Exam A Blakes Flashcards
What pertinent facts must be considered when trying to establish normal ranges for any clinical lab?
You must consider your patient’s age and the reference intervals you are measuring.
The age of the population you are dealing with and their gender
What is the main specimen being run on it, such as what anticoagulant is being used?
Time of collection
Venipuncture time and if a tourniquet is used, such as when you measuring lactic acid, make sure you leave the tourniquet off because it can inflate the values.
- Which parameters are measured directly on the automated cell counter in this hematology laboratory and how are they measured?
RBCs, WBC, Hemoglobin,
- Which parameters are calculated values?
MCV, MCH, MCHC, Hct,
- Calculate CBC indices when possible using given information.
MCV= HCT/RBC * 10
Hct= (MCV * RBC)/ 100
MCHC= Hgb/Hct* 100
MCH= Hgb/RBC* 10
- How does electrical impedance work as a means of automated cell counting?
Electrical impedance works by counting the cells by the resistance given off when they cross the cell aperture. A cell with an increase in resistance will have an increase in impedance.
- List 3 sites from which bone marrow aspirates can be obtained. (These sites may differ between adults & children.)
The proximal ends of the long bones
Vertebrae( 3rd)
iliac crest ( 1st preference Adults and children)
Tibia( neonates 4th proximal)
Sternum (2nd only adults)
- Name three findings used to verify that bone marrow has been obtained from an aspirate, rather than peripheral blood
Presence of immature cells
presence of fat
presence of bone spicules
- List the hemogram parameters and the significance of each.
The hemogram includes the RBC count, WBC count, the Plt count, the Hgb count
the MCH, MCHC, and MCV.
The RBC count will be lower in Sideroblastic anemia, IDA, Aplastic anemia, lead poisoning, some leukemias, and in thalassemia.
The WBC count will be low in certain infections and HIV, and burns.
The plt count will be low in splenomegaly conditions, in DIC, in aplastic anemia, in certain bone marrow cancers, in myelopathic anemias,
The MCV will be high in certain leukemias, in megaloblastic anemia, and in B12 and folate deficiencies.
- What action/s should be taken if the linearity on the analyzer were exceeded?
Run a dilution of 1:7
A differential should be run if a value is outside the linearity range for WBCs.
Except if a lymphocyte count is over 50%= albumin smear, differential
for Plts remove the clot and then rerun for distribution errors.
For RBCs= if you have a low RBC count and high hemoglobin, then you should use a heat bath and check for cold agglutinates; if you have an abnormal RBC count and there being counted as plts; then recollect in sodium citrate( blue tube and multiply by 1.1.
- Compare and contrast controls and calibrators, including their definition and proper usage
Calibrator; a material of known value used to standardize any analytical procedure and thereby determine the value of an unknown
used for verifications/ Validations
Controls a stable substance that contains one or more known constituents used to verify the accuracy and precision of a method
- used for runs; are used for lot-lot validations
- Define reference ranges for CBC parameters at your institution.
WBC= 0-400 K/ul
Hct= 0-75.0%
NRBCs=o-600/100nRBCs
Rets=0-30%
RBCs= 0-8.60m/uL
- What is the proper corrective action for: cold agglutinins, lipemia, out of range results?
If you have a low RBC count and high hemoglobin, then you should use a heat bath and check for cold agglutinates; if you have an abnormal RBC count and there being counted as plts, then recollect in sodium citrate( blue tube and multiply by 1.1 also with plt satellitosis.
If you have lipemia, you should automatically rerun with a dilution or you can do plasma replacement( on heme powerpoint)
If you have an out of range results( rerun with a dilution ( a 1:7 dilution)
Pa
- What criteria makes a specimen unacceptable for CBC analysis?
A mislabeled specimen without a request form, wrong tube with anticoagulant, wrong medical records number.
- Compare different cellular morphology and function of WBCs, RBCs, and platelets.
WBCs functions are to stop foreign invades in the body, you have phagocytes such as Macrophages( best) –> neutrophils(2nd)—> dendritic cells—> eosinophils—> basophils.
by mobility–> neutrophil( 1st)–> Macrophage—> then eosinophil—> basophil
- Compare the normal blood cell and hemoglobin proportions for adults, infants, and children.
