basic examination of urine Flashcards
1
Q
how much blood perfuses the kidney each minute ?/
A
1200ml = 25 percent of cardiac output
2
Q
what is basic urine analysis ?
A
specimen evaluation
gross/physical evaluation
chemical screening
sediment examination
3
Q
what are the types of urine probe ?
A
the first retractable urine in the morning
single random specimen
24 hour urine collection
4
Q
appearance and colour if urin directed to its diagnosis ?
A
colurless - very dilute
diabetes insipidus - polyurea
cloudy - phosphates ,
carbonates
dissolves with acetic acid
urates and uric acid dissolves at 60 degrees in alkaline
leukocytes bacteria spermatazoa prostatic fluid insoluble in acetic acid
milky
neutrophils -pyuria
lipidurea - nephrotic syndrome , fractures of major long bones
soluble in ether
chylurea - lymphatic obstruction soluble in ether
causes parasitic infections - wuchereria bancrofti / abdominal lymph node enlargemet / tumors
paraffin based vaginal creams
yellow /orange -
concentrated - dehydrated
urobilin in excess
yellow /green
bilirubin/ biliverdin
yellow brown
bilirubin / biliverdin
red / brown hemoglobin erythrocytes myoglobin reagent strip for blood positive
brown black
methhemoglobin
melanin
uric acid and urates can be white , pink , orange
5
Q
urin door of extensive bacterial overgrowth ?
A
ammoniacal fetid odour
6
Q
Lack of odor in urine from patients with acute renal failure suggests
A
acute tubular necrosis
7
Q
The average adult produces how much urine per day ?
A
600–2000 mL
night - less than 400ml
8
Q
Production of more than 2000 mL of urine in 24 hours is termed?
A
polyurea
9
Q
excretion of more than 500 mL of urine at night with a specific gravity of less than 1.018 is called?
A
nocturea
10
Q
causes of polyurea?
A
diabetes insipidus :
pituatory gland not producing enough adh
renal unresponsivness
15L of urin
Defective Renal Salt/Water Absorption
administration of diuretic agents, abnormality of the renal tubules, progressive chronic renal failure.
Osmotic Diuresis- diabetes mellitus with hyperglycemia
11
Q
cause of decrease in urine volume ?
A
water deprivation, acute renal failure, chronic progressive renal disease
prerenal - chf
sepis
renal artery stenosis or embolic occlusion
post renal - bilateral hydronephrosis
prostatic hyperplasia
bilateral ureteral obstruction - sones
renal - glomerulonephritis
acute tubular necrosis
chronic renal failure - hypertension - nephroscelerois diabetes -associated nephrosclerosis
interstitial nephritis
12
Q
methods for measuring specific gravity ?
A
reagent strip ,
refractometer
urinometer
falling drop method
13
Q
most of the specific gravity of urine is done by ?
A
urea
sodium chloride
sulfate
phosphate
14
Q
what is the normal specific gravity of urine ?
A
1.003-1.035
15
Q
urine of low specific gravity is called what ?
A
hyposthenuric less than 1.007
16
Q
cause of low specific gravity ?
A
diabetes insipidus ,
pyelonephritis
glomerulonehritis
17
Q
what is the cause for high specific gravity / hypersthenourea ?
A
dehydration - diarhhea , sweating , emesis
glucourea
RAS - renal artery stenosis
adrenal insufficiency
hepatorenal syndrome - decreased flow of blood to kidneys
CHF - decreased blood to kidney
18
Q
what s isothenuria and what is t indicative for ?
A
little or no variability in specific gravity around 1.010
indicative for severe renal damage
concentrating and diluting abilities lost
such as in loop of henle
19
Q
what is the normal osmolality in urine ?
A
500-850 mosm/kg water
20
Q
what is the method of evaluating osmolality ?
A
the freezing point depression method
21
Q
for chemical screening of urin what is used ?
A
reagent strips are primarily used
automated instruments available
22
Q
in healthy individuals what is the urin ph ?
