Manual Methods—Bench Questions Flashcards

1
Q

WBC dilution

A

1:20
3% acetic acid
1.9 mL + 100 uL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

procedure for WBC estimate

A

average WBCs in 1/4 field on 10x

manual count if >20% discrepancy from analyzer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

WBC correction for NRBCs

A

wbc(100)/(nrbc + 100) = corrected wbc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

how closely should sides on hemacytometer match?

A

<25 cells: ±5 cells
>25 cells: within 20%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

normal wbc ranges for adult and newborn

A
  • adult: 4.3-10.0
  • newborn: 5.0-30.0
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

causes of increased wbc

A
  • infection
  • leukemia
  • pregnancy
  • exercise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

causes of decreased wbc

A

chemo
viral infection
myelodysplastic syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

plt dilution

A

1:100
ammonium oxalate

lyses rbcs, but not retics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

area to count for plts

A

<200: 1 large square
>200: 5 small squares

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

normal plt
critical plt

A
  • normal: 140-400
  • critical low: <30
  • critical high: >800
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

plt estimate procedure

A

average plts on 100x * 15 and 20 to give range value should fall in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

why isn’t MPV calculated from manual count?

A

no way to calculate; derived from plt histogram

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

increased MPV

A

younger plts being released; thrombocytopenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

causes of thrombocytopenia

A

ITP
HIT
DIC
TTP
ALL
aplasic anemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

causes of thrombocytosis

A

IDA
CML
essential thrombocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

normal retic adult and newborn

A
  • adult: 0.5-2.0%
  • newborn: 2.5-6.5%
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

main causes of elevated retic

A
  • hemolytic anemia
  • blood loss
  • thalassemia
  • response to therapy for anemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Miller Ocular calculation

A

cells counted out of 112/10 = %

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

corrected retic takes into account…

calculation

A

smaller pool of rbcs in pts with low hct

corrected retic = retics(hct/45)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

retic index takes into account…

calculation

A

premature release of retics during anemia

retic index = [retics(hct/45)]/maturation time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

shift/stress retic

A

retics released early when H&H are low to compensate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

principle of sickle solubility

A
  • saponin lyses rbcs
  • Na hydrosulfite reduces released Hgb
  • reduced Hgb S is insoluble in phosphate buffer, so suspension is cloudy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

—–% sickling Hgb must be present for positive sickledex

A

10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

sickling hemoglobins other than Hgb S

A
  • Bart
  • C Harlem
  • C Georgetown
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Hgb S mutation

A

Chromosome 11
glutamic acid replaced by valine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Hgb S disease & trait on electrophoresis

A
  • disease: mostly Hgb S, some F and A2
  • trait: 60% Hgb A, 40% Hgb S, small amount of F and A2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

possible causes for false negative sickledex (2)

A
  • pt too young, <10% Hgb S
  • total Hgb <8 g/dL
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

sickledex procedure if Hgb <8

A

add 40 uL, not 20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

seen on smear of sickle disease & trait

A
  • disease: sickles, targets, nrbcs, HJ bodies, pappenheimers, poly
  • trait: targets
30
Q

best sample for OF test

A

Na heparin

31
Q

why are OF samples incubated 24 hours?

A

detect subtle abnormalities in OF that would not show up immediately

32
Q

normal beginning and ending OF hemolysis values

A

begins at 0.45%
ends at 0.35%

33
Q

HS rbc defect

A

spectrin membrane defect

34
Q

why do thal pts have ↓ OF?

A

targets and hypos can take in more water before lysing

35
Q

procedure for making KB control slides

A
  • negative control: normal male blood
  • 1:20: 1 drop cord + 19 drops male blood
  • 1:10: 1 drop cord + 9 drops male blood

6 drops saline + 4 drops control blood; make 20 thin slides

36
Q

reasons for performing KB

A
  • determine necessary RhIg dose
  • check for thalassemia (moth-eaten HgbF distribution)
  • check for hereditary persistence of Hgb F
37
Q

methodology of monospot

A

latex particles or rbcs coated with Ag specific to heterophile Ab in dipstick

dipstick is immunochromatographic

38
Q

samples for monospot

A

serum preferred

EDTA plasma acceptable if tested within 24 hours

39
Q

is monospot specific for infectious mono?

