Page 40 - Medical Parasitology_ A Textbook ( PDFDrive )
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32 5 Hemoflagellates
4. Histopathology
Biopsy specimens may reveal amastigotes of T. cruzi.
5. Serodiagnosis
6. Intradermal test
7. Molecular diagnosis
PCR on clinical samples.
Treatment
No effective specific treatment is available for treating Chagas’ disease. Nifurtimox
(5–7 mg/kg daily in 4 divided doses and is increased by 2 mg/kg daily at 2 week
intervals up to a daily dose of 15–17 mg/kg, a total of 120 days treatment is given)
and benznidazole have been used with limited success in both acute and chronic
Chagas’ disease. These drugs kill only the extracellular trypanosomes but not the
intracellular form.
Prevention and Control
1. Insecticide to control the vector bug
2. Insect repellant and use of insect netting
3. Improvement in housing to eliminate breeding places of bugs
Leishmania donovani
Distribution
It causes visceral leishmaniasis or kala azar which is a major public health problem
in many parts of the world.
Habitat
In human, the amastigotes are found in the reticuloendothelial system.
Morphology
The parasite exists in 2 forms.
1. Amastigote form is found in humans and other mammals. The amastigote form
of the parasite seen in human samples is called Leishman Donovan (LD) body
and it is intracellular.
2. Promastigote form is found in the sandfly and in culture.
