Your Practical Guide to Urine Analysis - Cruinn Group

1 your Practical Guide to Urine AnalysisSiemens Healthcare :Layout 1 22/04/2009 09:39 Page 1 Sample First-voided morning Urine isbest for routine Analysis (mostconcentrated). Void directly into clean, drycontainer/bedpan. Sterile containers are best. Label container It is best to test samplesimmediately. If unable to dothis, test within 4 hours. Useuncentrifuged Urine and mixprior to Refrigerate specimenimmediately at 4-8 C, andallow to return to roomtemperature before : It is especially important to usefresh Urine to obtain the bestresults with the tests forbilirubin and urobilinogen, asthese compounds are relativelyunstable when exposed toroom temperature and light. Prolonged exposure ofunpreserved Urine at roomtemperature may result inmicrobial proliferation, withresultant changes in pH. A highly alkaline pH may causefalse positive results with theprotein test area. Urinecontaining glucose maydecrease in pH as organismsmetabolise the glucose.

2 Urea-splitting organisms convert ureato ammonia, causing analkaline shift in pH. Bacterial growth fromcontaminating organisms maycause positive blood reactionsfrom the peroxidases produced. Red and white blood cells maybe lysed upon standing. Thiswill affect microscopy but NOTthe reagent strip a commonly-usedpreservative, in amounts of gm/dl (1 g/L) or greater, maygive false positive reactions foralbumin may give falsepositive results for glucosedeterminations using the tablet Acid acidificationusing concentrated hydrochloricacid is recommended for 24-hoururine collections. This is the mostfrequently-used specimen forsteroid determinations, and willalso preserve cellular acid is generally added forthe preservation of bacteria inurine. However, theconcentration must not beexcessive as this will preventgrowth of bacteria during culture. The leucocyte reagent pad may beinhibited to varying refer to the pack insert forfurther History of Urine Analysis3 Specimen Collection4 Correct Technique for Visual Reading of Reagent Strip Tests5 Quality Assurance6 Chemical Principles of Reagent Strip Tests7 Clinical Significance of Test Results8 Factors Affecting Urine Chemistry Tests on Siemens Reagent Test Strips10 Test Selection Made Easy11 Urinary Tract Infection Testing Pathway 12 Services You Can Rely on for Better Patient CareHistory of Urine AnalysisSpecimen Collection A properly collected urinesample is the first stage inthe generation of qualityclinical information DisclaimerThis is a training Guide and does not replace the package insert for each test.

3 Prior to preparing any test, please read and operate instruments and strips according to Siemens writingsrefer to polyuria. 700 describe honey Urine . 400 uroscopy7th Century diagnosisthrough era of the pisse-prophet. 1674 Thomas Willisrecommendsevaporation,distillation describestest to discoversthat dropsy canbe signalled by aurine urineanalysis consistsof: Visualobservation Test for protein Test for Century Heller developsring test foralbumin. Bence-Jonesdiscovers newprotein. Bird publishesdescription ofurine crystals. Trommerintroduces testfor 19thCenturyEhrlich devisesdiazo reaction 20thCentury Folin introducescolorimetricmethod toestimatecreatinine. 1909 Benedictdevelopsqualitative/quantitative method to Reagent Tabletsintroduced for themeasurement ofreducing test was theforerunner of thewide range ofconvenience urinetests made bySiemens and usedall over the Tests1945 ALBUTEST Reagent HEMATEST Reagent ACETEST Reagent ICTOTEST Reagent Reagent Strips,the first dip-and-read test andKETOSTIX Reagent Strip1960s and 1970sA range of multi-analyte reagenttest strips and 1990sA range ofinstruments forthe automatedand semi-automatedassessment ofmultiple reagenttest strips aredeveloped, whilecontinuallyimproving thereagent launch ofClinitek Status.