Segs
% of segs in Newborns= 50-70%
% of segs in Children= 28-45%
% of segs in Adults= 50-70%
Bands%
15-35% in newborns (3-11)
0-5% in children (0-5)
0-5% in adults ( 2-6)
Eosinophils%
newborns: 0-5%
children: 0-8%
Adults: 0-5%
Basos%
newborns, children, and adutls= 0-1%
Lymphs%
lymph: 10-20 newborns, 35-65 children, 20-40 adults
- Explain the purpose of hematological testing, including CBC, ESR, Retic Counts, etc.
CBC is used to find the indices such as RBC, WBC, and hemoglobin that aid in identifying specific disease states.
ESR test
Used to find the inflammatory conditions in the body( RBCs fall because they overcome their repulsion forces called zeta potentials and form rouleaux; this then forces the RBCs to fall fastest down because they have a higher density.
An increase in ESR is caused by increased plasma proteins, an increase in plasma viscosity, and the presence of rouleaux.
A decrease in rouleaux is caused by an increase in whole blood viscosity and a decrease in plasma protein concentrations.
Whole blood collected in 0.5 mg/ml EDTA is specimen of choice
westergren reference ranges: males: 0-15mm/hr
females: 0-20mm/hr
What conditions are present with a decrease In ESR
Hypofibrinogenemia, CHF, polycythemia, RBC morphological abnormalities such as anisocytosis, pokilo, spherocytes, and MM/ WM.
Retic counts
are done when the cell is alive and uses a supravital stain called new methylene blue.
count retics in 1000 cell and then divide by 10
uses a miller disk to count
- Which CBC values are useful in predicting the peripheral blood picture and how are they interpreted?
The CBC values are useful in predicting the Peripheral blood picture are the Retic value, the MCV, then the MCH and MCHC.
- What is the proper action taken when the following are found in specimens?
a. Platelet clumping
b. nRBCs
c. clotted specimen
The appropriate action to take when there is platelet clumping is to get fibrin sticks look for a clot, and then rerun the specimen. If this doesn’t work then you can collect in sodium citrate and multiply by 1.1
For nRBCs do a differential and then if greater than 5 are present use this formula (WBCs * 100/ nRBC + 100)
Clotted specimen : do a automatic rerun and use fibrin sticks to get clot out.
- Explain what is meant by an M:E ratio. Describe a normal M:E ratio and explain how it differs between adults and children.
The M: E ratio states the amount of myeloid to erythroid cells in the bone marrow.
Children/ infant have a M to R ration of 5:1- 6:1
- Identify the purpose of forward angle and side angle light scatter measurements in automation.
Forward scatter indicates cell volume ( wider image device
Side scatter indicates the granularity and internal components s
- List the cytochemical tests and stains that can be performed on bone marrow specimens, and correlate results with their corresponding disease states.
Myeloperoxidase= is a stain that can stain immature granulocytes
Sudan Black B is a more specific stain that can stain immature granulocytes
Both MPO and SSB can be used for mono but the stain will only be 1+
- Correlate typical bone marrow findings and clinical presentation with each of the following conditions. Be sure to include mention of the new drugs, Gleevec, ATRA, Aredia, & Velcade, where applicable:
a. ALL b. AML c. aplastic anemia d. multiple myeloma
- Evaluate the principle, special features, normal and abnormal cellular reactions to the following bone marrow stains:
a. Myeloperoxidase/peroxidase b. Sudan Black B e. Prussian blue
c. Specific Esterase d. Periodic Acid-Schiff
- Explain the principle of the osmotic fragility test and correlate an increased or a decreased osmotic fragility result with the appropriate clinical conditions.
- Diagram the physiologic mechanism of Heinz body formation, and the clinical conditions in which they would occur.
- Compare and contrast Ham’s Test and the Sucrose Hemolysis Test, including the clinical significance of each.
- Explain the principle and possible sources of error of the erythrocyte sedimentation rate (ESR).
- Examine the reference range for ESRs, and the clinical conditions associated with an increased and a decreased ESR.
- What criteria make a Hematology specimen unacceptable for an ESR?
