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USMLE Step 1 Random Facts > Heme/Onc > Flashcards

Flashcards in Heme/Onc Deck (75):
1

typical features of multiple myeloma (think CRAB)

hyperCalcemia (from osteoclast release by osteoclast activating factor IL-1, IL-6)
Renal insufficiency (Ig light chains in urine - Bence Jones protein)
Anemia, primary Amyloidosis (beta2-microglobulin)
Bone lytic lesions (punched-out) + Back pain

also, M-spike
increased suscept to infections
Rouleaux formation (RBCs stacked like poker chips)

2

eosinophils contain

histaminase
arylsulfatase

limits rxn following mast cell degran

3

basophils contain

heparin
histamine
leukotrienes (LTD4)

4

mast cells can bind what?

bind Fc portion of IgE onto membrane --> when IgE cross-links upon antigen binding --> degranulation

5

fibrin mesh formed by what bonds

covalent

6

proteins C + S inactivate what factors

Va
VIIIa

7

warfarin inhibits what enzyme

epoxide reductase

8

antithrombin inhibits activated forms of factors:

II
VII
IX
X
XI
XII

9

vit K deficiency increases what lab values

PT and PTT!!

10

factor w/ shortest 1/2 life

VII

11

what are located inside endoth cells

tPA
thromboplastin (tissue factor)
vWF
PGI2

12

acanthocytes (spur cell) seen w/

liver disease
abetalipoproteinemia

IRREG spikes

13

basophilic stipping is what? seen w/?

aggregates of rRNA

Thalessemias
Anemia of chronic dz
Lead Poisoning
Alcoholism

"ACTors are based in LA"

14

bite cells seen w/

G6PD def

15

elliptocyte (aka pencil cell) seen w/

hereditary elliptocytosis

16

macro-ovalocytes seen w/

megaloblastic anemia
marrow failure

17

Ringed sideroblasts

**iron granules surround/encircle nucleus

sideroblastic anemia
lead poisoning
drugs, genetic conditions, myelodysplastic synd

18

schistocyte seen w/

DIC
TTP/HUS
traumatic hemolysis (metal heart valve prosthesis)
micro/macroangiopathic anemia

19

echinocyte (burr cell) seen w/

uremia
renal failure
pyruvate kinase deficiency
microangiopathic hemolytic anemia
mechanical trauma (prosthetic valves)

REG spikes

20

spherocytes seen w/

hereditary spherocytosis
autoimmune hemolysis (warm agglut type)

21

teardrop cells seen w/

myelofibrosis
bone marrow infiltration

22

target cells seen w/

HbC disease
Asplenia
Liver disease
Thalessemia

23

Heinz bodies are what? seen in?

oxidation of Hb sulfhydryl groups --> denatured Hb precipitation + damage RBC membrane --> form bite cells (when it goes thru spleen)

seen in G6PD def

24

Howell-Jolly bodies are what? seen in?

basophilic nuclear remnants in RBCs

seen w/ asplenia or w/ mothball digestion (naphthalene)

25

disting b/w Howell-Jolly bodies vs. Heinz bodies?

only ONE HJ body per cell; MANY Heinz bodies per cell

26

cause of alpha thal

deletions in alpha-globin genes
4 alpha alleles on chrom 16

27

cause of beta thal

point mutations in splice sites + promoter seq
2 beta genes on chrom 11

28

primary Hb seen w/ Beta-thal minor

HbA2 (alpha 2, delta 2)

29

primary Hb seen w/ Beta-thal major

HbF

30

lead inhibits what enzymes

ALA-D (buildup of ALA)
ferrochelatase (buildup of protoporphyrin)

31

lead poisoning sympt

Lead lines on gingivae or metaphyses of long bones
Encephalopathy and Erythrocyte Basophilic stippling
Abd pain and sideroblastic Anemia
Drops - wrist/foot drop

32

sideroblastic anemia etiology + tx

X-linked defect in ALA-S gene
acquired: alcohol, lead, INH (causes B6 def)
tx = B6

33

what does hepcidin do in anemia of chronic dz

limits Fe transfer from macrophages to erythroid precursors by binding ferroportin on intestinal mucosal cells (inhib Fe transport) + suppresses EPO prod

34

folate vs B12 def (non-symptoms)

folate:
-green vegetables/fruit
-absorbed in JEJUNUM
-normal methylmalonic acid levels

B12:
-animal products! (strict vegans often affected)
-absorbed in ILEUM
-increased methylmalonic acid levels

35

tx for orotic aciduria

uridine monophosphate

36

nonmegaloblastic macrocytic anemia causes =

liver dz
alcoholism
reticulocytosis
drugs (5-FU, AZT, hydroxyurea)

37

signs of intravascular hemolysis

decreased haptoglobin
increased LDH
Hb in urine
hemoglobinemia
hemosiderinemia

38

signs of extravascular hemolysis

increased LDH
increased unconj bilirubin --> jaundice!
splenomegaly
increased risk of gallstones

39

causes of aplastic anemia

radiation
drugs (benzene, chloramphenicol, alkylating agents, antimetabolites)
virus (parvovirus B19, EBV, HCV, HIV) - esp in sickle cell pts
Fanconi's anemia (DNA repair defect)
Idiopathic (primary stem cell defect - ex. telomerase def)
autoimmune

40

ass w/ pure red cell aplasia

thymomas
parvovirus B19
lymphocytic leukemias

41

PNH lab findings/tx?

