Health Careers IHealth Careers I

Anatomy, Physiology and DiseaseAnatomy, Physiology and DiseaseChapter 5Chapter 5

Basic Diagnostic Tests:Basic Diagnostic Tests:What Do The Tests Tell Us?What Do The Tests Tell Us?

IntroductionIntroduction

Diagnostic testsDiagnostic tests help to provide a more accurate help to provide a more accurate view of patient’s overall condition and disease view of patient’s overall condition and disease state including state including diagnosisdiagnosis, , progressionprogression, or , or improvement.improvement.

Medical diagnosticsMedical diagnostics are like advanced are like advanced diagnostics for your car; tests can be used to diagnostics for your car; tests can be used to verify the verify the obviousobvious or to discover where or to discover where signssigns & & symptomssymptoms are pointing. are pointing.

Important things to keep in mind when Important things to keep in mind when interpreting test resultsinterpreting test results

Normal valuesNormal values for specific tests vary slightly from for specific tests vary slightly from lab to lablab to lab

Even perfectly healthy peopleEven perfectly healthy people will sometimes will sometimes have abnormalities on diagnostic testshave abnormalities on diagnostic tests

Test results must be interpreted in contextTest results must be interpreted in context of of patient’s overall medical history and physical patient’s overall medical history and physical exam; exam; not every abnormal test is significantnot every abnormal test is significant!!!!!!

Blood TestingBlood Testing

Composition of bloodComposition of blood Partly composed of liquid, partly cellsPartly composed of liquid, partly cells Liquid portion called plasmaLiquid portion called plasma Composed of about Composed of about 90% 90% waterwater

Several types of blood cellsSeveral types of blood cells

ErythrocytesErythrocytes ( (Red Blood CellsRed Blood Cells) medium-sized ) medium-sized blood cell; Transports oxygen from lungs to body blood cell; Transports oxygen from lungs to body cellscells

LeukocytesLeukocytes ( (White Blood Cells) White Blood Cells) large-sized blood large-sized blood cell; protects body from infectioncell; protects body from infection

ThrombocytesThrombocytes ( (PlateletsPlatelets) small-sized blood cell; ) small-sized blood cell; helps blood clot after cut or similar injuryhelps blood clot after cut or similar injury

Erythrocytes Leukocytes Thrombocytes

Types of Types of Blood CellsBlood Cells

Obtaining blood sample for testingObtaining blood sample for testing

Venous stickVenous stick: bluish blood vessels visible : bluish blood vessels visible through skin.through skin.

Finger stickFinger stick: pin prick to finger (which samples : pin prick to finger (which samples capillary capillary blood); example: diabetics testing their blood); example: diabetics testing their own blood sugar.own blood sugar.

Arterial stickArterial stick: to assess : to assess oxygenationoxygenation of blood of blood

Blood TubesVenous Accucheck

Arterial

Accu Check Accu Check MachineMachinefor for Blood Sugar Blood Sugar LevelsLevels

Red Blood Cell DisordersRed Blood Cell Disorders

AnemiaAnemia: lower than normal amounts of RBCs; : lower than normal amounts of RBCs; possible causes: possible causes: hemorrhagehemorrhage, low RBC , low RBC productionproduction, or RBC , or RBC destruction.destruction.

PolycythemiaPolycythemia:: higher than normal amounts of higher than normal amounts of RBCs; possible cause: RBCs; possible cause: chronically low oxygenchronically low oxygen in in blood.blood.

Anemia Sickle Cell Polycythemia

White Blood Cell DisordersWhite Blood Cell Disorders

LeukopeniaLeukopenia: : lower lower than normal amounts of than normal amounts of WBCsWBCs

CausesCauses: Cancer, radiation & chemotherapy, : Cancer, radiation & chemotherapy, antipsychotic medicinesantipsychotic medicines

LeukocytosisLeukocytosis: : higherhigher than normal amounts of than normal amounts of WBCs; possible causes: infection or leukemiaWBCs; possible causes: infection or leukemia

CausesCauses: Massive infection: Massive infection

Platelet DisordersPlatelet Disorders

ThrombocytopeniaThrombocytopenia: lower than normal number of : lower than normal number of platelets.platelets.

