RESUMO
Fourty hydatidosis patients and 36 patients with various parasitic diseases taken from Ain Shams University Hospitals and 15 normal controls as well were subjected to clinical examination, stool and urine examination, serological examination using indirect hemagglutination (IHA), counterimmunoelectrophoresis (CIEP) and enzyme-linked immunosorbent assay (ELISA) tests with crude and partially antigens for hydatidosis. Partial purification of crude hydatid fluid antigen abolished reactions in IHA test, reduced in ELISA or had no effect on cross reactions in the CIEP test. The crude antigen was more sensitive than the purified antigen in all tests applied. Using crude antigen, IHA (83%) was the most sensitive test followed by ELISA (68%) and then CIEP (60%) tests. In case of partially purified hydatid fluid antigen, CIEP was the most sensitive (58%) test with the purified peak I antigen followed by IHA test with peak III (48%) then ELISA with purified peak I (45%). In all serological tests applied, hepatic hydatidosis cases gave the highest reactions followed by cases of combined hepatic and pulmonary infections and then pulmonary cases alone.
Assuntos
Antígenos de Helmintos , Equinococose/diagnóstico , Contraimunoeletroforese/métodos , Reações Cruzadas , Equinococose Hepática/diagnóstico , Equinococose Pulmonar/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Testes de Hemaglutinação/métodos , Humanos , Doenças Parasitárias/diagnóstico , Valores de Referência , Sensibilidade e Especificidade , Testes Sorológicos/métodosRESUMO
Three serological tests: Immunodiffusion (ID), Counterimmunoelectrophoresis (CIEP) and Enzyme-linked immunosorbent assay (ELISA) were used to study the role of crude adult worm antigen (CAWA) of Toxocara canis and each of its purified fractions in the serodiagnosis of human toxocariasis. Sensitivities of the three tests were lower in the ocular than in the visceral group, using different antigens. Purified fraction 1 showed more sensitive and specific reactions in the three tests, compared to CAWA or purified fraction 2 (P-F2) antigen. The other purified fractions (P-F3, P-F4 and P-F5) gave no positive reactions in any of the three tests. Using P-F1 antigen, ELISA was the most sensitive technique for diagnosis of both visceral and ocular toxocariasis followed by CIEP and then ID and the difference was statistically significant. However, CIEP was the most specific test followed by ELISA and lastly ID test. The ELISA test using Excretory-Secretory (E-S) larval antigen of Toxocara canis was less sensitive than the ELISA test using P-F1, although it was 100% specific. Thus, ELISA test using P-F1 is the test of choice for diagnosis of human toxocariasis, but when the specificity of a reaction is in doubt, CIEP test using the same antigen can be of value.