it's not just water

It’s not just water !It’s not just water !

An introduction to Urinalysis An introduction to Urinalysis

as performed in the as performed in the

Clinical Laboratory.Clinical Laboratory.

Student Objectives:Student Objectives:

Upon completion of this lecture presentation and the laboratory analysis, students will be expected to:

1. Describe the major functions of the kidney.

2. List the major structures of the kidney involved in urine formation.

3. Describe the importance of performingUrinalysis.

Student Objectives - Student Objectives - continued:continued:

4. Observe the various urine elements detected via dipstick chemical analysis.

5. Observe the basic cell types found in the microscopic analysis of urine sediment.

6. Name the clinical laboratory professionals who perform urinalysis testing and explain the education each requires.

TopicsTopics

This presentation covers the following This presentation covers the following topics:topics:– What is Urinalysis?What is Urinalysis?– Review of kidney functionReview of kidney function– Macroscopic examination of urineMacroscopic examination of urine– Chemical examination of urineChemical examination of urine– Microscopic examination of urineMicroscopic examination of urine– Who performs urinalysis testing?Who performs urinalysis testing?– Summary and ReferencesSummary and References

What is Urinalysis?What is Urinalysis?

Urinalysis – or the Urinalysis – or the analysis of urine analysis of urine – is one of the – is one of the oldest laboratory oldest laboratory procedures in the procedures in the practice of practice of medicine.medicine.

It is a good test It is a good test for assessing the for assessing the overall health of overall health of a patient. a patient.

Courtesy of the National Library of Medicine

What is Urinalysis?What is Urinalysis?

It provides information about:It provides information about:– The state of the kidney and urinary tract.The state of the kidney and urinary tract.– Metabolic or systemic (non-kidney) Metabolic or systemic (non-kidney)

disorders.disorders.

Urinalysis can reveal diseases that have Urinalysis can reveal diseases that have gone unnoticed because they do not gone unnoticed because they do not produce striking signs or symptoms. produce striking signs or symptoms. – Examples include diabetes mellitus, Examples include diabetes mellitus,

various forms of kidney failure, and various forms of kidney failure, and chronic urinary tract infections.chronic urinary tract infections.

Review of Kidney Review of Kidney FunctionFunction

Urine is composed of approximately 96% Urine is composed of approximately 96% water and 4% dissolved substances derived water and 4% dissolved substances derived from food or waste products of metabolism.from food or waste products of metabolism.

The actual composition of urine varies, The actual composition of urine varies, depending on diet, metabolism, general depending on diet, metabolism, general health of the body, and health of the kidney.health of the body, and health of the kidney.

Urinalysis is performed to assess the urine’s Urinalysis is performed to assess the urine’s composition as well as kidney function.composition as well as kidney function.

Review of Kidney Review of Kidney Function Function Recall the urinary system consists Recall the urinary system consists

of two kidneys, two ureters and of two kidneys, two ureters and the bladder. the bladder.

Review of Kidney Review of Kidney Function Function Also recall the role of blood - to bring Also recall the role of blood - to bring

nutrients and oxygen to cells of the nutrients and oxygen to cells of the body and to carry waste materials body and to carry waste materials away from those cells.away from those cells.

The kidney has the largest role in The kidney has the largest role in controlling the chemical composition controlling the chemical composition of the blood in order to maintain of the blood in order to maintain proper cell function in the body. proper cell function in the body.

Review of Kidney Review of Kidney Function Function

In the kidney, In the kidney, blood blood undergoes undergoes filtration and filtration and dialysis to dialysis to separate waste separate waste compounds that compounds that will be removed will be removed from the body from the body from those that from those that will be returned will be returned to the to the circulating circulating blood.blood.

Figure 1

Review of Kidney Review of Kidney Function Function More specifically, the kidney has the More specifically, the kidney has the

functions of: functions of: – removal of waste products from the bloodremoval of waste products from the blood– retention of nutrients such as proteins retention of nutrients such as proteins

and glucoseand glucose– maintenance of acid-base balancemaintenance of acid-base balance– regulation of water and electrolyte (salt) regulation of water and electrolyte (salt)

content of the bodycontent of the body– hormone synthesishormone synthesis

Review of Kidney Review of Kidney FunctionFunction Urine is formed in Urine is formed in

the kidney structure the kidney structure called the nephron.called the nephron.

Each kidney Each kidney contains about one contains about one million nephrons.million nephrons.

The nephron is The nephron is made up of a made up of a glomerulus and a glomerulus and a set of tubules.set of tubules.

