Lab and Dx Assignment Flashcards
(93 cards)
1
Q
ID the specific tests included in the Chem-strip 9-10* (dipstick) / usefulness
A
- leukocytes–ID infx–improved when combined w/ nitrite
- nitrite–support dx of infx–bac convert nitrate->nitrite
- urobilinogen–assist in ID of V liver
- bilirubin–assist in ID of v liver fx–Hgb breakv product
- protein–assist in ID of kidney dz–usually albumine
- pH–assist in ID of infx–no normal or abnormal pH
- blood–ID infx, stone, tumor
- ketones–assist in dx of DM–fasting–breakdown product of fat
- glucose–assists in ID of DM–usu. reabsorbed in PCT
* 10. (specific gravity)–ID dehydration–kidney’s ability to concentrate urine
2
Q
3 imp steps to minimize error when using Chem-strips
A
- follow time specifications
- store strips properly
- check expiration date
3
Q
where are monocytes primarily formed
A
spleen
4
Q
where are granulocyte primarly formed
A
bone marrow
5
Q
Which of the following tests, when positive, improves the sensitivity of the leukocyte esterase test in detecting a UTI:
nitrite, pH, protein, blood, SG
A
nitrite
6
Q
which factor improves the accuracy of the nitrite test
A
first void urine in the am bumps it to 90%
7
Q
what can interfere w/ the nitrite test
A
large amounts of ascorbic acid
8
Q
why is it important to test clean catch urine right-away
A
pH accuracy
9
Q
what can high pH (alkaline) indicate
A
dx of infection
10
Q
what is the predominant protein filtered by the kidneys in pt’s w/ proteinuria
A
albumin
11
Q
list (5) potential interfering factors in a urine sample w/ proteinuria
A
- extreme exercise
- ^emotional distress
- pregnancy
- immediate post-partum
- leaving dipstick in sample too long
12
Q
List (5) conditions when ketones when ketones may be present in urine
A
- DM!!!
- starving
- dieting
- anorexic
- febrile
13
Q
where is bilirubin formed
A
the spleen and bone marrow from Hgb breakdown and transport to the liver
14
Q
what causes bilirubin concentrations to drop rapidly
A
light exposure
15
Q
what acts on bilirubin (component of bile) converting it to urobilinogen
A
bacteria in the gut
16
Q
(5) conditions that can cause an increase in the urine concentration of urobilinogen
A
- Hep
- liver injury
- cirrhosis
- anemia
- malaria
17
Q
What time of day is urobilinogen highest in urine
A
btwn 12-4 PM
18
Q
food that can cause a + urobilinogen test
A
bananas
19
Q
What does specific gravity measure
A
the kidney’s ability to concentrate urine as compared to the weight of distilled H2O (1.000)
20
Q
(3) factors that determine urine’s SG
A
- pt’s hydration status
- urine volume
- load of solids to be excreted
21
Q
what affect will radiopaque contrast media have on the SG
A
False High SG
22
Q
What needs to be done to the urine sample prior to microscopy when performing urinalysis
A
“spun-down” w/ centerfuge
23
Q
what are the (3) main pathologic elements of interest when examining urine sediment
A
- WBCs
- Casts
- RBCs
24
Q
What is the implication of excess epithelial cells in the urine sample when performing a urinalysis
A
pt didn’t adhere to clean catch protocol
25
List (5) causes of hematuria that you should consider in your pt's w/ blood in the urine
1. stone
2. acute glomerulonephritis
3. tumor
4. BPH
5. UTI
26
presence of 6-10+ neutorphils/ HPF of urine
pyuria
27
* How can you distinguish pyuria caused by a lower UTI from that of pyelonephritis
presence or absence of proteinuria
28
what affect does urine sitting for >2-3 hrs have on WBCs? How can you avoid this problem?
1. WBC's lyse in alkalinized urine, so test urine sample in timely manner--sample will look normal if allowed to sit too long.
