Trichinella Spiralis from a Medical perspective ..

1. Trichinella Spiralis
Ahmed Essam Elsayed
3rd Year Medical Student
MansouraFacultyOf Medicine - Egypt

2. GeographicalDistribution
Cosmopolitan
ParticularlyinEuropeandUS(PIGEatingCountries)
alsoKnowninAfrica,SouthAsia,MiddleEast
ExistinEgypt

3. Morphology
Shape:VerySmall,Thin,White,Slender,NarrowAnteriorEnd.
Mouth:Simple
Esophagus: Cellular

4. Morphology
a)Male
b)Female

5. Morphology
MALE FEMALE
1.5mmx40ц 3mmx80ц
CurvedPosteriorEnd StraightBluntRoundedPosteriorEnd
2LobularCaudalAppendages Vulvaopenatanterior1/5
TerminalCloaca TerminalAnus

6. LifeCycle
Habitat SmallIntestine
D.H Man,Pig,Rodents,otherCarnivorousanimals
I.H Pig,Man,Rodents
R.H Rodents
InfectiveStage CapsuleinPorkMeat
ModeofInfection IngestionofUndercookedPorkMeatinfectedwithT.Capsule

7. LifeCycle

8. LifeCycle

9. LifeCycle
TypesofTransmission:
Man InfectedbyIngestionofUndercookedPorkMeatContaininginfectiveLarvae
Rat InfectedbyEatingFleshofdeadPigsorRatsandbyCannibalism
Pig InfectedbyEatingFleshofOtherPigsinGarbageorIngestionofInfecteddeadPigsandRats

10. LifeCycle
TrichinellaSpiralisCapsule (LarvalStageof T.Spiralis)
Shape EllipsoidalorLemonShape
Size 0.5x0.2mm
Sites ActiveStriatedMuscles(Diaphragm,EOM,Tongue,Deltoid)
Content CoiledLarvae(80–120цgrowsto900–1300ц)
Infection
BecomeInfectiveafter17DaysFromReachingMuscles
BecomeCalcifiedafter18MonthsFromReachingMuscles
,,ButLarvaeRemainViableinsideitForYears,,

11. Pathogenesis
Lightinfection: lessthan10larvae/gmmuscle>>asymptomatic
Heavyinfection: 50–100larvae/gmmuscle>>symptomatic

12. Pathogenesis
Stages:
• Stageofintestinalinvasion:
adultfemalespenetratemucosa
• Stageofmigration:
larvalmigration
• Stageofmuscularpenetrationandencystment:
larvaeinsidemusclecells

13. Pathogenesis

14. Pathogenesis

15. Pathogenesis

16. ClinicalPicture
1-Intestinalphase:
• 1st weak
• Intestinalinvasionofadultworms
• Foodpoisoninglikesymptoms:
anorexia
nausea
vomiting
sweating
colic
diarrhea
terminatewithfacialedemaandfever.

17. ClinicalPicture
2-Trichinosis:
• 2nd week–3rd week
• Larvalmigration,depositionandencystment
• Tetradoftrichinosis
1-myositis(Ms.Painandweaknessinvolvingactiveskeletalmuscles)
2-facialandperiorbitaledema(duetotoxicvasculitis)
3-fever
4-eosinophilia

18. ClinicalPicture
3-Finalstage:
• Larvaeundergoescompleteencystation
• Allsymptomssubside
• Deathmayoccurinseverecasesdueto
myocarditis
encephalitis
pneumonia

19. ClinicalPicture

20. ClinicalDiagnosis
Historyofeatingraworundercookedporkmeat
Foodpoisoningsymptomsingroupofpersonsduring1st week

21. LaboratoryDiagnosis
1-During1st week:stoolexamination
2-During2nd week:peripheralbloodsampleofmigratinglarvae
3-during3rd week:musclebiopsy
*site>>superficialmusclesasdeltoid
*muscleexaminedby>>
compression,sectioning,digestion

22. LaboratoryDiagnosis
4-Bachman’sTest:
Timing After2Weeks
AgPreparation PurifiedExtractofLarvaecollectedbyDigestionofinfectedpig’sMeat
Method IntraDermalInjectionof0.1mlAgintheForearm
Result ImmediateReactionintheformofWheelSurroundedbyErythemawithin20-30min

23. LaboratoryDiagnosis
5-DirectBloodFilm:Eosinophilia(50%)
6-Xenodiagnoses: infectedmaterialisfedtolabuninfectedrat
after 1monthkilled,examineforT.CapsuleinitsMS
7-SerologicalTests:(ELISA,IHA,CIEP,BentoniteFlocculationTest)

24. Treatment
1-SupportiveTreatmentinBed:SedativeForHeadacheandMSPain
2-Thiabendazole
3-Mebendazole
4-Corticosteroids:ReduceinflammatoryreactionsofMyocarditis,CNSInvolvement

25. Treatment

26. Prevention&Control
1–ProperCookingofPork
2–RegularInspectionbyTrichiniscopy
3-FreezeofPorkMeatat-15Cfor20daystoKillLarvae
4-ControlofRodents

27. ThankYou!