CausesCauses:: Vitamin Vitamin B12 B12 or or Folic Acid Folic Acid deficiency deficiency LeukemiaLeukemia SepsisSepsis (massive blood infection) (massive blood infection) Dengue feverDengue fever

Typical Dengue

Rash

Severe The Culprit

Centrifuged BloodCentrifuged Blood

Blood in tube spunBlood in tube spun to to separate cellsseparate cells from plasma from plasma Formed elementsFormed elements: heavier cells : heavier cells forced to forced to

bottombottom of tube. of tube. Dissolved substancesDissolved substances: upper level, lighter in : upper level, lighter in

weight & color, is weight & color, is plasma plasma or or liquid portionliquid portion of of blood.blood.

Centrifuged BloodCentrifuged Blood

Blood TestingBlood Testing

IncludesIncludes RBC RBC (red blood cell count) or (CBC)(red blood cell count) or (CBC) HctHct (hematocrit) “ (hematocrit) “judging bloodjudging blood” the proportion ” the proportion

of of blood volume that is occupied by RBCs volume that is occupied by RBCs HgbHgb (hemoglobin) “ (hemoglobin) “proteinprotein” ” 97% 97% of dry of dry

content of the RBC…content of the RBC… WBCWBC (white blood cell count) (white blood cell count) DiffDiff (differential white blood cell count) (differential white blood cell count) PlateletPlatelet count count

Red Blood Cell Count(RBCs)Red Blood Cell Count(RBCs)

Quantity of RBCsQuantity of RBCs in 1 cubic mm in 1 cubic mm

Normal valuesNormal values: men: 4.6-6.2; women: 4.2-5.4: men: 4.6-6.2; women: 4.2-5.4

Decreased numbers Caused byDecreased numbers Caused by

1.1. blood lossblood loss

2.2. dietary insufficiency (iron, folic acid, certain dietary insufficiency (iron, folic acid, certain vitamins)vitamins)

3.3. decreased RBC Productiondecreased RBC Production

4.4. increased RBC destructionincreased RBC destruction

Red Blood Cell CountRed Blood Cell Count

Polycythemia: Polycythemia: too many RBCs….too many RBCs….

1.1. dehydration, diarrhea (severe)dehydration, diarrhea (severe)

2.2. high altitudehigh altitude

3.3. over production by bone marrowover production by bone marrow

4.4. SmokingSmoking

5.5. Adrenal gland illnessesAdrenal gland illnesses

Hematocrit (Hematocrit (HctHct))

Determines what percentDetermines what percent of the blood is composed of of the blood is composed of RBCs.RBCs. Normal valuesNormal values: : menmen: 40-54%; : 40-54%; womenwomen: 38-47%: 38-47% Higher than normal HctHigher than normal Hct 1. dehydration 2. shock1. dehydration 2. shock Lower than normal HctLower than normal Hct 1. 1. anemia anemia 2. 2. hemorrhagehemorrhage, 3. , 3. hemolytic reactionshemolytic reactions

(blood cell destruction – such as what occurs when (blood cell destruction – such as what occurs when incompatible blood is transfused)incompatible blood is transfused)

Hemolytic ReactionHemolytic Reaction

Hemoglobin(Hemoglobin(HgbHgb))

Measures protein in RBCsMeasures protein in RBCs that carries oxygen that carries oxygen Normal valuesNormal values: : menmen: 13.5 – 17.5 g/dl; : 13.5 – 17.5 g/dl; womenwomen: 12-: 12-

16 g/dl; 16 g/dl; newbornsnewborns: 14-16 g/dl: 14-16 g/dl Decreased hemoglobinDecreased hemoglobin: anemia, excessive fluid : anemia, excessive fluid

intake, hemorrhage, pregnancy intake, hemorrhage, pregnancy Increased hemoglobinIncreased hemoglobin: : COPD COPD (which may result (which may result

in chronically low blood oxygen), high altitude in chronically low blood oxygen), high altitude

White Blood Cell Count White Blood Cell Count ((WBCsWBCs))

Measures total number of white blood cells 103/mm3

Normal values: men: 4.5-11; women: 4.5-11 ((leukopenialeukopenia): Decreased WBCs diagnosed with ): Decreased WBCs diagnosed with

WBC < 4,000WBC < 4,000• May be caused byMay be caused by alcoholism, viral infections, alcoholism, viral infections,

any chronic infection where body is so “any chronic infection where body is so “worn worn outout” that it cannot continue to produce enough ” that it cannot continue to produce enough WBCsWBCs

• ““panic valuepanic value,” WBC<500 is requires “,” WBC<500 is requires “STATSTAT” ” attention.attention.

