Heme/Onc Flashcards
Initial eval for patient with polycythemia?
EPO! –if elevated then think possible chronic hypoxia or possible renal cell carcinoma
Pt with polycythemia, you check —- & it comes back low. what would you check to test for PV?
Polycythemia Vera = Low EPO, JAK2 mutation
Osteo—- met’s will show up on plain XR. Where as Osteo— met’s often do not and require radioisotope bone scans.
Osteolytic = XR & PET (MM, some breast cancer) Osteoblastic = radioisotope (pancreatic cancer & some breast cancers)
Patient with a B 12 deficiency has a mildly elevated indirect bilirubin. Why?
Ineffective erythropoiesis is a well-known phenomenon that occurs in patients with vitamin B12 deficiency. The mechanism that leads to this phenomenon involves defective DNA synthesis with megaloblastic transformation of bone marrow and intramedullary hemolysis. Although intense erythroid hyperplasia occurs, the erythroid cells do not mature normally and subsequently die in the bone marrow. Markers of hemolytic anemia (eg, elevated lactate dehydrogenase, low haptoglobin, indirect hyperbilirubinemia) may become evident, but reticulocyte response is typically absent in such patients.
When switching from heparin to warfarin 2/2 HIT in a pt with a PE when can you start warfarin?
The first management step is to immediately stop all heparin products (including low molecular-weight heparin such as enoxaparin) and obtain confirmatory laboratory testing (eg, serotonin release assay). Alternate agents such as direct thrombin inhibitors (eg, argatroban, bivalirudin) or fondaparinux (synthetic pentasaccharide) should be given due to the high risk of thrombosis in type 2 HIT.
These agents are not administered orally; therefore, the patient with a pulmonary embolism would need to be transitioned to an oral anticoagulant. Initial treatment with warfarin is contraindicated, as rapidly dropping protein C levels cause a prothrombotic state. Warfarin is usually started after the patient is treated with a non-heparin anticoagulant and recovers a platelet count to ≥150,000/mm3.
How long after started heparin may u see HIT?
Type 2 heparin-induced thrombocytopenia (HIT) is an immune-mediated disorder resulting in platelet aggregation and thrombosis. HIT should be suspected clinically when platelet counts fall ≥50% from baseline 5-14 days after starting heparin, in new-onset unexplained thrombocytopenia, or with thrombosis in patients recently treated with heparin.
What test is used to monitor patients u der going chemotherapy with cardiotoxic agents? When is cardiotoxic agents C/I?
Radionuclide ventriculography, also known as a MUGA (multigated acquisition) scan, is typically used to monitor patients receiving cardiotoxic chemotherapy as it is a highly accurate and reproducible test for quantitating left ventricular ejection fraction. A radionuclide ventriculogram is generally performed at baseline before chemotherapy is initiated, and before each subsequent dose of chemotherapy. The therapeutic regimen is dependent on the baseline cardiac function, with anthracycline chemotherapy contraindicated in patients with baseline ejection fractions less than 30%, and modified dosing required for patients with baseline ejection fractions of less than 50%. A decrease in the ejection fraction by ten or more percentage points may warrant discontinuation of therapy.
Direct vs indirect Coombs test
Direct: antibody test to determine if antibodies are bound to the RBC membrane, indicative of hemolytic anemia
Indirect: serum test to determine if there are antibodies to Rh factor in the mothers blood
Causes of macrocytic anemia
B12 deficiency, folate deficiency, liver disease, thyroid disease
When should you be concerned for iron deficiency anemia and kids?
Kids who are greater than one year who were exclusively fed breast milk or whole cows milk
MCV, serum iron, Serum ferritin, TIBC, RDW with Iron deficiency anemia
Low MCV, high RDW, low serum iron, low serum ferritin, increased TIBC
How long after replacing iron stores should you continue treatment
3 to 6 months
Bone marrow aspiration a patient with sideroblastic anemia will show…
Ring sideroblast
Causes of acquired Sideroblastic anemia
Ethanol, chloramphenicol, cycloserine, pyrazinamide, metal toxicity(lead,zinc, copper)
Treatment of inherited sideroblastic anemia?
Pyridoxine
What role does hepcidin play in anemia of chronic disease?
Hepcidin blocks iron absorption. When iron is low hepcidin is normally low to stimulate iron absorption. Since chronic inflammation raises hepcidin levels it creates an iron deficiency due to decreased absorption
HUS sx
Hemolytic anemia, thrombocytopenia, AKI