- Explain the principle of the screening test for sickle cell disease, including the phenotypes with a positive test result.
- Evaluate the components and trouble-shoot reactions of the Wright Stain.
- Assess the migration patterns for both cellulose acetate & citrate agar hemoglobin electrophoresis.
- Describe the condition of PCH; include its etiology, pathophysiology (including specific antibody produced), and characteristic lab results
- Which esterase stain is specific, & which cell type does it stain? Which esterase is stain is
nonspecific, & which cell type does it stain? Why do you add fluoride to the nonspecific esterase stain?
- The Tartrate-Resistant Acid Phosphatase (TRAP) stain is positive in what disease?
- Assess the purpose of the following laboratory test with the proper clinical disease state:
a. Osmotic fragility c. Hemoglobin electrophoresis e. Ham’s test
b. Fluorescent spot test d. Reticulocyte count
Amorphous such as amorphous phosphates and urates
is a type of salt and is non crystalline
Amorphous phosphates are soluble in acetic acid, and amorphous urates are not; alkaline urates are present in acidic urine.
amorphous urates are present in acidic conditions and are composed of sodium, potassium, magnesium, and calcium
and they are soluble in alkaline conditions
both have no clinical significance and no defined shape
Anisotropic
materials with different properties
Are composed of ( cholesterol esters) and have a distinct maltose cross appearance under polarizing microscopy but will not stain with a fat stain.
Anuria
The presence of no urine secretion usually indicates renal failure.
Cylindroiduria
Urine sediment that resembles casts but has one end that tapers out like a strand of mucus.
Cystitis
Inflammation of the bladder
Diurnal
Changes of concentration based on the time of day
. Diuresis
An increase in the production of urine
. Ehrlich Unit
Up to 1 mg/dl/2h or Ehrlich unit of urobilinogen is present in normal urine. 2-4 mg/dl are present every 24 hours
Glomerulonephritis
Glomerulonephritis is a sterile inflammatory condition that causes proteins, blood and casts in the urine.
Hyposthenuria
abnormally low osmolality of the urine (abnormally low specific gravity) 1.007 or less
. Isothenuria
The kidney is unable to regulate urine concentration, the urine has a similar specific gravity to protein-free plasma.
Book definition- the urine stays at a constant specific gravity of 1.010 and usually occurs because of renal tubular reabsorption issues.
. Isotropic
the substance maintains the same properties no matter what methods of examination or measurement
Ketoacidosis
Occurs in type two diabetes and is where glucose cant enter the cell, therefore ketone production will increase.
Nephritis
Inflammation of the nephrons and the urine has blood in it.
Nebula
A cloudy appearance in the urine as it cools
Nocturia
Frequent nighttime urination
Oliguria
The production of an abnormally small amount of urine.
Osmolality
is the concentration of a solution expressed as the total number of solute particles per kilogram
. Orthostatic
Occurs when one loses proteins in an upright position but not when lying down.
Polyuria
The excretion of a large volume of urine.
Pyelonephritis
infections of the kidneys with a bacterial infection
Refractive Index
a ratio of the velocity of light in air to the velocity of light in solution
. Specific Gravity
Specific gravity measures the pKa change of polyelectrolytes in relation to ionic concentrations; actually measures ionic concentrations.
Tamm-Horsfall protein
Is a glycoprotein that is the most abundant normal physiological protein in the urine and usually indicates tubular damage.
Primary component of waxy nephron cast
Uremia
Is a raised level urea or creatinine level in the blood and is usually indicative of CKD.
Urochrome
is a pigment causing yellow color of urine
- What is the primary constituent of normal urine?
Plasma filtrate
contains water, electrolytes, hormones, and metabolic waste. Anything smaller than albumin(66kd) can fit in the glomerulus filter.
glomerular filtration rate
Is the rate of plasma volume cleared by the glomeruli per unit of time. The rate can be determined by measuring the Creatinine, the Inulin, or the para-amino hippurate. Creatinine is the most used measurement but Inulin is the reference method.
120ml/min
The reabsorption by the tubules
The proximal tubular is the main absorber and will reabsorb AA, calcium, sodium chloride, potassium, bicarbonate, and glucose.
proteins and glucose are almost completely reabsorbed
threshold substances
is a blood substance that is secreted in the urine and an example of this is glucose only when its plasma concentration exceeds a certain value.
