7. Hemoflagellates Flashcards
Hemoflagellates Morphologic Forms
- Amastigote
- Promastigotes
- Epimastigote
- Trypomastigote
Roundish and oval; a single, large nucleus that is off-center, sometimes
present more toward the edge of the organism; basal body structure known as BLEPHAROBLAST
Amastigote
Measures 9 to 15 um in length; The large single nucleus is located in or near the center of the long slender body
Promastigote
Slightly wider than that of the promastigote; Large single nucleus is
located at the posterior end
of the organism.
Epimastigotes
Typically measures 12 to 35 um
long by 2 to 4 um wide; May often assume the shape of the letters C, S, or U in stained blood films
Trypomastigote
is an umbrella term that is used to refer to the BLEPHAROBLAST and small parabasal body
Kinetoplast
forms routinely found in human specimens.
Amastigote and trypomastigote
are found primarily in tissue and muscle, and CNS within macrophages, where they multiply
Amastigote
reproduce and are visible in the peripheral blood.
Trypomastigote
may be seen only if blood sample is collected immediately after transmission into a healthy individual or when the appropriate sample is cultured
Promastigote
Specimens of choice:
blood, lymph node and ulcer aspirations, tissue
biopsies, bone marrow, and cerebrospinal fluid.
common name for an infection with Leishmania tropica; it is a cutaneous form of Leishmaniasis presenting with pus-containing ulcers
Baghdad boils
a common name for a cutaneous form of infection caused by
Leishmania mexicana
Bay sore
cutaneous leishmaniasis caused by L. mexicana; commonly
found in Belize, Guatemala, and the Yucatan peninsula in areas where chicle sap is harvested for making chewing gum
Chiclero ulcer
a common reference for the cutaneous leishmaniasis
caused by the infecting agents comprising the Leishmania tropic complex
Oriental sore
– a common name for visceral leishmaniasis caused by Leishmania donovani
Dum dum fever
another name for the most severe form of visceral leishmaniasis caused by
members of the Leishmania donovani complex
Kala-azar
– reference to mucocutaneous leishmaniasis in the Peruvian Andes
Yuta
– another name for an infection resulting from Leishmania braziliensis, the principal cause of mucocutaneous disease in Central and South America, particularly Brazil
Espundia
another name for the infection with Leishmania guyanensis, the principal cause
of mucocutaneous leishmaniasis in the Guianas, parts of Brazil and Venezuela, also
known as pian bois
Forest yaws
a general term for parasitic infection of the blood, into new
environments, finding new host organisms and new vectors
Parasitemia
its organisms are the causative
agent may also be referred to as New World
Leishmania braziliensis complex
are responsible for
transmitting the promastigotes of L. braziliensis complex into unsuspecting
humans via blood meal, resulting in a skin bite.
Lutzomyia and Psychodopygus
The diagnostic stage in humans is the ______ while it serves as the
infective stage for the sandflies.
amastigote
the amastigote
transform back into _____ in the fly midgut and multiply
promastigotes
Large ulcers in the oral or nasal mucosa areas
(mucocutaneous) develop in some patients after the initial invasion of the reticuloendothelial cells.
Mucocutaneous Leishmaniasis
responsible for Mucocutaneous Leishmaniasis
Leishmania braziliensis complex
- Mucocutaneous Leismaniasis specimen of choice:
- Giemsa-stained preparations should reveal
- Biopsy of the Infected Ulcer
- Amastigotes
restriction analysis of the kinetoplast DNA
Schizodeme analysis
nuclear DNA hybridization, and isoenzyme
patterns analysis
Zymodeme analysis
the most widely used treatment for mucocutaneous leishmaniasis.
Antileishmanial agent with antimony compounds
L.braziliensis has shown increased resistance to pentavalent
antimonials such as
sodium stibogluconate (Pentosan)
Organisms of the complex and their diseases may be referred to as Old or
New World
Leishmania donovani complex
L.donovani is capable of being transmitted person to person via
blood transfusion
High levels of _____ in patients successfully treated with visceral leishmaniasis may indicate parasite
remnants.
galactosyl-alpha(1-3)galactose antibodies
L.donovani
primarily affects the _____ of the infected human.
visceral tissue
Also known as kala-azar or dum dum fever; Patients often present with nondescript abdominal illness
and hepatosplenomegaly.