CD55/59 negative on RBCs!!
tx = eculizumab

42

PNH triad?

hemolytic anemia
pancytopenia
venous thrombosis

43

"crew cut" on skull x-ray due to marrow hyperplasia seen in:

sickle cell anemia
beta-thal major

44

complic in sickle cell anemia

-aplastic crisis (parvo B19)
-**autosplenectomy (shrunken fibrotic spleen due to multiple infarcts) - increased suscept to encapsulated organisms; Howell-Jolly bodies seen
-splenic sequestration crisis - wedge-shaped infarcts + decreased H&H
-Salmonella osteomyelitis
-painful crises (dactylitis, acute chest synd, avascular necrosis usually of femoral head)
-renal papillary necrosis (due to low O2 in papilla) + microhematuria

45

what can cause both warm or cold type AIHA?

EBV, CLL

46

causes of warm agglutinin AIHA

SLE
CLL
alpha-methyldopa
infections/viruses

47

causes of cold agglutinin AIHA

CLL
Mycoplasma pneumo
infectious mononucleosis

48

microangiopathic anemia ass w/

DIC
TTP-HUS
SLE
malig HTN

49

macroangiopathic anemia ass w/

prosthetic valves
aortic stenosis

50

infections that destroy RBCs

malaria
Babesia

51

transferrin levels are a PRIMARY increase in what conditions

preg + OCP use

52

acute intermittent porphyria sympt + tx

5P's:
Painful abd
Port-wine colored urine
Polyneuropathy (peripheral)
Psych disturbances
Precip by drugs

tx = glucose + heme (inhibs ALA-S)

53

acute intermittent porphyria enzyme affected + substrate accum =

enzyme = porphobilinogen deaminase (aka uroporphyrinogen-1-synthase)

accum =
-porphobilinogen
-ALA
-uroporphyrin (in urine)

54

porphyria cutanea tarda enzyme affected + substrate accum =

enzyme = uroporphyrinogen decarboxylase

accum = uroporphyrin (tea-colored urine!!!!!!)

55

porphyria cutanea tarda sympt + ass w/?

***blistering cutaneous photosensitivity! (from ROS damage)
hypertrichosis (excessive hair growth)
facial pigmentation

ass w/ HCV, alcoholism, increased LFTs

56

ALA-S needs what cofactor

B6

57

Bernard-Soulier synd

decreased GpIb --> decreased platelet-vWF adhesion
see: mild TCP w/ ENLARGED platelets

58

Glanzmann's thrombasthenia

decreased GpIIb/IIIa --> defect in platelet-platelet aggreg
Lab = NO platelet clumping

59

ITP

anti-GpIIb/IIIa Ab (IgG)
increased megakaryocytes
usually wks after viral infection or immunization

60

TTP

deficiency of ADAMTS13 (vWF metalloprotease) --> large vWF multimers (the NON-active form) --> increased platelet aggreg --> thrombosis
labs: schistocytes!, increased LDH

61

sympt of TTP

pentad:
Neuro sympt
Fever
TCP
Hemolytic anemia
Kidney damage

"Nasty Fever Torched His Kidneys"

62

blood transfusion risks =

infection transmission (low)
transfusion rxns
Fe overload
hypocalcemia (due to citrate = Ca + Mg chelator)
hyperkalemia (RBC lysis in old blood units)

63

cryoprecipitate contains

fibrinogen
factor VIII
factor XIII
vWF
fibronectin

64

Reed-Sternberg cells = + for what markers

CD30+
CD15+
both B-cell origin

65

marginal zone lymphoma ass w/?

chronic inflamm conditions like:
Hashimoto's thyroiditis
Sjogren's dz
H.pylori gastritis

66

Waldenstrom's macroglobulinemia

IgM M-spike
NO lytic bone lesions
visual/neuro deficits + bleeding

67

Hairy cell leukemia unique features/tx

absent LAD!!
dry tap w/ bone marrow aspiration
TRAP +

tx = cladribine (adenosine deaminase inhibitor) or adenosine analog

68

common presentation of M3 AML

DIC

69

characteristic increase in what cell in CML

basophils

70

RF for CML =

ionizing radiation
benzene

71

Langerhans cell histiocytosis features?

lytic bone lesions + skin rash in child
do not efficiently stim T-lymphocytes via APC
cells express S-100 (neural crest origin) + CD1a
Birbeck granules!!

72

HIT caused by:

Ab-heparin-PF4 complex --> activate platelets --> thrombosis, TCP

73

cilostazol, dipyridamole MOA

PDE3 inhib --> increases cAMP in platelets --> inhib aggreg

also, arterial vasodilators

74

tx for CLL

fludrabine

75

prevent cardiotox induced by doxorubicin

dexrazoxane (iron chelating agent)