White Blood Cell Count White Blood Cell Count ((WBCsWBCs) con’t) con’t

((leukocytosisleukocytosis) ) Increased WBCsIncreased WBCs Diagnosed with WBC > 10,000Diagnosed with WBC > 10,000 Usually results from an increase in just one Usually results from an increase in just one

type of WBCtype of WBC May be caused byMay be caused by infection, infection,

malignancy/leukemia, steroid therapy, malignancy/leukemia, steroid therapy, hemorrhage, coma, stress (pain/excitement), hemorrhage, coma, stress (pain/excitement), menstruation.menstruation.

Differential white blood cell count Differential white blood cell count (Diff)(Diff)

Measures each different type of WBCMeasures each different type of WBC Types of WBCsTypes of WBCs

• NeutrophilsNeutrophils: combat bacterial infection, : combat bacterial infection, inflammation and stressinflammation and stress

• LymphocytesLymphocytes: fight viral infections: fight viral infections• EosinophilsEosinophils: respond to allergic conditions and : respond to allergic conditions and

parasitic invasionsparasitic invasions• MonocytesMonocytes: respond to severe and chronic : respond to severe and chronic

infectionsinfections• BasophilsBasophils: respond to inflammation & blood : respond to inflammation & blood

disordersdisorders

Platelet countPlatelet count

Determines number of platelets in bloodDetermines number of platelets in blood Normal valuesNormal values: 150,000-350,000 / mm: 150,000-350,000 / mm33

ThrombocytopeniaThrombocytopenia: : decreased plateletsdecreased platelets may be may be caused by blood transfusions, bone marrow caused by blood transfusions, bone marrow lesions, cancer chemotherapy, lesions, cancer chemotherapy, infections/pneumonia, toxic drug effectsinfections/pneumonia, toxic drug effects

ThrombocytosisThrombocytosis: : Increased plateletsIncreased platelets may be may be caused by splenectomy, heart disease, high caused by splenectomy, heart disease, high altitude living, iron deficiency, trauma, altitude living, iron deficiency, trauma, tuberculosis, cancertuberculosis, cancer

PT (PT (Prothrombin Time, ProTimeProthrombin Time, ProTime))

Timed testTimed test that measures blood’s ability to clot that measures blood’s ability to clot through use of the through use of the proteinprotein prothrombinprothrombin produced produced by the liver.by the liver.

Prothrombin Prothrombin converts converts to to thrombinthrombin Body needs Body needs Vit K Vit K to produce to produce prothrombinprothrombin Normal values: 10-14 secNormal values: 10-14 sec

PT (PT (Prothrombin Time, ProTimeProthrombin Time, ProTime) con’t) con’t

Increased ProTimeIncreased ProTime: suggests blood will not clot : suggests blood will not clot as quickly as normal; ex: patients on as quickly as normal; ex: patients on anti-anti-coagulantcoagulant therapy such as therapy such as CoumadinCoumadin

Decreased ProTimeDecreased ProTime: suggests : suggests increaseincrease in in blood’s ability toblood’s ability to clot clot; may result from excessive ; may result from excessive consumption of green, leafy vegetables (which consumption of green, leafy vegetables (which alters alters vitamin K vitamin K levels, and therefore alters levels, and therefore alters prothrombin levels or too much prothrombin levels or too much Vit KVit K..

Decreased ProTime Decreased ProTime may result in may result in blood clotsblood clots

PTT (PTT (Partial Thromboplastin TimePartial Thromboplastin Time) )

Timed testTimed test that measures blood’s that measures blood’s ability to clotability to clot through intrinsic through intrinsic thromboplastinthromboplastin system system

Used to monitor administration of Used to monitor administration of HeparinHeparin Normal valuesNormal values: 30-45 sec: 30-45 sec Increased PTTIncreased PTT: suggests blood will not clot as : suggests blood will not clot as

quickly as normal; ex: pts on quickly as normal; ex: pts on anti-coagulant anti-coagulant therapytherapy such as such as heparinheparin..