Visceral Leishmaniasis
Visceral Leishmaniasis Onset of symptoms is gradual and follows an incubation
period ranging from _____
2 weeks to 18 months
Used for screening
large populations at risk for infections caused by Leishmania spp.
Montenegro skin test
(Leishmania donovani complex)
Culture of blood, bone marrow and
other tissues may show the
promastigote form
(Leishmania donovani complex)
drug of choice
Liposomal amphotericin B (Ambisome)
(Leishmania donovani complex)
Infected patients with AIDS respond to
allopurinol
- Associated with New World cutaneous leishmaniasis, chiclero ulcer, bay
sore - The diseases and their causative agents maybe referred to as New World because of the geographic location of its members.
Leishmania mexicana complex
New World Cutaneous Leishmaniasis
Leishmania mexicana complex
Characterized by a single pus-containing ulcer, which is generally
self-healing
New World Cutaneous Leishmaniasis
Infections with L.amazonensis have been known to progress to
incurable
DCL form
Associated with diseases and condition namely, Old World Cutaneous
Leishmaniasis, Oriental sores, Delhi boils, Baghdad boils, dry or urban cutaneous leishmaniasis.
Leishmania tropica complex
L.tropica complex primarily attacks the
human lymphoid tissue of the skin
(L.tropica complex)
Microscopic examination of Giemsa-stained slides of aspiration of fluid underneath the ulcer bed for the typical
Amastigote
In L. tropica complex skin test (Montenegro skin test) can be used, however patients with active infection
tests
negative
(L. tropica complex)
Effective treatment is
sodium stibogluconate (Pentosam)
causative agent of the trypanosomal diseases known as nagana and sleeping sickness
Trypanosoma brucie
a form of disease
found in cattles
nagana
West African Sleeping Sickness
Trypanosoma brucie gambiense
two specie of tsetse flies responsible for the transmission of T.b.gambiense
Glosina palpalis and Glosina tachinoides
T.b.gambiense has shown to be acquired through blood transfusion, organ transplantation, and
congenital transmission
Humans become infected with T.b. gambiense following injection of
_______ by the ______ during its blood meal.
- trypomastigotes
- the tsetse fly
First notable symptom is the development of a painful chancre (ulcer), surrounded by a white halo at the bite site.
West African (Gambian) Sleeping Sickness
which refers to the enlargement of the cervical lymph nodes in reference to this trypanosomal disease.
Winterbottom’s sign
a delayed
sensation to pain
Kerandel’s sign
(Trypanosoma brucie gambiense)
Giemsa-stained preparations reveal the typical
trypomastigotes
used for treatment of T.b.gambiense infections.
Melarsoprol, suramin, pentamidine and eflornithine
Commonly associated with East African Sleeping Sickness; More aggressive than that of the West African Sleeping Sickness.
Trypanosoma brucie rhodesiense
Trypanosoma brucie rhodesiense vectors
Glossina morsitans and Glossina pallidipes
Presence of _____ is
diagnostic for T.b.rhodesiense.
IgM
Commonly associated with Chaga’s disease
Trypanosoma cruzi
Trypanosoma cruzi vector
reduviid bug known as “kissing bug”, “conenose bug”, and “triatomid bug”
Edema as well as a rash around the eyes and face may subsequently occur
Chaga’s disease
happens when patients contract T. cruzi through ocular mucosa and develop a characteristic conjunctivitis and unilateral edema of the eyelids
Romana’s sign
is a traditional method of diagnosing T. cruzi
Xenodiagnosis
T. cruzi (chagas disease) treatment of choice
nifurtimox (Lampit)
T. rangeli vector
Rhodinus prolixus
all trypanosoma specie demonstrates _____ in giemsa-stained preparations
trypomastigote
