Transcript Blood parasites.ppt

Blood Parasites
Different stages of Haemoflagellates
African sleeping sickness
Trypanosoma brucei rhodesiense: East Africa,
wild and domestic animal reservoirs
Trypanosoma brucei gambiense: West and
Central Africa, mainly human infection
African Trypanosomiasis
Life cycle of Trypanosoma
brucei gambiense & T. b. rhodesiense
Animal reservoir hosts for African sleeping sickness
Tsetse fly
Pathology and clinical picture
1. Skin stage: chancre.
2. Haematolymphatic stage: generalized
lymphadenopathy, anaemia, generalized
organ involvement.
3. Central nervous system stage (CNS):
Meningoencephalitis.
(Development of the disease more rapid in
Trypanosoma brucei rhodesiense)
chancre
Winterbottom’s stage
rd
3
stage CNS
Lymph node aspirate
trypanosoma
CSF
AMERICAN TRYPANOSOMIASIS
LIFE CYCLE OF Trypanosoma cruzi
Reduviid (Triatomine) bug
T. cruzi causes cutaneous stage (chagoma)
Ocular lesion (Romana’ sign)
C-shape
Heart damage
due to American
trypanosomiasis
Diagnosis
• Blood film
• Serology: IFAT
• Xenodiagnosis: feeding bugs on a suspected
cases.
TREATMENT
African trypanosomiasis
For early infection
• pentamidine
• suramin
For late infection
• eflornithine (Diflouromethylornithine- DFMO)
American trypanosomiasis (Chagas disease)
• benznidazole
• nifurtimox
FILARIALIASIS )
LYMPHATIC FILARIASIS
MAJOR FILARIAL INFECTIONS OF HUMANS
species
Disease
Geographic
distribution
Location of
adult in
humans
Location of
microfilaria
vector
Lab.
diagnosis
Wuchereria elephantiasis
bancrofti
Tropical
and
subtropical
areas
Lymphatic
vessels
Blood
(nocturnal
periodicity)
mosquitoes
Blood
film
Brugia
malayi
elephantiasis
Asia
Lymphatic
vessels
Blood
(nocturnal
periodicity)
mosquitoes
Blood
film+ICT
Onchocerc
a volvulus
Onchocerciasis
(river
blindness)
Africa,
Central
and South
America,
Yemen
Subcutaneous
Skin, eyes,
no
periodicity
Simulium
spp. (black
fly)
Skin snip
Loa loa
loiasis
Central
Africa
Moving in
Blood
subcutaneous (diurnal
tissues
periodicity)
Chrysops
spp. (deer
fly)
Blood
film
nodules
Onchocerciasis (river blindness)
Pathology:
Adults worms live in subcutaneous nodules.
Main pathology caused by microfilariae in:
• Skin: dermatitis
• Lymph nodes: lymphadenopathy
• Eyes: blindness
Diagnosis: skin snip to identify microfilariae.
Treatment: Ivermectin
Lymphatic Filariasis
LYMPHATIC FILARIASIS
Mainly caused by Wuchereria bancrofti
and Brugia malayi
Pathology:
Due to adult worm obstructing lymphatics.
• Acute: lymphadenitis lymphatic varices
• Chronic: lymphedema, hydrocele, chyluria.
LYMPHATIC FILARIASIS
Diagnosis: detection of
microfilariae in blood in
early stages of the disease:
Blood film, Knott’s method
( concentration of 1 ml of
blood), best 10 pm to 2 am
(nocturnal periodicity).
Immunological tests:
Treatment:
diethylcarbamazine
(DEC) or ivermectin
Loa loa
Loiasis
Loiasis
• Pathology: Adult worm
continously migration in
subcutaneous and subconjuntival
tissues, causing Calabar
swellings (allergic reactions) and
conjunctivitis.
Loiasis
• Diagnosis: detection of microfilariae in blood
film.
• Treatment: diethylcarbamazine (DEC) or
ivermectin, surgical remonval.