Symptoms of Anemia
Weakness, fatigue, dyspnea
Pale conjunctiva and skin
headache and lightheadedness
Angina, especially with preexisting CAD
Definition of anemia
Hb <13.5 in males
Microcytic anemia (four general causes)
Iron absorption in the GUT
Absorbed in the duodenum (acidic environment favors Fe2+, better for absorption)
DMT1 brings it into enterocytes, ferroportin takes it into blood. Stored in liver and bone marrow macrophages.
Why is gastrectomy linked to Iron deficiency?
Decreased acid production –> more iron in Fe3+ state, poorer absorption.
Four Stages of Iron Deficiency anemia
Clinical findings with Iron deficient microcytic anemia
Anemia, koilonychia (spoon shaped nails), and PICA!
Lab findings of iron deficient anemia
Plummer Vinson syndrome
Iron Deficiency Anemia + Esophageal web (dysphagia) + Glossitis
Lab findings with Anemia of Chronic Inflammation
Increased ferritin, decreased TIBC, decreased serum Fe and %sat.
Protoporphyrin synthesis key steps (3)
In protoporphyrin deficient sideroblastic anemias, where is the iron located???
In MITOCHONDRIA surrounding the nucleus.
Most common cause of congenital sideroblastic anemia
Defects in ALAS (aminolevulinic acid synthetase)
Acquired causes of sideroblastic anemia (3)
Lab findings with Sideroblastic anemia
IRON OVERLOAD:
Increased ferritin, decreased TIBC, increased serum iron and %sat.
Evolutionary advantage of Thalassemia
Protection against P. falciparum
HbF
alpha2gamma2
HbA
alpha2beta2
HbA2
alpha2delta2
Cause of a-Thalassemia
gene deletion of one or more copies of alpha gene (4 total) on Chromosome 16
HbH
beta chain tetramers seen in a-Thalassemia (3 deletions)
Hb Barts
gamma chain tetramers formed in utero in fetuses with 4 gene deletion a-Thalassemia. This is lethal in utero (hydrops fetalis)
Cause of b-Thalassemia
Mutations resulting in absent or diminished b globin production on chromosome 11
Findings with b-Thalassemia minor on electrophoresis
Decreased HbA, increased HbA2, increased HbF