microcytic + macrocytic + normocytic anemias Flashcards
causes of IDA
blood loss: menstruation, occult blood loss: colon cancer, peptic ulcer
poor iron intake
↑ iron demand: pregnancy (also see phsyiologic anemia of pregnancy: plasma volume increases faster than RBC mass)
> 50 yo + IDA
r/o colon cancer with colonoscopy
IDA
esophageal webs (swallowing difficulty)
atrophic glossitis
Plummer-Vinson syndrome
causes of glossitis
vit. B deficiency:
B9 - folate
B12
IDA
defect in α globin: can be defect or deficiency
Hb: 2 α globins
2 α alleles on chrom 16: 2 copies of chrom from mom + dad → total 4 α alleles
Africans, Asians
alpha thalassemia
disease severity in alpha thalassemia
1 abnormal α allele: no anemia
2 abnormal α alleles: α thal trait/minor (no anemia) - most common type
3 abnormal α alleles:
hemoglobin H (ß globin pair up, most Hb = ß4)
4 abnormal α alleles: Hemoglobin Bart’s (gamma pair, Hb = gamma4 = hydrops fetalis → death)
defect in ß globin: can be defect or deficiency
total 2 ß alleles
Mediterranean
beta thalassemia
disease severity in beta thalassemia
Minor: ↓ amount of ß globin: minimal anemia ↑ HbA2 ↑ HbF Major: absent ß globin ↑ HbF marrow hyperplasia "hair-on-end": making new Hb "chipmunk facies" severe anemia: need blood transfusion → 2° hemochromatosis
treatment for 2° hemochromatosis from blood transfusions
deferoxamine: iron-chelating drug
target cells
beta thalassemia
also: THAL Thalassemia Hemoglobin C disease Asplenia Liver disease
“hair-on-end” or “crew cut” appearance of skull
beta thalassemia major
sickle cell disease
defective heme synthesis can cause this type of anemia
sideroblastic anemia: ringed sideroblasts in bone marrow
causes of sideroblastic anemia
hereditary form: ALA synthase gene chronic alcohol use drugs: seizure drugs INH chloramphenicol
iron not making heme:
↑ serum iron
↑ ferritin
ringed sideroblasts in BM
sideroblastic anemia
treatment of sideroblastic anemia
B6 supplement
defective iron utilization + mobilization
inflammatory state (IL-6): liver produces hepcidin → inhibits ferroportin in macrophages → iron trapped in macrophages (can't transfer to RBC precursors in bone marrow) ↓ serum iron, ↓ TIBC, N/↑ ferritin RA chronic infection malignancy
anemia of chronic disease
begins as normocytic anemia → microcytic anemia
impaired DNA synthesis
↑ time for RBC precursor to mature
cytoplasm expands in process → macrocytic
hypersegmented neutrophils: nucleus has > 6 lobes
vitamin B9/B12 deficiency
megaloblastic anemia
differentiating causes of megaloblastic anemia + glossitis + ↑ homocysteine
folate: no neuro sx normal MMA B12: neuro sx: peripheral neuropathy, dementia ↑ MMA
cause of folate deficiency
malnutrition (alcoholics)
malabsorption
meds: MTX, trimethoprim
high folate requirement: hemolytic anemia, pregnancy
causes of B12 deficiency
malnutrition (VEGANS, alcoholics)
malabsorption: pernicious anemia, chron disease, diphyllobothrium latum (fish tapeworm)
deficiency of UMP synthase for pyrimidine synthesis
orotic acid in urine
NO ↑ NH4
megaloblastic anemia
orotic aciduria
pancytopenia: anemia, leukopenia, thrombocytopenia
hypocellular BM + FATTY infiltration
aplastic anemia
anemia: fatigue, malaise, pallor
thrombocytopenia: purpura, petechiae, bleeding
leukopenia: infections
aplastic anemia
causes of aplastic anemia
radiation (cancer pt)
benzene
drugs: chloramphenicol, cancer drugs (alkylating, anti-metabolites)
viral infection: parvovirus B19, EBV, HIV esp in SICKLE CELL PATIENT (sensitive to these viruses)
Fanconi anemia: inherited defect of DNA repair
idiopathic - following acute hepatitis
no epo made
renal failure
diagnosis of beta thalassemia minor
hemoglobin electrophoresis: look for high HbA2
