ABSTRACT
Whole blood samples (N = 295) were obtained from different locations in Amazonas and Sucre States, in Venezuela. Malaria was diagnosed by microscopy, OptiMAL and polymerase chain reaction (PCR), with Plasmodium vivax, P. falciparum, and P. malariae being detected when possible. We identified 93 infections, 66 of which were caused by P. vivax, 26 by P. falciparum, and 1 was a mixed infection. No infection caused by P. malariae was detected. The sensitivity and specificity of each diagnostic method were high: 95.7 and 97.9 percent for microscopy, 87.0 and 97.9 percent for OptiMAL, and 98.0 and 100 percent for PCR, respectively. Most samples (72.2 percent) showed more than 5000 parasites/æL blood. The sensitivity of the diagnosis by microscopy and OptiMAL decreased with lower parasitemia. All samples showing disagreement among the methods were reevaluated, but the first result was used for the calculations. Parasites were detected in the 6 false-negative samples by microscopy after the second examination. The mixed infection was only detected by PCR, while the other methods diagnosed it as P. falciparum (microscopy) or P. vivax (OptiMAL) infection. Most of the false results obtained with the OptiMAL strip were related to the P. falciparum-specific band, including 3 species misdiagnoses, which could be related to the test itself or to genetic variation of the Venezuelan strains. The use of the microscopic method for malaria detection is recommended for its low cost but is very difficult to implement in large scale, population-based studies; thus, we report here more efficient methods suitable for this purpose.
Subject(s)
Animals , Humans , Malaria, Falciparum/diagnosis , Malaria, Vivax/diagnosis , Plasmodium falciparum , Plasmodium vivax , Parasitemia/diagnosis , Chromatography/methods , Endemic Diseases , Malaria, Falciparum/epidemiology , Malaria, Vivax/epidemiology , Microscopy/methods , Polymerase Chain Reaction , Prevalence , Plasmodium falciparum/genetics , Plasmodium falciparum/immunology , Plasmodium vivax/genetics , Plasmodium vivax/immunology , Sensitivity and Specificity , Venezuela/epidemiologyABSTRACT
Se estudio la respuesta inmunologica del compartimiento humoral en el suero sanguineo y humor acuoso en tres grupos de pacientes: Grupo I: pacientes con uveitis; Grupo II con enfermedad sistemica autoinmune sin uveitis, y Grupo III: control.Los resultados senalan alteraciones locales en este sentido encontrandose elevacion de la IgG e IgA en los pacientes del Grupo I asi como la presencia del factor B y C3, los cuales se reportan en forma original; los complejos inmunologicos fueron detectados por dos metodos, siendo significativos los resultados en el Grupo I