Diluted patient serum is added to wells coated with purified antigen. Specific antibody, if present, binds to the antigen. All unbound materials are washed away and the enzyme conjugate is added to bind to the antibody-antigen complex, if present. Excess enzyme conjugate is washed off and substrate is added. The plate is incubated to allow the hydrolysis of the substrate by the enzyme. The intensity of the color generated is proportional to the amount of IgG specific antibody in the sample.
ITreponema pallidumi is the causative agent of syphilis a contagious and infectious systemic disease characterized by periods of active florid manifestations and by years of symptomless latency. Syphilis is traditionally classified as acquired or congenital, each being further subided on the basis of the natural course of the disease. In acquired syphilis, infection is usually transmitted by sexual intercourse.The incubation period of syphilis can vary from 1 to 13 weeks, but usually from 3 - 4 weeks.Untreated patients with primary or secondary syphilis having active lesions are the most infectious, and the risks of contagion are greatest during the first 2 years of infection.Virtually every organ and tissue of the body is affected, including most body fluids.Over 80% of patients have mucocutaneous lesions, 50% have generalized enlargement of the lymph nodes, and about 10% have lesions of the eyes, bones and joints, meninges, liver, and spleen.Mild constitutional symptoms of malaise, headache, anorexia, nausea, aching pains in the bones, and fat IgAbility are often present. Congenital syphilis is the result of passage of iT. pallidumi across the placenta.Clinical manifestations may be present at birth but are more often seen at 3 weeks to 6 months of age.Two types of antibodies are produced by iT. pallidumi: nontreponemal antibodies (reagin) and treponemal antibodies.ELISA for detection of IgG and IgM antibodies is becoming the Gold standard for the diagnosis of syphilis.