Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
37 Cards in this Set
- Front
- Back
Why does normal hemoglobin level increase in boys with increased tanner stage?
|
Secondary to androgen effect on erythropoiesis
|
|
Where is iron absorbed?
|
primarily in the duodenum
|
|
What carries iron after absorption? In what form?
|
Transferrin binds Ferric (Fe3+)
|
|
When does iron depletion occur in an infant (term and pre-mature/low birthweight) who is not receiving iron supplementation (breast milk or formula)
|
term: by 5-6 months
pre-term/LBW: by 3 months |
|
what are the three stages of iron deficiency?
|
Depletion of iron stores
Iron Deficient Erthyropoiesis Iron Deficiency Anemia |
|
What is the first abnormality in iron deficiency?
|
decreased serum ferritin
|
|
What are two causes of malabsorption of iron?
|
celiac disease
giardiasis |
|
Does lead poisoning cause microcytic anemia?
|
Not usually, usually iron deficiency is underlying and leads to pica - the eating of lead
|
|
What morphologic finding is associated with lead poisoning?
|
basophilic stippling of erythrocytes
|
|
neurologic abnormalities are seen in folate or B12 deficiency?
|
B12 deficiency
|
|
What morphological finding is associated with folate or b12 (cobalamin) deficiency?
|
hypersegmented neutrophils
|
|
What lab findings are associated with folate or B12 deficiency?
|
can have mild thrombocytopenia and/or neutropenia
elevated bilirubin macrocytic anemia |
|
Where is folate absorbed?
|
proximal jejunum
|
|
What happens to homocysteine levels in folate deficiency? What effect does this have on thrombosis?
|
Plasma homocysteine levels are elevated which leads to an increased risk of thrombosis
|
|
What is required for the absorption of Vitamin b12 (cobalamin)? Where does absorption take place?
|
instrinsic factor
the instrinsic factor is produced by gastric parietal cells and the IF-b12 complex is absorbed in the terminal ileum |
|
What diet type can lead to Vitamin b12 deficiency?
|
vegan (no meat or dairy)
|
|
What is Imerslund-Graesbeck syndrome?
|
Malabsorption of Vitamin 12 - not corrected by IF
problem is an ileal receptor defect presents in early infancy includes RENAL DISEASE |
|
What is the treatment for Imerslund-Graesbeck syndrome?
|
IM Cobalamin
|
|
What are the manifestations of Transcobalamin-II deficiency?
|
Failure to Thrive
Pancytopenia Diarrhea Presents in early infancy |
|
What are the lab findings in Transcobalmin-II deficiency?
|
normal folate and Vitamin b12
low or absent TC-II levels in the serum |
|
What is pernicous anemia due to?
|
decreased intrinsic factor
|
|
How do you detect pernicious anemia?
|
Schilling Test, corrected by addition of instrinsic factor
|
|
Is adult or juvenile pernicious anemia associated with autoimmune disorders?
|
adult
|
|
What are three disorders that can cause cobalamin deficiency in the face of normal intrinsic factor?
|
ileal resection
inflammatory bowel disease Imerslund-Grasbeck Syndrome |
|
what happens if you treat vitamin b12 deficiency with high dose folate
|
you mask the vitamin b12 deficiency and do not address the neurologic problems which will persist
|
|
Why does copper deficiency cause microcytic anemia?
|
Copper is necessary for iron transport
|
|
Signs of copper deficiency
|
microcytic anemia, neutropenia and ricketts like bone disease
|
|
what causes anemia of inflammation (aka anemia of chronic disease)
|
shortened RBC survival combined with decreased RBC production
can follow mild and severe illnesses |
|
What cytokine in particular can inhibit erythropoeisis
|
IL-6
this fact contributes to anemia of inflammation |
|
What cytokine stimulates hepcidin by hepatocytes
|
IL-6
|
|
How does increase in hepcidin contribute to anemia of inflammation?
|
reduces intestinal absorption and macrophage release of iron
therefore reduced serum iron (more iron are in macrophages) |
|
What state is iron in in methemoglobinemia?
|
oxidized (Fe3+) rather than reduced (Fe2+)
|
|
When is methylene blue an ineffective antidote for methemoglobinemia
|
G6PD deficiency
Hgb M |
|
why are infants at increased risk of methemoglobinemia
|
relative deficiency of cytochrome B5 reductase
|
|
At what age do exclusively breast fed babies require iron supplementation?
|
6 months
|
|
what form of iron is best absorbed in the duodenum?
|
heme iron (as found in meat)
|
|
What are two inherited means of acquiring methemoglobinemia
|
cytochrome B5 reductase deficiency (autosomal recessive)
hemoglobin M resulting in FE3+ (dominant inheritance) |