A
4.6-8
23
Q
what is the cause of an acidic urine?
A
diet high in meat protein
fruits such as cranberries
metabolic or respiratory acidosis
higher amount of ammonium ions released
24
Q
what is the cause of alkaline urine ?
A
diet high in fruits and veg especially citrus
metabolic alkalosis
respiratory alkalosis
increased excretion of bicarbonate in both cases
25
what is the method of checking urine ph ?
reagent strip or Ph electrode
26
how much protein is excreted daily ?
150mg
| 2-10 mg/dl conc
27
most of the urin protein excreted is what ?
1/3rd is albumin
Tamm - horsfall glycoportien secreted by DCT and cells of ascending loops of henle - 1/3rd or more
the remaining globulins -a , b and y
```
small amounts:
plasma proteins with molecular weight less than 50,000 - 60,000
retinol binding
b2 microglobulin
immunoglobulin light chains
lysosmes
IgA
```
28
reagent strip method is senstive o which type of proteins in urine?
only albumin
29
what method is used to detect the albumin and globulins and every other proteins in urine ?
acid precipitation
| electrophoretic separation of urine protein
30
what is functional porteinurea ?
less than 0.5g /day protein
transient increase in urinary protein excretion caused by changes in glomerular hemodynamics
RESOLVES with appropriate treatment within 2-3 days
31
what is the cause of functional porteinurea ?
```
dehydration
excersise
congestive heat failure
cold exposure
fever
postural or orthostatic poteinurea
```
32
in whom can we see transient proteinuria?
seen with normal history , normal kidney and normal physical examination occasionally
Normal pregnancy - any porteinurea in pregnancy will need investigation - ABNORMAL
33
persistant portein urea of 1-2g/day n any asymptomatic person has what ?
poorer prognosis than transient intermittent or postural prteinurea
esp accompanied by heamturea
34
what is the range for heavy porteinurea and what causes it
more than 4g /day
nephrotic syndrome (low serum albumin level , general edema , increased serum lipids - tag , cholesterol)
acute , rapidly progressive , chronic types glomerlunephritis - accompanied by erythrocyte casts
see erythrocytes and casts
malaria / sickle cell
malignant hypertension
neoplasia
toxaemia of pregnancy
heavy metal
drug - penicillin
35
what is the range of moderate porteinurea and what causes it ?
1-4g /day
causes - nephrosclerosis
multiple myeloma
toxic nephropathy
degenerative/malignant / iflammatory conditions of the LUT such as presence of calculi
36
what is the range of minimal proteinureaand what is the cause ?
less than 1g /day
```
cause - chronic pyleonephritis
nephrosclerosis
chronic interstitial nephritis
polycystic disease
meduallary cystic disease
RENAL TUBULAR DISEASE!
```
interstitial nephritis - erythrocytes , leukocytes and tubular cells may be seen
37
how can glomerulopathies cause heavy porteinurea ?
loss and reduction of the fixed negative charge of the basement membrane allows albumin to permeate into bowman capsule more than they can be reabsorbed
other similar size lost - antithrombin , transferrin , pre albumin
tubular function still intact - very small plasma protein are absorbed largely
also large proteins are absoluetley not seen in urine while the glomerulus is still selective such as a2 macro globulin
b-lipoprotein
larger proteins appears the proteinuria is less selective indicating greater damage to the glomerulus - such as membranous nephropathy and proliferative glomerulonephritis
38
what is tubular pattern of proteinuria associated with
associated with small amount of urinary protein that would otherwise be largely reabsorbed
often low molecular weight -a micro globulin , b globulin , b2 micro globulin , light chain immunoglobulin and lysosomes
without a predilection for albumin sized molecules
renal tubular diseases - FANCONI SYNDROME, WILSON DISEASE , CYSTINOSIS , PYELONEPHITIS AND RENAL TRANSPLANATION REJECTION
about 1-2g/day
39
which type of prteiurea maybe missed in reagent strip ?