A

yes

40
Q

seen on smear of EBV pt

A

atypical lymphs, often >20%

41
Q

sx of EBV and other infections that cause similar sx

A

fever, malaise, sore throat, lymphadenopathy

CMV
toxoplasma

42
Q

can cause false negative monospot

A

children <12yo and 10-20% of adults

43
Q

reflex for negative monospot

A

EBV serology

if negative, CMV serology

44
Q

normal CSF rbc and wbc for adult and newborn

A

WBC
adult: 0-10
baby: 0-30

RBC
0 for both

45
Q

tube order for CSF

A
  1. chemistry
  2. micro
  3. hematology
46
Q

distinguish bloody tap from hemorrhage

A
  • distribution of blood in tubes
  • macrophages with hemosiderin/rbcs
  • clot formation(tap)
  • xanthochromic
47
Q

causes of xanthochromia

A
  • rbc degradation
  • bilirubin
  • increased protein
  • melanoma pigment
48
Q

lining cells seen in CSF

A
  • ependymal
  • choroid plexus
49
Q

bacterial infection CSF effects on glucose, protein

A

↓ glucose
↑ protein

50
Q

corrective action for nrbcs found in CSF

A

WBC correction formula

51
Q

what do we do with CSF of ALL children?

A

look at cytospin smear regardless of WBC count, to check for blasts

52
Q

cause for a BF to be rejected for count

A

clot

53
Q

lining cells

A
  • mesothelials (serous)
  • synoviocytes (joint)
  • ependymal/choroid plexus (csf)
  • epithelials (amniotic)
54
Q

synovial fluid cannot be diluted with…

A

acetic acid (clot)

55
Q

components of semen analysis and normal values (8)

A
  • pH: 7-8
  • count: >20 mil/mL
  • motility: >50% motile
  • liquefaction: liquefied
  • viscosity: not viscous
  • volume: 1.5-5 mL
  • morphology: <30% abnormal
  • vitality: 3+ to 4+
56
Q

no sperm
procedure

A

azospermia

fructose test; check for bilateral aplasia of seminal vesicles or obstruction of ejaculatory ducts

57
Q

sites for BM collection

A
  • posterior iliac crest (adult)
  • tibia (child)
58
Q

BM aspirate used for…

A
  • cytogenetics
  • flow
  • molecular
  • cultures
59
Q

BM core biopsy used for…

A
  • architecture
  • cellularity
60
Q

handling for each type of BM test

A
  • aspirate smear (EDTA, bedside)
  • flow (Na hep)
  • genetics (Na hep)
  • PCR (EDTA)
  • culture (SPS, or Na cit for viral)
  • biopsy (sent to histology in jar of fixative)
61
Q

BM diff procedure

A
  • count every other field
  • count 200 cells (100/slide)
  • differentiate nrbcs
  • assess cellularity, megakaryocyte, presence of malignants, M:E ratio
62
Q

normal BM diffs show…

A

pyramid form of full range of maturation

ME: 2:1 to 4:1

normal cellularity: 100-pts age, ± 10%

5-10 megakaryocytes per 10x field

63
Q

2 conditions causing hypersegmented neutrophils

A
  • megaloblastic anemia
  • myelodysplastic syndrome
64
Q

signs of wbc dysplasia

A
  • hyper/hyposegmented
  • agranular
  • asynchrony
65
Q

signs of rbc dysplasia

A
  • multinucleated nrbcs
  • fetal traits
  • asynchrony
  • karyorrhexis
  • ringed sideroblasts
66
Q

signs of plt dysplasia

A
  • giant
  • micromegakaryocytes
  • agranular
67
Q

leukemoid rxn

A
  • left shift
  • increased wbc
  • toxic changes
68
Q

CLL on smear

A

lymphs
smudgs
high wbc

69
Q

myelodysplastic syndrome on smear/bm

A
  • dysplasia
  • PB cytopenia in 1+ lines
  • BM hypercellularity
70
Q

leukoerythroblastosis associated with…

A

myelophthisis (crowding out)

71
Q

toxic changes to neutrophils

A
  • dohle bodies
  • toxic gran
  • vacuolization