Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The image shown was obtained from parasite samples obtained from a 48 year old m

ID: 194882 • Letter: T

Question

The image shown was obtained from parasite samples obtained from a 48 year old man who traveled to several countries in South America and parts of India within a one month period. He was there for his business. He did not visit rural areas but remembers being bitten by several insects. His infectious disease doctor suspects Trypanosoma cruzi or Leishmania sp. infection but needs definitive diagnosis. Which of the diagnostic methods below can provide definitive information?

A.Immunofluorescence and ELISPOT

polymerase reaction and xenodiagnosis

complement fixation and dot blot assay

ELISA and western blot

The image shown was obtained from parasite samples obtained from a 48 year old man who traveled to several countries in South America and parts of India within a one month period. He was there for his business. He did not visit rural areas but remembers being bitten by several insects. His infectious disease doctor suspects Trypanosoma cruzi or Leishmania sp. infection but needs definitive diagnosis. Which of the diagnostic methods below can provide definitive information?

A.Immunofluorescence and ELISPOT

b.

polymerase reaction and xenodiagnosis

c.

complement fixation and dot blot assay

d.

ELISA and western blot

Explanation / Answer

Correct answer would be:b.polymerase reaction and xenodiagnosis

Reason:PCR helps to amplify small fagments of the parasite DNA that may be present in human blood post an infection.Xenodiagnosis is a technique moslty used in parasitological research to study infection caused by leishmania sp, or trypamosoma sps.This technique is mostly used when direct and definitive demonstration of the presence of a causative agent in a parasite infected patient becomes difficult.In this technique,doctor allows a triatominae which is a vector of the flagellate(trypanosoma), to take a blood meal from the patient and then inspection of the gut of the triatominae is done to look for growth of Trypanosoma cruzi.