Cross section of a nephron

Review of Kidney Review of Kidney FunctionFunction

The tubular portion of the nephron consists The tubular portion of the nephron consists of several structures: of several structures: – Proximal convoluted Proximal convoluted

tubule tubule– Loop of HenleLoop of Henle– Distal convoluted Distal convoluted

tubule tubule– Collecting ductCollecting duct

Review of Kidney Review of Kidney FunctionFunction Urine is formed through a three phase Urine is formed through a three phase

process of:process of:– FiltrationFiltration– Reabsorption Reabsorption – SecretionSecretion

Review of Kidney Review of Kidney FunctionFunction Filtration Filtration of the blood occurs within the specialized of the blood occurs within the specialized

collection of capillaries in the glomerulus.collection of capillaries in the glomerulus. The glomerulus permits water and small molecules and The glomerulus permits water and small molecules and

ions from the blood to enter a surrounding tubule called ions from the blood to enter a surrounding tubule called the Bowman’s capsule. This is called the the Bowman’s capsule. This is called the filtratefiltrate..

Blood cells and large protein molecules remain in the Blood cells and large protein molecules remain in the blood and return to the venous circulation. blood and return to the venous circulation.

Review of Kidney Review of Kidney FunctionFunction Reabsorption Reabsorption of essential chemicals the of essential chemicals the

body needs (glucose, amino acids, NaCl body needs (glucose, amino acids, NaCl and other salts, water and vitamins)and other salts, water and vitamins) occurs occurs within the nephron’s proximal within the nephron’s proximal tubule, Loop of Henle, and distal tubule.tubule, Loop of Henle, and distal tubule.

Reabsorption Reabsorption prevents the loss of prevents the loss of necessary body compounds but also necessary body compounds but also adjusts the concentration of urine so it is adjusts the concentration of urine so it is more dilute when the body has more water more dilute when the body has more water (i.e., hydrated) and more concentrated (i.e., hydrated) and more concentrated when the body is short of water (i.e., when the body is short of water (i.e., dehydrated).dehydrated).

Review of Kidney Review of Kidney FunctionFunction SecretionSecretion of foreign chemicals the body of foreign chemicals the body

does not needdoes not need (ammonia, drugs, (ammonia, drugs, hormones, toxins)hormones, toxins) begins in the begins in the proximal tubules and continues in the proximal tubules and continues in the distal tubule and the collecting duct. distal tubule and the collecting duct.

SecretionSecretion of excess ions such as H of excess ions such as H++ and and KK++ help establish electrolyte and acid- help establish electrolyte and acid-base balance.base balance.

Review of Kidney Review of Kidney FunctionFunction All three processes of filtration, reabsorption and secretion All three processes of filtration, reabsorption and secretion

occur simultaneously as a result of complex cellular occur simultaneously as a result of complex cellular transport mechanisms and buffering mechanisms within the transport mechanisms and buffering mechanisms within the nephron tubules. nephron tubules.

The glomerular filtrate becomes more concentrated and The glomerular filtrate becomes more concentrated and acidic after it leaves the distal tubule and enters the acidic after it leaves the distal tubule and enters the collecting duct.collecting duct.

The fluid that leaves the collecting duct is now urine.The fluid that leaves the collecting duct is now urine.

Review of Kidney Review of Kidney FunctionFunction The processes of glomerular filtration and renal tubular The processes of glomerular filtration and renal tubular

reabsorption and secretion are can become affected when the reabsorption and secretion are can become affected when the kidney is compromised by disease.kidney is compromised by disease.

Loss of renal function can be caused by variety of conditions Loss of renal function can be caused by variety of conditions such as:such as:– congestive heart failurecongestive heart failure– injury to the glomerulus or tubules caused by drugs, heavy metals and injury to the glomerulus or tubules caused by drugs, heavy metals and

viral infectionsviral infections– diabetes, hypertension and kidney stones. diabetes, hypertension and kidney stones.

UrinalysisUrinalysis

Renal function tests, such as the Renal function tests, such as the urinalysis, are used to screen for the urinalysis, are used to screen for the cause and the extent of renal cause and the extent of renal dysfunction.dysfunction.

