Interpretation ofInterpretation ofInterpretation ofInterpretation ofMedical ParasitologyMedical ParasitologyMedical Parasitology Medical Parasitology

LaboratoryLaboratoryyy

Color Range of Fresh Stool Specimens

Fecal Examination : MacroscopyFecal Examination : MacroscopyColor Range of Fresh Stool Specimens

Color Possible Cause

Black Iron or bleeding in the bowel

Dark Brown Range of normal colors

Brown Range of normal colors

Pale Brown Range of normal colors

Reddish Brown Presence of blood, ingestedmaterial

G i h I t d t i l id t itGreenish Ingested material, rapid transitthrough the bowel

Clay Residual barium, biliary obstruction

Other(Blue, red, purple)

Special medications

Fecal Examination : MacroscopyFecal Examination : MacroscopyTerms Used for Macroscopic Exam of StoolConsistency ReferenceHard Cannot be punctured with an

applicator stickFormed Maintains shape, can be

puncturedSemi-formed Bottom side flattens in the

containerSoft Can be cut with an applicator

stickMushy Can be reshaped with an

li t ti kapplicator stickLoose Stool shapes to the containerDiarrhea Stool will flow slowly out of the

icontainerWatery Fluid-like stool pours out of the

container

Fecal Examination : MicroscopyFecal Examination : Microscopy

Classification of Worm Infestation by Classification of Worm Infestation by U i E CU i E CUsing Egg CountsUsing Egg Counts

LightLight ModerateModerate HeavyHeavyLightLight ModerateModerate HeavyHeavy

A iA i 5 0005 000 5 0005 000 50 00050 000Ascaris Ascaris lumbricoideslumbricoides

< 5.000< 5.000 5.000 5.000 --50.00050.000

> 50.000> 50.000

Trichuris Trichuris trichuiratrichuira

< 1.000< 1.000 1.000 1.000 ––10.00010.000

> 10.000> 10.000

Hook WormHook Worm < 2.000< 2.000 2.000 2.000 ––7.0007.000

> 7.000> 7.000

Specimen Type Examination Technique Possible Parasites

Parasitological ExaminationParasitological ExaminationCellophane Tape Prep Direct Exam Enterobius vermicularis

Sigmoidoscopy Material Direct ExamPermanent Stain

Entamoeba histolyticaIntestinal ProtozoaC t idiCryptosporidium parvum

AspiratesDuodenalLiver or Lung Abscess

Direct ExamPermanent StainDirect Exam

Giardia IambliaIsospora belliStrongyloides stercoralise o u g bscess

Liver or Lung CystBronchoscopy Material

ect aPermanent StainCultureDirect Exam with KOHCentrifuged, Direct Exam

St o gy o des ste co a sCryptosporidium parvumEntamoeba histolyticaEntamoeba histolyticaEntamoeba histolyticag ,

Permanent Stainy

Echinococcus speciesPneumocystis cariniiToxoplasma gondiiCryptosporidium parvumyp p p

Sputum Direct ExamN-acetyl-cysteine

concentrate

Paragonimus westermaniStrongyloides stercoralisAscaris lumbercoidesconcentrate Ascaris lumbercoidesHookwormEntamoeba histolyticaEchinococcus species

Parasitological ExaminationParasitological ExaminationSpecimen Type Examination Technique Possible ParasitesMouth Scrapings Direct Exam

P S iEntamoeba gingivalisT i h tPermanent Stain Trichomonas tenax

Nasal Discharge Direct ExamPermanent Stain

Naegleria fowleriNaegleria fowleri

Corneal Scrapings CultureCalcofluor White StainHistologic Processing

Acanthamoeba speciesAcanthamoeba speciesAcanthamoeba species

Ti Bi C lt L i h i iTissue BiopsySkin UlcerSkin SnipLymph Node

CultureHistologic ProcessingDirect ExamHistologic Processing

Leishmania speciesLeishmania speciesOnchocerca volvulusMansonella streptocercay p g g

Histologic Processingp

Leishmania speciesTrypanosoma speciesToxoplasma gondii

Parasitological ExaminationParasitological ExaminationTissue Biopsy (continued)Bone MarrowMuscle

Histologic ProcessingPermanent StainHistologic Processing

Leishmania speciesTrypanosoma speciesToxoplasma gondiiMuscle Histologic Processing Toxoplasma gondiiTrichinella spiralis

