ABSTRACT
Antigen suspensions of enzyme-treated, formalin-fixed promastigotes of three species of Leishmania (L. donovani, L. tropica, and L. braziliensis) were evaluated by using the direct agglutination test with serum samples from healthy individuals and patients with confirmed cases of visceral and cutaneous leishmaniasis. High cross-reactivity was obtained with the three antigens in tests with leishmania sera. Sera from patients with kala-azar were 61% to 96% positive when tested with all three antigens. In tests with sera from patients with American cutaneous leishmaniasis, 81% were positive with L. donovania and L. braziliensis antigen, whereas only 54% to 55% were positive with the other two antigens. Normal sera were reactive at low dilutions of 1:16 or less with L. braziliensis antigens. Normal sera tested with L. tropica antigen reacted to a titer of 128.
Subject(s)
Agglutination Tests , Leishmaniasis/diagnosis , Algeria , Antibodies/analysis , Chagas Disease/diagnosis , Chile , France , Humans , Immunologic Techniques , India , Leishmania/immunology , Leishmaniasis, Mucocutaneous/diagnosis , Leishmaniasis, Visceral/diagnosis , Panama Canal Zone , Trypanosoma cruzi/immunology , United StatesABSTRACT
A micro enzyme-linked immunosorbent assay (ELISA) for antibodies to Trypanosoma cruzi was evaluated and the results obtained by ELISA were compared with those obtained by the complement fixation test (CF) and indirect fluorescent antibody test (IFA). Fifty sera collected from residents of the southeastern United States all had reciprocal ELISA titers less than or equal to 320. Similarly, serum samples from 17 patients with T. cruzi infection proven by xenodiagnosis had reciprocal ELISA titers of greater than or equal to 1,280. Specimens from 302 El Salvador Army recruits were tested by ELISA, IFA, and CF. Excellent correlation was observed between results obtained by the three serologic tests; 62.9% of the samples were negative by each of the three tests and 24.5% were positive by all. Overall, 29.5% of the sera were positive for antibodies to T. cruzi by ELISA, 29.5% by IFA, and 31.5% by CF. The data suggest that the micro ELISA is a promising serologic test for measuring antibodies to T. cruzi in individuals and in populations.
Subject(s)
Chagas Disease/immunology , Enzyme-Linked Immunosorbent Assay , Immunoenzyme Techniques , Adolescent , Adult , Aged , Antibodies/analysis , Chagas Disease/diagnosis , Child , Child, Preschool , Complement Fixation Tests , Female , Fluorescent Antibody Technique , Humans , Infant , Male , Middle Aged , Trypanosoma cruzi/immunologyABSTRACT
Over a 2-year period two cases of dermal leishmaniasis of special interest were recognized in Texas. The first occurred in 1972 in a 74-year-old woman who had residences in Dilworth and Gahzales, Gonzales County, and the other was in a 56-year-old man from Kenedy, Karnes County, in 1974. Both cases were biopsy- and culture-positive, and the second patient exhibited anti-Leishmania antibodies by indirect immunofluorescent antibody and direct agglutination tests. Epidemiologic investigation revealed no association between the two cases and suggested that both patients had acquired their infections locally in southern Texas. Moreover, serologic evidence of Leishmania infection was uncovered in a neighbor of the second case and in 3 dogs living nearby. Potential sylvatic reservoirs and arthropod vectors of the disease are resident in the area. Epidemiologic data suggest that dermal leishmaniasis is endemic in south-central Texas.
Subject(s)
Leishmaniasis/epidemiology , Adolescent , Aged , Animals , Antibodies/analysis , Cricetinae , Dogs , Female , Humans , Leishmania/immunology , Leishmaniasis/diagnosis , Male , Mesocricetus , Middle Aged , TexasABSTRACT
The enzyme-linked immunosorbed assay test was positive in 37 of 41 patients (90%) suspected of having clinical Toxocara infections. The antigen used in this test is prepared from the Toxocara egg and is felt to be extremely specific in making the diagnosis. The prevalence of Toxocara infection is much greater than previously believed. It is hoped that this test will help the surgeon fell more secure in not enucleating eyes containing masses suggestive of Toxocara infection.