Urinalysis consists of the following Urinalysis consists of the following measurements:measurements:– Macroscopic examMacroscopic exam– Chemical exam Chemical exam – Microscopic exam of the sedimentMicroscopic exam of the sediment

Macroscopic ExamMacroscopic Exam

Examination of Examination of the physical the physical properties properties including….including….– ColorColor– Clarity (or Clarity (or

transparency)transparency)


Color - normalColor - normal– yellow (straw to amber)yellow (straw to amber)

Color - abnormal (due to disease, drugs Color - abnormal (due to disease, drugs or diet)or diet)– pale to colorless pale to colorless – amber (dark yellow)amber (dark yellow)– orange orange – pink or redpink or red– greengreen– brown or blackbrown or black


Clarity (or transparency) - normalClarity (or transparency) - normal– clear

Clarity - abnormal (due to Clarity - abnormal (due to insoluble elements such as cells, insoluble elements such as cells, crystals, etc.)crystals, etc.)– hazyhazy– cloudycloudy– turbidturbid


Left to right: Straw, clear; yellow, clear; yellow, hazy; yellow, clear; red-orange, clear; brown, hazy.

Chemical ExamChemical Exam

The presence of The presence of normal and abnormal normal and abnormal chemical elements in chemical elements in the urine are detected the urine are detected using dry reagent using dry reagent strips.strips.

These plastic strips These plastic strips contain absorbent contain absorbent pads with various pads with various chemical reagents for chemical reagents for determining a specific determining a specific substance.substance.


When the test When the test strip is dipped strip is dipped in urine the in urine the reagents are reagents are activated and a activated and a chemical chemical reaction occurs. reaction occurs.

The chemical The chemical reaction results reaction results in a specific in a specific color change. color change.


After a specific After a specific amount of time amount of time has elapse, this has elapse, this color change is color change is compared compared against a against a reference color reference color chart provided chart provided by the by the manufacturer manufacturer of the strips. of the strips.

Chemical Reaction Chemical Reaction ChartChart


The intensity of the color formed The intensity of the color formed is generally proportional to the is generally proportional to the amount of substance present. amount of substance present.

Typical Substances Typical Substances Tested & SignificanceTested & Significance pHpH - partial assessment of acid base status; - partial assessment of acid base status;

alkaline pH indicates old sample or urinary tract alkaline pH indicates old sample or urinary tract infectioninfection

Specific GravitySpecific Gravity - - state of kidney and state of kidney and hydration status of patient hydration status of patient

ProteinProtein - - primarily detects protein called primarily detects protein called albumin; important indicator in the detection of albumin; important indicator in the detection of renal diseaserenal disease

GlucoseGlucose - - primarily detects glucose (sugar); primarily detects glucose (sugar); important indicator of diabetes mellitusimportant indicator of diabetes mellitus

Typical Substances Typical Substances Tested & SignificanceTested & Significance Blood Blood - red blood cells, hemoglobin, or - red blood cells, hemoglobin, or

myoglobin (muscle hemoglobin); sensitive early myoglobin (muscle hemoglobin); sensitive early indicator of renal diseaseindicator of renal disease

KetoneKetone - normal product of fat metabolism; - normal product of fat metabolism; increased amounts seen in diabetes or starvation increased amounts seen in diabetes or starvation (extreme dieting)(extreme dieting)

BilirubinBilirubin - detects bilirubin (a product of red cell - detects bilirubin (a product of red cell breakdown); indicator of liver function breakdown); indicator of liver function

UrobilinogenUrobilinogen - another by-product of red cell - another by-product of red cell breakdown; increased amounts seen in fever, breakdown; increased amounts seen in fever, dehydration, hemolytic anemia and liver diseasedehydration, hemolytic anemia and liver disease

Typical Substances Typical Substances Tested & SignificanceTested & Significance

NitriteNitrite - certain bacteria convert normal - certain bacteria convert normal urine nitrate to nitrite; indicator of urinary urine nitrate to nitrite; indicator of urinary tract infection tract infection

Leukocyte EsteraseLeukocyte Esterase - - detects esterase detects esterase enzyme present in certain white blood cells enzyme present in certain white blood cells (e.g, neutrophils, monocytes); indicator of (e.g, neutrophils, monocytes); indicator of urinary tract infectionurinary tract infection

Example Chemical Example Chemical Analysis Results ...Analysis Results ...

Elevated pH (alkaline)Elevated pH (alkaline)

(Normal for comparison) (Normal for comparison)

Positive GlucosePositive Glucose


Positive Blood & Positive Blood & KetonesKetones


Positive Blood and Positive Blood and Leukocyte EsteraseLeukocyte Esterase


Microscopic ExamMicroscopic Exam

Most commonly used procedure Most commonly used procedure for the detection of renal and/or for the detection of renal and/or urinary tract disease.urinary tract disease.

This exam consists of reviewing This exam consists of reviewing the solid material suspended in the solid material suspended in the urine - both chemical and the urine - both chemical and cellular. cellular.


