Dr. Iman M. Fawzy; MD. PhD.Mansoura, Egypt

BASIC LABORATORY INVESTIGATIONS

Urinalysis

COMPONENTS OF THE URINE DIPSTICK

• Color:pale yellow to amber• Specific gravity: 1.015–1.025• pH: 4.5–8.0• Protein: negative• Glucose: negative• Ketone: negative• Bilirubin: negative• Urobilinogen: 0.2–1.0• Blood: negative• Nitrite: negative• Leukocytes (esterase): negative

COMPONENTS OF THE URINE DIPSTICK

Microscopic Examination of Urine Sediment

Increased WBCs are seen in Urinary tract disease (eg, cystitis, prostatitis)Chronic pyelonephritisTuberculosisViral infectionInterstitial nephritisGlomerulonephritis

WBC casts Pyelonephritis (most common cause)Acute glomerulonephritisInterstitial nephritisLupus nephritis

URINE WHITE BLOOD CELLSNormal Values: WBCs: 0–4/hpf

Microscopic Examination of Urine Sediment

Increased numbers of RBCs occur in • Contamination during Menstrual cycle • Glomeulo and Pyelonephritis• Renal stones• Cystitis (acute or chronic)• Prostatitis• Genitourinary tract malignancies• Bleeding disorders• Trauma• Anticoagulant therapy overdose

RBC casts in• Glomerulonephritis (acute and chronic)• Renal infarction• Severe pyelonephritis• Congestive heart failure• Renal vein thrombosis

URINE RED BLOOD CELLSNormal Values: RBCs: 0–3/HPF

Microscopic Examination of Urine SedimentGRANULAR CASTSAcute tubular necrosis Advanced glomerulonephritis Pyelonephritis Malignant nephrosclerosisFever (dehydration)

Hyaline castsGlomerulonephritis, pyelonephritis Malignant hypertension Chronic renal disease Diabetic nephropathyFever (dehydration) Emotional stress Strenuous exercise

WAXY CASTSChronic renal disease Nephrotic syndrome Localized nephron obstruction

Fatty castslipiduria e.g. nephrotic syndrome

Urinary sediment crystals

Acidic urine• Uric acid crystal• Amorphous urates• Cholesterol crystals

Alkaline urine• Triple phosphate

crystals• Calcium phosphate• Amorphous phosphates

ACID, NEUTRAL, OR SLIGHTLY ALKALINE URINECalcium oxalate

URINE COMPOSITION URINALYSIS: FINDINGS IN COMMON DISEASE STATES.

Disease Protein RBC WBC Casts Other Microscopic Findings

Normal 0 0 or Occ 0 or Occ 0 or Occ Hyaline casts

Fever Trace or 1+ 0 Occ 0 or Occ Granular, Hyaline casts

Eclampsia 3+-4+ 0 or 1+ 0 3+, 4+ Hyaline castsDM v 0 0 0 or 1+ Glucose, ketones

AGM 2+-4+ 1+-4+ v 2+-4+ Blood; RBC, cellular, granular, and hyaline casts

Nephrotic syndrome 4+ 0 4+ Granular, waxy, hyaline,

and fatty castsChronic renal failure 1+-2+ Occ or

1+ 0 1+-3+ Granular, hyaline, and broad casts

Pyelonephritis 1+-2+ 0 or 1+ 4+ 0 or 1+WBC casts and hyaline casts; many pus cells; bacteria

Clinical Microbiology

Organisms may found in UrineBACTERIA

Gram positive Gram negativeStaphylococcus Escherichia colisaprophyticus Proteus speciesHaemolytic streptococci Pseudomonas aeruginosa

Klebsiella strains

Mycobacterium tuberculosisLeptospira interrogansChlamydiaMycoplasma

CandidaPARASITES

Schistosoma haematobium,Trichomonas vaginalisEnterobius vermicularisWuchereria bancrofti Onchocerca volvulus.