- Name the primary organic constituent of normal urine
The primary organic constituent of urine is urea.
other minor contributors are creatinine and uric acid.
- An unidentified fluid is received in the laboratory with a request to determine whether the fluid is urine or another body fluid. Using routine laboratory tests, how can you determine that the fluid is most probably urine?
Determine the urea and creatinine concentration of the specimen
- Identify the purpose of the following test: creatinine clearance, inulin,
The purpose of the creatinine clearance is to measure The amount of creatinine cleared by the kidneys each minute, therefore to assess renal function indirectly. It is a reasonable estimation of renal function. However, there is a 20% rate that can be counterbalanced by a drug. The reference method for creatinine clearance is the inulin method because it is completely filtered by the kidneys and no reabsorbed.
- List five reasons why a laboratory could consider a urine specimen unacceptable.
Specimen delay
wrong time of day
wrong barcode or label
incorrect placement of the label
the patient was not fasting ( high TGs)
- Write the formula for creatinine clearance. Write the formula for adjusting for body mass.
= UV*UC/PL Con in ml/min
( UV * UC/PC)* 1.73/ * BSA
BSA= sqr( wie( pounds)* height( inc)/ 3131
BSA=sqr(wight( Kg) * height( cm)/ 3600
C=(( U(mg/dl) * V(mg/dl)/ P(mg/dl))* (1.73/ BSA) BSA= .007184*height(cm)^.725 * weight( kg)^.425
- State two parameters of the routine urinalysis that are falsely increased if the specimen is not tested within 2 hours.
Three changes that will affect the microscopic portion are an increased pH, bacteria, nitrate, color, turbidity
- Describe three changes that will affect the results of the microscopic examination of urine that is not tested within 2 hours.
Decreased glucose, decreased urobilinogen decreased ketones, decreased bilirubin, RBCs, and WBCs, cast.
- What is the primary cause of the changes that take place in unpreserved urine?
Bacteria
- Name two chemical parameters not affected by the answer in the question above.
Calcium and urea
- Why is refrigeration the method of choice for preserving routine urinalysis samples?
Because its cheap and easy to place urine cups in the fridge but will effect the amorphous urates
- What chemical can be used to preserve a specimen for a culture and a routine urinalysis? What urinalysis parameter is affected?
Boric acid
Boric acid or tartaric acid. The parameter that is most likely affected by boric acid is the pH( gray tube) Sodium formate
Chloroform
IS not recommended for routine urinalysis because it interferes with urine sediment formation
it can be used for aldosterone
make sure to mix the specimens
Formalin
will increase the proteins in urine and give a false positives
- What is the specimen of choice for routine urinalysis? Why?
first-morning sample and or clean catch
- Will failure to begin a 24-hour urine collection with an empty bladder cause the results to be falsely elevated or decreased?
it will cause results to be falsely increased
- Name three types of urine specimens that would be acceptable for culture to diagnose a bladder infection.
suprapubic
clean catch
catheterization
- When is the kidney stimulated to produce renin? What is the primary chemical affected by the renin-angiotensin-aldosterone system?
The kidney is stimulated to produce renin when there is an decrease in BP or NA++.
The primary chemical affected by the renin-angiotensin-aldosterone complex is Sodium.
- List four substances reabsorbed by active transport and two substances reabsorbed by passive transport.
Four substances absorbed by active transport are glucose, AA, sodium, chloride, phosphorous,
passive transport: water and urea
- List four substances reabsorbed by active transport and two substances reabsorbed by passive transport.
- When the body is dehydrated, is the production of ADH increased or decreased?
Increased
- If a waste product is not filtered at the glomerulus, how can it be removed from the blood?
Dialysis or it can be secreted by the tubules
- Name a chemical that is filtered by the glomerulus and reabsorbed and secreted by the tubules.
Hydrogen
- How does tubular secretion maintain the buffering capacity of the blood?
Hydrogen ions attach to urea to make ammonium which is then excreted out of the urine.
secretion of H ions facilitates reabsorption of bicarbonate
- Why is urine osmolarity more representative of urine concentration than specific gravity?