Requires a well-trained laboratory Requires a well-trained laboratory professional who is:professional who is:– skilled in the use of various microscopic skilled in the use of various microscopic

techniques such as bright field and phase techniques such as bright field and phase microscopymicroscopy

– able to distinguish normal or contaminating able to distinguish normal or contaminating items from abnormal, pathologic elementsitems from abnormal, pathologic elements

– knowledgeable of the clinical significance of knowledgeable of the clinical significance of each finding and its relationship to the each finding and its relationship to the chemical and physical analysischemical and physical analysis


The urine The urine specimen is specimen is centrifuged centrifuged and the and the liquid portion liquid portion is poured off.is poured off.

The The concentrateconcentrated cellular d cellular sediment …. sediment ….


……. is then . is then placed on a placed on a microscope microscope slide, slide, covered covered with a with a coverslip coverslip and ….and ….


… … viewed under a microscope.viewed under a microscope.


A variety of normal and abnormal A variety of normal and abnormal cellular elements may be seen in cellular elements may be seen in urine sediment such as:urine sediment such as:– Red blood cellsRed blood cells– White blood cellsWhite blood cells– MucusMucus– Various epithelial cellsVarious epithelial cells– Various crystalsVarious crystals– BacteriaBacteria


Red blood cellsRed blood cells– presence of a presence of a

few is normalfew is normal– higher numbers higher numbers

are indicator of are indicator of renal diseaserenal disease

– result of bleeding result of bleeding at any point in at any point in urinary systemurinary system

40x objective


White blood cellsWhite blood cells– a few are normala few are normal– high numbers high numbers

indicate indicate inflammation or inflammation or infection infection somewhere along somewhere along the urinary or the urinary or genital tractgenital tract

40x objective


MucusMucus– look like long, look like long,

ribbon-like ribbon-like threadsthreads

– common finding common finding in urine sedimentin urine sediment

– secreted by secreted by glands in the glands in the lower urinary lower urinary tracttract

40x objective


Epithelial cellsEpithelial cells– cells are large cells are large

and flatand flat– normal cells normal cells

that line the that line the urinary and urinary and genital tract or genital tract or renal tubulesrenal tubules

40x objective


A variety of A variety of normal and normal and abnormal abnormal crystals may crystals may be present in be present in the urine the urine sediment.sediment.


Crystals of calcium Crystals of calcium oxalateoxalate– colorless octahedroncolorless octahedron– found in acid urinefound in acid urine

Crystals of triple Crystals of triple phosphatephosphate– colorless, “coffin-lid” colorless, “coffin-lid”

prism prism – common finding; not common finding; not

clinically significantclinically significant


Hyaline CastsHyaline Casts– colorless and colorless and

fatter than mucusfatter than mucus– a few are normala few are normal– may be increased may be increased

after strenuous after strenuous exerciseexercise

– form when form when protein solidifies protein solidifies in the nephronin the nephron

Hyaline cast & epithelial cell, 40x objective

An additional note ...An additional note ...

The chemical and microscopic analysis The chemical and microscopic analysis of urine can be performed manually or of urine can be performed manually or with automated analyzers.with automated analyzers.

In many laboratories, abnormal In many laboratories, abnormal automated findings are confirmed by automated findings are confirmed by manual techniques.manual techniques.

Who performs Who performs urinalysis testing?urinalysis testing? In most clinical laboratories, In most clinical laboratories,

urinalysis is performed by medical urinalysis is performed by medical laboratory professionals called:laboratory professionals called:– Medical Laboratory Technicians or Medical Laboratory Technicians or

Clinical Laboratory Technicians Clinical Laboratory Technicians (MLT/CLT) (MLT/CLT)

– Medical Technologists or Clinical Medical Technologists or Clinical Laboratory Scientists (MT/CLS)Laboratory Scientists (MT/CLS)

What education is What education is required to be a required to be a laboratory professional?laboratory professional? Associate’s degree Associate’s degree

– Medical Laboratory Technician (MLT)Medical Laboratory Technician (MLT)– Clinical Laboratory Technician (CLT)Clinical Laboratory Technician (CLT)

Bachelor’s degree Bachelor’s degree – Medical Technologist (MT)Medical Technologist (MT)– Clinical Laboratory Scientist (CLS)Clinical Laboratory Scientist (CLS)

For more info, visit our web site atFor more info, visit our web site atwww.medlabcareers.msu.eduwww.medlabcareers.msu.edu

Laboratory science Laboratory science careers are rated careers are rated among the best!among the best!