tubular proteinuria because of very low albumin levels or absence
but detected in acid precipitation method
40
what is bench jones prteinurea associated with ?
multiple myeloma , macroglobulinemia and malignant lymphomas
41
bence jones porteinurea is missed if what is used to diagnose it ?
only a reagent strip is used
need to use electrophoresis and immunofixation electrophoresis
immunoassay measurement of light chains
42
what is the pathophysiology of bench jones porteinurea ?
excretion of bench jones protein in are amount causes the tubular cells to deteriorate because of the high levels of protein be reabsorbed
damaged kidney called - myeloma kidney
causing less reasorbition of proteins
and nephrotic syndrome may follow
43
what is the definition of microalbuminurea
presence of albumin in urine above normal level but below the detectable level of urine dipstick method
44
what is the cause of microalbuminurea ?
lower levels of albumin ranging from 20-200mg/L indicator for early and reversible glomerular damage
diabteic patients (micoalbuminurea associated with four to sixfold increase of cardiovascular mortality and renal mortality risk)
more prevelant in hypertensive
45
what is the method of testing in micoralbuminurea ?
immunologic testing and dye binding chemical test strips
46
what is the term for glucose in urine ?
glycoseuria
47
what is the cause for glycosuria ?
glucose level in blood surpasses renal table capacity of reabsorption
usually when glucose level in the blood is greater than 180-200mg/dl
due to diabetes
but does not have to be concomitant with hyperglycaemia
48
what influences the appearance of glycosuria ?
glomerular blood flow
tubular reabsoprtion rate
urine flow
49
what diagnoses method is used for glycosuria ?
urine dipstick
| can identify also gravitas at increased risk for gestational diabetes
50
what are the cases for ketones in urine ?
diabetic ketonurea - diabetes type 1
non diabetic ketoneurea
lactic acidosis
(acetone, acetoacetic acid 3- hydroxybutyrate- any of these three is satisfactory to meet this condition)
51
how can we diagnose ketonuria ?
in urine - reagent strips
| tablets reacting to 10mg of acetoacteic acid per decilitre
52
how can asymptomatic microscopic hematurea be him detected ?
dipstick testing - 16 percent of screening population
53
what is the causes for hematurea ?
```
membranous nephropathy
IgA nephropathy
non IgA mesangioproleferative glomerulonephritis
focal glomerulosclerosis
neoplastic
calculi
anticogulant usage
cyclophosphamid
urinary tract infections
```
54
what is the downfall in using the reagent strip or dipstick method to asses hematurea or hemoglobinurea ?
interfering substances, commonly ascorbic acid, and this problem emphasizes the need for a routine microscopic examination to screen for hematuria.
55
what is the cause of hemoglobinurea
indicates significant intravascular HEMOLYSIS as opposed to extravascular hemolysis.
hemolytic anemia
erythrocyte trauma - prosthetic cardiac valves
ostium primum repair - turbulence
extensive burns
organisms - malaria , bartonella , clostridium welchii toxin
erythrocyte enzyme deficiency- glucosa -6 -phosphate deficiency - exposure to oxidant drugs -sulfamethazole
antimalarial
fava beans - with diabetic acidosis and infection
unstable haemoglobin disease - exposure to oxidant drugs
56
in moderate hemolysis what is present in the urine test
conugated bilirubin is absent
urobilinogen is normal or elevated
hemoglobin is absent
hemosiderin is absent
57
in moderate hemolysis what is the plasma levels
bilirubin is elevated
haptoglobin is decrease
hemoglobin is elevated
58
in marked hemolysis what is found in urine?