Organisms may found in CSFBACTERIA

Gram positive Gram negativeStreptococcus pneumoniae Neisseria meningitidis

Streptococcus agalactiae (Group B) Haemophilus influenzaeListeria monocytogenes Escherichia coli

Pseudomonas aeruginosa

Proteus specie Mycobacterium tuberculosisTreponema pallidum.

Organisms may found in CSFVIRUSES

CoxsackievirusesEchovirusarboviruses.herpes simplex 2 virusvaricella zoster virus

FUNGICryptococcus neoformans (mainly in AIDS patients)Aspergillus species.

PARASITESTrypanosoma species and Naegleria fowleriToxoplasma gondii (mainly in AIDS patients).

Bacterial meningitis

Glucose (mg/dL): Normal to ↓↓<40 mg/dL.

Protein (mg/dL) ↑↑ > 250 mg/dL.

WBCs (cells/µL) >500 (usually > 1000). Early: May be < 100.

Cell differential: Predominance of Neutrophils (PMNs)

Culture: PositiveOpening Pressure ↑

Fungal meningitisGlucose (mg/dL): <40 mg/dL (Low)

Protein (mg/dL) (moderate to ↑↑) 25 -500 mg/dL

WBCs (cells/µL) Variable (10 -1000 cells/µL) <500cells/µL.

Cell differential: Predominance of Lymphocytes

Culture: Positive (fungal)Opening Pressure Variable

TB meningitis

Glucose (mg/dL): <40 mg/dL (Low)

Protein (mg/dL) (moderate to ↑↑50 -500 mg/dL

WBCs (cells/µL) Variable (10 -1000 cells/µL) <500cells/µL.

Cell differential: Predominance of Lymphocytes

Culture: Positive for AFB

Opening Pressure Variable

Viral meningitis

Glucose (mg/dL): Normal (> 40 mg/dL.)

Protein (mg/dL) <100 mg/dL (moderate ↑)

WBCs (cells/µL) < 100 cells/µL.

Cell differential: Early: neutrophils. Late: lymphocytes.

Culture: Negative

Opening Pressure Usually normal

Blood CulturesBACTERIA

Gram positive Gram negativeStaphylococcus aureus Salmonella Typhi

Viridans streptococci Other Salmonella serovarsStreptococcus pneumoniae Brucella speciesStreptococcus pyogenes Haemophilus influenzaeEnterococcus faecalis Pseudomonas aeruginosaClostridium perfringens Klebsiella strainsAnaerobic streptococci Escherichia coli

Proteus speciesBacteroides fragilisNeisseria meningitidisYersinia pestis

Mycobacterium tuberculosis (HIV-associated tuberculosis), Leptospira species, Borrelia species,rickettsiae, Bartonella bacilliformis.

FUNGICandidaalbicansandother yeasts, e.g. Cryptococcus neoformans, and occasionally Histoplasma capsulatum

and other fungi that cause systemic mycoses.

Throat culture

BACTERIA

Gram positive Gram negativeStreptococcus pyogenes Vincent’s organismsCorynebacterium diphtheriaeCorynebacterium ulcerans

VIRUSESRespiratory virusesenteroviruses and herpes simplex virus type 1

FUNGICandida albicans and other yeasts.

pus, ulcer material and skin culture

BACTERIAGram positive Gram negative

Staphylococcus aureus Pseudonomas aeruginosaStreptococcus pyogenes Proteus speciesEnterococcus species Escherichia coliAnaerobic streptococci Bacteriodes speciesOther streptococci Klebsiella speciesClostridium perfringens Pasteurella speciesand other clostridiaActinomycetesActinomyces israeliAlso Mycobacterium tuberculosis

FUNGIHistoplasma c. duboisiiCandida albicansFungi that cause mycetoma

PARASITESEntamoeba histolytica

Effusions cultureSYNOVIAL FLUID

Gram positive Gram negativeStaphylococcus aureus Neisseria gonorrhoeaeStreptococcus pyogenes Neisseria meningitidisStreptococcus pneumoniae Haemophilus influenzaeAnaerobic streptococci Brucella species