Website managerWebsite manager ActuaryActuary Computer systems analystComputer systems analyst Software engineerSoftware engineer MathematicianMathematician Computer programmerComputer programmer AccountantAccountant Industrial designerIndustrial designer Hospital administratorHospital administrator Web developerWeb developer Paralegal assistantParalegal assistant

Parole officerParole officer MeteorologistMeteorologist Technical writerTechnical writer Medical secretaryMedical secretary

Medical technologistMedical technologist Financial plannerFinancial planner

Medical laboratory Medical laboratory techniciantechnician

AstronomerAstronomer HistorianHistorian

Jobs Rated Almanac, L. Krantz, 1999

Summary Summary

Urinalysis in an important clinical diagnostic Urinalysis in an important clinical diagnostic test. test.

Urinalysis can reveal diseases that have gone Urinalysis can reveal diseases that have gone unnoticed because they do not produce unnoticed because they do not produce striking signs or symptoms.striking signs or symptoms.

Urinalysis provides information about the Urinalysis provides information about the kidney, urinary tract, and systemic (non-kidney, urinary tract, and systemic (non-kidney) disorders.kidney) disorders.

The results of the macroscopic, chemical and The results of the macroscopic, chemical and microscopic analysis must be interpreted microscopic analysis must be interpreted together to arrive at a proper diagnosis. together to arrive at a proper diagnosis.

Summary Summary

Although urinalysis is easily performed Although urinalysis is easily performed with reagent test strips, the results are with reagent test strips, the results are dependent on:dependent on:– correct technique correct technique – an understanding of the limitations and an understanding of the limitations and

interference'sinterference's Thus, technologists and technicians Thus, technologists and technicians

performing these tests must be properly performing these tests must be properly trained, especially in correctly recognizing trained, especially in correctly recognizing microscopic elements.microscopic elements.

References References

Urinalysis and body fluids - a colortext and Urinalysis and body fluids - a colortext and atlasatlas, Ringsrud, K & Linne, J, Mosby - Year , Ringsrud, K & Linne, J, Mosby - Year Book, Inc., 1995.Book, Inc., 1995.

MTS MTS Lab Training Library™Lab Training Library™, University of , University of Washington, Department of Laboratory Washington, Department of Laboratory Medicine, 2003. Medicine, 2003.

Modern chemistryModern chemistry, Bayer Corporation, , Bayer Corporation, Diagnostics Division, Tarrytown, NY, 1996.Diagnostics Division, Tarrytown, NY, 1996.

MultistixMultistix 10SG Urinalysis Reagent Strips 10SG Urinalysis Reagent Strips product insert AN30516C, Bayer product insert AN30516C, Bayer Corporation, April, 1999.Corporation, April, 1999.

References References

Figure 1: Figure 1: Your Kidneys and How They Your Kidneys and How They WorkWork, National Kidney and Urologic , National Kidney and Urologic Diseases Information Clearinghouse,Diseases Information Clearinghouse,http://www.kidney.niddk.nih.gov/kudiseases/pubs/http://www.kidney.niddk.nih.gov/kudiseases/pubs/yourkidneys/index.htmyourkidneys/index.htm

Figure 2:Figure 2: Update in Anaesthesia - Update in Anaesthesia - Physiology of the Kidney, Physiology of the Kidney, Issue 9 Issue 9 (1998) Article 6, World Anaesthesia (1998) Article 6, World Anaesthesia (WA) and World Federation of Societies (WA) and World Federation of Societies of Anaesthesiologists (WFSA), of Anaesthesiologists (WFSA), http://www.nda.ox.ac.uk/wfsa/html/u09/u09_016.htmhttp://www.nda.ox.ac.uk/wfsa/html/u09/u09_016.htm

The EndThe End

Students:Students:– Perform a “Chemical Analysis” on the Perform a “Chemical Analysis” on the

urine “specimens” provided by your urine “specimens” provided by your teacher. teacher.

Teachers:Teachers:– After students complete chemical After students complete chemical

analysis, show students the following analysis, show students the following Microscopic Images for the “Microscopic Microscopic Images for the “Microscopic Analysis” portion of the lesson.Analysis” portion of the lesson.

It’s not just water !It’s not just water !

Microscopic Images Microscopic Images

forfor

Urinalysis Laboratory LessonUrinalysis Laboratory Lesson

Patient #1 -Patient #1 -40x objective40x objective

Patient #2 -Patient #2 - 100x objective100x objective

Patient #3 -Patient #3 -100x objective100x objective

Patient #4 Patient #4 - - 40X objective40X objective

it's not just water

Documents