Immunodiagnosis of Human Cysticercosis (Taenia solium): a Field Comparison of an Antibody-Enzyme-Linked Immunosorbent Assay (ELISA), an Antigen-ELISA, and an Enzyme-Linked Immunoelectrotransfer Blot (EITB) Assay in Peru
Universidad Peruana Cayetano Heredia, Department of International Health, Johns Hopkins University School of Hygiene and Public Health, Parasitic Diseases Branch, Division of Parasitic Diseases, Center for Infectious Diseases, Centers for Disease Control, Lima, Peru
We compared results of an enzyme-linked immunosorbent assay (ELISA) and an enzyme-linked immunoelectrotransfer blot (EITB) assay for the diagnosis of cysticercosis in sera and cerebrospinal fluid (CSF). Sera from 34 patients with confirmed cysticercosis were tested by both ELISA and EITB assays. Cerebrospinal fluid from some of these patients was also tested by ELISA for the presence of antibody (AB-ELISA) (n = 21) and antigen (AG-ELISA) (n = 15). Specificity in sera was examined by testing 51 serum samples from Bangladesh, where cysticercosis is not endemic. Cross-reactivity was evaluated in sera from patients with Echinococcus granulosus (hydatid) and Hymenolepis nana infections. Sensitivity in detecting cysticercosis in sera was 94% by EITB and 65% by AB-ELISA (P < 0.01). Sensitivities in the CSF tested by EITB, AB-ELISA, and AG-ELISA were 86%, 62%, and 67%, respectively. The specificity of the EITB was 100%, while that of AB-ELISA was 63% (P < 0.01). Cross-reactions occurred in the AB-ELISA with 11% and 20% of sera from hydatid and H. nana patients, respectively. Our results demonstrate that the EITB is the best assay available for the diagnosis of cysticercosis in both sera and CSF.
The other members of the Cysticercosis Working Group in Peru are R. Castillo, M. Alvarez, A. Guevara, C. Carcamo, G. Herrera (Universidad Peruana Cayetano Heredia); C. Evans (St. Thomas's University, UK); E. Gonzales, M. Castro (A.B. Prisma); A. Chavera, K. Campos, A. Delgado, A. Chavez, H. Bazalar (Universidad Nacional Mayor de San Marcos); M. Martinez, M. Porras, M. Alvarado, E. Orrillo, L. Palomino, S. Escalante, G. Alban, L. Trelles, N. Rios-Saavedra, M. Velarde, J. Cuba, M. Soto (Instituto Nacional de Ciencias Neurologicas); J. Cabrera, P. Campos (Hospital Cayetano Heredia); E. Herrera, E. Molina (Instituto Nacional de de Oftalmologia); F. Yalan (Instituto Nacional de Salud del Nino); J. Alfaro, D. Morote (Hospital Edgardo Rebagliati); U. Rocca (Hospital Guillermo Almenara); M. Castaneda, M. Ayala (Hospital Dos de Mayo); M. Lescano, L. E. Vasquez, N. Riva, L. Samaniego, J. Matsuoka (Instituto de Medicina Tropical de San Martin).