```
bilirubin is absent
urobilinogen is elevated
hemoglobin is present
hemosiderin is present l
but in late stages
```
59
in marked hemolysis what is found in plasma levels ?
bilirubin is elvated
haptoglobin is absent
hemoglobin is elevated (markedly)
60
what is the differentiation between hematuria , hemoglobinurea and myoglobinurea
hematurea
plasma colour: normal
```
urine :
color - smoky or pink , red , brown
many erythrocytes ,
if the initial specimen contain red blood cell - urethra
last specimen having it - bladder
all specimens have red blood cells - upper urinary tract or bladder
lower urinary tract - no cell casts
protein can be present or absent
```
renal - there is red blood cell casts and protein increase
hemoglobinuria
plasma color - pink early
haptoglobin low
```
urine -
color - pink , red , brown
erythrocytes occasionally
pigment casts - occasionally
protein - present or absent
hemosiderin - late
```
```
myoglobinurea
plasma
colour - normal
haptogobin - normal
creatin kinase - marked increase
aldolase - increased
```
```
urine
colour - red , brown
erythrocytes - occasional (dense brown?)
casts - occasional
protein present or absent
```
61
This conjugated form of bilirubin is called
direct bilirubin
62
increased bilirubinurea is caused by
alkalosis
bilirubinuria may be present when intracanalicular pressure rises secondary to periportal inflammation, fibrosis, or hepatocyte swelling
Gallstones in the common bile duct and carcinoma of the head of the pancreas
Bilirubinuria is often seen with acute viral hepatitis or drug-induced cholestasis before the appearance of jaundice
typically accompanies jaundice for acute alcoholic hepatitis
exposed to potentially hepatotoxic drugs or toxins, a positive test for bilirubinuria may be an early indication for cholestasis or liver damage
63
congenital hyperbilirubinemias, bilirubin will appear in the urine what types
Dubin-Johnson and Rotor types, and is not present with Gilbert’s disease or Crigler-Najjar disease
64
what are the normal urine and fecal findings ?
urinary bilurubin is absent
urinary urobilinogen is present
decal colour is dark
65
what are the urinary and fecal findings in post hepatic jaundice or obstructive jaundice ?
urinary bilirubin - increased, dark urine
urinary urobilinogen - neoplasm low or absent
gall stones variable
decal colour - pale
with gallstones in bile duct
persistent with neoplasm in duct or pancreas
66
what are the urinary and decal findings in pre hepatic jaundice - haemolytic anemia
urinary bilirubin - absent
urinary urobilinogen - increased
fecal colour is dark
67
what are the urinary and decal findings in hepatic jaundice - hepatitis , cholestasis ?
urinary bilirubin - increased early
urinary urobilinogen - decrease early , and then increased
decal colour is - pale early
and dark late in hepatitis
just pale with cholestasis
68
how does urobilinogen form?
conjugated bilirubin is released into duodenum with cholesterol and bile salts and phospholipids
passes to colon
bacteria hydrolyses there
free bilirubin reduced to urobilinogen , mesobilirubinogen and sterocobilinogen
50 percent of the urobilingen is reabsorbed into the portal circulation , recreated unconjugated into the bile
the remaining urobilinogen excreted in feces as coloured urobilin and sterobilin (by hydrogen removal)
small amount excreted in urine
69
Output of urobilinogen in urine is increased in ?
alkaline urine
decreased in acidic urine
liver is unable to efficiently remove the reabsorbed urobilinogen from the portal circulation,
more urobilinogen than normal is routed through the kidney and hence is excreted in the urine
- viral hepatitis,
drugs, or toxic substances,
some cases of cirrhosis.
congestive heart failure prevents effective urobilinogen handling, and reexcretion into the bile is impaired.
If an infection is present, such as cholangitis associated with obstruction, large amounts of urobilinogen are excreted in urine, together with bilirubin.
70
an excess of urobilinogen in urine together with absent bilirubin is typically associated with
hemolysis -cute lysis of erythrocytes, as well as with destruction of erythrocyte precursors in the bone marrow with megaloblastic anemias
Increased urobilinogen also accompanies bleeding into tissues and the subsequent formation of excess bilirubin.