29
What substance is a necessary ingredient in cast formation
protein
30
These "molds" provide a glimpse of the condition of the nephron where they are formed
casts
31
where does cast formation usually occur
distal convoluted tuble and the collecting tubules of the nephron where the [urine] is greatest
32
which cast types are always of pathologic significance
1. Cellular
2. fatty
3. RBC
4. WBC
5. waxy
6. epithelial
7. granular
* always significant*
33
which cast type has little significance
hyaline casts--conglomeration of mucoproteins
34
What is the implication of the presence of WBCs and/or RBCs as part of cellular casts
renal origin--indicative of some disease process
35
if the cast is unrecognizable due to degradation, referred to as
granular cast
36
What is the most important factor in determining whether a cellular cast progresses to a waxy cast
time it takes the cast to move from the kidney to the urine
37
what is the significance of the appearance of waxy casts in the urine
indicates severe renal tubular stasis and nephron injury associated w/ severe chronic renal disease and renal amyloidosis
38
what are renal tubular epithelial casts associated w/ (3)
acute tubular necrosis, cytomegalovirus, toxin exposure
39
what are fatty casts and how do they form
fat globules, when there is renal tubular damage w/ susequent fatty degredation of the tubular epithelial cells
40
When one sees floating fat droplets in urine -- associated w/
oval fat bodies,
| nephrotic syndromes
41
(5) nephrotic disorders you'll see fatty casts and/or oval fat bodies
1. subacute glomerulonephritis
2. SLE (lupus)
3. amyloidosis
4. chronic GN
5. toxic poinsoning
42
Under what circumstances would you expect to see broad casts in the urine
wider than normal casts--when there is severe stasis in kidney--> casts form in more distal collecting tubules
43
How long does a urine culture take before results can be available
48 hrs
44
what is the most reliably uncontaminated urine sample method
suprapubic bladder tap using sterile field and teq
45
How are ABX "sensitivities" obtained during a urine culture
ABX discs -- zones of inhibition
46
Which pt type is a particularly ^ risk for transitional cell bladder cancer
CC often "Blood in my urine",
| Older pt who is a smoker at ^est risk
47
T/F A clean catch urine is not necessary when performing a urine cytology test
F -- sample may be gathered during cystoscopy
48
What is the purpose of FISH
tests the genetic material of the cells in the urine sample thus enabling better cancer detection
49
What is the next step in evaluating a pt w/ an abnormal FISH test
cystoscopy and Bx for histo confirmation
50
What medical term is used to describe an evaluated BUN? Describe the (3) main types of this disorder
-Azotemia- kidney fx/dysfx-
| AKI (1. pre-renal, 2. intrinsic, 3. post-renal)
51
List (4) causes of elevated BUN
1. excessive quantities of urea being present to kidneys
2. decreased renal blood flow which V GFR
3. intrinsic renal disease which V glom/tube fx
4. urinary obstruction causing urine backup
52
What BUN finding constitutes:
1. normal glomerular function
2. severe renal impairment (severe Azotemia)
1. 8-20 mg/dL
| 2. >50 mg/dL
53
T/F Serum Creatinine (Cr) is more sensitive a specific for renal dz than the serum BUN
T--breakdown product of creatine phosphate from muscular metabolism
54
What factor strongly determines a person's serum Cr level
body muscle mass--men higher reference range
55
List (5) reasons why a serum Cr could be elevated
1. renal failure (pre/ intrinsic/postrenal)
2. NSAIDS
3 .aminoglycocydes
4. gigantism
5. muscle necrosis
56
what must be taken into account when deciding what time of day to draw your pt's serum Cr level (2)
1. muscle mass
| 2. time of day (lowest 7am--highest 7pm)
57
Which of the 2 kidney fx markers, BUN or Cr, is a better indicator of chronicity of a pt's renal dz
Cr
58
Of what utility is the BUN:Cr ratio to you in working up your pt w/ renal dz
helpful in differentiating pre-&post renal azotemia from intrinsic azotemia
59
what affect would a 50% decrease in a pt's GFR have on their BUN or Cr levels
aprx doubling of their BUN or Cr levels
60
List (5) conditions which would DECREASE BUN:Cr ratio
1. malnutrition
2. low-protein diet
3. ketoacidosis
4. pt's receiving hemodialysis
