Trypanosome Ab

Keywords: Trypanosome antibody

Specimen:

5-10 mL blood in plain tube.

Method:

IF, IHA, EIA.

Application:

Diagnosis of chronic infection with Trypanosoma cruzi, the causative agent of Chagas’ disease (American trypanosomiasis), screening of blood donors from endemic areas.

For diagnosis of acute infection with T. cruzi, direct detection of the organism is the appropriate test.

For African trypanosomiasis, caused by T. brucei gambiense and T. brucei rhodesiense, serology is neither sensitive nor specific enough to be reliable for diagnosis in individual patients, although it is used for epidemiological studies.

Interpretation:

The sensitivity of the rest varies with the stage of infection.

Serology does not become positive until 2-8 weeks after infection with T. cruzi. A positive test provides evidence of infection at some time, but does not differentiate acute from chronic disease.

False positives may occur in Leishmaniasis and Syphilis.

A negative result is useful to exclude chronic Chagas’ disease.

Reference:

Barrett MP et al. Lancet 2003; 362: 1469-1480.

Stich A et al. BMJ 2002; 325: 203-206.