Actinomycetes Salmonella serovarsEscherichia coliPseudomonas aeruginosaProteus

Bacteroides

Mycobacterium tuberculosis

Effusions culture

PLEURAL AND PERICARDIAL FLUIDS

BacterialGram positive Gram negative

Staphylococcus aureus Haemophilus influenzaeStreptococcus pneumoniae BacteroidesStreptococcus pyogenes Pseudomonas aeruginosaActinomycetes Klebsiella strains

Other enterobacteria

Mycobacterium tuberculosis fungiViruses especially coxsackie B virus

Effusions culture

ASCITIC FLUIDGram positive Gram negative

Enterococcus species Escherichia coliStreptococcus pneumoniae Klebsiella strainsStaphylococcus aureus Other enterobacteriaStreptococcus pyogenes Pseudomonas aeruginosaStreptococcus agalactiae BacteroidesViridans streptococciClostridium perfringens

Mycobacterium tuberculosisCandida species

Urogenital cultureURETHRAL SWABS

Neisseria gonorrhoeaeChlamydia trachomatis (serovars D-K)UreaplasmaMycoplasmaTrichomonas vaginalis.

Urogenital cultureCERVICAL SWABSFrom non-puerperal women:

Neisseria gonorrhoeae, Chlamydia trachomatis (serovars D-K),Streptococcus pyogenes, herpes simplex virus.

From women with puerperal sepsis or septic abortion:Streptococcus pyogenes, other betahaemolytic streptococci,

Staphylococcus aureus, Enterococcus species, anaerobic cocci, Clostridium perfringens, Bacteroides, Proteus, Escherichia coli and other coliforms, Listeria monocytogenes.

Urogenital cultureVAGINAL SWABS

Trichomonas vaginalisCandida speciesGardnerella vaginalis anaerobes

Stool sampleBACTERIA

Gram positive Gram negativeClostridium perfringens Shigella speciesClostridium difficile Salmonella serovars Staphylococcus aureus Campylobacter species

Escherichia coli (toxin)Vibrio cholerae 01, 0139Other Vibrio speciesAeromonas species

Mycobacterium tuberculosis

VIRUSESRotaviruses, Adenoviruses, , Astrovirus, calcivirus

PARASITESEntamoeba histolytica, Giardia lamblia

Sputum BACTERIA

Gram positive Gram negativeStreptococcus pneumoniae Haemophilus influenzaeStaphylococcus aureus Klebsiella pneumoniaeStreptococcus pyogenes Pseudomonas aeruginosa

Proteus speciesYersina pestisMoraxella catarrhalis

Mycobacterium tuberculosisMycoplasma pneumoniaeLegionella pneumophila.

FUNGI AND ACTINOMYCETESPneumocystis jiroveci, Blastomyces dermatitidis, Histoplasma capsulatum, Aspergillus species,

Candida albicans, Cryptococcus neoformans, and Nocardia species.

PARASITESParagonimus species

Serology

Widal test

negative Widal

absence of infection by S typhi and para typhiFalse negative• the carrier state• early treatment• hidden organism in bone or

joints• Technical errors

positive Widal

Typhoid feverFalse positive in: • previous immunization with

Salmonella antigen.• cross-reaction with non-

typhoidal Salmonella.• infection with malaria, Brucella,

other Enterobacteriaceae, dysentry, pneumonia, dengue, immune diseases

• Technical errors

O antigen: 4 fold ↑ if repeatedOr O antigen >1:160, H> 1: 320 in endemic areas

Brucella antibody

negative

absence of infection by Brucella infection

False negative• B canis infection• Technical errors

positive

• Brucella infection (except B canis)

False positive in: • infections with Francisella

tularensis, Yersinia enterocolitica, salmonella, Rocky Mountain spotted fever; vaccinations for cholera

• Technical errors

Positive titer ≥1:80↑≥ 4-fold in serum specimens obtained >2 weeks apart.

