Resumen

PABON, Rosalba et al. Evaluation of the Now® malaria ICT P.f/P.v. test for the diagnosis of malaria in Venezuela. Bol Mal Salud Amb [online]. 2007, vol.47, n.2, pp.169-176. ISSN 1690-4648.

We evaluated the Now® malaria ICT P.f/ P.v. test in symptomatic malaria patients from two different endemic areas of Venezuela: Sucre state in the northeastern costal region (n=71) and the Amazonas state in the south (n=86). One hundred two patients were positive by thick and thin blood smears, 73 with Plasmodium vivax , 25 with P. falciparum , 2 with P. malariae and 2 with mixed infections. Some 55 blood samples were negative. The sensitivity, specificity, PPV, NPV of the Now® malaria ICT P.f/P.v. test, were 81.4%, 100%, 100% and 74.3%, respectively and a Kappa of 0.75. With blood samples from Sucre state, the sensitivity was 96.3%, the specificity 100%, the PPV 100%, NPV 89.5% and a Kappa of 0.93 for P. vivax. In Amazonas State, the sensitivity was 81%, the specificity and PPV 100%, the NPV 90.5% and a Kappa of 0.85 for P. vivax and P. malariae. This sensitivity increased for P. vivax when parasitaemias were above 101 parasites/uL. For P. falciparum , the sensitivity was 51.9%, the specificity 100%, the PPV 100%, NPV was 74.5% and a Kappa of 0.56. The sensitivity was 100%, with more than 500 parasites/mL for this species. The high concordance found in this test with the thick and thin blood smear for all malaria species except P. falciparum gives an additional value to this dipstick, along with other well known characteristics such as the rapid and easy handling and interpretation in areas of difficult access. We concluded that the immunochromatographic test is a valuable additional diagnostic tool for malaria but not a substitute of the classical thin and thick blood smear.

Palabras clave : Malaria; diagnosis; immunochromatographic test; Venezuela.