Rx_2.25 (HemOnc) Flashcards Preview

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Flashcards in Rx_2.25 (HemOnc) Deck (20)
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1

Fatigue, anorexia, weight loss + enlarged lymph nodes + blood smear ==> dx?

  • chronic lymphocytic leukemia (CLL) vs. small lymphocytic lymphoma (SLL)
    • CLL = >4000cells/mm3 in bloodstream (more than SLL)
  • "smudge cell" = characteristics finding on peripheral smear
    • fragile lymphocytes (B cells) are flattened in theprocess of examining smear
      • CD5
      • CD19
      • CD20
      • CD23

2

Warm-reactive autoimmune hemolytic anemia presentation and tx

  • sx/labs
    • jaundice
    • anemia sx/lab findings
      • increased retic count
    • positive warm-agglutinin test
  • tx
    • corticosteroids ==> interfere w/immune destruction of erythrocytes
      • inhibit Fc receptor-mediated clearance of sensitized RBCs

3

Txs of autimmune hemolytic anemias

  • IVIg ==> adult autoimmune hemolytic anemia
  • cyclosporine ==> tx of refractory autoimmune hemolytic anemia in children
  • splenectomy ==> tx in children w/chronic or refractory autoimmune hemolytic anemia

4

Direct vs. Indirect Coombs test

  • direct
    • anti-IgM/IgG added to patients serum
    • RBCs agglutinate if IgG/IgM is attached to the surface
  • indirect
    • normal RBCs added to patient's serum
    • if pt. has antiRBC antibodies ==> attach to normal RBCs
    • add anti-IgM/IgG; RBCs agglutinate if anti-RBCs have attached

5

Positive Coombs test indicates ==> ?

[most likely] autoimmune hemolytic anemia

6

Tx of acute DVT/PE

  • LMWH
    • e.g. enoxaparin
    • MOA: subq admin, inhibition of factor Xa
    • does not require monitoring

7

In warfarin tx, monitor...

  • PT (prothrombin time) = measure of extrinsic coag pathway
    • not standardized between labs
  • INR = standardized between labs

8

In heparin tx, monitor...

  • PTT (partial thromboplastin time) = measure of intrinsic coagulation pathway

9

Unfractionated Heparin: MOA

  • activation of antithrombin III ==> decreased level of available thrombin
  • inhibition of factor Xa

10

Serious complications of heparin

  • bleeding
  • heparin-induced thrombocytopenia )HIT)
    • antibodies against heparin-platelet factor 4 complexes ==> clotting
    • ==> MI, stroke, DVT
    • platelets ==> < 50% of prev. level 
    • occurs w/in 5-14 days 

11

Heparin antidote

protamine sulfate

12

Characteristics of hemophilia

  • x-linked recessive hematologic disorders
  • A = factor VIII deficiency
  • B = factor IX deficiency

13

Translocations assoc. w/hematologic malignancies

  • Burkitt's lymphoma = t(8;14)
    • 8 = c-myc
    • 14 = IgG heavy chain locus
    • ==> overexpression of c-myc
  • CML = t(9;22)
    • BCR-ABL fusion ==> increased tyrosine kinase activity
  • Mantle Cell lymphoma = t(11;14)
    • 11 = cyclin D1 
  • Follicular lymphoma = t(14;18)
    • 18 = BCL2 ==> inhibits apoptosis
  • AML (acute pro-myelocytic leukemia) = t(15;17)
    • 17 = retinoic acid receptor

14

fatigue, weight loss + enlarged spleen + peripheral smear ==> dx?

  • hairy cell leukemia
    • B-cells have "hairy" appearance
  • rarely presents w/fevers and night sweats
  • 4x more prevalent in men vs. women
  • elevation of tartrate-resistant acid phosphatase @ B-lymphs in bone marrow = confirmation
    • "TRAP the HAIRY beast"

15

older pt w/central area of necrosis + ring enhancing lesion @ R hemisphere ==> dx?

  • Glioblastoma multiforme
  • "pseudopalisading necrosis" = central necrosis + hypercellular zone
  • most common primary intracrainal neoplasm
    • usually @ older patients
  • poor prognosis

16

Skin biospy ==> dx?

  • basal cell carcinoma
  • gross = raised, pearly borders surrounded by fine telangiectasias
  • biopsy: palisading nuclei + nests of tumor cells

17

Presentation of acanthosis nigricans

  • gross
    • thickened hyperpigmented zones
    • velvet-like texture
  • assoc. w/ benign or malignant conditions
    • DM
    • adenocarcinoma

18

Presentation of actinic keratosis

  • most common pre-cancerous dermatosis

  • can progress ==> squamous cell carcinoma
  • gross = tan-brown, rough lesion <1cm in diameter
  • histology = cytologic atypia + intracellular bridging

19

Presentation of squamous cell carcinoma

  • patient w/frequent sun exposure
  • usually: actinic keratosis ==> SCC
  • histologically
    • pink, extracell concentration on H&E
  • gross
    • sharply-defined red, scaling plaques

20

Presentation of lentigo

  • benign lesion of childhood
  • gross
    • 5-10mm oval, tan-brown patches that do not darken w/sunlight
  • histo
    • linear basal hyperpigmentation from melanocyte hyperplasia

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