[Lab] Hemoflagellates Part 1 Flashcards
Enumerate the 3 Trypanosoma
- Trypanosoma brucei gambiense
- Trypanosoma brucei rhodesiense
- Trypanosoma cruzi
4 stages of development of Hemoflagellates
- Amastigote or Leishmania form (Donovan
Leishman) - Promastigote or Leptomonas form
- Epimastigote or Crithidia
- Trypomastigote or Trypanosoma
Describe Amastigote or Leishmania form (Donovan Leishman)
- Ovoidal without free flagellum (no flagella)
- Intracellular
Describe Promastigote or Leptomonas form
- Elongated and spindle-shaped
- Pointed end with a free flagellum arises from the kinetoplast at the anterior end
Describe Epimastigote or Crithidia
- Elongated and spindle-shaped
- Free flagellum continues from the anterior end
backward along the margin of the undulating
membrane and the ends of the kinetoplast which is situated anterior to the nucleus
The Trypomastigote or Trypanosoma has the same morphological structure as the Epimastigote or Crithidia
Yes but without the flagellum
True or false: Genus Leishmania: amastigote & promastigote
True
True or false: Trypanosoma brucei group: epimastigote trypomastigote
True
True or false: Trypanosoma cruzi: amastigote & promastigote
False (all stages)
True or false: Trypanosomes are nonpathogenic
False (pathogenic)
True or false:
Trypanosoma brucei group:
Invertebrate host – epimastigote
Mammalian host (blood) – trypomastigotes
True
True or false: Trypanosoma cruzi:
Invertebrate host, mammalian host (blood)
- trypomastigotes in the gut
- amastigotes intracellularly in the mammalian
host
- epimastigote in the midgut of the invertebrate
host.
True
Motility of Trypanosomes
Minute, active, wavy spiral
Shape of Trypanosomes
Fusiform, flattened from side to side
Nucleus of Trypanosomes is small
No, large
Karyosome of Trypanosomes
Central
True or false: Amastigotes are intercellular forms, which have lost the undulating membrane and flagellum.
False (intracellular)
Location of Amastigotes
Reticuloendothelial cells
Kinetoplast of Amastigotes
Spherical/rodlike
Vertebrate host of T. brucei
Man
Invertebrate host of T. brucei
Tsetse flies
Diagnostic stage of T. brucei
Trypomastigote
Infective stage of T. brucei
Metacyclic trypomastigote
MOT of T. brucei
Bite of tsetse flies
Diagnostic and infective stage of T. cruzi
Same as T. brucei
Invertebrate host of T. cruzi
Reduviid bugs
- Rhodnius
MOT of T. cruzi
- Bites of Reduviid bug
- Blood transfusion
3.. Transplacental transfer
Diseases caused by Trypanosoma brucei gambiense
- West African Sleeping sickness
- Gambian trypanosomiasis
Diseases caused by Trypanosoma brucei rhodesiense
- East African Sleeping sickness
- Rhodesian trypanosomiasis
Diseases caused by Trypanosoma cruzi
- Chagas disease
- American trypanosomiasis
Signs and symptoms of acute diseases caused by Trypanosomas
- Irregular fever
- Headache
- Joint & muscle pain
- Rash
- Hyperactive
Death due to Trypanosoma diseases are caused by
- Malaria
- Dysentery
- Pneumonia
Clinical manifestations of Chagas disease/Chagoma
- Slightly painful nodule at the site of inoculation.
- Metastatic lesions throughout the body notably in the heart, esophagus and lower intestine.
Signs and symptoms of Chagas disease/Chagoma
- Heart failure
- Megaesophagus
- Megacolon
Symptoms of Chagas disease/Chagoma may last for
20 years and more
True or false: Chagas disease is often fatal in infants
False (older children and adults)
Specimen of interest for Trypanosomas (T. brucei)
- Blood
- Lymph aspirates
- CSF (checked for presence of Mott cells)
Techniques used for the recovery of Trypanosomas
- Stained blood preparations (for T. brucei)
- Thick blood smear with Giemsa stain (for Trypanosomes
- Xenodiagnosis
- Serologic tests (a. Immunofluorescent antibody test
b. Hemagglutination assay) - Novy Mac Neal Nicolle culture medium (T. cruzi)
Treatment for African Sleeping Sickness
- Pentamidine
- Suramin
* Both drugs do not enter the CSF. - Melarsoprol - late stage of the disease with
CNS involvement.