Blood Testing ResultsBlood Testing ResultsDon’t copy this!!! I will discuss this slide.Don’t copy this!!! I will discuss this slide.

BUN (BUN (Blood Urea NitrogenBlood Urea Nitrogen))

Measurement of kidney’s ability to eliminate ureaMeasurement of kidney’s ability to eliminate urea ((waste productwaste product) from blood) from blood

Normal valuesNormal values: 7-18ml/dl or 2.5-6.3mmol/L: 7-18ml/dl or 2.5-6.3mmol/L

BUN (BUN (Blood Urea NitrogenBlood Urea Nitrogen) (cont’d)) (cont’d)

Increased BUN Increased BUN May be caused by renal function impairment, May be caused by renal function impairment,

non-renal causes (acute MI, chronic gout, non-renal causes (acute MI, chronic gout, diabetes, excessive protein consumptiondiabetes, excessive protein consumption

Signs and symptomsSigns and symptoms of increased BUN: of increased BUN: confusion, convulsions, Hypertensionconfusion, convulsions, Hypertension

Decreased BUNDecreased BUN

May be caused byMay be caused by

1.1. low protein diet/malnutrition,low protein diet/malnutrition,

2.2. fluid overload, fluid overload,

3.3. liver failure, liver failure,

4.4. nephrotic syndromenephrotic syndrome S/S of edemaS/S of edema

BUN Testing ResultsBUN Testing Results

ElectrolytesElectrolytes

Crucial for proper cellular function Crucial for proper cellular function throughout throughout body; body must maintain normal concentrations body; body must maintain normal concentrations of various electrolytes of various electrolytes

Amount of water in body Amount of water in body (too much or too little) (too much or too little) can affect electrolyte concentrationscan affect electrolyte concentrations

Electrolyte Testing ResultsElectrolyte Testing Results

Calcium (Ca++)Calcium (Ca++)

Normal valuesNormal values: : 4.5-5.4 mEq/L4.5-5.4 mEq/L HypercalcimiaHypercalcimia: Increased Calcium: Increased Calcium Caused byCaused by hyperparathyroidism, malignant hyperparathyroidism, malignant

tumors, diuretic therapy, excessive calcium tumors, diuretic therapy, excessive calcium consumption (milk or antacids), vitamin D consumption (milk or antacids), vitamin D intoxication.intoxication.

S/SS/S: anorexia, constipation, lethargy & : anorexia, constipation, lethargy & weakness, hyporeflexia, mental deterioration, weakness, hyporeflexia, mental deterioration, kidney stoneskidney stones

Calcium (Ca++) con’tCalcium (Ca++) con’t

HypocalcimiaHypocalcimia: Decreased calcium: Decreased calcium Caused byCaused by hypoparathyroidism, vitamin D hypoparathyroidism, vitamin D

deficiency, diuretic therapy, pregnancydeficiency, diuretic therapy, pregnancy S/SS/S: muscle cramping, paresthesia, mental : muscle cramping, paresthesia, mental

disturbances, convulsionsdisturbances, convulsions

Chloride (ClChloride (Cl--))

Normal valuesNormal values: 95-103 mEq/L: 95-103 mEq/L Decreased ChlorideDecreased Chloride: caused by excessive : caused by excessive

vomiting, dehydration, burns.vomiting, dehydration, burns. S/SS/S: depressed breathing, muscle : depressed breathing, muscle

hypertonicity/hypertonicity/tetanustetanus

Potassium (KPotassium (K++))

Normal ValuesNormal Values: : 3.8-5.0 mEq/L3.8-5.0 mEq/L Hyperkalemia-High potassiumHyperkalemia-High potassium: caused by : caused by

muscle tissue damage, renal failure muscle tissue damage, renal failure S/SS/S: diarrhea/nausea, : diarrhea/nausea, ventricular fibrillation ventricular fibrillation

(heart dysrrhythmias), irritability, weakness(heart dysrrhythmias), irritability, weakness. . confusionconfusion..

