Comparative study of amplification systems in immunoenzyme assays for the diagnosis of American tegumentary leishmaniasis.
We compared the accuracy and reliability of three amplification systems for enzyme immunoassays in the detection of specific IgG antibodies for the diagnosis of cutaneous leishmaniasis caused by Leishmania (Viannia) braziliensis in patients from an endemic area in Rio de Janeiro, Brazil. Partially soluble antigens obtained from the promastigote forms of L. (V.) braziliensis were used. For development of the reaction, two chromogens, 1,2-orthophenylenediamine (OPD) and 3,3',5,5'-tetramethylbenzidine (TMB), and a fluorogen, 4-methylumbelliferylphosphate (MUP), were tested. The performance of each system was compared using the following parameters: accuracy, intraclass correlation coefficient (ICC), and area under the receiver operating characteristic (ROC) curve. Sensitivity was the same (97.4%) for all systems. The reliability was excellent (ICC = 98.6, 98.7, and 99.1%) and specificity was 93.7, 95.8, and 97.4% for OPD, MUP, and TMB, respectively, showing no statistical significance. Despite the absence of differences in the performance of the three systems, the use of TMB is suggested because of its operational advantages, such as low cost compared with fluorogens, easy manipulation, greater stability, and lower toxicity.
Nascimento
Lílian Dias
LD
Laboratório de Vigilância em Leishmanioses, Instituto de Pesquisa Clínica Evandro Chagas-IPEC/FIOCRUZ, Rio de Janeiro, RJ, Brazil. lilian.nascimento@ipec.fiocruz.br
Passos
Sonia Regina Lambert
SR
Mouta-Confort
Eliame
E
Santiago
Marta de Almeida
Mde A
Alves
Andreia Silva
AS
Madeira
Maria de Fátima
Mde F
Schubach
Armando de Oliveira
Ade O
Marzochi
Mauro Célio de Almeida
MC
D000818:Animals; D000953:Antigens, Protozoan / Q000276:immunology; D001560:Benzidines / Q000737:chemistry; D016001:Confidence Intervals; D006801:Humans; D006923:Hymecromone / Q000031:analogs & derivatives / Q000737:chemistry; D007124:Immunoenzyme Techniques / Q000379:methods*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D007892:Leishmania braziliensis / Q000276:immunology; D016773:Leishmaniasis, Cutaneous / Q000175:diagnosis*; D010655:Phenylenediamines / Q000737:chemistry; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000953:Antigens, Protozoan; D001560:Benzidines; D007074:Immunoglobulin G; D010655:Phenylenediamines; C005359:4-methylumbelliferyl phosphate; C021758:3,3',5,5'-tetramethylbenzidine; D006923:Hymecromone; C034193:1,2-diaminobenzene