12. Hematology Flashcards
Spoon nails/koilonychia and pale conjunctiva?
Iron deficiency
What is the carrier protein for iron?
Transferrin
Transferrin and TIBC relationship?
They are the same!
Ferritin and TIBC relationship?
Inverse/opposite
What is the shared problem in all microcytic anemias?
No hemoglobin
What happens in anemia of chronic disease?
Body locks iron up in the macrophages in the bone marrow
How do we differentiate ACD from iron deficiency?
Ferritin is increased in ACD vs. decreased in iron deficiency
What are sideroblastic anemias?
Iron accumulates because of defect in the synthesis of protoporphyrin
What is the rate limiting enzyme in the formation of heme?
ALAS
What is the most common cause of sideroblastic anemia?
Alcohol - mitochondrial poison
What vitamin deficiency leads to sideroblastic anemia?
B6 (pyridoxine) - associate with Isoniazid
What enzyme does lead poisoning affect?
Ferrochelatase (also has a little bit of effect on ALAD but mostly ferrochelatase)
Genetic inheritance of thalassemias?
Autosomal recessive
Who do we see alpha thalassemia in?
Black and Asian
How do we diagnose beta thalassemia?
Hgb electrophoresis
4 gene deletion in alpha thalassemia?
Hydrops fetalis, formation of tetramer of gamma chains (Hb Barts)
What do you form in 3 gene deletion of alpha thalassemia?
Tetramer of alpha chains - HbH
Why is there an increased rate of choriocarcinomas in Asia?
Increased spontaneous abortions from increased rate of hydrops fetalis from alpha thalassemia; the spontaneous abortions are correlated with increased rate of choriocarcinomas
How does alpha thalassema with 2 deletions show up on Hgb electrophoresis?
It doesn’t since you need alpha chain for all the hemoglobins- they are all decreased so the percentages stay constant. You can only see alpha thalassemia on electrophoresis with 3 gene deletion when you start to form HbH.
What is the most common cause of iron deficiency in women under 50?
Menorrhagia
What is the most common cause of iron deficiency in men under 50?
Peptic ulcer disease
What is the most common cause of iron deficiency in adults over 50?
Colon cancer
What is the most common cause of iron deficiency in child under 4?
Meckel diverticulum - bleed