4 Asimple, easy touse automatedurine testingsolution. TheClinitek Status provides a fullaudit trail andremoves thesubjectivity ofvisual :Layout 1 22/04/2009 09:40 Page 254 Correct Technique for Visual Reading of Reagent Strip TestsProcedureAlways check the appearance of the Urine sample as it may give useful tests are scientifically designed to react progressively and produce colour changes in the case of positive reactions at the times specified. Accuratetiming is essential for reliable quantitative Don t forget to read thepackage insert carefully Quality AssuranceIt is important to make sure the tests are being used and stored few precautions will ensure meaningful results for patient Chek-STIX for checking reactivity of Siemens test strips procedureChek-STIX strips offer a convenient method of generating an artificial Urine sample which will give a positive or negative result to all Siemensmultiple strip has been developed specifically so the user can be assured of the reactivity of the reagent areas of Siemens multiple reagent strips.

5 Theproduct may also be used as a check of user technique as well as an aid to control solution generated by Chek-STIX Positive solution gives results on Siemens strips in the same manner as Urine specimens. If the stripsare reacting properly a positive result will be seen on each test area, with expected values as shown in the pack Place 12 ml of distilled water in test tubeprovided, by filling to graduation totally one Chek-STIX Cap tube tightly. Invert the tube gentlyback and forth for2 minutes. Allow to stand for30 Invert tube once more. Remove and discardChek-STIX strip. Solution is now ready totest reactivity of Siemens strips or notDo read package insertcarefully before testingDo replace capimmediately and close tightlyDo check expiry date onbottle before useDo not removedesiccant from bottleDo not touch test areasof the stripDo not take out morestrips than are requiredfor immediate use Expected results maychange from the check the packinsert Precautions Expected to g/LPositive Colours may be atypicalPositivePositiveExampleGlucoseBi lirubinKetonesSpecific GravityBloodpHProteinUrobilinogenNitrite Leucocytes1.

6 Completely immerse allreagent areas into fresh, well-mixed, uncentrifuged briefly and removeimmediately to avoiddissolving out While removing the strip, runthe edge against the rim of theurine container to removeexcess Urine . Hold the strip ina horizontal position toprevent possible mixing ofchemicals from adjacentreagent areas or soiling ofhands with After the appropriate time,compare test areas closelywith the corresponding colourchart on the bottle label orbench reader at the timespecified. Hold strip close tocolour blocks and matchcarefully. Always record For enhanced convenienceand standardisation, use aCLINITEK analyser to read thereagent strip and print :Layout 1 22/04/2009 09:41 Page 476 Reagentsglucose oxidase;peroxidase; potassiumiodide; buffer; PrinciplesThe test is based on adouble sequentialenzyme reactionutilising glucoseoxidase andperoxidase with apotassium iodideChromagen. Coloursrange from green tobrownSensitivity /SpecificityThe test is specific forglucose; no substanceexcreted in Urine otherthan glucose is knownto give a positiveresult.

7 Approximately of glucose isdetectable. The test ismore sensitive thanthe copper reductiontest, CLINITEST, whichwill detect (1/4%) glucoseas a , 4-dichloroanilinediazonium salt;buffer; PrinciplesThis test is based onthe coupling ofbilirubin withdiazoniumdichloroaniline in astrongly acidmedium. The colourranges throughvarious shades of / SpecificityTest has sensitivity of7 to 14 nitroprusside;buffer Chemical PrinciplesThis test is based onthe development of apink or marooncolour by the reactionof acetoacetic acidwith / SpecificityThe test reacts withacetoacetic acid inurine, but does notreact with acetone orbeta-hydroxybutyricacid. The test detectsas little as mmol/Lacetoacetic Principles Reagent Strip TestsReagentsbromthymol blue; poly (methyl vinylether/maleicanhydride); PrinciplesThis test is based onthe pKa change ofcertain pre-treatedpolyelectrolytes inrelation to ionicconcentration. In thepresence of anindicator, coloursrange from deepblue-green throughgreen and yellow-green in urines ofincreasing / SpecificityThe test determinesthe specific gravity ofurines in the to Ingeneral, the resultcorrelates with refractiveindex values.