Treatment for Chagas disease
- Nifurtimox
- Bezuidazole
Both are partially effective in acute disease
Epidemiology of African trypanosomiasis
“Tsetse belt” in Africa
Epidemiology of Chagas disease
Central and South America.
Prevention and control of diseases by Trypanosomas
- Reduction of the pool of contact with Tsetse
fly through control measures (traps, screens
insecticides) - Reduction of the pool of human infection by
diagnosis and treatment. - Vector control
- Screening and sterilization of transfusion
blood and health education.
True or false: Leishmania
Occurs as:
intracellular amastigote = Vertebrate host
flagellate promastigote = Invertebrate host
True
3 Leishmania species
- Leishmania tropica
- Leishmania donovani
- Leishmania braziliensis
Where does the amastigote of Leishmania spp live
Living intracellularly in monocytes, PMN or
endothelial cells
No. of flagellum of promastigote of Leishmania spp
1
Invertebrate host of Leishmania spp
- Sandflies
- Genus Phlebotomus
Reservoir hosts of Leishmania spp
Domestic dog, wild animals
Infective stage of Leishmania spp
Promastigote
Diagnostic stage of Leishmania spp
Amastigote
Leishmania tropica = lymphoid tissue of the skin
Yes
Diseases caused by Leishmania donovani
Visceral leishmaniasis
Kala-azar fever
Dumdum fever
Black fever
Death fever
Tropical splenomegaly
Diseases caused by Leishmania tropica
Cutaneous leishmaniasis
Oriental sore
Old World Leishmaniasis
Aleppo Button
Delhi Boil
Baghdad Boil
Jericho Boil
Diseases caused by Leishmania braziliensis
Mucocutaneous leishmaniasis
Espundia
New World Leishmaniasis
Visceral Leishmaniasis is numerous in the reticuloendothelial cells of
Spleen
Liver
Lymph nodes
Bone marrow
Intestinal mucosa
Visceral Leishmaniasis phagocytosed parasites are present only in small
numbers in the blood.
Yes
Clinical manifestations of Visceral Leishmaniasis
Fever
Malaise
Loss of appetite
Diarrhea
Wasting
Ulceration in the skin leaving an ugly scar. Widespread thickening of the skin wherein the
lesion resembles those of lepromatous leprosy. Lesions does not heal spontaneously.
Cutaneous leishmaniasis
Initial lesion at the bite site is papule that later
develop into an ulcer. Metastatic spread may occur on the oronasal and pharyngeal mucosa.
Mucocutaneous leishmaniasis
Highly disfiguring leprosy like tissue
destruction and swelling on the oronasal
Tapir nose
Epidemiology of Tapir nose
Southern regions of America
Mediterranean
East and North Africa
Arabian Peninsula
Persian Gulf
Indian subcontinent
China
Southern Soviet Union
Diagnosis of Tapir nose
- Giemsa or Wright’s stained smear
Specimen: Skin lesions biopsies or aspirates - Culture media
- Montenegro skin test (Leishman skin test)
Culture media for Tapir nose
- Nicole, Novy, Mac Neal (NNN) culture medium;
- Schneider’s,
- Drosophilia medium
- Formol gel test (screening test)
- Serological test (CFT, FAT, Counter-Current Electrophoresis
In Montenegro skin test, what is performed
Intradermal injection of a suspension of killed
promastigotes.
Wheal formation indicates an infection
What is done in Formol gel test
Use of 0.1-ml serum + 1 drop of formalin
Positive result is gel formation
Treatment for Tapir nose
- Pentavalent antimonials
- Sodium stibogluconate
- N-methyl-glucamine antimonate
Secondary drugs/treatment for Tapir nose
- Amphotericin B
- Pentamidine (for Kalaazar fever)
- Metronidazole
- Nifurtimox
Prevention and control for Tapir nose
- Vaccination
- Control of sandfly vectors
- Protective measures from sandflies
- Mechanical destruction of animal reservoir
habitats and poisoning of animals.
