Trichinella Spiralis & Onchocerca.ppt111

7/25/2019 Trichinella Spiralis & Onchocerca.ppt111

1/29

1


2/29

2


3/29

Tissue Nematoda

Adult in tissues Larva in tissues

Lymphatic subcutaneous tissues

Filarial worms

Wuchereria

bancrofti.

Wuchereria

malayi.

Loa loa.

Onchocercus

volvulus

serous cavities

Mansonella

species

Trichinella spiralisToxocara canis &

cati (visceral larva

migrans).Ancylostoma

caninum &

brailiense(cutaneous larva

migrans)Larvae of filariae

(microfilaria in

bloo!)

3Dr. Mona El Sobky

subcutaneous tissues

Loa loa.

Onchocercus

volvulus

serous cavities

subcutaneous tissues


4/29

Distribution:

World wide specially in pork eating countries.

Deinitive host:

!igs" rats # sometimes man.

$ntermediate host:!igs" rats # sometimes man.

%abitat: Adultslive in the small intestine.

Males in lumen & femalesin tissues (embedded in submucoa).

Larvaelive mainly in active striated muscles.

4Dr. Mona El Sobky

Trichinella spiralis


5/29

&mall thread like nematode.

Thin anterior part which becomes

gradually thickened posteriorly.

&imple mouth.

'ellular oesophagus ()*+ the body

length.

,eneral characters

5Dr. Mona El Sobky


6/29

-ale:

&horter than emale .

!osterior end coiled.

ne set o genitalia.

Two conical papillae at

post. end.

6Dr. Mona El Sobky


7/29

Female:

!osterior end is blunt .

ne set o genitalia.

/ulva opens anteriorly at

the ventral side.

Larviparous.

7Dr. Mona El Sobky


8/29

Larva:

0.) mm. long.

1habditiorm oesophagus.

!asses in stool sometimes.

!asses to the blood to reach muscles

# becomes encysted.

8Dr. Mona El Sobky


9/29

2ncysted T. spiralislarva in muscles ($.&3:

) mm. long.

'oiled.Live in active striated muscles as eye lid"

tongue" ms o mastication" deltoid"

diaphragm # intercostal ms.

&urrounded by a ibrous capsule (made by

the host3.

The cyst lies in between # parallel to

muscle ibres.

The encysted larvae become calciied in 45

)6 months.

9Dr. Mona El Sobky


10/2910

Dr. Mona El Sobky


11/29

-ode o $nection

). 1ats are inected by eating inected pig muscles in

garbage containing encysted T. spiralis larva or

eating inected rats by cannibalism.

6. !igs are inected by eating meat o dead pigs or dead

rats containing encysted T. spiralislarva.

+. -an is inected by eating undercooked pork meat"

containing encysted T. spiralislarva.

11Dr. Mona El Sobky


12/29

!athologenesis # &ymptomatology

Disease: Trichinellosis" trichiniasis

The symptoms vary depending on the

amount o encysted larvae ingested" age

and host immunity.

There are two main phases or inection:5

)5 2nteral phase (aecting the intestine3.

65 !arenteral phase: (outside the intestine3.

12Dr. Mona El Sobky


13/29

)5 2nteral phase

(Aecting the intestine3

Light inection usually asymptomatic.

%eavy inection produces symptoms such as

nausea" vomiting" dyspepsia" abdominal pain and

diarrhea (like ood poisoning3.

This phase occurs in the )stweek ater inection.

2osinophilia detected early and increased.Larvae can be detected in the stool.

13Dr. Mona El Sobky


14/29

65 !arenteral phase

(utside the intestine3

Larvae migrate in the blood invade dierent tissue initiate

inlammatory reaction and presented by:5

Fever and urticarial rash due to to7aemia.-uscles:!ain and tenderness o the aected muscle:5 2ye lids periorbital oedema (a classic sign3" subcon8uctival

haemorrhage and diiculty in eye movement. Tongue diiculty in speaking and dysphagia. Diaphragm and intercostals muscles diiculty in breathing. -uscles o mastication

diiculty in mastication.&plinter haemorrhage under the nails (a common symptom3Laryn7: %oarseness o voice.%eart: -yocarditis may lead to heart ailure.Lung: !neumonia.9rain: 2ncephalitis and meningitis.$n severe cases" death can occur 54 weeks ater the inection and is

usually caused by myocarditis" encephalitis or pneumonia.