C-reactive protein (CRP)Positive titre: >6 mg/dLPositive in: • InflammationFalse positive in: • High protein diet• Smoking• Aging• Pregnancy or contraceptive use• Metabolic syndrome (insulin resistance)• Diabetes• Elevated triglycerides• Cancer

Rheumatoid factor (RF)

Positive titre: >8 mg/dLPositive in: • Rheumatoid arthritis (75-90%), False positive in • Other auto immune diseases• Drugs: methyldopa, others.• 1-4% of normal individuals, acute immune responses (eg, viral

infections, including infectious mononucleosis and viral hepatitis), chronic bacterial infections (tuberculosis, leprosy, subacute infective endocarditis), and chronic active hepatitis

False negative:• 20% of Rheumatoid arthritis

Antistreptolysin O titer (ASO)

Positive titre: >200 IU/mL• Detects antibody to the antigen streptolysin O produced by

group A streptococci.Titer rises to a peak at 4-6 weeks and may remain elevated for 1 year.

Positive in: • Streptococcal infection (eg, upper airway infections,

scarlet fever)• post-streptococcal infection complication (eg,

glomerulonephritis and rheumatic fever). False positive in• Some bacterial infections.

Hepatitis A antibody (Anti-HAV)

Positive in: • IgM: Acute hepatitis A• IgG: convalescence from hepatitis AIgM antibody is detectable within a week after

symptoms develop and persists for 6 months.IgG appears 4 weeks later than IgM and persists

for years.

Hepatitis B surface antigen (HBsAg)In hepatitis B virus infection HBsAg is • detectable 2-5 weeks before

onset of symptoms• peaks at the time of onset of

clinical illness.• persists for 1-5 months• Declining with resolution of

clinical symptoms.Positive in: • Acute hepatitis B • chronic hepatitis B (persistence

of HBsAg for >6 months, positive HBcAb [total])

• HBsAg positive carriers..

HBV markers

Hepatitis B markers

Hepatitis C antibody (HCV-Ab)

Detects antibody to HCVPositive in:

HCV infection

False positive:autoimmune liver disease Hypergammaglobulinemia

False negative:immunosuppressed patientslong-term hemodialysis.

HCVANTI-HCV HCV RNA (PCR) INTERPRETATION

Negative Negative No infection

Positive Positive HCV present (acute or chronic infection)

Negative Positive•Chronic infection in immunosuppressed patient•Early infection

Positive Negative•Resolved infection•Treated infection•False-positive anti-HCV test

HIV antibody

• HIV antibody test is considered positive only when confirmed by a Western blot analysis or immunofluorescent antibody test (IFA).

Positive in: • HIV infection

Toxoplasma antibodys

Toxo IgGToxo IgMPositive in: • IgM: Acute or congenital toxoplasmosis• IgG: previous toxoplasma exposurefalse-positive • SLE, HIV infection, positive rheumatoid factor,

positive ANA.

AUTOANTIBODIES: ASSOCIATIONS WITH CONNECTIVE TISSUE DISEASES

Disease Test Sensitivity, Specificity Other Disease

CREST Anti-centromere antibody CREST (70-90%, high) Scleroderma (10-15%), Raynaud disease (10-30%).

SLE

ANA SLE (>95%, low) RA (30-50%), scleroderma (60%), Sjogren (80%).

anti-ds-DNA SLE (60-70%, high) Lupus nephritis

Anti-Smith antibody (anti-Sm) SLE (30-40%, high)

Mixed connective tissue disease (MCTD)

Anti-ribonucleoprotein antibody (RNP)

MCTD (95-100%, low) Scleroderma (20-30%, low)

SLE (30%), Sjogren, RA (10%), discoid lupus (20-30%).

Rheumatoid arthritis (RA)

Rheumatoid factor (RF), Anti-CCP Rheumatoid arthritis (50-90%) Other rheumatic diseases,

chronic infections, elderly

Scleroderma Anti-Scl-70 antibody Scleroderma (15-20%, high)

Sjogren syndrome Anti-SS-A/Ro antibody Sjogren syndrome (60-70%, low) SLE (30-40%), RA (10%), subacute cutaneous lupus, vasculitis.