71
Persistent absence of urinary urobilinogen occurs with?
complete obstruction of the outflow of bile into the intestine, accompanied by pale stools
Broad-spectrum antibiotics, which suppress the normal intestinal flora, may prevent the conversion of bilirubin to urobilinogen
72
two most commonly utilized testing modalities for indirect assessment of bacteriuria and leukocyturia?
reagent strip nitrite and leukocyte esterase
73
“gold standard” for detecting bacteriuria
Microscopic urinalysis serves as a rapid confirmatory test for the presence of leukocytes and bacteria, with bacteriologic culture
74
Many bacteria that are urinary tract pathogens are able to do what ?
reduce nitrate to nitrite
75
Common organisms giving positive nitrite reagent test ?
Escherichia coli, Klebsiella, Enterobacter, Proteus, Staphylococcus, and Pseudomonas
76
which bacteria is unable to produce nitrites ?
Enterococcus
77
If the nitrite test is positive what should follow
culture should be considered
78
what is the procedure urine testing for bacteria in UTI
A first morning clean-voided midstream specimen is best
79
there can be a false negative testing for nitrites in diagnosing bacteria why ?
conversion of nitrate to nitrite by bacterial action in the urine. Because overnight (minimum of 4 hours) bladder incubation is typically required for the infecting bacterial population to convert urinary nitrate to nitrite, a first morning specimen is best
may be due to ascorbic acid, urobilinogen, or low pH (<6)
Random specimens collected during the day and urine from patients with draining catheters
some nitrate- reducing organisms form compounds other than nitrite, such as ammonia, nitric and nitrous oxide, hydroxylamine, and nitrogen, and therefore give a negative nitrite test result.
Lack of dietary nitrate may also produce false- negative results
80
false positiv results for nitrites include ?
poorly collected/stored specimens as the result of contaminants and postcollection bacterial proliferation.
False-positives may also be produced by medications that color the urine red or turn red in an acid medium (e.g., phenazopyridine)
81
numbers of neutrophils in the urine suggests urinary tract infection has difficulty why ?
determining suitable cutoff points for normal and abnormal numbers of these cells. Because quantitative counts are so low, precision is poor
82
Positive leukocyte esterase results correlate with
“significant” numbers of neutrophils
83
in leukocyte esterase results the number of false negative and false positive results are ?
low
84
what may all decrease (false negative) test results for leukocyte esterase
Elevated urine specific gravity, protein, and glucose, boric acid and certain antibiotics such as tetracycline
Very large amounts of ascorbic acid may inhibit the reaction
85
what may give false positive results for leukocyte esterase
Contamination of urine with vaginal fluid
Trichomonas and eosinophils may represent alternative cellular sources of esterases
86
examination of the urine sediment is best reserved and most useful for who?
with abnormal dipstick results
87
Cellular elements are derived from two sources in urine which are?
Desquamated/spontaneously exfoliated epithelial
lining cells of the kidney and lower urinary tract
cells of hematogenous origin (leukocytes and erythrocytes). Cellular and noncellular casts may be seen; these are formed in the renal tubules and collecting ducts
Crystals of variable clinicopathologic significance may also be present.
Organisms (bacteria, fungi, viral inclusion cells, parasites) and neoplastic cells
88
Cells and casts begin to lyse within how may hours of collection and what can prevent it?
2 hours of collection
Refrigeration (2°–8° C) helps prevent the lysis of pathologic entities; however, this may increase the precipitation of various amorphous and crystalline material
89
Midstream collection is recommended for females why?
reduce contamination from vaginal elements.
90
methods for examining urine sediment ?
```
Bright-field Microscopy
• Phase-Contrast Microscopy
• Polarized Microscopy
• Quantitative Counts
• Microscopic Components in Urine Sediment- Erythrocytes, Leukocytes, Transitional (Urothelial) Epithelial Cells, Casts(Hyaline Casts, Waxy Casts, Erythrocyte
```
91
concentrating ability can be considered normal if
random specimen of urine has a specific gravity of 1.023
92
Minimum specific gravity after a standard water load
be less than 1.007
