Anemia Flashcards
what is a better way to assess for folate deficiency rather than just serum folate level?
red cell folate
folate deficiency levels and what it means
< 2 = deficiency
2-4 = equivocal and should get MMA and homocysteine levels; normal MMA and high homocysteine = folate deficiency
B12 deficiency levels
< 200= deficiency
200-300 = equivocal. Should test MMA and homocysteine; if they are both elevated it is B12 def.
formula for iron deficiency replacement
calculated iron deficiency (mg)= body weight x (14-Hb) * 2.145
labs for ACD
low iron
ferritin is high or normal
TIBC is LOW because of increased hepcidin production in the liver and iron is trapped in macrophages
absolute retic count is often low
treatment for ACD
- can use EPO which decreases hepcidin and immediately releases iron from the stores; can give supplemental iron to achieve transferrin saturation > 20% and ferritin > 100 ng/mL
Red Cell aplasia risk factors
- thymoma> remember to get CT chest
- DFA
- Old EPO preparations which cause anti-erythrocyte Ab
- drugs including phenytoin, isoniazid, valproic acid, chlorambucil, AZA and mycophenolate
- T cell and B cell disorders
- parvovirus, mumps, hepatitis, EBV and HIV
red cell aplasia- labs
WBC and platelets are normal!
Abs retic < 0.1
normocytic normochromic anemia
pure red cell aplasia: treatment
- steroids
- steroids + cyclosporine or cyclophosphamide
- IVIG, plasmapharesis, AZA, rituximab, alemtuzumab (anti CD52), daclizumab (CD25, IL2 receptor T cells)
what is sideroblastic anemia? list some causes
dx due to inherited or acquired abnormalities in heme synthesis and mitochondrial function. ringed sideroblasts are erythroblasts with iron loaded macrophages
causes include:
- etoh
-INH, chloramphenicol, linezolid, cycloserine
- copper def which leads to zinc toxicity
- lead poisoning
- MDS with ringed sideroblasts
- X linked disorders making men more susceptible
sideroblastic anemia: treatment
- congenital: treat anemia with occasional transfusions but be mindful to avoid iron overload
- acquired: remove offending drug such as INH; can give B6 also and continue INH; treat underlying disorder
what is congenital Dyserythropoietic Anemia and what are the three types?
- CDA 1: caused by mutations in CDAN1 gene which encodes codanin-1 a cell cycle protein involved in histone assembly. It is Ar and often associated with cosanguinity. Can have moderate to severe macrocytic anemia; hepatomegaly and cholelithiasis are common. can have dysmorphic skeletal features. Iron overload is major cause of morbidity
- CDA2: more varied anemia from ild to severe; gaucher like cells and ringed sideroblasts are common. more than 10% of mature bi and multinucleated red cell precurors is a hallmark. AR pattern; mutations in SEC23B gene which encodes COPII involved in cis-golgi apparatus. Type 2 CDA is known as HEMPAS (hereditary erythroblastic multinuclearity associated with positive acid serum test)
- CDA 3: more mild anemia, usually asymptomatic. BM shows large multinucleate erythroblasts. AD with inheritaned mutations in KIF23 which is a gene than is critical for cytokines
CDA treatment
- iron chelation may be needed if ferritin > 500
- interferon is effective in type 2
- transplant
- type 3 is mild and doesnt need tx usually
Pathophysiology of WAIA
- almost always IgG Ab and bind to RBC at 37 degrees
- about 50% of IgG bind to Rh complex constituents
- Fc reeptors, complement C3 receptors, or both on reticuloendothelial cells bind these RBC and trap them in the spleen where macrophages opsonize them which leads to partial loss of the membrane and microspherocytes (small round red cell)
what are causes of WAHA?
- lymphoproliferative disorders like CLL, HL, NHL
- autoimmune dx like SLE
- drugs like cephalosporins, quinine
- other cancers such as ovarian