Wegener granulomatosis

Anti-neutrophil cytoplasmic antibody (ANCA)

Wegener granulomatosis (systemic necrotizing vasculitis) (56-96%, high)

Crescentic glomerulonephritis or other systemic vasculitis (eg, polyarteritis nodosa).

Clinical Chemistry

Glucose

HyperglycemiaPhysiologic

hard physical activity,strong emotions, e.g., fear.

Pathologic• Diabetes Mellitus Type 1, 2• Gestational diabetes• Chronic renal failure• Chronic pancreatitis• Glucagonoma• Hyperthyroidism• Pancreatic cancer• Pancreatitis• Hypopituitarism, Hypothyroidism

HypoglycemiaPhysiologic

normal pregnancy (mild)neonates born to diabetic mothers.

Pathologic

Liver necrosis, adrenal cortical hypofunction, hepatic failure.

Fasting blood glucose 70-110mg/dL2 hours post prandial <200 mg/dL

Alanine aminotransferase(ALT, SGPT, GPT)

Reference range: 10 - 46 U/LIncreased in:

Acute viral hepatitisbiliary tract obstructionLiver cirrhosisDrugs

Aspartate aminotransferase(AST, SGOT, GOT)

Reference range: 10 - 40 U/LIncreased in:

Acute viral hepatitis biliary tract obstruction (cholangitis, stone)cirrhosis Acute myocardial infarctionProgressive muscle diseaseHemolytic anemiaDrugs

ALT + AST

Viral Hepatitis• ↑20-50 even 100 times• Before clinical manifestations• Peak: 7th-12th day ↓ normal at 3th-5th week.• ALT>ASTToxic hepatitis: • as viral hepatitisInfectious mononucleosis + liver involvement: • ↑ ALT & AST up to 20 times

ALT + AST

Biliary obstruction:• ALT & AST higher in extrahepatic and chronic

obstructionCirrhosis: • ALT & AST: high normal ↑5 times• AST>ALTMalignancy• ALT & AST: normal ↑5-10 times

Bilirubin

DierctRR: 0.1-0.3 mg/dLIncreased in:

Bile duct obstructionHepatitisCirrhosisIntrahepatic cholestasis

IndirectRR: 0.1-0.7 mg/dL Increased in:

Crigler-Najjar syndromeGilbert's diseaseHemolytic anemiaHemolytic disease of the

newbornHepatitisPhysiological jaundiceTransfusion reaction

Albumin

Reference range: 3.5-5.2g/dL

Increased in: Dehydrationhemoconcentration.

Decreased in:Decreased hepatic synthesis

chronic liver disease, malnutrition, malabsorption

Increased losses nephrotic syndromeburnsenteropathy

Total Protein

Reference range: 6.3 - 8.2 g/dlIncreased in:

marked dehydration.

Decreased in: Protein-losing enteropathieschronic liver diseaseacute burnsnephrotic syndromesevere dietary protein deficiencymalabsorption syndrome

Alkaline phosphatase

Reference range: 45 - 150 U/LALP is found in liver, bone, intestine, and placenta.Liver• bil obstruction – extrahepatic : ↑↑ 3 times e.g. stone, cancer head of

pancreas)– Intrahepatic ↑↑ < 3 times (drugs, invasion by cancer

tissue)• Moderate ↑ to normal: parenchymal cells of liver

affected e.g. infectious hepatitis

Alkaline phosphatase

Bone• Physiologic– Children: growing bones– Healing bone fracture

• ↑↑ 10-25 times: Paget• Moderate ↑: Osteomalacia• 2 times: Rickets• Normal: Osteoporosis

Pregnancy: 3rd trimestre: 2-3 times

CreatinineReference range:

0.5-1.2 mg/dLIncreased in:

Acute or chronic renal failureurinary tract obstructionnephrotoxic drugs

Decreased in: Reduced muscle mass.

