Serodiagnosis of human onchocerciasis: evaluation of sensitivity and specificity of a purified Litomosoides carinii adult worm antigen.
Sensitivity and specificity of a Litomosoides carinii macrofilariae aqueous crude extract and a purified antigen which was isolated by preparative flat bed electrofocusing, were evaluated for the immunodiagnosis of human onchocerciasis in 3 serological tests: Double diffusion test (DT), latex agglutination test (LAT) and ELISA. Testing sera from proven cases of onchocerciasis (n = 28), loiasis (n = 4) filariasis bancrofti (n = 4), and other non filarial helminth infections (n = 29) in all tests the purified antigen was clearly more sensitive and specific. Testing onchocerciasis sera highest sensitivity was found by ELISA (92.9%) followed by latex agglutination test (89.3%) and double diffusion test (82.1%). Specificity controls of the purified antigen with sera from patients with helminth infections others than filariases led to 0% (DT), 6.9% (LAT) and 10.3% (ELISA) false positive reactions. When the 3 tests were used in combination in a way that at least two positive reactions in different tests were regarded as necessary to declare a serum as positive, sensitivity increased to 100% and unspecific reactions were found only testing one serum (3.4%) originating from a case of cystic echinococcosis.
D000906:Antibodies / Q000032:analysis; D000941:Antigens / Q000276:immunology*; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes; D005370:Filarioidea / Q000276:immunology*; D006801:Humans; D005779:Immunodiffusion; D007841:Latex Fixation Tests; D009854:Onchocerca / Q000276:immunology; D009855:Onchocerciasis / Q000175:diagnosis*; D012698:Serologic Tests / Q000379:methods*
D000906:Antibodies; D000941:Antigens; D000939:Epitopes