5. pregnancy
61
What's a normal BUN:Cr
10:1
62
What BUN:Cr ratio would you expect to find in a pt w/ rhabdomyolysis
<10:1
63
You want to check the urine albumin:Cr ratio (UACR) of your pt but do not want to collect a 24hr urine to determine it. What is a reliable alternative test for getting this info
a "spot" UACR
64
How is GFR determined
clearance of creatinine from kidneys (CrCl)
65
test of kidney function in pt's w/ DM anually
albumin:creatinine
66
What (2) factors directly influence the clearance of a substance from the nephron
1. plasma concentration of substance
| 2. excretory rate of nephrons
67
Why is Cr clearance (CrCl) a more reliable clearance marker for GFR than urea
it has a more constant production rate than does urea
68
*What is considered the most reliable test of renal function
Serial CrCl measurements
69
At what time of day would one find the highest CrCl
Afternoon
70
what does a CrCl of 35 ml/min/1.73 m2 signify
Renal insufficiency
71
what is the major dx utility for measurement of urine Na+
integrity of nephron tubule for absorption--assess for acute oliguria, hyponatremia, and volume depletion
72
T/F A clean catch urine is required to accurately measure the urine Na+
F
73
Of what utility is a fractional excretion of Na+ (FENa) in your work-up of a renal dz pt
differentiate renal failure to:
1. pre-renal cause
2. acute tubular necrosis ATN
74
T/F Pt's w/ acute tubular necrosis ATN excrete less Na+ thus their FENa is low
F--in ATN there is sig tubular epithelial damage thus reabsorption of Na+ is hampered and susequently the FENa is higher >2
75
Pre-renal azotemia FENa
<1
76
What is urine osmolality a measure of
mOsm/kg of solution--evaluation of the concentrating capabilities of pt's kidneys
77
How are urine osmolality and urine specific gravity related
related in that the # of molecules present in the urine (urine osmolality) is a major determinant of its weight (SG)
78
Briefly , how does US tech work
cross-sectional view of anatomic structure using ^ fq waves from vibrated crystal--reflected echoes recorded
79
what advantage does Doppler US have over conventional US
allows for appreciation of blood flow direction and magnitude of the velocity in structure under eval
80
List (5) stiuations where you would want to use US
1. Hematuria (painless/painful) 1st choice
2. AKI/CRF --assess size + exclude hydronephrosis
3. Renal abscess--1st choice CT
4. UTI--
5. Polycystic kidney disease (PCKD)--US or CT
81
Why does the US tech ask the pt to drink lots of fluids prior to having a pelvic US
the filled bladder displaces the air-filled bowel from the region of interest in pelvis
82
Of what utility is a CT angiogram in evaluating pt's for renal dz
in assessing the renal arteries for atherosclerosis and also as a tool to assess renal blood flow in assessing kidneys for renal transplant
83
What is the main reason you'd order an MRA
to assess your pt for renal artery stenosis
84
what might be the 1st clue for renal artery stenosis
hearing a bruit over the renal arteries when auscultating
85
List (5) conditions which would warrant order a renal Bx
1. hematuria
2. proteinuria
3. renal impairment
4. pre-renal transplantation
5. nephrotic syndrome
86
In which pt's would a Voiding Cystourethrogram VCUG be of utility in the work-up
dysuria, infx (infants/children), cystitis, urinary incontinence, vericoureteral reflux
87
(5) conditions what would warrant the ordering of an excretory urogram
1. hematuria
2. severe flank pain
3. cystits
4. bladder outlet obstruction
5. neurogenic bladder
88
What should be reviewed prior to performing a cystoscopy
pt's meds look for: warfarin, ASA, or other blood thinners
89
A retrograde urethrogram RUG is order to assess
structural abnormalities in the urethra
90
When should a RUG always be performed
prior to transurethral catheterization in a pt suspected of having urethral injury
91
In what pt's should Captopril renography be limited (2)
1. pt's w/ elevated Cr >2.0 mg/dL
| 2. pt's w/ advanced atherosclerosis
92
What study, when normal, excludes the dx of renovascular hypertension
Captopril renography
93
Describe the stages of creatinine change expected in a pt w/ contrast nephropathy
1. serum Cr increase 24-48 hrs post contrast exposure
2. peaks at 3-5 days
3. resoves within 1 wk