Urine osmolality represents only the number of solutes that are present in the urine and not any other factors. The specific gravity depends on other factors besides that.
- State the two colligative properties measured by clinical osmometers.
freezing point depression and vapor point depression
- Discuss the renal formation of urine to include
a. constituents of the plasma filtrate
b. glomerular filtration rate
c. reabsorption by the tubule
d. threshold substances
e. function of antidiuretic hormone
f. function of aldosterone
g. tubular secretion
- List 7 types of urine specimens according to method of collection or time of collection.
Suprabubic, random, timed, cath, three glass method, mid-catch stream, postprandial, first morning.
- List 3 urine preservatives and indication for their use.
Chloroform will cause an increase in sediment.
Boric acid will increase the pH
chlorhexidine( yellow-red) tube and will preserve glucose and prevent bacterial growth.
The urine preservatives are Chlorhexidine and formaldehyde for UA and Boric acid for cultures.
- Identify the effect of the following preservatives on the chemical and microscopic findings on a urine sample: refrigeration, toluene, formalin, thymol.
Refrigeration will cause an increase in amorphous urates
Toluene: Preserves ketones and proteins; also, since it floats on the top, it will be difficult to separate the sample from the preservatives
Bacteria ( not effective against bacteria
- How soon should urine be tested after collection?
usually in one hour;
- How soon should urine be tested after collection? What changes occur upon standing at room temperature? Upon refrigeration? Why do these changes occur?
A urine specimen should be tested before 2 hours or refrigerated for 24 hours. Upon standing there will be an increase in color, turbidity, nitrates, odor, bacteria, and pH. There will be a decrease in glucose, ketones, bilirubin, urobilinogen, RBC’s, WBC’s, and casts. Refrigeration will precipitate amorphous phosphates and urates. Most of the changes associated with urine left out is because of bacteria multiplication.
- What collection procedure is preferable for routine urinalysis and why?
the mid catch stream because it is easy to collect and simply done
- List steps in proper collection and timing of a 24 hour urine specimen. What is the normal 24 hour urine volume?
proper collection of 24-hour urine
( give the patient a bucket)
( have the patient fill up a bucket with urine and refrigerate it)
( have the patient deliver the bucket to hospital)
( fill the urine into separate containers and then mix with reagents)
( then store the urine)
A patient receives a container and collection instructions and must always refrigerate the sample. Then the patient delivers the specimen to the lab, and the lab mixes then specimens together and then refrigerates it. The normal volume of a 24-hour urine is 600-1800mL.
- Describe the color of urine associated with the following conditions:
a. Normal
b. hepatic disease
c. porphyria
d. alkaptonuria
e. myoglobinuria
f. hematuria
g. hemoglobinuria
h. melanins
is a clear or pale yellow color
hepatic disease- is a dark orange in color
Porphyria- may be pink in color.
Alkaptonuria- is associated with black urine
Myoglobinuria- Is brown/black color in the urine. Associated with myoglobin present in urine.
Hematuria- the presence of blood or RBC’s in the urine aka the color will be red to brown in color.
Hemoglobinuria- the presence of free hemoglobin in the urine as intravascular hemolysis and the urine will usually be red in color.
Melanins- a dark brown color of the urine.
Identify 4 causes of urine turbidity.
Four conditions that cause turbid urine are mucus, semen, contaminants such as feces and powders, and radiographic contrast media
Identify 4 causes of abnormal urine odor.
Causes of urine odor are bacterial decomposition ( foul ammonia like smell), Ketone( fruity smell), Tyrosinemia( Rancid), and Isovaleric acidemia( Sweaty feet).
Identify the normal pH range of urine. What foods produce acidic urine?
The normal pH of urine is 4.5-8.0. Foods associated with an acidic urine are proteins, some cheeses, and carbonated drinks.
State the normal pH value of urine? What pathologies are associated with persistent acidic and alkaline urine?
The normal pH value is 6
Acidic urine is associated with: starvation, diabetes mellitus, metabolic acidosis, respiratory acidosis, some bacterial infections, uric acid renal calculi
Alkaline urine is associated with: urinary tract infections, renal tubular acidosis, calcium phosphate renal calculi, renal failure
Identify two methods of determining urine pH.
two methods for determining urine pH are reagent strip methods or dip stick methods and a pH meter. Furthermore a refractometer can be used.