Urine Centrifuged Direct Exam Schistosoma haematobiumhaematobium

MicrofilariaeTrichomonas vaginalis

Urethral Discharge Direct Exam Trichomonas vaginalisg gVaginal Discharge Direct Exam Trichomonas vaginalisProstatic Secretions Direct Exam Trichomonas vaginalisBlood Direct Exam Plasmodium speciesBlood Direct Exam

Permanent StainPlasmodium speciesBabesia speciesLeishmania speciesTrypanosoma speciesMicrofilariae

Malaria diagnosisMalaria diagnosisLaboratory DxLaboratory Dx

Blood filmBlood film RDT (RapidRDT (RapidBlood film Blood film (microscopic)(microscopic)

–– Gold standardGold standard

RDT (Rapid RDT (Rapid Diagnostic Test)Diagnostic Test)

–– Dipstick Dipstick –– Sensitivity 40 Sensitivity 40

parasites/parasites/μμll

pp–– Antigen detection:Antigen detection:

»» HRPHRP--2 detection 2 detection LDH ALDH A

PCRPCRS i i i 4S i i i 4

»» pLDH Ag pLDH Ag »» PanPan--malaria Agmalaria Ag

–– Sensitivity Sensitivity ±±100 100 –– Sensitivity up to 4 Sensitivity up to 4

parasites/parasites/μμll

yyparasites/parasites/μμll

Malaria diagnosisMalaria diagnosisCalculationCalculation

Calculation and identification can both derivedCalculation and identification can both derivedCalculation and identification can both derived Calculation and identification can both derived from thick and thin blood filmfrom thick and thin blood filmAsexual stages (rings, trophozoites, andAsexual stages (rings, trophozoites, andAsexual stages (rings, trophozoites, and Asexual stages (rings, trophozoites, and schizonts) counted togetherschizonts) counted togetherSexual stage (gametocytes) counted separatelySexual stage (gametocytes) counted separatelyg (g y ) p yg (g y ) p y

Malaria diagnosisMalaria diagnosisCalculationCalculation

11 Semi quantitative:Semi quantitative:1.1. Semi quantitative:Semi quantitative:((--)) no parasites in 100 fieldsno parasites in 100 fields(+)(+) 11 10 parasites in 100 fields10 parasites in 100 fields(+)(+) 11--10 parasites in 100 fields10 parasites in 100 fields(++)(++) 1111--100 parasites in 100 fields100 parasites in 100 fields(+++)(+++) 11 10 parasites in 1 field10 parasites in 1 field(+++)(+++) 11--10 parasites in 1 field10 parasites in 1 field(++++)(++++) >10 parasites in 1 field>10 parasites in 1 field

Malaria diagnosisMalaria diagnosisCalculationCalculation

22 Based on leucocytes countBased on leucocytes count2.2. Based on leucocytes countBased on leucocytes count–– Thick blood filmThick blood film

Number of parasites inNumber of parasites in ≥≥200 leucocytes200 leucocytes–– Number of parasites in Number of parasites in ≥≥200 leucocytes 200 leucocytes –– (n/200) x 8,000 parasites per (n/200) x 8,000 parasites per μμl bloodl blood

H perparasitemia: parasites ≥250 000H perparasitemia: parasites ≥250 000–– Hyperparasitemia: parasites ≥250,000 Hyperparasitemia: parasites ≥250,000 parasites per parasites per μμl bloodl blood

Malaria diagnosisMalaria diagnosisCalculationCalculation

33 Based on erythrocytes countBased on erythrocytes count3.3. Based on erythrocytes countBased on erythrocytes count–– Thin blood smearThin blood smear

Number of parasites inNumber of parasites in ≥≥1000 erythrocytes1000 erythrocytes–– Number of parasites in Number of parasites in ≥≥1000 erythrocytes1000 erythrocytes(n/1,000) x 4(n/1,000) x 4,,55000,000 parasites per 0,000 parasites per μμl bloodl bloodHyperparasitemia: parasites ≥5% or 50Hyperparasitemia: parasites ≥5% or 50–– Hyperparasitemia: parasites ≥5% or 50 Hyperparasitemia: parasites ≥5% or 50 parasites in 1,000 erytrocytesparasites in 1,000 erytrocytes

Rapid DiagnosisRapid Diagnosisp gp g

Rapid DiagnosisRapid DiagnosisRapid DiagnosisRapid Diagnosis

1 2 31. 2. 3.

Results.Results.

Negative Positive

THE END!Thank You