Potassium (KPotassium (K++))

Hypokalemia: Hypokalemia: Decreased PotassiumDecreased Potassium Caused byCaused by diuretic therapy, diarrhea, endocrine diuretic therapy, diarrhea, endocrine

disorder, chronic stressdisorder, chronic stress S/SS/S: : cardiac arrhythmiascardiac arrhythmias, hypotension, muscle , hypotension, muscle

weakness, malaise weakness, malaise

Dangerous Cardiac Arrest

Sodium (NaSodium (Na++))

Normal valuesNormal values: 136-142 mEq/L: 136-142 mEq/L HypernatremiaHypernatremia: Increased sodium: : Increased sodium: Caused byCaused by dehydration dehydration S/SS/S: dry mucous membranes & tongue, intense : dry mucous membranes & tongue, intense

thirst, flushed skinthirst, flushed skin

Sodium (NaSodium (Na++) con’t) con’t

HyponatremiaHyponatremia: : Low Sodium LevelLow Sodium Level Etiology:Etiology: excessive water intake, loss of GI excessive water intake, loss of GI

secretions, excessive sweating, burnssecretions, excessive sweating, burns S/SS/S: abdominal cramps, muscle twitching, : abdominal cramps, muscle twitching,

confusion, seizures, vasomotor collapseconfusion, seizures, vasomotor collapse

EnzymesEnzymes

Complex proteinsComplex proteins that facilitate chemical that facilitate chemical changeschanges

Normally foundNormally found inside body cells inside body cells May be released into bloodstreamMay be released into bloodstream following cell following cell

injury or death; example: injury or death; example: cardiac enzymescardiac enzymes are are released into bloodstream when cardiac tissue released into bloodstream when cardiac tissue dies during dies during heart attackheart attack

Urine TestingUrine Testing

Body makesBody makes 1-1.5 liters of urine every day 1-1.5 liters of urine every day Kidneys produce urine in order toKidneys produce urine in order to: :

• Excrete wasteExcrete waste• Regulate concentration of various Regulate concentration of various

substances in bloodsubstances in blood Morning urineMorning urine is best for testing as it is the most is best for testing as it is the most

concentrated.concentrated.

Urine Testing (cont’d)Urine Testing (cont’d)

DipsticksDipsticks: have several different areas : have several different areas impregnated with different reactive chemicalsimpregnated with different reactive chemicals ProcedureProcedure: dipstick is dipped into urine and : dipstick is dipped into urine and

observed for color changes observed for color changes Urine properties measured by dipstickUrine properties measured by dipstick: pH, : pH,

bilirubin, ketones, glucose, leukocyte bilirubin, ketones, glucose, leukocyte esterase, protein, hemoglobin, nitrite, esterase, protein, hemoglobin, nitrite, urobilinogenurobilinogen

Urine TestingUrine Testing

Specific gravitySpecific gravity

Measurement ofMeasurement of: : 1.1. Kidney’s ability to concentrate urineKidney’s ability to concentrate urine

2.2. Hydration of a patientHydration of a patient

3.3. Amount of solids mixed in urine Amount of solids mixed in urine Normal valuesNormal values: : 1.010-1.0251.010-1.025

Concentrated urineConcentrated urine = 1.025-1.030+; suggests = 1.025-1.030+; suggests dehydrationdehydration

Diluted urineDiluted urine = 1.001-1.010; suggests = 1.001-1.010; suggests overhydrationoverhydration or or diureticdiuretic use use

Factors that can interfere with urine test resultsFactors that can interfere with urine test results

Use of diureticsUse of diuretics HypercalcemiaHypercalcemia Potassium deficiencyPotassium deficiency Liver, Bone & diseasesLiver, Bone & diseases

Urine ColorUrine Color

Normal valuesNormal values: straw-amber color: straw-amber color Abnormal urine colors and their significanceAbnormal urine colors and their significance

BlackBlack: Lysol poisoning; alkaptonuria: Lysol poisoning; alkaptonuria BrownBrown: Addison’s disease, drugs, melanotic tumor, : Addison’s disease, drugs, melanotic tumor,

bilirubin, rhubarb ingestionbilirubin, rhubarb ingestion Clear/nearly clearClear/nearly clear: ETOH or other diuretic substances, : ETOH or other diuretic substances,

large fluid intake, diabetes insipidus, chronic interstitial large fluid intake, diabetes insipidus, chronic interstitial nephritis, untreated diabetes mellitusnephritis, untreated diabetes mellitus

OrangeOrange: concentrated urine, decreased fluid intake, : concentrated urine, decreased fluid intake, excessive sweating, drugsexcessive sweating, drugs

RedRed: (: (hematuriahematuria) blood/hemoglobin, beets, drugs) blood/hemoglobin, beets, drugs

Urine….Urine….

