Enzyme immunoassay for the diagnosis of cat-scratch disease defined by polymerase chain reaction

Whole-cell immunofluorescent antibody (IFA) tests for detection of anti-Bar tonella henselae immunoglobulin (Ig) G are commonly used to diagnose cat-sc ratch disease (CSD). The need to cultivate B. henselae in Vero cells for an tigen preparation and the absence of routinely applied IFA assays for IgM c onstitute the major disadvantages of this form of test. We describe the res ults of an enzyme immunoassay (EIA) for IgM and IgG that used N-lauroyl-sar cosine-insoluble outer membrane antigens from agar-grown B. henselae perfor med in 84 patients with definite CSD (regional lymphadenitis, cat contact, and greater than or equal to1 confirmatory test: polymerase chain reaction, skin test, or B. henselae culture). Although this method has been used as a diagnostic tool in several case reports, it has not previously been evalu ated in a large study of definitively proven CSD cases. Results of this stu dy indicate that the EIA described herein can play an important role in the serodiagnosis of CSD, although improvement of the sensitivity, particularl y that of the IgM, would be desirable.