2osinophilia:605;0


15/29

Dr. Mona El Sobky 15

Splinterhaemorrhage under

the nail

Periorbital oedema


16/29

Laboratory Diagnosis

Direct $ndirect&tool e7amination: For larvae or adult.

9lood e7amination: For larvae.

-uscle biopsy: Taken rom the swollen

tender part # compressed between two

slides ater digestion in acid pepsin to

see larvae .

Trichinoscopy:To see larvae in muscle.

= ray or calciied cyst.

'Tor brain lesions.

$ntradermal test (9achman test3.

&erological tests: 'FT" $%A" $FAT"

2L$&A.

2osinophlia (605;0


17/29

Treatment

,eneral treatment &peciic therapy

9ed rest and luid therapy

&edatives or headache

and muscle pain.

'orticosteroids to reduce

inlammatory reaction.

'ardiac and respiratory

monitoring.

Thiabenda>ole.

-ebenda>ole.

17Dr. Mona El Sobky


18/29

Onchocercus volvolus(1iver 9lindness worm3

,eographical distribution: &udan" &audi Arabia" ?emen and 'entral

America.

%abitat:

Adultinhabits subcutaneous tissues over boney prominences.

-icroilariaedoes not reach the circulation" they are present in the

dermis" subcutaneous nodules" subcutaneous tissues" all chambers

o the eye and they are non periodic.

D.%:-an.

$.% (vector3: Female9lack lies ("imulium3.

18Dr. Mona El Sobky


19/29

-orphological characters

$. Adults (D.&3:

-ale: shorter than

emale.

Female: Layes

micriilaria in

subcutaneous

nodules.

19Dr. Mona El Sobky

&ection in skin nodule

shows emale uteri ull o

microilaria


20/29

$$. -icroilaria (D.&3:

&mooth curves.

Non sheathed.

Anterior end # tail ree o nuclei.

Not ound in blood but ound in

subcutaneous nodule # eye

chambers.

$$$. Filariorm larva ($.&3: in the mouth

parts o black ly.

20Dr. Mona El Sobky


21/29

21Dr. Mona El Sobky


22/29

!athogenesis and symptomatology

Disease: nchocercosis or river blindness.

)5 'utaneous lesions

nchocerca nodule

(onchocerchoma ):

Fibrous subcutaneous

nodules over bony

prominences as scalp"

elbow" knee" ribs" iliac crest

# scapula.

Firm rounded or oval.

'ontaining adults and

microilariae

The skin over and near

nodules shows sever

dermatitis" an intense itching

and may lead to 6ry

inection.

&kin may be depigmented

(Leopard3 or hyper

pigmented (&owda3 with

oedema.

The lymph nodes in

emoral triangle are

enlarged (in males and

emales3 (hanging

groin3 with loss o skin

elasticity (sagging o

the skin3.

22Dr. Mona El Sobky


23/29

nchocerca nodulenchocerca nodule

nchocerca nodulehanging groin 23Dr. Mona El Sobky


24/29

&owda (hyperpigmentation3

Leopard (%ypopigmentation3 24Dr. Mona El Sobky


25/29

65 2ye lesions

Due to immunologic response to microilaria that

invade the eye.

-icroilaria invades many parts o the eye

keratitis with corneal opacity iridocyclitis"

chorioretinitis with degenerative changes and

optic neuritis blindness.

25Dr. Mona El Sobky

1iver blindness or &udanese blindness


26/29

1iver blindness or &udanese blindness

26Dr. Mona El Sobky


27/29

Laboratory diagnosis

Direct

Demonstration o

microilaria in aspirate o

nodules or skin snips.

Demonstration o adult in

e7cised nodule.

2ye e7amination: presence

o microilariae in cornea and

eye chambers.

$ndirect

2osinophilia (60


28/29

Treatment

&urgical removal o the nodule.

%etra>an.

$vermectin (Drug o choice3.

28Dr. Mona El Sobky


29/29

29Dr Mona El Sobky

Trichinella Spiralis & Onchocerca.ppt111

Documents

Transcript of Trichinella Spiralis & Onchocerca.ppt111