Comparative Efficacy of Nutrient Agar Plate Culture and Formalin Ether Concentration Methods in the Laboratory Diagnosis of Human Trichostrongyliasis

Trichostrongyliasis is a zoonotic disease caused by Trichostrongylus species. This nematode is common among domestic and wild herbivores which can also infect human. Low rate infections may be missed during laboratory diagnosis. Nutrient agar plate culture is efficient for the diagnosis of strongyloidiasis, but it has not been evaluated for diagnosis of trichostrongyliasis.

This study was undertaken to compare the efficacy of agar plate culture and formalin-ether concentration methods in laboratory diagnosis of human trichostrongyliasis.

: During 2013-2014, a total of 970 fresh stool samples were collected from Giulan, Mazandaran and Khouzestan Provinces, and also from patients referred to Helminthological Laboratory of School of Public Health, Tehran University of Medical Sciences. All samples were examined for infectivity with Trichostrongylus  by nutrient agar plate culture and formalin ether concentration methods.

Considering parasitological results as gold standard, agar plate culture could detect 45 true positive Trichostrongylus infected cases. The sensitivity and specificity of agar plate culture and formalin ether concentration were 88.23% and 62.75%; and 98.12% and 100%, respectively.

Agar plate culture can be used to detect Trichostrongylus larvae. Its sensitivity is higher than formalin-ether method, but its specificity is lower.

Conflict of interest: None declared.