cells!)
- pyruvate kinase (spur cells)
toxicity of what would lead to microcytic, hypochromic anemia?
- peripheral smear may show basophilic stippling
lead poisoning