Identify the indicator dyes used on the chemical dipstick and their corresponding pH ranges.
The Indicator dyes are methyl red( range of 4-6) and Bromothymol blue(6-9). Acidic urine will be yellow orange and alkaline urine will be green blue.
Identify causes of alkaline and acidic urine and its associated effect on microscopic findings.
- Describe the principles of the following mechanisms of measuring solute concentration in urine:
a. specific gravity-urinometer
b. specific gravity-stix
c. refractive index-refractometer
d. osmolality-vapor pressure
e. osmolality-freezing point depression
- Define specific gravity and identify the purpose of measuring specific gravity. What solids are measured by specific gravity? What conditions cause high specific gravity? Low specific gravity?
- Calculate the effect of protein, glucose and temperature on specific gravity when a urinometer and/or ADTS meter (refractometer) is used?
- What is the relationship of osmolality to specific gravity? Approximately how many milliosmoles equals one unit of specific gravity?
- Describe the effect of the following substances on the copper reduction method and the glucose oxidase method: galactose, fructose, sucrose, lactose, creatinine, uric acid and ascorbic acid.
- What is the significance of protein in urine?
- Identify the origin and composition of Bence Jones protein. What disease processes are they associated with?
- Briefly describe methods for detection of Bence-Jones protein by Toluene-Sulfonic Acid Method and heat method.
- Identify the three ketone bodies. Under what circumstances are ketones formed and how are they excreted?
- Briefly describe the normal pathway of hemoglobin catabolism and expected urinalysis results for bilirubin and urobilinogen in prehaptic, posthepatic and hepatic jaundice.
- What is urobilin?
- Identify the foam test.
- Identify the components of Ehrlich’s aldehyde reagent and its application in the detection of urobilinogen in urine.
- Describe the Watson-Schwartz test for detection of porphobilinogen.
- Briefly discuss the principles, methods, expected results, and indications for performing the following: (include appropriate chemistry tests which might be performed on plasma)
a. urine porphyrins
b. serotonin
c. melanin
d. myoglobin
- What organisms (or groups of organisms) are associated with a positive nitrate reaction? Is the degree of color development proportional to the number of organisms? Does a negative test indicate absence of infection?
- Discuss the principles, sensitivity and specificity of the glucose detection tests to include Clinitest and urine Multistick.
- What is the reason for doing the Clinitest on patients 2 years of age and under?
- Discuss the principle, specificity, and sensitivity of the turbidimetric protein detection tests: sulfosalicylic acid, trichloracetic acid test, Heller’s Ring Test. Specify what kinds of protein are measured and causes of false positive reactions.
- Discuss the dipstix method (solid state) of protein detection to include: “protein error of indicators”, indicators and buffers utilized, sensitivity, specificity and interfering conditions. Specify what type of protein is measured.
- Discuss the Rothera test, Acetest and dipstix methods for detection of ketone bodies in urine to include sensitivity of the method to each ketone body, principle of reaction and reagents required.
- What is the significance of ketones in the urine?
- Compare the Harrison Spot Test and Ictotest with the dipstix methods for the detection of bilirubin to include sensitivity, principle of reaction and reagents required. Also include causes of false negatives and false positives.
- Identify the effect of pyridium on tests for the detection of bilirubin and urobilinogen.
- Discuss the dipstix method for detection of hemoglobin in urine.
- Differentiate between the following and identify the expected hemoglobin dipstix results for each: hematuria, hemoglobinuria, myoglobinuria.
- Discuss the principle, interfering factors and false positives for the stix nitrite reaction.
- Discuss the principle, significance, interference and false positives for the stix leukocyte esterase reaction.
- What are the normal (expected) values for a routine urinalysis?
- Describe the possible impact of a strong positive ketone reaction on the glucose reaction on dipstix. What test is usually performed to detect the error?
- Briefly describe the commonly used Urinalysis automated strip readers (Clinitek, Urotron, Chemstrip) and their principle of operation.
- Why is it important to keep the lid of the dipstick bottle tightly capped?