Urine odorUrine odor

Normal urineNormal urine has distinct, but non-offensive has distinct, but non-offensive aromaaroma

Unusual odorsUnusual odors can suggest specific problems can suggest specific problems• Ammonia scentAmmonia scent: stale urine with bacterial activity: stale urine with bacterial activity• General sweet smellGeneral sweet smell: diabetic : diabetic ketosisketosis• Maple syrup scentMaple syrup scent: particular metabolic disorder: particular metabolic disorder

Urine pH (Urine pH (acidityacidity))

Controlled by kidneysControlled by kidneys to maintain homeostatic pH in body to maintain homeostatic pH in body Normal valuesNormal values: pH of 4.6-8 (with : pH of 4.6-8 (with average pH of 6average pH of 6)) Excessively acidic urineExcessively acidic urine may be due to may be due to respiratory acidosis respiratory acidosis

(retention of CO(retention of CO22 in lungs causes extra acid in blood, which in lungs causes extra acid in blood, which

kidneys try to eliminate), diarrhea/dehydration, high protein kidneys try to eliminate), diarrhea/dehydration, high protein diets, starvationdiets, starvation

Excessively alkaline urineExcessively alkaline urine may be due to may be due to hyperventilation hyperventilation (body blows off too much CO(body blows off too much CO22 causing deficient acid in causing deficient acid in

blood; kidneys try to correct blood pH by eliminating less blood; kidneys try to correct blood pH by eliminating less acid into urine), acid into urine), chronic renal failurechronic renal failure, , renal tubular acidosisrenal tubular acidosis, , urinary tract infectionurinary tract infection (UTI), (UTI), salicylatesalicylate ( (aspirin) aspirin) intoxicationintoxication

Urine turbidityUrine turbidity

Measure ofMeasure of how “ how “cloudycloudy” urine appears” urine appears Normal valuesNormal values: clear to slightly hazy: clear to slightly hazy Cloudy urine may be caused byCloudy urine may be caused by

• Bacteria Bacteria (infection)(infection)• PusPus (lots of WBCs) (lots of WBCs)• Red Red blood cells (blood cells (hematuriahematuria))• Ingestion of certain foods (especially greasy/fatty Ingestion of certain foods (especially greasy/fatty

foods)foods)• Vaginal contamination Vaginal contamination (common occurrence (common occurrence • when women give urine samples)when women give urine samples)

Urine SugarUrine Sugar

GlycosuriaGlycosuria or or GlucosuriaGlucosuria

Caused byCaused by::

1. un-treated or inadequately treated DM1. un-treated or inadequately treated DM

2. emotional stress2. emotional stress

3. early Renal Failure3. early Renal Failure

Urine protein (Urine protein (proteinuriaproteinuria))

Normal ValuesNormal Values: 50-80mg /24 hours: 50-80mg /24 hours Causes of ProteinuriaCauses of Proteinuria: :

• activitiesactivities: bathing or swimming in : bathing or swimming in cold watercold water, , eating large amounts of eating large amounts of proteinprotein, violent/intense , violent/intense exerciseexercise, severe emotional , severe emotional stressstress

• Renal diseaseRenal disease: kidney stones, nephritis, : kidney stones, nephritis, nephrosis, polycystic kidney, tuberculosis or nephrosis, polycystic kidney, tuberculosis or cancer of the kidneycancer of the kidney

Urine ketone bodies (Urine ketone bodies (acetoneacetone))

Ketones released as result ofKetones released as result of metabolism of fatty metabolism of fatty acids; takes place when body runs out of acids; takes place when body runs out of carbohydrates to burncarbohydrates to burn