8 Forincreased accuracyadd toreadings obtainedfrom urines with pHvalues equal to orgreater than ; 3,3, , tetramethylbenizidine; buffer; PrinciplesThis test is based onthe peroxidase-like-activity ofhaemoglobin, whichcatalyses the reactionof the reagent withthe chromogen. Theresulting colourranges from orangethrough green todark / SpecificityThe test is capable ofdetecting 150 to 620 g/L freehaemoglobin or 5 to20 intact red bloodcells per microlitre inurines with an The test is lesssensitive in urineswith a high andis more sensitive tofree haemoglobinthan intact red bloodcells. The appearanceof green spots on thereacted reagent padindicates thepresence of intacterythrocytes in ; buffer; PrinciplesThe test is based onthe protein-error-of-indicators pKa of someindicators is changedwhen they bind toprotein, changingcolour when proteinis added at a constantbuffered pH. Colourranges from yellowfor negative through yellow-green, green togreen-blue for positive / SpecificityQuantitative test,with trace resultindicating albuminconcentration ofbetween g/L.

9 Test is lesssensitive to globulin,Bence-Jones proteinand muco-protein,so a negative resultdoes not rule out thepresence of acid; 1, 2, 3, 4-tetra-hydrobenzo (h)-quinolin, 3-ol;buffer; PrinciplesThis test is based onthe conversion ofnitrate (derived fromdietary metabolites)to nitrite by theaction of certainspecies of bacteria inthe Urine . Any degreeof pink colour isconsidered positive. Sensitivity / SpecificityThe test is specific fornitrite, with asensitivity of 13 to22 mol/L nitrite inurines of normalspecific pyrroleamino acid ester;diazonium salt; buffer; PrinciplesThis test is based onthe principle thatesterases found ingranulocyticleucocytes catalysethe hydrolysis of aderivatised pyrroleamino acid ester toliberate 3-hydroxy-5-phenyl pyrrole. Thispyrrole then reactswith a diazoniumsalt to produce apurple / SpecificityThis test provides asemi-quantitativeresult for thepresence ofleucocytes, trace indicatingapproximately 5 to15 cells/ L,+ + + indicatingapproximately 500cells/ L.

10 The test forleucocytes is aspecific enzymaticreaction which isable to detect lysedcells in addition toundamaged cells. Inclinical studiesinvolving over 1000specimens, thesensitivity whencompared with thechamber count ofnumbers of 10 andmore cells/ red:bromthymol PrinciplesThe test is based onthe double indicatorprinciple, which givesa broad range ofcolours covering thepH range 5 to change fromorange throughyellow and green / SpecificityThe test providesquantitativedifferentiation ofurine pH in the range5 to Readings arenot affected byurinary buffervariations, but the pHmay be changed bycertain ; PrinciplesThe test is based onthe Ehrlich reaction,in which para-dimethylaminobenzaldehydereacts withurobilinogen in astrongly acid mediumto produce a brown-orange / SpecificityQuantitative test thatdetects urobilinogenconcentrations as lowas 3 mol/L in ofurobilinogen cannotbe determined by GravityBloodProteinNitriteLeucocytespHUr obilinogenClinical Significance of Test ResultsGlucoseBilirubinKetonesSpecific GravityBloodProteinNitriteLeucocytespHUr obilinogenSignificance of Positive ResultsGlucose is found inurine when itsconcentration inplasma exceeds therenal Causes of Positive ResultsIn patients withraised blood glucoseconcentration: Diabetes mellitus Glucose infusionIn patients withoutraised blood glucoseconcentration: Pregnancy Renal of Positive ResultsBilirubin in urineindicates an excessof conjugatedbilirubin in Causes of Positive ResultsLiver cell injury, as inviral or drug-inducedhepatitis.