7 Heme Onc Flashcards
B12 deficiency:
think what 4 causes for the test
- pernicious anemia–no IF
- crohn’s–attacks TI (absorption)
- pancreatic insuff (need proteases to release from salivary R-binder)
- Fish tapeworm
B12 vs Folate equivocal, get what?
Get MMA. If elevated, then B12 deficiency
Schilling’s test for B12
- give IM nonradioactive B12, saturate liver binding sites.
- give oral radioactive B12, then check if radioactive excreted in urine. If radioactive is present in urine, then it can be absorbed in gut.
- If not, then add other things to aid absorption: IF, abx if bacterial overgrowth, and pancreatic enzymes
Fe deficiency anemia.
-what is normal Fe daily requirement and max?
- how long to replace serum Fe, and how long to replace Fe stores?
- How much Fe in 1 PRBC unit?
1 mg/day, max 3 mg/day
serum Fe: 6 weeks
stores: 6 mo
350g Fe in 1 PRBC unit. So, 1 year’s supply.
anemia of chronic dz
-tx and decision making
Tx underlying dz. (eg SLE, RA). If can’t, can give EPO. helps body utilize Fe stores.
If Hgb>10, f/u labs in 3 mo
If <10, give EPO
Pt with microcytic anemia on blood test, but normal Fe studies. Think what. then do what/look for what
Thalassemia.
To dx, get Hgb electrophoresis. Can show B-Thal positive. But if neg, then A-thal is dx of exclusion
Also, LDH normal, but retic count low.
Thalassemia: how to think about it.
Classic vignettes
Pt either presents:
MILD: Asx–no tx.
-Asian person with isolated anemia and low retic count, LDH normal. Told couldn’t donate blood. (if Hgb electrophoresis negative, must be A-thal)
SEVERE: severe anemia–transfusion required, + deferoxamine
-16yoM comes with Hgb 3.2
Pt with microcytic anemia. Fe studies show elevated serum Fe.
do what
Sideroblastic anemia
Get pt away from lead, give B6, Confirm dx with bone marrow bx. (ringed sideroblasts)
Sideroblastic anemia:
causes to know (5)
Lead ETOH INH B6 def AML/myelodysplastic
Normocytic hemolytic anemias: (4)
name each, smear, confirm test, tx
- Spherocytosis
- smear +
- osmotic fragility test
- Folate and Fe if mild, splenectomy if severe - PNH
- smear -
- flow cytometry
- steroids, eculizumab - G6PD
- Smear: Heinz bodies and Bite cells
- G6PD levels 6-8 wks after attack
- avoid triggers - Autoimmune hemolytic anemia
- Smear: spherocytes
- Coombs test (IgG)
- steroids, IVIG, splenectomy
Blood smear: you see spherocytes. think what
Either spherocytosis, or AIHA.
Do Coombs. If positive AIHA. negative, spherocytosis.
PNH: what to remember
can have venous thrombosis in intra-abdominal veins, causing abd pain.
Sickle cell:
what test for avascular necrosis of hip/femur to know
DEXA scan screening
Leukemias, ages?
7, 47, 67, 87
ALL, CML, AML (must be older than CML for blast crisis), CLL
You suspect AML or ALL. What dx tests to do and not do
CBC not helpful, could be up or down
Blood smear, look for blasts.
Confirm with BM bx, >20% blsts