Question

Tissue-invasive parasitic infections should be considered if a patient has eosinophilia but negative O/P (ova and parasites) testing. Which of the following parasitic infections falls into this category?

a) Giardiasis
b) Toxoplasmosis
c) Schistosomiasis
d) Malaria

Answer 1

Schistosomiasis is the tissue-invasive parasitic infection associated with eosinophilia in the absence of detectable ova and parasites on a stool O/P exam.

Step-by-step explanation:

Tissue-invasive parasitic infections should be considered if a patient exhibits eosinophilia but has negative O/P (ova and parasites) testing. Among the options provided in the question, c) Schistosomiasis is a parasitic infection known for its tissue-invasive properties and may not be readily diagnosed with a stool O/P exam. This infection is caused by trematode worms (schistosomes) and can cause eosinophilia. While Giardiasis and Toxoplasmosis are also significant parasites, they do not typically cause eosinophilia in absence of detectable ova and parasites within the stool. Malaria, caused by Plasmodium species, does not typically present with eosinophilia and would likely be discovered on blood films rather than stool tests.

EIA and ELISA testing can help detect antigens associated with parasitic pathogens like Schistosomiasis when traditional ova and parasite testing is negative due to the parasite's tissue-invasive nature.