Biologic False-positive Research Articles

The treponema pallidum immobilization test in the cerebrospinal fluid: With a discussion of the phenomenon of chronic biologic false positivity in the cerebrospinal fluid

This study reports the experience with the TPI test in the cerebrospinal fluid of 43 patients in the diagnostic categories of early syphilis, latent syphilis neurosyphilis, and biologic false positive reactions, and correlates our results with those reported by other authors. The behavior of the TPI antibody in central nervous system syphilis appears to be similar to that of reagin. In latent syphilis there is disagreement between the two tests, in that there are patients with latent syphilis who have the TPI antibody in otherwise normal spinal fluids. It is probable that patients with latent syphilis who have demonstrable TPI antibody in the cerebrospinal fluid may be reclassified as a type of asymptomatic neurosyphilis. The precise significance of this phenomenon is as yet unknown, and the prognosis of such patients has not yet been established. Three patients are presented with chronic biologic false positive reactions in both blood serum and cerebrospinal fluid. It is suggested that alterations in the globulin fraction of the spinal fluid, probably secondary to tissue injury, are responsible for the false positive reactions, since these patients had brain tumor, probable collagen vascular disease, and probable sarcoidosis, respectively.