Creatinine clearanceRefernce range• Men

– Range: 97-137 ml/min/1.73 m2 • Women

– Range: 88-128 ml/min/1.73 m2

Increased in: High cardiac outputexercise

Decreased in: Acute or chronic renal failuredecreased renal blood flow (shock, hemorrhage, dehydration, CHF). Nephrotoxic drugs.

Uric acid

Increased in: Decreased renal excretion of Uric Acid

Primary idiopathic HyperuricemiaChronic Renal InsufficiencyDehydration or starvation ketosisDrugs

Overproduction of Uric AcidHGPRTase deficiencyMyeloproliferative disorderLymphoproliferative disorderChemotherapy

Decreased in: DrugsSIADHHemochromatosisProtein or purine deficient diet

Reference Range:Males: 3.4 to 7.0 mg/dLFemales 2.4–6.0 mg/dL

Urea

Reference Range: 20-40 mg/dlIncreased in:

intake of high-protein diet 12 hours before blood samplingRenal failure (acute or chronic)urinary tract obstructiondehydration, Nephrotoxic drugs (eg, gentamicin).

Decreased in: Hepatic failure, nephrotic syndrome, Cachexia

CholesterolReference Range:

Desirable: <200 mg/dLBorderline: 200-239 mg/dLHigh risk: >240 mg/dL

Increased in: Primary hypercholesterolemia Secondary disorders:

hypothyroidism, uncontrolled diabetes mellitus, nephrotic syndrome, biliary obstruction, Drugs.

Decreased in: Severe liver disease (acute hepatitis, cirrhosis)malnutritionmalabsorptionfamilial (Gaucher disease, Tangier disease)abetalipoproteinemia

Triglycerides

Reference Range:Desirable: <150 mg/dLBorderline: 150-199 mg/dLHigh risk: 200-499 mg/dLVery high risk: >500 mg/dL

Increased in: PrimaryDMHypothyroidism, nephrotic syndromebiliary tract obstructionDrugs

Decreased in:Tangier diseaseMalabsorptionparenchymal liver diseaseDrugs

CalciumReference Range: 8.5 - 10.3 mg/dLIncreased in:

Hyperparathyroidism, malignancies secreting parathyroid hormone-related protein (PTHrP) vitamin D excess, Bone diseases FamilialDrugs

Decreased in: Hypoparathyroidismvitamin D deficiencyRenal insufficiencymassive transfusionhypoalbuminemia.

CSF glucose and protein

CSF glucose

Reference range: 50 - 80 mg/dL (or 60-70% of the blood glucose).

CSF protein

Reference range: 15–45 mg/dL

Laboratory Hematology

Complete blood count Reference range

(adult) ↑ ↓

WBC 4-11 X109/L InfectionLeukemia

Some infectionsBM failure

WBC differential

Neutrophils: 55-75%Lymphocytes: 25-40%Monocytes: 2-8%Eosinophils: 1-4%Basophils: 0-1%

Bacterial: NeutrophiliaViral: Lymphocytosis

Some infectionsBM failure

Hb Male: 13.5-16 g/dLFemale: 12-15 g/dL

DehydrationPolycythemia

AnemiaBleeding

Platelets 150-450 X109/L Some infectionsThrombocytosis

BleedingThrombocytopenia

Erythrocyte sedimentation rate (ESR)Reference range: Male: <10 Female: <15 mm/h

↑ ↓

Anemiaincreased fibrinogenIncreased abnormal proteinsInflammationInfection

Marked ↑↑Collagen diseasesMalignancyTB

Polycythemia abnormal red cells, eg spherocytosissickle cells Cryoglobulins low fibrinogen

PT (INR) and APTT

PT APTT EXAMPLES

10 - 13.5 seconds, orINR of 0.8-1.1

30 to 45 seconds Reference ranges

↑ Normal Liver disease, ↓vitamin K, ↓factor VII,anticoagulation drug therapy

Normal ↑ ↓factor VIII, IX, or XI, von Willebrand disease

↑ ↑ ↓ factor I, II, V or X, severe liver disease, DIC

THANK YOU