Normal valuesNormal values: negative: negative Causes of KetonuriaCauses of Ketonuria: DM, anorexia/starvation/ : DM, anorexia/starvation/

fasting, diarrhea/prolonged vomiting, fever, fasting, diarrhea/prolonged vomiting, fever, drugs (i.e. insulin)drugs (i.e. insulin)

Urine Bacteria Urine Bacteria

Normal valuesNormal values: negative : negative Presence of bacteria in urine can suggest Presence of bacteria in urine can suggest

urinary tract infection (urinary tract infection (UTIUTI))

Fecal MatterFecal Matter Normal stoolNormal stool: 100-200 g/day, dark brown: 100-200 g/day, dark brown Color AbnormalitiesColor Abnormalities::

• Yellow/yellow-Yellow/yellow-greengreen: breast fed infant, bowel : breast fed infant, bowel sterilization due to antibiotics, severe diarrheasterilization due to antibiotics, severe diarrhea

• GreenGreen: severe diarrhea, antibiotic therapy, : severe diarrhea, antibiotic therapy, ingestion of chlorophyll-rich vegetablesingestion of chlorophyll-rich vegetables

• Tan/clayTan/clay: common bile duct blockage, pancreatic : common bile duct blockage, pancreatic insufficiency, excessive fat intakeinsufficiency, excessive fat intake

• Black: Black: upper GI bleeding, ingestion of iron, high upper GI bleeding, ingestion of iron, high meat diet, ingestion of charcoal or bismuthmeat diet, ingestion of charcoal or bismuth

• RedRed: bleeding from lower GI tract; if red streaking : bleeding from lower GI tract; if red streaking on outer surface of stool, consider hemorrhoids or on outer surface of stool, consider hemorrhoids or anal pathology; if blood mixed through stool, anal pathology; if blood mixed through stool, consider problem higher up GI tractconsider problem higher up GI tract

Blood in stoolBlood in stool

CausesCauses: gastritis, gastric ulcers, diverticulitis, : gastritis, gastric ulcers, diverticulitis, ulcerative colitis, colon or gastric cancer, ulcerative colitis, colon or gastric cancer, trauma.trauma.

Conditions that cause false-positiveConditions that cause false-positive occult blood occult blood tests: ingestion of tests: ingestion of red meat,red meat, large amounts of large amounts of inorganic ironinorganic iron, and large doses of , and large doses of vitamin Cvitamin C

Pathology Conncection:Pathology Conncection:Colon PolypsColon Polyps

Cerebral Spinal Fluid (Cerebral Spinal Fluid (CSFCSF))

Clear and colorless fluidClear and colorless fluid found in ventricles of found in ventricles of the brain and central canal of the spinal cordthe brain and central canal of the spinal cord

FunctionsFunctions: acts as a : acts as a shock absorbershock absorber, helps , helps regulate regulate intracranial pressureintracranial pressure, cranial glucose , cranial glucose levels, leading to hunger sensations & eating levels, leading to hunger sensations & eating behaviors.behaviors.

CSF AnalysisCSF Analysis

Normal valuesNormal values Normal daily production Normal daily production = 500ml= 500ml Normal circulation Normal circulation around brain and spinal around brain and spinal

cord = 150-200mlcord = 150-200ml Normal color Normal color = clear, colorless= clear, colorless Normal cell count Normal cell count = 0-5/microliters= 0-5/microliters

Adult Spinal TapAdult Spinal Tap

CSF AbnormalitiesCSF Abnormalities

Abnormalities due toAbnormalities due to:: HemorrhageHemorrhage Micro-organismsMicro-organisms TumorsTumors Infections (like Infections (like meningitismeningitis)) TraumaTrauma

Culture and Sensitivity Culture and Sensitivity (C&S) Testing(C&S) Testing

PurposePurpose: to identify pathogen causing infection : to identify pathogen causing infection ((cultureculture) and which drug will most effectively kill ) and which drug will most effectively kill pathogen (pathogen (sensitivitysensitivity))

Important considerationsImportant considerations Culture may grow Culture may grow normal floranormal flora as well as as well as

pathogenspathogens C&S results may be C&S results may be alteredaltered if patient is already if patient is already

on some kind of on some kind of antibioticantibiotic